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Emotions and cognitions associated with bingeing and weight control behavior in bulimia
Journal of Psychosomatic Research, Vol. 40, No. 3, pp. 317-328, 1996 Copyright © 1996 Elsevier Science Inc. All rights reserved. 0022-3999/96 $15.00 + .00
ELSEVIER
0022-3999(95)00641-9
EMOTIONS A N D COGNITIONS ASSOCIATED WITH BINGEING A N D WEIGHT CONTROL BEHAVIOR IN BULIMIA A N N E L. P O W E L L and MARK H. T H E L E N * (Received 30 August 1995; accepted 4 October 1995) Abstract- The examination of cognitionsand emotionsduring the bulimic cycleis critical in understanding
possible maintenance factors involvedin bulimia. In this study, 22 bulimics and 22 nonbulimics recorded their thoughts and feelingsevery2 wakinghours over a 6-dayperiod. Bulimicsadditionallyrecorded their moods and thoughts during their binges and compensatorybehaviors (e.g., purging, exercise). Higher levels of negative affect were reported at all stages of the cyclecompared to baseline, although negative affectdecreased after the compensatorybehavior stage. Subjectsalso reported strongerdistorted cognitions before and after the binge compared to baseline. One of the distorted cognitions (feeling fat) decreased in strength after subjects engagedin compensatorybehavior. Additionalanalysesrevealedthat most levels of negative affect and distorted cognitions were elevated prior to binges as compared to meals. Finally, negative affect and distorted cognitions were stronger after binges than after meals. Keywords:
Binge-Purgecycle; Bulimia; Distorted cognitions; Negative emotions. INTRODUCTION
Negative moods and distorted cognitions play a critical role in the initiation and maintenance of bulimia nervosa. Especially important is the way in which emotions and thoughts change across stage o f the bulimic cycle and perpetuate the cycle. Previous research has assessed emotions at various stages o f the cycle, but changes in cognitions have not been systematically examined. The examination of cognitions may provide additional insight into the maintenance of bulimia and may suggest avenues for more direct cognitive-behavioral interventions. Methodological problems in this area of research make assimilation o f the findings into a coherent picture difficult. In addition, the findings in many of the studies are contradictory. One exception exists, however, in that all of the studies that examined pre-binge moods supported the notion that negative mood precedes the binge [ 1-11 ]. Unfortunately, there is much less consistency regarding the remaining stages. Whereas Johnson and Larson [7] found a worsening o f mood during the binge and Elmore and de Castro [5] reported that depression increased over the course of the binge, other researchers reported an improvement in mood [1, 2]. Despite the fact that the methodology involved the use of a retrospective questionnaire, Hsu's [6] study may clarify the inconsistency in that he differentiated between the first and latter parts of *University of Missouri-Columbia Correspondenceshouldbe addressed to Anne Powell, Ph.D., AdamsCommunityMental Health Center, 4371 E. 72nd Avenue, CommerceCity, CO 80022. 317
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a binge a n d f o u n d that d y s p h o r i c m o o d decreased d u r i n g the first p a r t a n d increased d u r i n g the l a t t e r p a r t o f the binge when subjects were feeling full. A f t e r the binge, A b r a h a m a n d B e u m o n t f o u n d t h a t [1] there was a decrease in anxiety, b u t Rosen, Leitenberg, F o n d a c a r o , G r o s s , a n d W i l l m u t h [13] r e p o r t e d an increase in anxiety, a n d C o o p e r et al. [12] r e p o r t e d an increase in several different negative m o o d states. C o o p e r a n d Bowskill [2] also f o u n d t h a t anxiety a n d loneliness r e m a i n e d high after the binge. S c h l u n d t et al. [10] d e t e r m i n e d that negative m o o d was elevated p r i o r to vomiting. A b r a h a m a n d B e u m o n t [1] f o u n d that d u r i n g the purge there was a decrease in anxiety. Similarly, H s u [6] d e t e r m i n e d that subjects p r i m a r i l y felt relieved. A f t e r the purge, a decrease in a n x i e t y [8, I 1], a sense o f relief a n d a feeling o f security [12] a n d less a n g e r [7] were r e p o r t e d . O n the other h a n d , there was an elevated level o f d e p r e s s i o n [5, 6, 8] a n d sadness [7]. Hsu [6] f o u n d that guilt decreased, whereas J o h n s o n a n d L a r s o n [7] r e p o r t e d an increase in guilt. Davis et al. [4] d e t e r m i n e d t h a t m o o d after the purge was worse t h a n the m o o d b e f o r e the binge, a n d J o h n s o n a n d L a r s o n [7] f o u n d that there was an increase in feelings o f s h a m e a n d weakness. Finally, Steinberg et al. [11] r e p o r t e d that the purge decreased a n x i e t y for b o t h b o r d e r l i n e a n d n o n b o r d e r l i n e p e r s o n a l i t y - d i s o r d e r e d subjects, whereas the p u r g e decreased levels o f depression for the b o r d e r l i n e g r o u p only. Because the results o f the research to date are c o n t r a d i c t o r y , this s t u d y a t t e m p t e d to further e l u c i d a t e the p a t t e r n o f e m o t i o n s d u r i n g the bulimic cycle a n d to i m p r o v e u p o n the existing research in several ways. First, unlike the previous studies which a d d r e s s e d o n l y some o f the stages, the present s t u d y e x a m i n e d all o f the stages o f the bulimic cycle. S e c o n d , the m a j o r i t y o f research in this a r e a has relied on retrospective d a t a with some n o t a b l e exceptions [2-5, 7, 8, 13]. T h i r d , cognitions were e x a m i n e d because this has been a neglected a r e a o f research. In o n e o f the few studies o f its kind, Lingswiler et al. [9] r e p o r t e d that d i s t o r t e d c o g n i t i o n s were elevated p r i o r to the binge. H s u [6] f o u n d that c o g n i t i o n s that related to giving in to the binge were extremely c o m m o n d u r i n g the early p a r t o f the binge. H o w e v e r , the r a n g e o f cognitions a n d stages o f the b u l i m i c cycle e x a m i n e d in these studies were severely restricted. T h e r e f o r e , we u n d e r t o o k a p r o s p e c t i v e study in which e m o t i o n s a n d cognitions were e x a m i n e d at all o f the stages o f the b u l i m i c cycle to clarify the findings in this area.
METHOD Subjects Twenty-two bulimic and 22 nonbulimic females, recruited from introductory psychology classes at a midwestern university, served as subjects in this study. Inclusion criteria required that bulimic subjects score at least 94 on the Bulimia Test-Revised (BULIT-R; [14]). This cutoff score, 10 points below the suggested cutoff score for bulimia, was utilized to ensure that all possible bulimics would be identified. Subjects were also required to fulfill DSM-III-R [15] criteria for Bulimia Nervosa as determined by a semistructured clinical interview, including the criteria of an average of 2 binges per week for 3 months. Forty-eight subjects were identified as having a score of 94 or above on the BULIT-R. Of the 42 who were contacted and interviewed by the first author, 23 met inclusion criteria. However, one subject did not complete the study. The bulimic sample, according to their self-reports, consisted of 9 exercisers/restricters, 5 restricters, 2 vomiters/laxative users, 2 vomiter/exercisers, 1 laxative user/restricter, 1 vomiter/restricter, 1 exerciser, and 1 vomiter. Subjects reported an average binge history of 4.32 years. Seven subjects had been in treatment for bulimia previously, although none were in treatment during the study. Inclusion criteria for the nonbulimic subjects required that subjects score below 78 on the BULIT-R and endorse responses on the questionnaire indicating that they did not binge or purge. In addition, the
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presence of bulimia was further assessed by a clinical interview conducted by the first author. One subject was excluded from the study because she indicated that she previously had been bulimic. Another subject's data was excluded because she failed to complete the study. The bulimic and nonbulimic samples did not differ significantly in terms of age, t(23) = 0.86, NS (bulimic group M = 20.25 years, nonbulimic group M = 19.33), or weight, t(42)= 0.65, NS (weight/height ratio). None of the sample were 85070 or less than their ideal weight according to the Metropolitan Height and Weight Tables for Adults (1983). Seven bulimics and 7 nonbulimics were overweight according to the Metropolitan Tables.
Measures The Bulimia Test-Revised (BULIT-R; [14]). The BULIT-R is a 28-item, self-report instrument designed to assess DSM-III-R criteria for Bulimia Nervosa [14]. This instrument has demonstrated [14] good test-retest reliability (0.95), sensitivity (0.62), specificity (0.96), positive predictive value (0.82), and negative predictive value (0.89). TheSemi-StructuredInterviewforBulimia(SSIB;[I7]). The SSIB, a semistructured interview based on DSM-III-R criteria for bulimia, demonstrated good interrater reliabilities of 0.70 (kappa) in a previous study. Validity testing has not been conducted with this instrument, although it has face validity. The Bulimic Thoughts Questionnaire (BTQ; [18]). On this 20-item measure of bulimic thoughts [18], respondents rated the frequency with which they experienced particular thoughts in the past week on 5-point Likert scales. A 3-factor structure was determined by factor analysis: 1) self-schema for weight, 2) self-et~cacy expectations regarding dieting, and 3) salient beliefs. This instrument effectively discriminated individuals of the bulimia group from those of the control group, and it was sensitive to changes in cognitions after cognitive-behavioral treatment. The Multiple Affect Adjective Check List (MAACL; [19]). A 5-factor structure was derived by factor analyses on this instrument that assesses currently experienced emotions: 1) hostility, 2) depression, 3) anxiety, 4) positive affect, and 5) sensation seeking. Internal reliabilities were good for all of the scales. Because this instrument measured "states" rather than traits, test-retest reliabilities were not very high for the various factors, ranging from near zero to 0.34. Emotion and Cognition Scales (ECS). These scales (shown in the Appendix) contain 6 items that measure 3 mood variables (2 items each for hostility, depression, and anxiety) and 6 items that measure 3 cognitive variables (2 items each for distorted self-schema regarding body weight, poor self-efficacy regarding diets, and irrational salient beliefs concerning food and weight). Two variables from the MAACL, sensation seeking and positive affect, were not included on the ECS to keep the form as short as possible and because they were not of primary interest. The 2 mood items with the highest loadings on hostility, depression, and anxiety dimensions were taken from the MAACL [19]. However, there was one exception. Although "tormented" had the second highest loading on the depression factor, "sad" (third highest loading) was included because it was not clear whether all subjects would have a good understanding of the term "tormented." The cognitive items were taken from the BTQ [18] and were selected because they had the highest loadings on their respective factors. Although the items derived from the original scales were measured in terms of the frequency of thoughts (BTQ) or in terms of whether or not a subject was experiencing a particular emotion (MAACL), these items were changed to 5-point Likert scales ranging from being experienced "not at all" strongly to being experienced "very" strongly. The format was changed to provide interval data that was more amenable to data analyses than dichotomous data. The ECS forms were completed by the subject every 2 waking hours. The first form in each packet began at 2 A.M., and the last form ended at 12 A.M. On each form, there was a place to indicate the date the slip was completed, whether the subject completed the questionnaire at the requested time, and whether the subject had a snack, a meal, or a binge in the preceding 2 hours. In addition, subjects were asked to indicate one thought and one emotion that they were experiencing most strongly to help them get in touch with their feelings and thoughts before completing the scale of other thoughts and emotions. Ninety percent of the forms were reportedly completed at the correct time, whereas 9°7o were completed retrospectively. On 1070of the forms, there was no indication of the time of completion. Emotions and Cognitions during a Binge Scale (ECDBS). These scales were similar to the ECS described in the previous section. However, the subjects were asked to rate their cognitions and emotions at the beginning of each binge, during the middle of each binge (based on prior estimates of the length of their typical binges), immediately after each binge, and after each compensatory behavior. In addition, subjects specified the type of compensatory behavior technique used. Eighty-six percent of these forms were reportedly completed at the requested time; 14070 were not.
Procedure Subjects were informed that the study involved recording their thoughts and feelings every 2 waking hours for 6 days and, for those who were bulimic, throughout the bulimic cycle. They were given 6 sets
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of packets of the ECS to record their thoughts and feelings every 2 waking hours, even if they were bingeing or purging at the time. Bulimic subjects were also given 4 sets of the ECDBS on which they were to record their thoughts and feelings during the bulimic cycle. Subjects then completed the MAACL and the BTQ. Subjects were called every day of the experiment to help them remember to complete their forms. After completion of the experiment, subjects were weighed, debriefed, thanked, and given their experimental credit and/or monetary stipend. Bulimic subjects were then referred to one of the clinics on campus.
RESULTS
Reduction o f the dependent variables Utilizing data from control and bulimic subjects, correlational analyses were performed to determine the extent to which the two items used to measure each cognitive and mood factor on the ECS were correlated. The two items that measured each mood and cognitive variable were correlated at 0.83 or higher. Therefore, responses to the items measuring each mood and cognitive variable were summed and averaged. Each variable was then correlated with its respective factor on the BTQ and the MAACL. The anxiety variable was significantly correlated with its respective factor on the MAACL, r = 0.55,p<0.0001. The depression (r= 0.58, p<0.0001) and hostility (r= 0.52, p<0.0003) variables were also significantly correlated with their respective factors on the MAACL. Because the MAACL was a "state" measure, it was not expected that the correlations would be extremely high. On the other hand, because subjects were asked to estimate the frequency of their thoughts over a 7-day period on the BTQ, the correlations between the ECS cognitive variables and the BTQ were expected to be higher. In fact, self-schema for weight was highly correlated with its respective factor on the BTQ (r= 0.89, p<0.0001), as was the salient beliefs factor regarding food and weight with its respective factor (r = 0.87, p<0.0001 .) However, self-efficacy regarding dieting was not as highly correlated with its respective factor (r = 0.46, p<0.002). Because of the lower correlation (indicating that the ECS and BTQ factors were not measuring the same factor) and because it did not correlate very highly with the remaining factors, the self-efficacy factor was excluded from the main analyses.
Comparison o f the bulimic and nonbulimic groups on the BTQ, MAACL, and ECS variables A one-way (group) multivariate analysis of variance (MANOVA) revealed a significant effect for group on the 8 mood variables from the MAACL and the ECS, F(8, 35) = 7.50, p<0.0001 (Wilks' criterion). Similarly, a one-way (group) MANOVA performed on the 5 cognitive variables from the BTQ and the ECS was also significant, F(5, 38) = 45.91, p<0.0001. Table I reports the respective means, t values, and significance levels. To summarize, bulimics received higher scores on self-schema for weight and on salient beliefs regarding food and weight on the BTQ. In addition, bulimics endorsed higher levels of anxiety, depression, and hostility on the MAACL. However, nonbulimics scored higher on positive affect. The groups did not differ significantly on the sensationseeking variable. On the ECS (with data from the binge-weight control cycle removed), bulimics endorsed higher levels o f anxiety, depression, and hostility. Finally, bulimics' scores were higher on self-schema for weight and salient beliefs.
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Table I . - BTQ, MAACL, and ECS variable means Group means Variables BTQ Self-schema for weight Self-efficacy regarding dieting Salient beliefs regarding food and weight MAACL Anxiety Depression Hostility Positive effect Sensation seeking ECS Anxiety Depression Hostility Self-schema for weight Salient beliefs regarding food and weight
Bulimic
Nonbulimic
t
4.55 (0.44)
2.64 (0.73)
10.50"*
4.03 (0.35)
3.83 (0.27)
2.06*
3.81 (0.61)
1.58 (0.31)
15.21"*
0.42 0.36 0.18 0.16 0.38
(0.24) (0.28) (0.13) (0.14) (0.12)
0.10 (0.12) 0.08 (0.12) 0.04 (0.05) 0.37 (0.29) 0.44 (0.16)
5.78** 4.33** 4.73** 2.98** 1.43
2.56 2.46 2.27 4.02
(0.74) (0.92) (0.73) (0.86)
1.71 (0.42) 1.44 (0.37) 1.53 (0.35) 1.61 (0.61)
4.70** 4.81"* 4.28** 10.75"*
1.08 (0.21)
8.70**
3.39 (1.23)
Note. Higher numbers indicate a greater frequency or more extreme responses with the exception of less self-efficacy regarding dieting. Standard deviations are in parentheses. *p < 0.05; **p < 0.01. Comparisonofvariablesduringthebulimiccycleandatbaseline. The 22 bulimic subjects recorded 31 binges, with a modal number of 1 binge. Each subject binged at least once. For subjects who engaged in more than 1 binge, their data were averaged for subsequent analyses. It should be noted that, during the study, the bulimic subjects reported fewer binges than they had during the initial screening interview, most likely due to the inhibitory effects of self-monitoring. Twelve of the binges were followed by exercising, whereas 5 were followed by fasting or restriction of caloric intake. Episodes of vomiting followed 5 of the binge episodes, and the use of laxatives followed 3. Finally, the combination of exercising and restricting caloric intake followed 2 o f the binges. Because most of the subjects engaged in other compensatory behavior besides vomiting or using laxatives, the terms compensatory behavior or weightcontrol technique will be used rather than purging. The average length of the binges during the study was 37 minutes. Two subjects binged but did not engage in any compensatory behavior. In addition, two other subjects each recorded 2 binges but only one compensatory behavior. Therefore, means for "after the compensatory behavior" f r o m subjects who provided data were substituted for the missing data to allow analysis of the data. Because the m o o d and cognitive factors were conceptualized as different entities, two separate one-way (stage of the bulimic cycle) M A N O V A s with repeated measures on stage were performed for the cognitive and m o o d variables. The 6 stages of the bulimic cycle were as follows: baseline score, which was a separate mean for each subject of ECS data at all time points excluding measures completed during the bulimic cycle; before the binge; beginning o f the binge; middle of the binge; after the binge; and after the compensatory behavior. A one-way (stage) M A N O V A with repeated
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measures was performed on the data from the 3 mood variables, F(15, 7)=22.36, p<0.001 (Wilks' criterion). A one-way (stage) MANOVA with repeated measures on the 6 stages was also found to be significant for the 2 cognitive variables, F(10, 12) = 5.78, p<0.003. Eighteen follow-up one-way (stage) MANOVAs with repeated measures on 2 stages for the mood and cognitive variables were conducted as follows: the baseline data were compared with each of the 5 stages of the bulimic cycle to determine possible maintenance factors. In addition, each stage was compared with its subsequent stage to determine changes over the cycle. To simplify the presentation of the results, only significant findings will be mentioned in the following sections. For the mood variables, "baseline" was significantly different from all of the following stages: "before the binge," F(3, 19) = 3.70, p<0.03; "beginning of the binge," F(3, 19) = 4.20, p <0.02; "middle of the binge," F(3, 19) = 7.58, p<0.002; "after the binge," F(3, 19)= 14.94, p<0.001; and "after the compensatory behavior," F(3, 19)= 6.46, p<0.003. Comparing the mood variables across stage, only "after the binge" versus "after the compensatory behavior" was significant, F(3, 19)= 6.66,/~0.003. To probe the significant MANOVAs, separate one-way (stage) analyses of variance (ANOVA) with repeated measures on 2 stages were conducted. Table II contains the means and comparisons of the emotions and cognitions at the different stages of the bulimic cycle. In terms of anxiety, most of the subsequent stages were higher than "baseline:" "before the binge," F(1,21) = 4.91, p<0.04; "beginning of the binge," F(1, 21)= 8.21,/~0.01; "middle of the binge," F(1, 21)= 8.23, p<0.01; and "after the binge," F(1, 21) = 13.25, p<0.002. Finally, anxiety "after the binge" was significantly higher than "after the compensatory behavior," F(1, 21)-- 12.41, p<0.002. In sum, these analyses indicated that subjects experienced more anxiety before, during, and after the binge than at baseline. However, anxiety decreased to baseline levels after subjects engaged in a weight-control technique. When we examined depression, a number of mean scores were significantly higher than "baseline": "before the binge," F(1, 21)= 11.05, p<0.004; "beginning of the binge," F(1, 21)=7.13, p<0.02; "middle of the binge," F(1, 21)=20.49, p<0.0002; "after the binge," F(1,2 l) = 42.77,/~0.0001; and "after the compensatory behavior," F(1, 21)= 8.79,/~0.008. Finally, the mean for depression "after the binge" was significantly higher than the "after the compensatory behavior" mean, F(1, 21) = 10.75, p<0.004. That is, subjects experienced more depression throughout all stages of the cycle compared to baseline, with a significant decrease after the compensatory behavior. However, depression was not reduced to baseline levels. All of the subsequent means for hostility were higher than "baseline": "before the binge," F(I, 21) = 8.21, p(0.01; "beginning of the binge," F (1, 21) = 7.98,/~0.02; "middle of the binge," F(1,2 l) = 20.28, p<0.0002; "after the binge," F(1,21) -- 33.11, /~0.0001; and "after the compensatory behavior," F(1, 21)--7.62, p<0.02. Finally, hostility scores "after the binge" were significantly greater than scores "after the compensatory behavior," F(1, 21)= 6.23,/~0.03. Like the scores for depression, levels of hostility were elevated throughout all of the stages of the cycle and decreased after the compensatory behavior, but not to baseline levels. In terms of the cognitive variables, a one-way (stage) MANOVA with repeated measures on "baseline" versus "before the binge" was significant, F(2, 20)= 4.01, p<0.03. "Baseline" versus "after the binge" was significant, F(2, 20) = 17.62, p<0.001,
Emotions and cognitions
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Table III.-Variable means before meals and before binges Meal/Binge status Variables Anxiety Depression Hostility SSW SBFW
Pre-meal
Pre-binge
2.60 (0.75) 2.34 (1.00) 2.24 (0.87) 3.79 (1.02) 3.26 (1.31)
2.94 (1.19) 3.10 (1.08) 2.84 (1.22) 4.25 (0.88) 3.89 (1.27)
F 2.64 16.01"* 5.78* 9.45** 9.86**
Note. Standard deviations are in parentheses. SSW = self-schema for weight. SBFW = salient beliefs regarding food and weight. *p < 0.05; **p < 0.01. as was "baseline" versus "after the compensatory behavior," F(2, 20) = 3.56, p<0.05. Comparing the cognitive variables across stage, only "after the binge" versus "after the compensatory behavior" was significant, F(2, 20) = 5.04, p<0.02. Where the M A N O V A s were significant for the cognitive variables, one-way ANOVAs with repeated measures on 2 stages were performed. For self-schema for weight, there was a trend for subjects to more strongly believe they were fat "before the binge" than at "baseline,"F(1,21) = 3.38,p<0.09. Subjects were also feeling fat more strongly "after the binge" than at "baseline,"F(1,21) = 35.64, p<0.0001, and "after the compensatory behavior," F(1, 21)= 7.74, p<0.02. In terms of salient beliefs regarding food and weight, the subjects' "before the binge" mean was significantly higher than "baseline," F(1,21) = 8.40, p<0.009. "After the binge" salient beliefs were also significantly stronger than at "baseline," F(1, 21)= 15.78, p<0.0007, as were "after the compensatory behavior" salient beliefs, F(1, 21)=6.44, p<0.02.
Additional analyses Analyses were also conducted to determine differences in the bulimics' moods and cognitions before meals and before binges. A one-way (pre-binge vs. pre-meal) M A N O V A with repeated measures was performed to compare the emotions before the binges with those before the meals, F(3, 18) = 5.06,p<0.01. To probe the significant M A N O V A , a one-way (pre-binge vs. pre-meal) A N O V A with repeated measures was performed on the anxiety variable, but was not found to be significant. However, subjects felt more depressed and hostile before a binge than before a meal. (See Table III for means and F values.) In terms of the cognitive variables, the one-way (pre-binge vs. pre-meal) M A N O V A was significant, F(2, 19) = 5.48, p <0.02. One-way ANOVAs indicated that subjects felt heavier and endorsed more salient beliefs regarding food and weight before a binge than before a meal. (See Table III for means and F values.) A one-way (post-binge vs. post-meal) M A N O V A with repeated measures was also performed to compare the emotions experienced after the meals to those experienced after the compensatory behaviors, F(3, 19)= 13.36,/9<0.001. Two post hoc one-way ANOVAs with repeated measures indicated that subjects reported more anxiety, more depression, and more hostility after a binge than after a meal. (See Table IV for means and F values.)
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Table IV. - Variable means after meals and after binges Meal/Binge status Variables
Post-meal
Post-binge
F
Anxiety Depression Hostility SSW SBFW
2.55 (0.89) 2.47 (1.02) 2.28 (0.82) 4.00 (0.87) 3.35 (1.22)
3.51 (1.32) 3.83 (1.24) 3.65 (1.19) 4.76 (0.53) 4.02 (1.43)
12.67"* 38.13'* 30.51"* 32.23** 16.23"*
Note. Standard deviations are in parentheses. SSW = self-schema for weight. SBFW = salient beliefs regarding food and weight. **p < 0.01.
A one-way (post-binge vs. post-meal) MANOVA with repeated measures was also found to be significant for the cognitive variables, F(2, 20)= 16.19, p<0.001. Two one-way ANOVAs with repeated measures revealed that subjects reported stronger cognitions regarding feeling fatter and stronger salient beliefs regarding food and weight after binges than after meals. (See Table IV for means and F values.) DISCUSSION When compared to baseline, the levels of all negative affect reported by the bulimic subjects were elevated in the 2 hours preceding the binge, at the beginning of the binge, in the middle of the binge, and after the binge. After engaging in weight-control behavior, subjects' hostility and depression remained elevated, although anxiety decreased to baseline levels. For all 3 mood variables, however, scores were significantly higher after the binge than after the compensatory behavior. The finding that negative mood was elevated prior to the binge has been well substantiated in the literature [1, 3, 5, 7, 9]. However, the fact that negative mood was elevated throughout the bulimic cycle was somewhat surprising, as it is generally believed that bingeing decreases negative affect. The research in this area, however, is divided, with 2 studies finding a reduction in negative mood [1, 12] and 1 study finding an increase in negative affect [7]. The hypothesized negative affect reducing effects might have occurred only at the very beginning of the binge and may not have been measured by asking subjects to report their feelings 5 minutes into the binge and at the middle of the binge. Hsu [6] found that dysphoric mood increased over the course o f the binge which supports this hypothesis. Self-monitoring may also have sensitized subjects to the negative aspects of their behavior. Although hostility and depression decreased after the compensatory behavior, they did not return to baseline levels. Some researchers have found that negative affect, particularly depression and guilt, remained high after the purge behavior as well [4, 5, 7). Other studies, however, have not supported this finding [7, 11, 12]. Differences in sample composition (e.g., severity o f bulimia, presence of personality disorders) and methodologies (e.g., types of measures used) may account for these inconsistencies. Although hostility and depression remained high after subjects engaged in compensatory behavior, anxiety levels decreased to baseline levels. Similar results were found in other studies as well [1, 8, 11]. In terms of cognitions, subjects had elevated levels of salient beliefs regarding food and weight, and there was a trend for bulimics to
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more strongly endorse cognitions regarding feeling heavy before a binge than at baseline. Distorted cognitions before a binge were reported in other studies as well [6, 9]. Because subjects reported stronger cognitions regarding feeling heavy and believed that they could not maintain a diet, these thoughts, along with elevated levels of negative affect, may have served to break their dietary restraint. Not surprisingly, subjects more strongly endorsed statements concerning feeling heavy and salient beliefs regarding food and weight after the binge than at baseline. However, the compensatory behavior did not significantly decrease the endorsement of salient beliefs regarding food and weight, whereas it decreased thoughts o f being overweight. Although it is impossible to determine causation, there were a few important similarities among the patterns of results for the emotions and cognitions data. Reductions found in the strength of subjects' feelings of anxiety might have been related to the reductions in the strength of thoughts regarding feeling fat after the compensatory behavior. In addition, the elevated levels of salient beliefs regarding food and weight might have been related to the elevated levels of depression and hostility following the compensatory behavior compared to baseline. Other analyses examined the differences in mood and cognitions before meals and before binges. Levels of anxiety were not significantly different between the two conditions, which is inconsistent with findings from the Elmore and de Castro [5] study. Levels of depression and hostility, however, were more elevated prior to a binge than to a meal. In addition, subjects felt heavier and endorsed more salient beliefs regarding food and weight prior to a binge than they did to a meal. Lingswiler et al. [9] also found that subjects endorsed more dichotomous cognitions regarding food before a binge than before other eating situations. A final set of analyses examined bulimics' responses following meals and binges. Not surprisingly, subjects reported feeling more anxiety, depression, and hostility after a binge than after a meal. Elmore and de Castro [5] found that bulimics were more depressed and anxious after a binge than after a meal as well. Subjects in this study also endorsed more salient beliefs regarding food and weight and statements regarding feeling fat after a binge than after a meal. Thus, increased levels of negative affect and dysfunctional cognitions after a binge may have resulted in the use of a weight-control technique to prevent weight gain and relieve negative affect. Several methodological concerns should be noted. First, subjects were asked to self-monitor their thoughts and feelings during the bulimic cycle, which may have produced some "reactivity." In fact, most subjects indicated that self-monitoring resulted in fewer binges. Second, giving the subjects only a few options by which to report their emotions and cognitions provided limited information and was not completely adequate in assessing subjects' thoughts and feelings during the bulimic cycle. Another limitation of this study was the heterogeneity of the bulimic sample in terms of the compensatory behavior methods used and previous treatment experience. Because the sample size was small, analyses on the different subgroups could not be done. Future studies should differentiate the bulimic population in terms of previous treatment experience, type of compensatory behavior technique used, and presence of Axis I and Axis II disorders. Because our sample was not in treatment and was mainly engaged in weight-control techniques other than purging, the subjects most likely represented a less severe variant of bulimia and, as a result, were different from most of the samples in other studies. However, a recent study [20] did not indicate
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any significant differences on a number of personality and Axis I disorders between purgers and nonpurgers. M o s t i m p o r t a n t l y , this s t u d y i l l u s t r a t e s the i m p o r t a n c e o f e x a m i n i n g c o g n i t i o n s a c r o s s s t a g e o f t h e b u l i m i c cycle. T h e p a t t e r n o f c h a n g e s o v e r t h e b u l i m i c cycle i n d i c a t e s a n i m p o r t a n t r o l e f o r c o g n i t i o n s in t h e p e r p e t u a t i o n o f t h e cycle a n d c a n p o s s i b l y e l u c i d a t e p o i n t s o f i n t e r v e n t i o n in t h e c o g n i t i v e - b e h a v i o r a l t r e a t m e n t o f bulimia. However, more research should be conducted with a broader scope of cognit i o n s t o m o r e c o m p l e t e l y u n d e r s t a n d b u l i m i c t h o u g h t s d u r i n g t h e b u l i m i c cycle.
REFERENCES 1. ABRAHAM SF, BEUMONT PJV. How patients describe bulimia or binge eating. PsycholMed 1982; 12: 625-635. 2. COOPER P J, BOWSKILL R. Dysphoric mood and overeating. Br JClin Psycho11986; 25: 155-156. 3. DAVIS R, FREEMAN F J, GARNER DM. A naturalistic investigation of eating behavior in bulimia nervosa. J Consult Clin Psychol 1988; 56: 273-279. 4. DAVIS R, FREEMAN R, SOLYOM L. Mood and food: an analysis of bulimic episodes. JPsychiatr Res 1985; 19: 331-335. 5. ELMORE DK, DE CASTRO JM. Self-rated moods and hunger in relation to spontaneous eating behavior in bulimics, recovered bulimics, and normals. Int JEating Disord 1990; 9: 179-190. 6. HSU LKG. Experiential aspects of Bulimia Nervosa: implications for cognitive behavioral therapy. Behav Mod 1990; 14: 50-65. 7. JOHNSON C, LARSON R. Bulimia: an analysis of moods and behavior. Psychosom Med 1982; 44: 341-351. 8. KAYE WH, GWIRTSMAN HE, GEORGE DT, WEISS SR, JIMERSON DC. Relationship of mood alterations to bingeing behaviour in bulimia. Br J Psychiatry 1986; 149: 479-485. 9. LINGSWlLER VM, CROWTHER JH, STEPHENS MAP. Affective and cognitive antecedents to eating episodes in bulimia and binge eating. Int JEating Disord 1989; 8: 533-539. 10. SCHLUNDT DG, JOHNSON WG, JARRELL MP. A naturalistic functional analysis of eating behavior in bulimia and obesity. Adv Behav Res Ther 1985; 7: 149-162. 11. STEINBERG S, TOBIN D, JOHNSON C. The role of bulimic behaviors in affect regulation: different functions for different patient subgroups? Int J Eating Disord 1990; 9:51-55. 12. COOPER JL, MORRISON TL, BIGMAN OL, ABRAMOWlTZ SI, LEVIN S, KRENER P. Mood changes and affective disorder in the bulimic binge-purge cycle. Int JEating Disord 1988; 7: 469-474. 13. ROSEN JC, LEITENBERG H, FONDACARO KM, GROSS J, WILLMUTH M. Standardized test meals in the assessment of eating behaviors in bulimia nervosa: consumption of feared foods when vomiting is prevented. Int J Eating Disord 1985; 4: 59-70. 14. THELEN MH, FARMER J, WONDERLICH S, SMITH M. A revision of the Bulimia Test: The BULIT-R. Psychol Assess: J Consult Clin Psychol 1991; 3:119-124. 15. Diagn•stic and Statistica• Manua•• Third E dn-Revised. W ashingt •n• DC : American Psychiatric Ass•ciation, 1986. 16. Metropolitan height and weight tables for adults. New York: Metropolitan Life Insurance Company, Health and Safety Division, 1983. 17. MORENO AB, THELEN MH. Parental factors related to Bulimia Nervosa. Addict Behav 1993; 18: 681-689. 18. PHELEN PW. Cognitive correlates of bulimia: the Bulimic Thoughts Questionnaire. Int J Eating Disord 1987; 6: 593-607. 19. ZUCKERMAN M' L UBIN B' RINCK CM" C°nstructi°n ° f new scales f °r the Multiple Affect Adjective Check List. JBehav Assess 1983; 5: 119-129. 20. WALTERS EE, NEALE MC, EAVES L J, HEATH AC, KESSLER RC, KENDLER KS. Bulimia nervosa: a population-based study of purgers versus nonpurgers. IntJEatingDisord 1993; 13: 265-272.
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APPENDIX ECS Date: _
_
Time:
AM/PM
Did you have a snack, a meal, or a binge in the past two h o u r s ? If so, indicate which one(s) 1. Indicate the emotion or m o o d that you are feeling most strongly right now: 2. Indicate the strongest t h o u g h t that you are having right now: For each statement below, please fill in one o f the following n u m b e r s concerning how strongly you are experiencing the following feelings or thoughts right now. 1
2
3
4
5
not at all
slightly
somewhat
quite a bit
very m u c h
1. I feel nervous _ _ 2. I'm so fat _ _ 3. I feel sad _ _ 4. I am a t t r a c t i v e _ 5. I feel disgusted 6. I always fail on diets; why even try _ _ 7. I feel tense _ _ 8. I wish I were thinner _ _ 9. I feel lost _ _ 10. I like the way I look 11. I feel disagreeable 12. I'm not worth anything if I am fat Was this questionnaire completed at the indicated time (or within 5 minutes on either side)? (circle one).
YES N O
I f no, please try to remember to complete the next ones at the indicated times because the
information is m u c h more accurate that way.
ELSEVIER
0022-3999(95)00641-9
EMOTIONS A N D COGNITIONS ASSOCIATED WITH BINGEING A N D WEIGHT CONTROL BEHAVIOR IN BULIMIA A N N E L. P O W E L L and MARK H. T H E L E N * (Received 30 August 1995; accepted 4 October 1995) Abstract- The examination of cognitionsand emotionsduring the bulimic cycleis critical in understanding
possible maintenance factors involvedin bulimia. In this study, 22 bulimics and 22 nonbulimics recorded their thoughts and feelingsevery2 wakinghours over a 6-dayperiod. Bulimicsadditionallyrecorded their moods and thoughts during their binges and compensatorybehaviors (e.g., purging, exercise). Higher levels of negative affect were reported at all stages of the cyclecompared to baseline, although negative affectdecreased after the compensatorybehavior stage. Subjectsalso reported strongerdistorted cognitions before and after the binge compared to baseline. One of the distorted cognitions (feeling fat) decreased in strength after subjects engagedin compensatorybehavior. Additionalanalysesrevealedthat most levels of negative affect and distorted cognitions were elevated prior to binges as compared to meals. Finally, negative affect and distorted cognitions were stronger after binges than after meals. Keywords:
Binge-Purgecycle; Bulimia; Distorted cognitions; Negative emotions. INTRODUCTION
Negative moods and distorted cognitions play a critical role in the initiation and maintenance of bulimia nervosa. Especially important is the way in which emotions and thoughts change across stage o f the bulimic cycle and perpetuate the cycle. Previous research has assessed emotions at various stages o f the cycle, but changes in cognitions have not been systematically examined. The examination of cognitions may provide additional insight into the maintenance of bulimia and may suggest avenues for more direct cognitive-behavioral interventions. Methodological problems in this area of research make assimilation o f the findings into a coherent picture difficult. In addition, the findings in many of the studies are contradictory. One exception exists, however, in that all of the studies that examined pre-binge moods supported the notion that negative mood precedes the binge [ 1-11 ]. Unfortunately, there is much less consistency regarding the remaining stages. Whereas Johnson and Larson [7] found a worsening o f mood during the binge and Elmore and de Castro [5] reported that depression increased over the course of the binge, other researchers reported an improvement in mood [1, 2]. Despite the fact that the methodology involved the use of a retrospective questionnaire, Hsu's [6] study may clarify the inconsistency in that he differentiated between the first and latter parts of *University of Missouri-Columbia Correspondenceshouldbe addressed to Anne Powell, Ph.D., AdamsCommunityMental Health Center, 4371 E. 72nd Avenue, CommerceCity, CO 80022. 317
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a binge a n d f o u n d that d y s p h o r i c m o o d decreased d u r i n g the first p a r t a n d increased d u r i n g the l a t t e r p a r t o f the binge when subjects were feeling full. A f t e r the binge, A b r a h a m a n d B e u m o n t f o u n d t h a t [1] there was a decrease in anxiety, b u t Rosen, Leitenberg, F o n d a c a r o , G r o s s , a n d W i l l m u t h [13] r e p o r t e d an increase in anxiety, a n d C o o p e r et al. [12] r e p o r t e d an increase in several different negative m o o d states. C o o p e r a n d Bowskill [2] also f o u n d t h a t anxiety a n d loneliness r e m a i n e d high after the binge. S c h l u n d t et al. [10] d e t e r m i n e d that negative m o o d was elevated p r i o r to vomiting. A b r a h a m a n d B e u m o n t [1] f o u n d that d u r i n g the purge there was a decrease in anxiety. Similarly, H s u [6] d e t e r m i n e d that subjects p r i m a r i l y felt relieved. A f t e r the purge, a decrease in a n x i e t y [8, I 1], a sense o f relief a n d a feeling o f security [12] a n d less a n g e r [7] were r e p o r t e d . O n the other h a n d , there was an elevated level o f d e p r e s s i o n [5, 6, 8] a n d sadness [7]. Hsu [6] f o u n d that guilt decreased, whereas J o h n s o n a n d L a r s o n [7] r e p o r t e d an increase in guilt. Davis et al. [4] d e t e r m i n e d t h a t m o o d after the purge was worse t h a n the m o o d b e f o r e the binge, a n d J o h n s o n a n d L a r s o n [7] f o u n d that there was an increase in feelings o f s h a m e a n d weakness. Finally, Steinberg et al. [11] r e p o r t e d that the purge decreased a n x i e t y for b o t h b o r d e r l i n e a n d n o n b o r d e r l i n e p e r s o n a l i t y - d i s o r d e r e d subjects, whereas the p u r g e decreased levels o f depression for the b o r d e r l i n e g r o u p only. Because the results o f the research to date are c o n t r a d i c t o r y , this s t u d y a t t e m p t e d to further e l u c i d a t e the p a t t e r n o f e m o t i o n s d u r i n g the bulimic cycle a n d to i m p r o v e u p o n the existing research in several ways. First, unlike the previous studies which a d d r e s s e d o n l y some o f the stages, the present s t u d y e x a m i n e d all o f the stages o f the bulimic cycle. S e c o n d , the m a j o r i t y o f research in this a r e a has relied on retrospective d a t a with some n o t a b l e exceptions [2-5, 7, 8, 13]. T h i r d , cognitions were e x a m i n e d because this has been a neglected a r e a o f research. In o n e o f the few studies o f its kind, Lingswiler et al. [9] r e p o r t e d that d i s t o r t e d c o g n i t i o n s were elevated p r i o r to the binge. H s u [6] f o u n d that c o g n i t i o n s that related to giving in to the binge were extremely c o m m o n d u r i n g the early p a r t o f the binge. H o w e v e r , the r a n g e o f cognitions a n d stages o f the b u l i m i c cycle e x a m i n e d in these studies were severely restricted. T h e r e f o r e , we u n d e r t o o k a p r o s p e c t i v e study in which e m o t i o n s a n d cognitions were e x a m i n e d at all o f the stages o f the b u l i m i c cycle to clarify the findings in this area.
METHOD Subjects Twenty-two bulimic and 22 nonbulimic females, recruited from introductory psychology classes at a midwestern university, served as subjects in this study. Inclusion criteria required that bulimic subjects score at least 94 on the Bulimia Test-Revised (BULIT-R; [14]). This cutoff score, 10 points below the suggested cutoff score for bulimia, was utilized to ensure that all possible bulimics would be identified. Subjects were also required to fulfill DSM-III-R [15] criteria for Bulimia Nervosa as determined by a semistructured clinical interview, including the criteria of an average of 2 binges per week for 3 months. Forty-eight subjects were identified as having a score of 94 or above on the BULIT-R. Of the 42 who were contacted and interviewed by the first author, 23 met inclusion criteria. However, one subject did not complete the study. The bulimic sample, according to their self-reports, consisted of 9 exercisers/restricters, 5 restricters, 2 vomiters/laxative users, 2 vomiter/exercisers, 1 laxative user/restricter, 1 vomiter/restricter, 1 exerciser, and 1 vomiter. Subjects reported an average binge history of 4.32 years. Seven subjects had been in treatment for bulimia previously, although none were in treatment during the study. Inclusion criteria for the nonbulimic subjects required that subjects score below 78 on the BULIT-R and endorse responses on the questionnaire indicating that they did not binge or purge. In addition, the
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presence of bulimia was further assessed by a clinical interview conducted by the first author. One subject was excluded from the study because she indicated that she previously had been bulimic. Another subject's data was excluded because she failed to complete the study. The bulimic and nonbulimic samples did not differ significantly in terms of age, t(23) = 0.86, NS (bulimic group M = 20.25 years, nonbulimic group M = 19.33), or weight, t(42)= 0.65, NS (weight/height ratio). None of the sample were 85070 or less than their ideal weight according to the Metropolitan Height and Weight Tables for Adults (1983). Seven bulimics and 7 nonbulimics were overweight according to the Metropolitan Tables.
Measures The Bulimia Test-Revised (BULIT-R; [14]). The BULIT-R is a 28-item, self-report instrument designed to assess DSM-III-R criteria for Bulimia Nervosa [14]. This instrument has demonstrated [14] good test-retest reliability (0.95), sensitivity (0.62), specificity (0.96), positive predictive value (0.82), and negative predictive value (0.89). TheSemi-StructuredInterviewforBulimia(SSIB;[I7]). The SSIB, a semistructured interview based on DSM-III-R criteria for bulimia, demonstrated good interrater reliabilities of 0.70 (kappa) in a previous study. Validity testing has not been conducted with this instrument, although it has face validity. The Bulimic Thoughts Questionnaire (BTQ; [18]). On this 20-item measure of bulimic thoughts [18], respondents rated the frequency with which they experienced particular thoughts in the past week on 5-point Likert scales. A 3-factor structure was determined by factor analysis: 1) self-schema for weight, 2) self-et~cacy expectations regarding dieting, and 3) salient beliefs. This instrument effectively discriminated individuals of the bulimia group from those of the control group, and it was sensitive to changes in cognitions after cognitive-behavioral treatment. The Multiple Affect Adjective Check List (MAACL; [19]). A 5-factor structure was derived by factor analyses on this instrument that assesses currently experienced emotions: 1) hostility, 2) depression, 3) anxiety, 4) positive affect, and 5) sensation seeking. Internal reliabilities were good for all of the scales. Because this instrument measured "states" rather than traits, test-retest reliabilities were not very high for the various factors, ranging from near zero to 0.34. Emotion and Cognition Scales (ECS). These scales (shown in the Appendix) contain 6 items that measure 3 mood variables (2 items each for hostility, depression, and anxiety) and 6 items that measure 3 cognitive variables (2 items each for distorted self-schema regarding body weight, poor self-efficacy regarding diets, and irrational salient beliefs concerning food and weight). Two variables from the MAACL, sensation seeking and positive affect, were not included on the ECS to keep the form as short as possible and because they were not of primary interest. The 2 mood items with the highest loadings on hostility, depression, and anxiety dimensions were taken from the MAACL [19]. However, there was one exception. Although "tormented" had the second highest loading on the depression factor, "sad" (third highest loading) was included because it was not clear whether all subjects would have a good understanding of the term "tormented." The cognitive items were taken from the BTQ [18] and were selected because they had the highest loadings on their respective factors. Although the items derived from the original scales were measured in terms of the frequency of thoughts (BTQ) or in terms of whether or not a subject was experiencing a particular emotion (MAACL), these items were changed to 5-point Likert scales ranging from being experienced "not at all" strongly to being experienced "very" strongly. The format was changed to provide interval data that was more amenable to data analyses than dichotomous data. The ECS forms were completed by the subject every 2 waking hours. The first form in each packet began at 2 A.M., and the last form ended at 12 A.M. On each form, there was a place to indicate the date the slip was completed, whether the subject completed the questionnaire at the requested time, and whether the subject had a snack, a meal, or a binge in the preceding 2 hours. In addition, subjects were asked to indicate one thought and one emotion that they were experiencing most strongly to help them get in touch with their feelings and thoughts before completing the scale of other thoughts and emotions. Ninety percent of the forms were reportedly completed at the correct time, whereas 9°7o were completed retrospectively. On 1070of the forms, there was no indication of the time of completion. Emotions and Cognitions during a Binge Scale (ECDBS). These scales were similar to the ECS described in the previous section. However, the subjects were asked to rate their cognitions and emotions at the beginning of each binge, during the middle of each binge (based on prior estimates of the length of their typical binges), immediately after each binge, and after each compensatory behavior. In addition, subjects specified the type of compensatory behavior technique used. Eighty-six percent of these forms were reportedly completed at the requested time; 14070 were not.
Procedure Subjects were informed that the study involved recording their thoughts and feelings every 2 waking hours for 6 days and, for those who were bulimic, throughout the bulimic cycle. They were given 6 sets
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of packets of the ECS to record their thoughts and feelings every 2 waking hours, even if they were bingeing or purging at the time. Bulimic subjects were also given 4 sets of the ECDBS on which they were to record their thoughts and feelings during the bulimic cycle. Subjects then completed the MAACL and the BTQ. Subjects were called every day of the experiment to help them remember to complete their forms. After completion of the experiment, subjects were weighed, debriefed, thanked, and given their experimental credit and/or monetary stipend. Bulimic subjects were then referred to one of the clinics on campus.
RESULTS
Reduction o f the dependent variables Utilizing data from control and bulimic subjects, correlational analyses were performed to determine the extent to which the two items used to measure each cognitive and mood factor on the ECS were correlated. The two items that measured each mood and cognitive variable were correlated at 0.83 or higher. Therefore, responses to the items measuring each mood and cognitive variable were summed and averaged. Each variable was then correlated with its respective factor on the BTQ and the MAACL. The anxiety variable was significantly correlated with its respective factor on the MAACL, r = 0.55,p<0.0001. The depression (r= 0.58, p<0.0001) and hostility (r= 0.52, p<0.0003) variables were also significantly correlated with their respective factors on the MAACL. Because the MAACL was a "state" measure, it was not expected that the correlations would be extremely high. On the other hand, because subjects were asked to estimate the frequency of their thoughts over a 7-day period on the BTQ, the correlations between the ECS cognitive variables and the BTQ were expected to be higher. In fact, self-schema for weight was highly correlated with its respective factor on the BTQ (r= 0.89, p<0.0001), as was the salient beliefs factor regarding food and weight with its respective factor (r = 0.87, p<0.0001 .) However, self-efficacy regarding dieting was not as highly correlated with its respective factor (r = 0.46, p<0.002). Because of the lower correlation (indicating that the ECS and BTQ factors were not measuring the same factor) and because it did not correlate very highly with the remaining factors, the self-efficacy factor was excluded from the main analyses.
Comparison o f the bulimic and nonbulimic groups on the BTQ, MAACL, and ECS variables A one-way (group) multivariate analysis of variance (MANOVA) revealed a significant effect for group on the 8 mood variables from the MAACL and the ECS, F(8, 35) = 7.50, p<0.0001 (Wilks' criterion). Similarly, a one-way (group) MANOVA performed on the 5 cognitive variables from the BTQ and the ECS was also significant, F(5, 38) = 45.91, p<0.0001. Table I reports the respective means, t values, and significance levels. To summarize, bulimics received higher scores on self-schema for weight and on salient beliefs regarding food and weight on the BTQ. In addition, bulimics endorsed higher levels of anxiety, depression, and hostility on the MAACL. However, nonbulimics scored higher on positive affect. The groups did not differ significantly on the sensationseeking variable. On the ECS (with data from the binge-weight control cycle removed), bulimics endorsed higher levels o f anxiety, depression, and hostility. Finally, bulimics' scores were higher on self-schema for weight and salient beliefs.
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Table I . - BTQ, MAACL, and ECS variable means Group means Variables BTQ Self-schema for weight Self-efficacy regarding dieting Salient beliefs regarding food and weight MAACL Anxiety Depression Hostility Positive effect Sensation seeking ECS Anxiety Depression Hostility Self-schema for weight Salient beliefs regarding food and weight
Bulimic
Nonbulimic
t
4.55 (0.44)
2.64 (0.73)
10.50"*
4.03 (0.35)
3.83 (0.27)
2.06*
3.81 (0.61)
1.58 (0.31)
15.21"*
0.42 0.36 0.18 0.16 0.38
(0.24) (0.28) (0.13) (0.14) (0.12)
0.10 (0.12) 0.08 (0.12) 0.04 (0.05) 0.37 (0.29) 0.44 (0.16)
5.78** 4.33** 4.73** 2.98** 1.43
2.56 2.46 2.27 4.02
(0.74) (0.92) (0.73) (0.86)
1.71 (0.42) 1.44 (0.37) 1.53 (0.35) 1.61 (0.61)
4.70** 4.81"* 4.28** 10.75"*
1.08 (0.21)
8.70**
3.39 (1.23)
Note. Higher numbers indicate a greater frequency or more extreme responses with the exception of less self-efficacy regarding dieting. Standard deviations are in parentheses. *p < 0.05; **p < 0.01. Comparisonofvariablesduringthebulimiccycleandatbaseline. The 22 bulimic subjects recorded 31 binges, with a modal number of 1 binge. Each subject binged at least once. For subjects who engaged in more than 1 binge, their data were averaged for subsequent analyses. It should be noted that, during the study, the bulimic subjects reported fewer binges than they had during the initial screening interview, most likely due to the inhibitory effects of self-monitoring. Twelve of the binges were followed by exercising, whereas 5 were followed by fasting or restriction of caloric intake. Episodes of vomiting followed 5 of the binge episodes, and the use of laxatives followed 3. Finally, the combination of exercising and restricting caloric intake followed 2 o f the binges. Because most of the subjects engaged in other compensatory behavior besides vomiting or using laxatives, the terms compensatory behavior or weightcontrol technique will be used rather than purging. The average length of the binges during the study was 37 minutes. Two subjects binged but did not engage in any compensatory behavior. In addition, two other subjects each recorded 2 binges but only one compensatory behavior. Therefore, means for "after the compensatory behavior" f r o m subjects who provided data were substituted for the missing data to allow analysis of the data. Because the m o o d and cognitive factors were conceptualized as different entities, two separate one-way (stage of the bulimic cycle) M A N O V A s with repeated measures on stage were performed for the cognitive and m o o d variables. The 6 stages of the bulimic cycle were as follows: baseline score, which was a separate mean for each subject of ECS data at all time points excluding measures completed during the bulimic cycle; before the binge; beginning o f the binge; middle of the binge; after the binge; and after the compensatory behavior. A one-way (stage) M A N O V A with repeated
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measures was performed on the data from the 3 mood variables, F(15, 7)=22.36, p<0.001 (Wilks' criterion). A one-way (stage) MANOVA with repeated measures on the 6 stages was also found to be significant for the 2 cognitive variables, F(10, 12) = 5.78, p<0.003. Eighteen follow-up one-way (stage) MANOVAs with repeated measures on 2 stages for the mood and cognitive variables were conducted as follows: the baseline data were compared with each of the 5 stages of the bulimic cycle to determine possible maintenance factors. In addition, each stage was compared with its subsequent stage to determine changes over the cycle. To simplify the presentation of the results, only significant findings will be mentioned in the following sections. For the mood variables, "baseline" was significantly different from all of the following stages: "before the binge," F(3, 19) = 3.70, p<0.03; "beginning of the binge," F(3, 19) = 4.20, p <0.02; "middle of the binge," F(3, 19) = 7.58, p<0.002; "after the binge," F(3, 19)= 14.94, p<0.001; and "after the compensatory behavior," F(3, 19)= 6.46, p<0.003. Comparing the mood variables across stage, only "after the binge" versus "after the compensatory behavior" was significant, F(3, 19)= 6.66,/~0.003. To probe the significant MANOVAs, separate one-way (stage) analyses of variance (ANOVA) with repeated measures on 2 stages were conducted. Table II contains the means and comparisons of the emotions and cognitions at the different stages of the bulimic cycle. In terms of anxiety, most of the subsequent stages were higher than "baseline:" "before the binge," F(1,21) = 4.91, p<0.04; "beginning of the binge," F(1, 21)= 8.21,/~0.01; "middle of the binge," F(1, 21)= 8.23, p<0.01; and "after the binge," F(1, 21) = 13.25, p<0.002. Finally, anxiety "after the binge" was significantly higher than "after the compensatory behavior," F(1, 21)-- 12.41, p<0.002. In sum, these analyses indicated that subjects experienced more anxiety before, during, and after the binge than at baseline. However, anxiety decreased to baseline levels after subjects engaged in a weight-control technique. When we examined depression, a number of mean scores were significantly higher than "baseline": "before the binge," F(1, 21)= 11.05, p<0.004; "beginning of the binge," F(1, 21)=7.13, p<0.02; "middle of the binge," F(1, 21)=20.49, p<0.0002; "after the binge," F(1,2 l) = 42.77,/~0.0001; and "after the compensatory behavior," F(1, 21)= 8.79,/~0.008. Finally, the mean for depression "after the binge" was significantly higher than the "after the compensatory behavior" mean, F(1, 21) = 10.75, p<0.004. That is, subjects experienced more depression throughout all stages of the cycle compared to baseline, with a significant decrease after the compensatory behavior. However, depression was not reduced to baseline levels. All of the subsequent means for hostility were higher than "baseline": "before the binge," F(I, 21) = 8.21, p(0.01; "beginning of the binge," F (1, 21) = 7.98,/~0.02; "middle of the binge," F(1,2 l) = 20.28, p<0.0002; "after the binge," F(1,21) -- 33.11, /~0.0001; and "after the compensatory behavior," F(1, 21)--7.62, p<0.02. Finally, hostility scores "after the binge" were significantly greater than scores "after the compensatory behavior," F(1, 21)= 6.23,/~0.03. Like the scores for depression, levels of hostility were elevated throughout all of the stages of the cycle and decreased after the compensatory behavior, but not to baseline levels. In terms of the cognitive variables, a one-way (stage) MANOVA with repeated measures on "baseline" versus "before the binge" was significant, F(2, 20)= 4.01, p<0.03. "Baseline" versus "after the binge" was significant, F(2, 20) = 17.62, p<0.001,
Emotions and cognitions
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Table III.-Variable means before meals and before binges Meal/Binge status Variables Anxiety Depression Hostility SSW SBFW
Pre-meal
Pre-binge
2.60 (0.75) 2.34 (1.00) 2.24 (0.87) 3.79 (1.02) 3.26 (1.31)
2.94 (1.19) 3.10 (1.08) 2.84 (1.22) 4.25 (0.88) 3.89 (1.27)
F 2.64 16.01"* 5.78* 9.45** 9.86**
Note. Standard deviations are in parentheses. SSW = self-schema for weight. SBFW = salient beliefs regarding food and weight. *p < 0.05; **p < 0.01. as was "baseline" versus "after the compensatory behavior," F(2, 20) = 3.56, p<0.05. Comparing the cognitive variables across stage, only "after the binge" versus "after the compensatory behavior" was significant, F(2, 20) = 5.04, p<0.02. Where the M A N O V A s were significant for the cognitive variables, one-way ANOVAs with repeated measures on 2 stages were performed. For self-schema for weight, there was a trend for subjects to more strongly believe they were fat "before the binge" than at "baseline,"F(1,21) = 3.38,p<0.09. Subjects were also feeling fat more strongly "after the binge" than at "baseline,"F(1,21) = 35.64, p<0.0001, and "after the compensatory behavior," F(1, 21)= 7.74, p<0.02. In terms of salient beliefs regarding food and weight, the subjects' "before the binge" mean was significantly higher than "baseline," F(1,21) = 8.40, p<0.009. "After the binge" salient beliefs were also significantly stronger than at "baseline," F(1, 21)= 15.78, p<0.0007, as were "after the compensatory behavior" salient beliefs, F(1, 21)=6.44, p<0.02.
Additional analyses Analyses were also conducted to determine differences in the bulimics' moods and cognitions before meals and before binges. A one-way (pre-binge vs. pre-meal) M A N O V A with repeated measures was performed to compare the emotions before the binges with those before the meals, F(3, 18) = 5.06,p<0.01. To probe the significant M A N O V A , a one-way (pre-binge vs. pre-meal) A N O V A with repeated measures was performed on the anxiety variable, but was not found to be significant. However, subjects felt more depressed and hostile before a binge than before a meal. (See Table III for means and F values.) In terms of the cognitive variables, the one-way (pre-binge vs. pre-meal) M A N O V A was significant, F(2, 19) = 5.48, p <0.02. One-way ANOVAs indicated that subjects felt heavier and endorsed more salient beliefs regarding food and weight before a binge than before a meal. (See Table III for means and F values.) A one-way (post-binge vs. post-meal) M A N O V A with repeated measures was also performed to compare the emotions experienced after the meals to those experienced after the compensatory behaviors, F(3, 19)= 13.36,/9<0.001. Two post hoc one-way ANOVAs with repeated measures indicated that subjects reported more anxiety, more depression, and more hostility after a binge than after a meal. (See Table IV for means and F values.)
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325
Table IV. - Variable means after meals and after binges Meal/Binge status Variables
Post-meal
Post-binge
F
Anxiety Depression Hostility SSW SBFW
2.55 (0.89) 2.47 (1.02) 2.28 (0.82) 4.00 (0.87) 3.35 (1.22)
3.51 (1.32) 3.83 (1.24) 3.65 (1.19) 4.76 (0.53) 4.02 (1.43)
12.67"* 38.13'* 30.51"* 32.23** 16.23"*
Note. Standard deviations are in parentheses. SSW = self-schema for weight. SBFW = salient beliefs regarding food and weight. **p < 0.01.
A one-way (post-binge vs. post-meal) MANOVA with repeated measures was also found to be significant for the cognitive variables, F(2, 20)= 16.19, p<0.001. Two one-way ANOVAs with repeated measures revealed that subjects reported stronger cognitions regarding feeling fatter and stronger salient beliefs regarding food and weight after binges than after meals. (See Table IV for means and F values.) DISCUSSION When compared to baseline, the levels of all negative affect reported by the bulimic subjects were elevated in the 2 hours preceding the binge, at the beginning of the binge, in the middle of the binge, and after the binge. After engaging in weight-control behavior, subjects' hostility and depression remained elevated, although anxiety decreased to baseline levels. For all 3 mood variables, however, scores were significantly higher after the binge than after the compensatory behavior. The finding that negative mood was elevated prior to the binge has been well substantiated in the literature [1, 3, 5, 7, 9]. However, the fact that negative mood was elevated throughout the bulimic cycle was somewhat surprising, as it is generally believed that bingeing decreases negative affect. The research in this area, however, is divided, with 2 studies finding a reduction in negative mood [1, 12] and 1 study finding an increase in negative affect [7]. The hypothesized negative affect reducing effects might have occurred only at the very beginning of the binge and may not have been measured by asking subjects to report their feelings 5 minutes into the binge and at the middle of the binge. Hsu [6] found that dysphoric mood increased over the course o f the binge which supports this hypothesis. Self-monitoring may also have sensitized subjects to the negative aspects of their behavior. Although hostility and depression decreased after the compensatory behavior, they did not return to baseline levels. Some researchers have found that negative affect, particularly depression and guilt, remained high after the purge behavior as well [4, 5, 7). Other studies, however, have not supported this finding [7, 11, 12]. Differences in sample composition (e.g., severity o f bulimia, presence of personality disorders) and methodologies (e.g., types of measures used) may account for these inconsistencies. Although hostility and depression remained high after subjects engaged in compensatory behavior, anxiety levels decreased to baseline levels. Similar results were found in other studies as well [1, 8, 11]. In terms of cognitions, subjects had elevated levels of salient beliefs regarding food and weight, and there was a trend for bulimics to
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more strongly endorse cognitions regarding feeling heavy before a binge than at baseline. Distorted cognitions before a binge were reported in other studies as well [6, 9]. Because subjects reported stronger cognitions regarding feeling heavy and believed that they could not maintain a diet, these thoughts, along with elevated levels of negative affect, may have served to break their dietary restraint. Not surprisingly, subjects more strongly endorsed statements concerning feeling heavy and salient beliefs regarding food and weight after the binge than at baseline. However, the compensatory behavior did not significantly decrease the endorsement of salient beliefs regarding food and weight, whereas it decreased thoughts o f being overweight. Although it is impossible to determine causation, there were a few important similarities among the patterns of results for the emotions and cognitions data. Reductions found in the strength of subjects' feelings of anxiety might have been related to the reductions in the strength of thoughts regarding feeling fat after the compensatory behavior. In addition, the elevated levels of salient beliefs regarding food and weight might have been related to the elevated levels of depression and hostility following the compensatory behavior compared to baseline. Other analyses examined the differences in mood and cognitions before meals and before binges. Levels of anxiety were not significantly different between the two conditions, which is inconsistent with findings from the Elmore and de Castro [5] study. Levels of depression and hostility, however, were more elevated prior to a binge than to a meal. In addition, subjects felt heavier and endorsed more salient beliefs regarding food and weight prior to a binge than they did to a meal. Lingswiler et al. [9] also found that subjects endorsed more dichotomous cognitions regarding food before a binge than before other eating situations. A final set of analyses examined bulimics' responses following meals and binges. Not surprisingly, subjects reported feeling more anxiety, depression, and hostility after a binge than after a meal. Elmore and de Castro [5] found that bulimics were more depressed and anxious after a binge than after a meal as well. Subjects in this study also endorsed more salient beliefs regarding food and weight and statements regarding feeling fat after a binge than after a meal. Thus, increased levels of negative affect and dysfunctional cognitions after a binge may have resulted in the use of a weight-control technique to prevent weight gain and relieve negative affect. Several methodological concerns should be noted. First, subjects were asked to self-monitor their thoughts and feelings during the bulimic cycle, which may have produced some "reactivity." In fact, most subjects indicated that self-monitoring resulted in fewer binges. Second, giving the subjects only a few options by which to report their emotions and cognitions provided limited information and was not completely adequate in assessing subjects' thoughts and feelings during the bulimic cycle. Another limitation of this study was the heterogeneity of the bulimic sample in terms of the compensatory behavior methods used and previous treatment experience. Because the sample size was small, analyses on the different subgroups could not be done. Future studies should differentiate the bulimic population in terms of previous treatment experience, type of compensatory behavior technique used, and presence of Axis I and Axis II disorders. Because our sample was not in treatment and was mainly engaged in weight-control techniques other than purging, the subjects most likely represented a less severe variant of bulimia and, as a result, were different from most of the samples in other studies. However, a recent study [20] did not indicate
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any significant differences on a number of personality and Axis I disorders between purgers and nonpurgers. M o s t i m p o r t a n t l y , this s t u d y i l l u s t r a t e s the i m p o r t a n c e o f e x a m i n i n g c o g n i t i o n s a c r o s s s t a g e o f t h e b u l i m i c cycle. T h e p a t t e r n o f c h a n g e s o v e r t h e b u l i m i c cycle i n d i c a t e s a n i m p o r t a n t r o l e f o r c o g n i t i o n s in t h e p e r p e t u a t i o n o f t h e cycle a n d c a n p o s s i b l y e l u c i d a t e p o i n t s o f i n t e r v e n t i o n in t h e c o g n i t i v e - b e h a v i o r a l t r e a t m e n t o f bulimia. However, more research should be conducted with a broader scope of cognit i o n s t o m o r e c o m p l e t e l y u n d e r s t a n d b u l i m i c t h o u g h t s d u r i n g t h e b u l i m i c cycle.
REFERENCES 1. ABRAHAM SF, BEUMONT PJV. How patients describe bulimia or binge eating. PsycholMed 1982; 12: 625-635. 2. COOPER P J, BOWSKILL R. Dysphoric mood and overeating. Br JClin Psycho11986; 25: 155-156. 3. DAVIS R, FREEMAN F J, GARNER DM. A naturalistic investigation of eating behavior in bulimia nervosa. J Consult Clin Psychol 1988; 56: 273-279. 4. DAVIS R, FREEMAN R, SOLYOM L. Mood and food: an analysis of bulimic episodes. JPsychiatr Res 1985; 19: 331-335. 5. ELMORE DK, DE CASTRO JM. Self-rated moods and hunger in relation to spontaneous eating behavior in bulimics, recovered bulimics, and normals. Int JEating Disord 1990; 9: 179-190. 6. HSU LKG. Experiential aspects of Bulimia Nervosa: implications for cognitive behavioral therapy. Behav Mod 1990; 14: 50-65. 7. JOHNSON C, LARSON R. Bulimia: an analysis of moods and behavior. Psychosom Med 1982; 44: 341-351. 8. KAYE WH, GWIRTSMAN HE, GEORGE DT, WEISS SR, JIMERSON DC. Relationship of mood alterations to bingeing behaviour in bulimia. Br J Psychiatry 1986; 149: 479-485. 9. LINGSWlLER VM, CROWTHER JH, STEPHENS MAP. Affective and cognitive antecedents to eating episodes in bulimia and binge eating. Int JEating Disord 1989; 8: 533-539. 10. SCHLUNDT DG, JOHNSON WG, JARRELL MP. A naturalistic functional analysis of eating behavior in bulimia and obesity. Adv Behav Res Ther 1985; 7: 149-162. 11. STEINBERG S, TOBIN D, JOHNSON C. The role of bulimic behaviors in affect regulation: different functions for different patient subgroups? Int J Eating Disord 1990; 9:51-55. 12. COOPER JL, MORRISON TL, BIGMAN OL, ABRAMOWlTZ SI, LEVIN S, KRENER P. Mood changes and affective disorder in the bulimic binge-purge cycle. Int JEating Disord 1988; 7: 469-474. 13. ROSEN JC, LEITENBERG H, FONDACARO KM, GROSS J, WILLMUTH M. Standardized test meals in the assessment of eating behaviors in bulimia nervosa: consumption of feared foods when vomiting is prevented. Int J Eating Disord 1985; 4: 59-70. 14. THELEN MH, FARMER J, WONDERLICH S, SMITH M. A revision of the Bulimia Test: The BULIT-R. Psychol Assess: J Consult Clin Psychol 1991; 3:119-124. 15. Diagn•stic and Statistica• Manua•• Third E dn-Revised. W ashingt •n• DC : American Psychiatric Ass•ciation, 1986. 16. Metropolitan height and weight tables for adults. New York: Metropolitan Life Insurance Company, Health and Safety Division, 1983. 17. MORENO AB, THELEN MH. Parental factors related to Bulimia Nervosa. Addict Behav 1993; 18: 681-689. 18. PHELEN PW. Cognitive correlates of bulimia: the Bulimic Thoughts Questionnaire. Int J Eating Disord 1987; 6: 593-607. 19. ZUCKERMAN M' L UBIN B' RINCK CM" C°nstructi°n ° f new scales f °r the Multiple Affect Adjective Check List. JBehav Assess 1983; 5: 119-129. 20. WALTERS EE, NEALE MC, EAVES L J, HEATH AC, KESSLER RC, KENDLER KS. Bulimia nervosa: a population-based study of purgers versus nonpurgers. IntJEatingDisord 1993; 13: 265-272.
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APPENDIX ECS Date: _
_
Time:
AM/PM
Did you have a snack, a meal, or a binge in the past two h o u r s ? If so, indicate which one(s) 1. Indicate the emotion or m o o d that you are feeling most strongly right now: 2. Indicate the strongest t h o u g h t that you are having right now: For each statement below, please fill in one o f the following n u m b e r s concerning how strongly you are experiencing the following feelings or thoughts right now. 1
2
3
4
5
not at all
slightly
somewhat
quite a bit
very m u c h
1. I feel nervous _ _ 2. I'm so fat _ _ 3. I feel sad _ _ 4. I am a t t r a c t i v e _ 5. I feel disgusted 6. I always fail on diets; why even try _ _ 7. I feel tense _ _ 8. I wish I were thinner _ _ 9. I feel lost _ _ 10. I like the way I look 11. I feel disagreeable 12. I'm not worth anything if I am fat Was this questionnaire completed at the indicated time (or within 5 minutes on either side)? (circle one).
YES N O
I f no, please try to remember to complete the next ones at the indicated times because the
information is m u c h more accurate that way.