- Email: [email protected]
Health-related intrusive thoughts
Journal
HEALTH-RELATED
of Psychosomoric
Research, Vol. 38, No. 3, pp. 20%215, 1994 Copyright 0 1994 Ekvier Science Ltd Printed in Great Britain. All rights reserved 0022-3999/94 16.00 + .30
INTRUSIVE THOUGHTS
MARK H. FREESTON,* FABIEN GAGNON,~$ ROBERT LADOUCEUR,* NICOLE THIBODEAU,~ H~L&NE LETARTE* and JO&E RHI?AUME* (Received 26 April 1993; accepted in revisedform
11 September
1993)
Abstract-Two studies address the prevalence, concomitants, and appraisal of health-related intrusive thoughts. Eighty-three percent of adults (N= 6.58) in waiting rooms of two general hospitals reported at least one intrusive thought during the preceding month and 75.0% of patients and 55.5% of people accompanying them reported a health-related intrusive thought in the same period. The intrusions were associated with anxious and depressive symptoms. Health related intrusive thoughts were reported by 61% of a sample of university students (N = 608) and were the most frequent intrusive thought among 19.9% of the students. First, triggering stimuli reported by the subjects were significant predictors of thought frequency, worry, removal difficulty, and effort used in removing the thought. Second, appraisals of high probability were significant predictors of high frequency, worry, and especially difficulty in removing the thought. Finally, perceived responsibility and disapproval of the thought were also significant predictors of thought frequency, worry, removal difficulty, effort used in removing the thought, and guilt. These data support the position that cognitive appraisal of intrusive thoughts is closely linked to the subjective experience of the thought: more extreme appraisals were associated with more troublesome thoughts. The clinical implications of these studies are discussed in terms of current models of hypochondriasis and health anxiety. FEAR and worry about serious or fatal illness is common in the general population among children [l-3], students [4], adults [5, 61 and the elderly [7]. Health worry has also been reported as equally common among out-patients and a control non-patient group [8]. It has also been associated with psychiatric status [8] and anxiety [9]. Health-related intrusive cognitions have been reported in a population with medical risk [lo] as well as in the general population [l l-141. However, the prevalence of health worries in Generalized Anxiety Disorder (GAD) is as yet unclear. Craske et al. [15] report that health worries constituted a significantly larger proportion of all worries in a GAD patient group (30.6%) than in a matched control group (2.2%). Shadick et al. [16] found that only 3.0% of GAD subjects reported illness, health or injury related worries while 25.0% of non-anxious subjects reported these worries. Finally, Sanderson and Barlow [17] found that only 14% of their GAD patients reported personal illness related worries. These studies identifying anxiety producing health-related cognitions in the general population, in patient samples, and in psychiatric samples are relevant to current models of hypochondriasis and health anxiety [18-201 or illness phobia [21, 221. Warwick [20] states that ‘Negative thoughts and images of a threat to health will
*Universitb Laval, Centre de Recherche, Ecole de Psychologie, Cite Universitare, Quebec, Canada GlK 7P4. TCentre Hospitalier de 1’UniversitC Laval, Dept Psychiatric, 2705 Boulevard Laurier, Sainte-Foy (Quebec), Canada GlV 4G2. IAuthor to whom correspondence should bc addressed. Some of this data was presented at the Annual Meeting of the Canadian Psychological Association, Quebec City, Quebec, June 1992 and at the 42nd Annual Meeting of the Canadian Psychiatric Association, Montreal, Quebec, September 1992.
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M. H. FREFSTON et al.
inevitably be associated with anxiety, which may in turn be associated with increased physiological arousal, a confirmatory cognitive bias in processing external information and a range of avoidant behaviors, designed to cope with the problem. In the cognitive behavioral formulation all these are identified as maintaining factors, which will exacerbate and prolong health concerns’ (p. 706). Two studies are presented here that examine health-related intrusive thoughts in two different populations. The goal of the first study was to establish the prevalence of health related intrusive thoughts among medical patients and their escorts and to examine whether intrusive thoughts are associated with psychopathology in this population. The second study considers particular characteristics of health-related intrusions, namely, the link between different appraisals of the intrusive cognition and its subjective experience.
STUDY
1
This study was conducted as a part of a larger study looking at symptoms of emotional disorders among hospital out-patients and escorts. It was hypothesized that patients would report more health related thoughts than the people accompanying them. Likewise, it was expected that people reporting health related intrusive thoughts would show more signs of psychopathology than those who did not. Method Subjects. Eight hundred and eighty-five people participated in a questionnaire study in waiting rooms of two University teaching hospitals. Seventy-two percent of the sample identified themselves as patients, the remaining 28% were escorts. The sociodemographic profile was similar for both escorts and patients: 63% were women and the mean age was 39.5 yr (SD = 14.0). Educational status was varied but generally high as the hospitals served the university area: 6% primary, 42% secondary, 26% junior college, and 25% university. The rate of mental health consultation was quite high: 13.5% were currently consulting and a further 14.7% had previously consulted a psychiatrist, psychologist, or social worker. Due to random allocation of questionnaire combinations, 658 subjects completed the Cognitive Intrusions Questionnaire (CIQ [23]) and so their responses were available for analysis. Insrrumenrs. The principal instrument used in this study was the Cognitive Intrusions Questionnaire that asked subjects whether in the last month they had experienced intrusive thoughts, images, or impulses on six proposed themes (health, embarrassing situations, unacceptable sexual behavior, aggressive behavior, accidents or fatal illness occurring to friends or loved ones). Subjects could also indicate a seventh personal theme. Subjects were then asked to choose the most frequent intrusion. They then evaluated the thought on thirteen different items and answered ten questions on strategies used when the thought occurred. The twenty-three questions used 9 point likert-type scales. We have used the CIQ extensively in both clinical and nonclinical samples and have demonstrated adequate reliability and validity
1231. Subjects also received a selection of the following questionnaires. There were two measures of negative mood and accompanying somatic symptoms, namely, the twenty-one-item Beck Anxiety Inventory [24,25] and the abridged thirteen-item version of the Beck Depression Inventory [26, 271. There were also two 20item measures of irrational beliefs, namely, the Inventory of Beliefs Related to Obsessions [28] and the Belief Scale [29, 301 and a sixteen item measure of worry, the Penn State Worry Questionnaire [31, 321. Finally, a measure of obsessive-compulsive symptoms was also distributed, the Padua Inventory, a sixtyitem inventory measuring washing, checking, loss of control of mental events, and impulses [33, 241. Questionnaires were organized in blocks of approximately equal length. Procedure. Each subject was invited to participate in a study on thoughts and actions often reported by people. Subjects who agreed to participate received an envelope containing a brochure consisting of an explanatory letter, seven sociodemographic questions (sex, age, education, patient status, nationality, and current or past menral health consultation), and several questionnaires. People that were called by the doctor or nurse before completing the questionnaires were given the option of placing them in the collection box or completing them at home in which case they were given stamps and an address label.
Health-related
thoughts
Three out of four subjects received the CIQ. The combination determined for each subject.
205
and order of questionnaires
were randomly
Results Presence of health related thoughts. Eighty-three percent of the out-patient sample reported at least one intrusive thought in the last month. The frequencies of thoughts reported by patients and escorts are reported in Table I. Once Bonferroni adjustments were applied to control for type I error, health related thoughts were more prevalent among patients (75.0%) than among escorts (55.2%) (Ch? = 24.5, p < 0.0001) as were thoughts related to embarrassing situations (45.8% vs 31.5%, Chi2 = 9.90, p < 0.001). No differences were found for other thoughts. Neither sex, educational status, nor history of mental health consultation influenced the report of health related intrusive thoughts in the last month. Groups were formed by selecting patients not having health related thoughts, escorts not having health related thoughts, escorts reporting health related thoughts, and patients reporting thoughts. Analyses of variance (Thought Presence x Status) were conducted for each of the measures of psychopathological symptoms (Table II). The exact group size varied according to the questionnaire due to the random allocation of questionnaire combinations to subjects. Subjects reporting health related thoughts were more anxious (F(1, 263) = 12.13, p < O.OOl), depressed (F(l,267) = 12.38, p < 0.001) and worried (F(1, 104) = 5.08, p < 0.05) than subjects not reporting such thoughts, although both groups scored in the normal range. The interactions were not significant. However, for obsessivecompulsive symptoms, scores both the thought effect (F( 1,258) = 6.10, p < 0.01) and the interaction (F(1, 258) = 7.52, p < 0.01) were significant. The interaction was broken down into simple main effects that revealed that patients with health related thoughts reported more obsessivecompulsive symptoms than patients without health related thoughts (F(1, 258) = 22.67, p < 0.0001). Further, patients with health related thoughts reported more obsessivecompulsive symptoms than escorts reporting thoughts (F(1, 258) = 5.44, p < 0.05). Non-significant results were obtained with both measures of irrational beliefs. The results confirm that health related thoughts are associated with higher anxiety, depression, and the tendency to worry. Among patients, health related thoughts were associated with more obsessivecompulsive symptoms. TABLEI.-INTRUWETHOUGHTSREPORTED BY PATIENTSAND ESCORTSACCORDINGTOTHETHEME
% Reporting
Health* Embarrassment* Sexual activity Aggression Illness (someone Accident Other
*p -=c0.001.
close)
Escorts
Patients
55.5 31.5 14.2 31.9 41.9 28.0 24.4
75.0 45.8 19.4 35.4 31.4 23.1 27. I
M. H. FREESTON et al.
206
TABLE II.-MEANS AND STANDARDDEVIATIONS OF THREEMEASURES OF PSYCHOPATHOLOGY FORESCORTS AND PATIENT.9 Thought absent Escorts Anxiety N
M SD
Depression N M SD Worry N
M SD
Patients
Thought present Escorts
Patients
38 5.5 5.4
41 6.2 6.3
33 8.1 5.1
146 10.3 7.5
39 3.5 3.1
51 2.0 2.6
36 4.7 4.4
145 5.9 6.2
14 37.5 10.0
19 39.8 8.0
20 45.9 9.1
55 44.6 10.2
22 42.3 25.8
46 29.8 20.2
41 41.1 23.1
147 51.8 30.4
oc
N M SD
Health related thoughts named as most frequent. The group of subjects reporting that their most frequent thoughts were health related were compared with subjects naming other thoughts as the most frequent. Significantly more patients than escorts (48.2 vs 37.9%) named health related thoughts as the most frequent (Chi* = 4.4, p < 0.05). However, although 5.0% of escorts and 10.0% of patients named a relative’s illness as the most frequent thought, the difference was not significant. No differences were found for sex or current or past psychiatric status. Discussion Health related intrusive thoughts are highly prevalent among subjects recruited in a hospital waiting room setting. The hospital setting may have influenced the salience of health related thoughts, thus increasing the liklihood of them being named as the most frequent thought. This is supported by the fact that although less escorts than patients named health related thoughts, a sizeable proportion still did so whereas few named thoughts about relatives. While the setting may partially explain reporting of health related thoughts, the alternative is that health problems or perceptions of potential health problems among designated patients result in intrusive thoughts on health related topics. The observation that three out of four patients reported such thoughts certainly provides a large pool of health related cognition that may become troublesome for some people. Current or past history of mental health consultation was not related to reporting health related thoughts but current severity of psychopathological symptoms was involved. Both patients and escorts reporting health related thoughts were more anxious, depressed, and worried. In particular patients with health related thoughts reported more obsessive compulsive symptoms than patients without thoughts, and
Health-related more symptoms than escorts with thoughts. to more psychological distress, particularly
thoughts Thus health related thoughts among patients.
STUDY
207 were related
2
The present study considers health related cognitive intrusions in a large student sample. Despite the obvious convenience aspects of this type of sample, health-related cognitive intrusions may be particularly pertinent in this population in as much as health-related cognitive intrusions are related to, or are precursors of, hypochondriacal complaints and health anxiety. Hypochondriacal complaints have been identified as a self-handicapping strategy among university students in a manipulation of an evaluation situation [35]. Further, in the university context, medical reasons are among the most frequent motives for according delays, special consideration, and withdrawal without failure and so health-related intrusions may have particular salience. The principal objective of the second study is to look at particular characteristics of these intrusions, in particular, the link between different appraisals of the intrusive cognition and its subjective experience. An appraisal model developed by Carr [36] states that threat is the product of subjective probability and subjective cost and has been successfully applied to various anxiety disorders. Carr [36] defines cost as ‘the subjective unpleasantness of an anticipated event’ (p. 316). For this study, probability was defined as the degree of belief that the thought content (current or future health problem) will occur, and cost was defined as the degree of perceived responsibility if the thought content happens and the disapproval that having the thought engendered. It was postulated that dimensions such as thought frequency, worry, difficulty in removal, avoidance of triggering situations, and effort used in removing the thought will be related to the level of perceived threat. As models of health anxiety suggest that both bodily sensations and illness and external events (e.g. information, news items, illness involving others) may trigger thoughts and increase salience, it is important to enter the trigger variable into the regression equation first and thus partial out its influence before testing the relationship between threat and the other variables. The data analytic strategy chosen was hierarchical regression analysis [37] which allows a predetermined sequence of variables to be entered in turn, provides covariate control, and tests specific hypotheses. The study was conducted on archival data on a sample of students who had participated in a screening of general intrusive thoughts as a pre-selection for further experiments in information processing and intrusive thoughts. It was hypothesized that higher perceived threat would predict greater frequency, worry, guilt, difficulty and effort in removing the thought, etc. It was further hypothesized that the frequency of triggers would predict greater disturbance. Method Subjects. Two-hundred
and sixty-five university students were recruited in summer courses in various faculties. A further 343 students were recruited in music appreciation courses frequented by students from all faculties. The composition of the samples did not differ in terms of sex. The samples were combined and the final sample (N = 608) was 52% women. Twenty-one faculties or schools were represented. The mean age was 25.1 yr, (SD = 6.51).
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M. H. FREESTON et al. TABLE ~~~.-~NTRUSI~ETHOUGHT~ANDMOSTFREQ~ENT~OUGHTREPORTED
BYMENAND
WOMENACCORDINGTOTHETHEME
% Reporting
Health Embarrassment Sexual activity Aggression Illness (someone Accident Other *p < 0.05;
close)
Women
Men
64.6 62.1 24.8 56.8 42.6 45.8 22.3
54.5 63.0 34.5 58.1 21.5 33.8 25.44
% Most frequent x2 6.37+ < 1 6.78** < 1 15.60** 8.33** < 1
Women
Men
21.2 25.2 2.3 14.2 10.9 19.9 6.3
19.6 24.3 8.3 25.0 1.6 9.7 5.4
**p < 0.01.
Procedure. The subjects were asked to complete a questionnaire on unpleasant thoughts. A research assistant explained the goal of the study, provided a definition of unpleasant thoughts, explained the procedure, and assured confidentiality. Informed consent signatures were obtained and debriefing was offered. The procedure took about twenty minutes depending on the size of the group. Group size varied from 22 to 175.
Results Themes reported. The percentage of participants reporting each of the thoughts is presented in Table III. Relative to other thoughts, health related thoughts were among the three most commonly reported thoughts for both men and women along with thoughts about embarrassing situations and verbal aggression, all of which were reported by at least 50% of the sample (Table III). Note that significantly more women than men reported thoughts about their own health and about illness and accidents among loved ones whereas more men than women reported thoughts about verbal aggression and personally unacceptable sexual activity. When participants were asked to name the most frequent thought, 21.2% of women and 19.6% of men named health related thoughts. The pattern of most frequent thoughts was significantly different between men and women (Chi* = 30.5, p < 0.0001) with major differences (> 10%) on verbal aggression (more men than women) and accidents (more women than men). Comparison with hospital sample. The number of students reporting health related thoughts (59.7%) was compared with the number of out-patients and escorts from the first study who reported such thoughts (68.3%). Significantly more subjects in the out-patient sample reported health-related intrusive thoughts (Chi* = 8.10, p < 0.01). However, when the students were compared with the escorts alone (55.2%), there was no significant difference. The same comparison was made for the most frequent thought. Significantly more subjects in the out-patient sample named the healthrelated thought as the most frequent (44.2%) compared to 19.9% of students (Chi* = 58.95, p < 0.0001). However, when the students were compared to escorts alone, the difference remained significant (Chi* = 23.94, p < 0.0001). Thus, although escorts were no more likely to report health-related intrusive thoughts than students, they were more likely to name them as the most frequent. Regression analyses. One hundred and twenty-one participants (sixty-six women and fifty-five men) reporting health related thoughts as the most frequent intrusive
Health-related
thoughts
209
thought. Previous work has found differences between men and women on several dimensions of intrusive thoughts [23, 30, 341. Exploratory tests confirmed these differences so sex was entered first as a covariable in all subsequent equations. Five steps were used in the regression analysis (Table IV): (1) sex; (2) triggers; (3) probability; (4) cost (responsibility and disapproval); (5) threat (Probability x Cost). The complete models explained 26% of thought frequency variance, 41% of worry, 42% of removal difficulty, 51% of guilt, 12% of avoidance, and 29% of effort. Shrinkage varied from 3 to 6%. Sex. Sex contributed significantly only to predicting worry in the subsequent regressions, women reporting more worry (7%). Triggers. The frequency of triggering stimuli accounted for 5% of frequency variance, 10% of worry, 4% of removal difficulty, 7% of effort, and 4% of avoidance. These results confirm the second hypothesis and support the decision to enter the triggers before testing the appraisal variables. Probability. The probability of the thought occurring accounted for 12% of frequency, 11% of worry, 4% of guilt and 18% of removal difficulty. Cost. The cost set (responsibility and disapproval) accounted for 7% of frequency, 11% of worry, 39% of guilt, 16% of removal difficulty and effort, and 6% of avoidance. Responsibility was a significant contributor to the set for worry (6%), removal difficulty (12%), and guilt (35%). Disapproval was a significant contributor for frequency (4%), worry (3%), removal (4%) effort (12%) and avoidance (5%). Threat. The interaction or threat term accounted for an additional 5% of worry and thought removal scores. The Probability x Responsibility was the only individual significant predictor in both cases. Note that when the threat term was added instead of the two previous sets of its components parts rather than after them, it was a significant contributor to frequency (7%), worry (15%) removal (26%), guilt (32%), effort (12%) and avoidance (5%). This simpler model explained between 5 and 14% less than the more complex model. In other words, the Probability x Cost interaction set alone was not such a strong predictor as the complete set (Probability, Cost, Probability x Cost) despite contributing significantly in all cases except avoidance. So although in general the Probability x Cost interaction was a better predictor than either probability or cost taken individually, the stronger (but less parsimonious model) includes probability, cost, and the interaction term, threat. Discussion The results show that health-related intrusive activity is very common in university students. A full 61% reported having health-related intrusive thoughts in the last month. Further, health-related thoughts were the most frequent intrusions for 21% of the student sample. There were differences between the samples: patients only reported more thoughts than the students, but both patients and escorts named the thought as the most frequent more often than the students. Thus the setting alone would not seem to account for the fact that more patients reported health related thoughts because escorts would also be influenced. However, it may be responsible for them being named as the most frequent: the hospital setting may make health related thoughts more salient among both patients and escorts. As predicted, the presence of triggers was associated with frequency of intrusions as well as worry, removal difficulty, effort in removing the thought and avoidance of
M. H. FREFSTON et al.
210
potential triggers. In fact stimuli were reported as triggering thoughts half the time. This study did not identify whether the triggers were interoceptive (e.g. internal body sensations) or exteroceptive (external triggering events such as conversations, news items, etc.). Further work should identify the nature of such triggers in health anxiety which may also have implications for treatment. The subjective probability of the thought actually occurring (i.e. a current or actual health problem) also contributed substantially to the prediction of all variables except guilt and avoidance, particularly removal difficulty. Probability appraisal is likely to TABLEIV.-HIERARCHICALREGRESSIONANALYSESPREDICTINGFREQUENCY,WORRY, REMOVAL DIFFICULTY,GUILT,EFFORT, AVOIDANCE, FROM APPRAISAL VARIABLES
Set
Sex Triggers Probability Evaluation Responsibility Disapproval Interaction Probability x Resp. Probability x Disap.
Sex Triggers Probability Evaluation Responsibility Disapproval Interaction Probability x Resp. Probability x Disap.
Sex Triggers Probability Evaluation Responsibility Disapproval Interaction Probability x Resp. Probability x Disap.
Sex Triggers Probability Evaluation Responsibility Disapproval Interaction Probability x Resp. Probability x Disap.
F Frequency 0.87 5.53* 16.19** 4.79*
t
B
SR2
2.35 4.02
0.22 0.37
5% 12%
1.88 2.52*
0.17 0.21
3% 4%
0.27 0.33 0.35
7% 10% 11%
2.73*+ 2.12’
0.23 0.17
6% 3%
2.84** 0.95
0.73 0.23
4% 0%
0.20 0.45
4% 18%
4.10** 2.74**
0.34 0.22
12% 4%
3.10** 0.47
0.79 0.11
5% 0%
0.23
4%
0.61 0.20
35% 4%
1.08
Worry 8.69** 14.32 16.43** 7.13**
4.40*
Removal difficulty 0.0 4.32* 25.01** 14.10**
-
4.87**
Guilt 3.87 2.22 5.53* 42.40** 8.22** 2.86 1.91
(Continued).
Health-related
211
thoughts
TABLE IV.-Conrind
Sex
Triggers Probability Evaluation Responsibility Disapproval Interaction Probability x Resp. Probability x Disap.
Sex Triggers Probability Evaluation Responsibility Disapproval Interaction Probability x Resp. Probability x Disap.
Effort 2.82
-
8.90** 1.13 11.37** 1.67 4.28:’
0.28
1%
0.15 0.37
4% 12%
2.12 Avoidance 0.09 5.14* 1.80 3.56 1.16 2.48*
0.21
4%
0.11 0.23
0% 5%
0.71 -
*p < 0.05;**p < 0.01. be directed by both dysfunctional assumptions and factual information or knowledge [20]. The present study suggests that health related intrusive phenomena will be easier to remove, less frequent, and provoke less worry if lower probabilities are assigned to the concern. There is clearly a need for medical personnel to provide accurate information and to correct dysfunctional assumptions in order to reduce the frequency and severity of health related intrusive thoughts. This result is coherent with intervention programs that reduce patient stress and anxiety by informing patients about upcoming medical procedures [38, 391. Note however that the preferred coping style of the individual may determine the ultimate success of this type of intervention [40]. Evaluation of personal responsibility and disapproval were also important predictors of guilt and difficulty removing the thought. Perceived personal responsibility may be based on life style issues such as diet, exercise, sexual practices, and consumption of cigarettes, alcohol, and recreational drugs. It is not surprising that university students in the North American context in 1990 should be aware of their personal responsibility in preventive health care. It is virtually impossible to remain unaware of the media’s treatment of cholesterol, cigarettes, dietary fibre, AIDS, etc. Being aware of such issues and not acting on them in a responsible manner may lead to guilt and anxiety. Disapproval of the thought’s occurrence also accounted for some common variance. It is necessary to further investigate the beliefs of directing thought appraisal [28,41]. These may express beliefs such as ‘thinking about a possible illness can lead to it happening’ similar to the idea that routine examinations ‘might bring sicknes into being, not simply into sight’ ([42] p. 282) that was given by 23% of women in one study as a reason for not going to routine breast screening. The threat term when added later accounted for a smaller but still significant amount of variance in worry and thought removal difficulty scores. That is, high
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M. H. FREESTONet al.
appraisals of both responsibility and probability were associated with greater worry and difficulty in removing the thought. This suggests the general Threat = Probability x Cost model postulated by Carr [36] for OCD and since tested for other anxiety disorders may also apply for health-anxiety. GENERAL DISCUSSION
These results support other work on intrusive thoughts in general [l 1, 433451: health-related intrusive thoughts do have psychopathological concomitants and appraisal of thoughts is related to their subjective experience. Not surprisingly medical patients reported significantly more health related intrusive thoughts and those thoughts were more often identified as the most frequent intrusion among both patients and escorts than among university students. Although health related thoughts are very prevalent in unselected adult samples, these thoughts would become more frequent, or at least more salient, when triggering events or circumstances are present. Health problems, seeing the doctor, or simply being in a hospital setting would increase salience. The reason for consulting would also play a role: blood tests or X-rays as part of a regular check-up or for other non-threatening reasons would be different from tests due to a serious or unknown condition. Recording the reason for consultation would be enlightening in future studies as would doctor ratings of functional symptoms. The exact nature of the reported thoughts are as yet unknown. Some may be related to the highly specific and time-limited stress related intrusive thoughts studied by Horowitz et al. [lo] and Parkinson and Rachman [13]. Alternatively some thoughts may be perceived as ego-syntonic, probable, and as playing a self-protective role [46], and more closely resemble worrisome thoughts identified in GAD. Finally, some may be more ego-dystonic and senseless in nature and resemble obsessions [44, 471. The treatment implications may be different for each group according to the type of maintaining factors. For example worry-type thoughts may respond to stimulus control [48] whereas more obsessive thoughts would require exposure. The clinical implications of these results are perhaps best considered in the light of the literature on OCD treatment and may apply most to disease phobias, obsessional fears about illness and the ‘subgroup of hypochondriacal patients who are closer to the anxiety disorders in general and to OCD in particular’ ([49] p. 799). Current models of OCD postulate a continuum between normal intrusive thoughts and clinical obsessions [41,50] where appraisal determines both the degree of discomfort, neutralizing activity, and avoidance. Ultimately neutralizing and avoidance lead to repeated thoughts that are evaluated ever more catastrophically and are increasingly difficult to remove. The health-related intrusions in the present study would correspond to one pole of a similar continuum in health-anxiety. In line with the cognitive components of Warwick’s and Salkovskis’ [lS, 191 model of health anxiety, appraisal has been shown to be substantially related to removal difficulty, worry, and guilt associated with intrusions, and to a lesser extent to thought frequency, effort, and avoidance. Providing appropriate corrective information may change appraisals and hence reduce distress, avoidance, and subsequent thoughts. As Warwick and Salkovskis [51,52] have highlighted, the type of information and its presentation are crucial so as not to (a) increase doubt by vague and poorly understood information, (b)
h-related thoughts
213
become part of a cycle of reassurance that brings about short term relief but ultimately reinforces the health anxiety. The second study suggests that both the probability and responsibility dimensions should be addressed. In some cases it may be necessary to downplay the role of lifestyle factors or at least put them in perspective compared to other etiological factors for people who take excessive responsibility. Likewise more general beliefs placing undue weight on the thought’s occurrence should also be corrected by normalizing the experience so the thought itself does not become a cause of concern. We [53] currently use such base rate information on intrusions in the treatment of obsessional thoughts e.g. ‘99% of people report unpleasant thoughts with similar themes, having the thoughts is a normal experience, the degree of discomfort and the use of particular thoughts and behaviors in dealing with the thoughts is what needs attention’. Finally, for more severe cases where the psychological disturbance dominates, exposure to relevant exteroceptive and interoceptive triggers while preventing avoidant anxiety-reducing strategies such as reassurance seeking will allow habituation and provide a powerful source of new information to change appraisal. We have ourselves successfully treated patients with this approach [53] and Logsdail et al. [54] report a series of seven patients with severe AIDS related preoccupations treated by similar methods. Finally, this research highlights the presence of psychopathological symptoms in unselected outpatient samples and further shows that reported health-related intrusions may be a useful marker. Routine questioning about cognitive events related to functional somatic symptoms may help medical personnel better determine which patients have accompanying or predominant health-anxiety [20]. In this case appropriate psychological evaluation may suggest psychological intervention either as an additional strategy, or, in severe cases of health anxiety not related to medical conditions, as the strategy of choice. The appropriate psychometric devices remain to be identified, but rapid assessment instruments similar to those used in the present study are well adapted and easy to use. In conclusion, health-related intrusions are very prevalent among patients and escorts recruited in a hospital setting as well as among university students. These results support cognitive-behavioral models of hypochondriasis and health-anxiety and suggest that strategies being developed for the treatment of other anxiety disorders may be adapted to the specific features of health anxiety. Acknowledgemenrs-This study was supported by a grant from Les Fonds en recherche de Santk du Quebec. The study was completed while the first author was a holder of a studentship from the Medical Research Council of Canada. The authors wish to thank the staff and direction at l’H8pital St-Franqois d’Assise and le Centre Hospitalier de 1’UniversitC Lava1 for the collaboration in allowing and facilitating data collection.
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7. WI~OCKIPA. Worry as a phenomenon relevant to the elderly. Behav Ther 1988; 19: 369-379. 8. KELLNERR, ABBOTT P, PATHAK D, WINSLOW WW, OMLAND BE. Hypochondriacal beliefs and attitudes in family practice and psychiatric patients. Int J Psychiar Med 1983; 13: 127-139. 9. BYERSPH, ST-ONCEJL, ATKINSLA, PROKOPJA, GRANOJT. Self-disclosure, anxiety, and health worry in unscheduled outpatients. Psychological Bull 1988; 81: 31 l-318. JE, BILLINGJH, BORHANI N, BENFARIR. The stressful 10.HOROWITZMJ, SIMONN, HOLDENM, CONNETT impact of news of risk for premature heart disease. Psychosom Med 1983; 45: 3140. 11. CLARKDA, DE SILVAP. The nature of depressive and anxious, intrusive thoughts: Distinct or uniform phenomena? Behav Res Ther 1985; 23: 383-393. S. Intrusive thoughts: The effects of a uncontrived stress. Adv Behav Res Ther 12. PARKINXINL, RACHMAN 1981; 3: 111-118. L, RACHMANS. The nature of intrusive thoughts. Adv Behav Res Ther 1981; 3: 101-l 10. 13. PARKINSON 14. RACHMANS, DE SILVAP. Abnormal and normal obsess&s. Behav Res Ther 1978; 16:233-248. 15. CRASKEMC. RAPEERM, JACKELL, BARLOWDH. Qualitative dimensions of worry in DSM-1 11-R generalized anxiety disorder subjects and nonanxious-control. Behav Res Ther 1989; 27: 397402. TD. The nature of worrisome thoughts. Paper 16. SHADICKRN, ROEMERL, HOPKINSMB, BORKOVEC
17. 18. 19. 20. 21. 22. 23. 24. 25.
26. 27. 28. 29.
presented at the 25th Annual Convention of the Association for the Advancement of Behavior Therapy, New York, New York, November 1991. SANDERWNWC, BARLOWDH. A description of patients diagnosed with DSM-111-R generalized anxiety disorder. J Nerv Ment Dis 1990; 178: 588-591. WARWICKHMC, SALKOVSKIS PM. Hypochondriasis. In Cognitive Therapy in Clinical Practice (Edited by Scold J, WILLIAMSJMG, BECKAT), pp. 78-102. London: Routledge, 1989. WARWICKHMC, SALKOVSKIS PM. Hypochondriasis. Behav Res Ther 1990; 28: 105-117. WARWICKHMC. A cognitive-behavioral approach to hypochondriasis and health anxiety. J Psychosom Res 1989; 33: 705-7 11. MARKSIM. Fears, Phobia, and Rituals. Oxford: Oxford University Press, 1987. WARWICKHMC, MARKSIM. Behavioural treatment of illness and hypochondriasis: A pilot study of 17 cases. Br J Psychiatry 1988; 152:239-241. FREE~TON MH, LADOUCEUR R, LETARTEH, GAGNONF, THIBODEAU N. DPveloppemeni d’une mesure d’intrusions co&fives. [Development of a measure of intrusive cognitions] (In prep.). BECKAT, EPSTEINN, BROWNG, STEERRA. An inventory for measuring clinical anxiety: Psychometric properties. J Consult Clin Psycho1 1988; 56: 893-897. FREESTON MH, LADOUCEUR R, GAGNON F, THIBODEAU N, RH~AUME J. L’inventaire d’Anxitt8 de Beck: Propriktts psychometriques d’une traduction franGaise. [The Beck Anxiety Inventory: Psychometric properties of a French translation]. L’Enciphale. (In press). BECKAT, RUSHAJ, SHAWBF, EMERY G. Cognitive Therapy of Depression. New York: Guilford, 1979. BOURQUE P, BEAUDETTE D. Etude psychom&ique du questionnaire de Beck aup& d’une tchantillon d’btudiants universitaires francophones. Can J Behav Sci 1982; 14:211-218. FREESTONMH, LADOUCEURR, THIB~DEAUN, GAGNONF. Beliefs about obsessional thoughts. J Psychopath01 Behav Assess 1993; 15:l-21. MALOUFFJM, SCHUTTENS. Development and validation of a measure of irrational belief. J Consult
Clin Psycho1 1986; 54: 86CL862. MH, LADOUCEUR R, GAGNON F, THIBODEALI N. Translation and validation of a French30. FREESTON
Canadian version of the Malouff and Schutte Belief Scale. Unpublished manuscript, Universitt: Lava& 1991. TD. Development and validation of the Penn State 31. MEYERTJ, MILLERML, METZGERRL, BORKOVEC Worry Questionnaire. Behav Res Ther 1990; 28: 4871195. R, FREESTON MH, DUMONTJ, LETARTE H, RH~AUME J, GAGNON F, THIBODEAU N. Penn 32. LADOLJCEUR State Worry Questionnaire: Validity and reliability of a French translation. Can Psychology 1992; 33: 236. E. Obsessions and compulsions: The Padua Inventory. Behav Res Ther 1988; 26: 169-177. 33. SANAVIO MH, LADOUCEUR R, LE~ARTEH, R&AUME J, GAGNON F, THIBODEAU N. Invenraire de 34. FREESTON Padova: PropriPtCs psychomhtriques d’une traduction canadienne frangaise [Padua Inventory: Psycho-
metric properties of a French-Canadian
translation. (In prep.).
35. Smith TW, Snyder CR, Perkins SC. The self-serving function of hypochondriacal complain: Physical symptoms as self-handicapping strategies. J Person Sot Psycho1 1983; 4: 787-797.
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36. CARR AT. Compulsive neurosis: A review of the literature. Psychological Bull 1974; 81: 31 l-318. 31 COHEN J, COHEN P. Applied Multiple Analvsis _ Regression/Correlation _ ”for the Behavioral Sciences. Hillsdale: Erlbaum, 1983. interventions and coping with surgery. In Handbook of Psychology and 38 JOHNSON JE. Psychological Health (Edited by BAUM H, TAYLOR SE, SINGER JE) Vol. 4. Hillsdale: Laurence Erlbaum, 1983. intervention with surgical patients: Evaluation outcome. Adv 39 ROGERS M, REICH P. Psychological Psychosom Med 1986; 15: 23-50. 40 MILLER SM. To see or not to see: Cognitive informational styles in the coping process. In Learned Resourcefulness: On Coping Skills, Self-Control, and Adaptive Behavior (Edited by ROSENBAUMM). New York: Springer, 1990. 41 SALKOVSKISPM. Obsessions and compulsions. In Cognifive Therapy: A Clinical Casebook (Edited by SCOTT J, WILLIAMS JMG, BECK AT), pp. 5&77. New York: Croom Helm, 1989. 42. MACLEAN U, SINFIELD D, KLEIN S, HARNDEN B. Women who decline breast screening. J Epidemiol Comm Health 1984; 38: 278-283. 43. CLARK DA. Depressive, anxious and intrusive thoughts in psychiatric inpatients and outpatients. Behav Res Ther 1992; 30: 93-192. 44 FREE~TON MH, LAD~UCELJR R, THIBODEAU N, GAGNON F. Cognitive intrusions in a non-clinical population. II. Associations with depressive, anxious, and compulsive symptoms. Behav Res Ther 1992; 30: 263-271. 45. NILER ER, BECK SJ. The relationship among guilt, dysphoria, anxiety and obsessions in a normal population. Behav Res Ther 1989; 27: 213-220. 46. ROEMER L, BORKOVEC M, POSA S, LYONSFIELDS J. Generalized anxiety disorder in an analoaue population: The role of past trauma. Paper presented at the 25th Annual Convention of The Association for the Advancement of Behavior Therapy. New York. New York. November 1991. 47. FREESTONMH, LADOUCEUR R, GAGNON F, THIBODE& N. Intrusive thoughts, worry, and obsessions: Empirical and theoretical distinctions. In P. Salkovskis, Chair, Clinical and Non-clinical Intrusive Thoughts. Communication presented at the World Congress of Cognitive Therapy, Toronto, June 1992. 48. BORKOVECTD, WILKINXIN L, FOLENSBEER, LERMANC. Stimulus control applications to the treatment of worry. Behav Res Ther 1993; 21: 247-251. and obsessive compulsive disorder. Psychiar Clin N Am 1992; 15: 79149. BARSKY AJ. Hypochondriasis 801. problems: A cognitive-behavioural analysis. Behav Res Ther 50. SALKOVSKISPM. Obsessionallccmpulsive 1985; 23: 571-583. 51. WARWICK HMC, SALKOVSKISPM. Reassurance. Br Med J 1985; 290: 1028. health anxiety, and reassurance: A 52. SALKOVSKIS PM, WARWICK HMC. Morbid preoccupations, cognitive-behavioural approach to hypochodriasis. Behav Res Ther 1986; 24: 597-602. 53. LADOUCEUR R, FREESTON MH, GAGNON F, THIBODEAU N, DUMONT J. Idiographic considerations in the cognitive-behavioral treatment of obsessional thoughts. J Behav Ther Exp Psychiafry (In press). 54. LOGSDAIL S, LOVELL K, WARWICK H, MARKS I. Behavioural treatment of AIDS-focused illness phobia. Br J Psychiatry 1991; 159: 422425.
HEALTH-RELATED
of Psychosomoric
Research, Vol. 38, No. 3, pp. 20%215, 1994 Copyright 0 1994 Ekvier Science Ltd Printed in Great Britain. All rights reserved 0022-3999/94 16.00 + .30
INTRUSIVE THOUGHTS
MARK H. FREESTON,* FABIEN GAGNON,~$ ROBERT LADOUCEUR,* NICOLE THIBODEAU,~ H~L&NE LETARTE* and JO&E RHI?AUME* (Received 26 April 1993; accepted in revisedform
11 September
1993)
Abstract-Two studies address the prevalence, concomitants, and appraisal of health-related intrusive thoughts. Eighty-three percent of adults (N= 6.58) in waiting rooms of two general hospitals reported at least one intrusive thought during the preceding month and 75.0% of patients and 55.5% of people accompanying them reported a health-related intrusive thought in the same period. The intrusions were associated with anxious and depressive symptoms. Health related intrusive thoughts were reported by 61% of a sample of university students (N = 608) and were the most frequent intrusive thought among 19.9% of the students. First, triggering stimuli reported by the subjects were significant predictors of thought frequency, worry, removal difficulty, and effort used in removing the thought. Second, appraisals of high probability were significant predictors of high frequency, worry, and especially difficulty in removing the thought. Finally, perceived responsibility and disapproval of the thought were also significant predictors of thought frequency, worry, removal difficulty, effort used in removing the thought, and guilt. These data support the position that cognitive appraisal of intrusive thoughts is closely linked to the subjective experience of the thought: more extreme appraisals were associated with more troublesome thoughts. The clinical implications of these studies are discussed in terms of current models of hypochondriasis and health anxiety. FEAR and worry about serious or fatal illness is common in the general population among children [l-3], students [4], adults [5, 61 and the elderly [7]. Health worry has also been reported as equally common among out-patients and a control non-patient group [8]. It has also been associated with psychiatric status [8] and anxiety [9]. Health-related intrusive cognitions have been reported in a population with medical risk [lo] as well as in the general population [l l-141. However, the prevalence of health worries in Generalized Anxiety Disorder (GAD) is as yet unclear. Craske et al. [15] report that health worries constituted a significantly larger proportion of all worries in a GAD patient group (30.6%) than in a matched control group (2.2%). Shadick et al. [16] found that only 3.0% of GAD subjects reported illness, health or injury related worries while 25.0% of non-anxious subjects reported these worries. Finally, Sanderson and Barlow [17] found that only 14% of their GAD patients reported personal illness related worries. These studies identifying anxiety producing health-related cognitions in the general population, in patient samples, and in psychiatric samples are relevant to current models of hypochondriasis and health anxiety [18-201 or illness phobia [21, 221. Warwick [20] states that ‘Negative thoughts and images of a threat to health will
*Universitb Laval, Centre de Recherche, Ecole de Psychologie, Cite Universitare, Quebec, Canada GlK 7P4. TCentre Hospitalier de 1’UniversitC Laval, Dept Psychiatric, 2705 Boulevard Laurier, Sainte-Foy (Quebec), Canada GlV 4G2. IAuthor to whom correspondence should bc addressed. Some of this data was presented at the Annual Meeting of the Canadian Psychological Association, Quebec City, Quebec, June 1992 and at the 42nd Annual Meeting of the Canadian Psychiatric Association, Montreal, Quebec, September 1992.
203
204
M. H. FREFSTON et al.
inevitably be associated with anxiety, which may in turn be associated with increased physiological arousal, a confirmatory cognitive bias in processing external information and a range of avoidant behaviors, designed to cope with the problem. In the cognitive behavioral formulation all these are identified as maintaining factors, which will exacerbate and prolong health concerns’ (p. 706). Two studies are presented here that examine health-related intrusive thoughts in two different populations. The goal of the first study was to establish the prevalence of health related intrusive thoughts among medical patients and their escorts and to examine whether intrusive thoughts are associated with psychopathology in this population. The second study considers particular characteristics of health-related intrusions, namely, the link between different appraisals of the intrusive cognition and its subjective experience.
STUDY
1
This study was conducted as a part of a larger study looking at symptoms of emotional disorders among hospital out-patients and escorts. It was hypothesized that patients would report more health related thoughts than the people accompanying them. Likewise, it was expected that people reporting health related intrusive thoughts would show more signs of psychopathology than those who did not. Method Subjects. Eight hundred and eighty-five people participated in a questionnaire study in waiting rooms of two University teaching hospitals. Seventy-two percent of the sample identified themselves as patients, the remaining 28% were escorts. The sociodemographic profile was similar for both escorts and patients: 63% were women and the mean age was 39.5 yr (SD = 14.0). Educational status was varied but generally high as the hospitals served the university area: 6% primary, 42% secondary, 26% junior college, and 25% university. The rate of mental health consultation was quite high: 13.5% were currently consulting and a further 14.7% had previously consulted a psychiatrist, psychologist, or social worker. Due to random allocation of questionnaire combinations, 658 subjects completed the Cognitive Intrusions Questionnaire (CIQ [23]) and so their responses were available for analysis. Insrrumenrs. The principal instrument used in this study was the Cognitive Intrusions Questionnaire that asked subjects whether in the last month they had experienced intrusive thoughts, images, or impulses on six proposed themes (health, embarrassing situations, unacceptable sexual behavior, aggressive behavior, accidents or fatal illness occurring to friends or loved ones). Subjects could also indicate a seventh personal theme. Subjects were then asked to choose the most frequent intrusion. They then evaluated the thought on thirteen different items and answered ten questions on strategies used when the thought occurred. The twenty-three questions used 9 point likert-type scales. We have used the CIQ extensively in both clinical and nonclinical samples and have demonstrated adequate reliability and validity
1231. Subjects also received a selection of the following questionnaires. There were two measures of negative mood and accompanying somatic symptoms, namely, the twenty-one-item Beck Anxiety Inventory [24,25] and the abridged thirteen-item version of the Beck Depression Inventory [26, 271. There were also two 20item measures of irrational beliefs, namely, the Inventory of Beliefs Related to Obsessions [28] and the Belief Scale [29, 301 and a sixteen item measure of worry, the Penn State Worry Questionnaire [31, 321. Finally, a measure of obsessive-compulsive symptoms was also distributed, the Padua Inventory, a sixtyitem inventory measuring washing, checking, loss of control of mental events, and impulses [33, 241. Questionnaires were organized in blocks of approximately equal length. Procedure. Each subject was invited to participate in a study on thoughts and actions often reported by people. Subjects who agreed to participate received an envelope containing a brochure consisting of an explanatory letter, seven sociodemographic questions (sex, age, education, patient status, nationality, and current or past menral health consultation), and several questionnaires. People that were called by the doctor or nurse before completing the questionnaires were given the option of placing them in the collection box or completing them at home in which case they were given stamps and an address label.
Health-related
thoughts
Three out of four subjects received the CIQ. The combination determined for each subject.
205
and order of questionnaires
were randomly
Results Presence of health related thoughts. Eighty-three percent of the out-patient sample reported at least one intrusive thought in the last month. The frequencies of thoughts reported by patients and escorts are reported in Table I. Once Bonferroni adjustments were applied to control for type I error, health related thoughts were more prevalent among patients (75.0%) than among escorts (55.2%) (Ch? = 24.5, p < 0.0001) as were thoughts related to embarrassing situations (45.8% vs 31.5%, Chi2 = 9.90, p < 0.001). No differences were found for other thoughts. Neither sex, educational status, nor history of mental health consultation influenced the report of health related intrusive thoughts in the last month. Groups were formed by selecting patients not having health related thoughts, escorts not having health related thoughts, escorts reporting health related thoughts, and patients reporting thoughts. Analyses of variance (Thought Presence x Status) were conducted for each of the measures of psychopathological symptoms (Table II). The exact group size varied according to the questionnaire due to the random allocation of questionnaire combinations to subjects. Subjects reporting health related thoughts were more anxious (F(1, 263) = 12.13, p < O.OOl), depressed (F(l,267) = 12.38, p < 0.001) and worried (F(1, 104) = 5.08, p < 0.05) than subjects not reporting such thoughts, although both groups scored in the normal range. The interactions were not significant. However, for obsessivecompulsive symptoms, scores both the thought effect (F( 1,258) = 6.10, p < 0.01) and the interaction (F(1, 258) = 7.52, p < 0.01) were significant. The interaction was broken down into simple main effects that revealed that patients with health related thoughts reported more obsessivecompulsive symptoms than patients without health related thoughts (F(1, 258) = 22.67, p < 0.0001). Further, patients with health related thoughts reported more obsessivecompulsive symptoms than escorts reporting thoughts (F(1, 258) = 5.44, p < 0.05). Non-significant results were obtained with both measures of irrational beliefs. The results confirm that health related thoughts are associated with higher anxiety, depression, and the tendency to worry. Among patients, health related thoughts were associated with more obsessivecompulsive symptoms. TABLEI.-INTRUWETHOUGHTSREPORTED BY PATIENTSAND ESCORTSACCORDINGTOTHETHEME
% Reporting
Health* Embarrassment* Sexual activity Aggression Illness (someone Accident Other
*p -=c0.001.
close)
Escorts
Patients
55.5 31.5 14.2 31.9 41.9 28.0 24.4
75.0 45.8 19.4 35.4 31.4 23.1 27. I
M. H. FREESTON et al.
206
TABLE II.-MEANS AND STANDARDDEVIATIONS OF THREEMEASURES OF PSYCHOPATHOLOGY FORESCORTS AND PATIENT.9 Thought absent Escorts Anxiety N
M SD
Depression N M SD Worry N
M SD
Patients
Thought present Escorts
Patients
38 5.5 5.4
41 6.2 6.3
33 8.1 5.1
146 10.3 7.5
39 3.5 3.1
51 2.0 2.6
36 4.7 4.4
145 5.9 6.2
14 37.5 10.0
19 39.8 8.0
20 45.9 9.1
55 44.6 10.2
22 42.3 25.8
46 29.8 20.2
41 41.1 23.1
147 51.8 30.4
oc
N M SD
Health related thoughts named as most frequent. The group of subjects reporting that their most frequent thoughts were health related were compared with subjects naming other thoughts as the most frequent. Significantly more patients than escorts (48.2 vs 37.9%) named health related thoughts as the most frequent (Chi* = 4.4, p < 0.05). However, although 5.0% of escorts and 10.0% of patients named a relative’s illness as the most frequent thought, the difference was not significant. No differences were found for sex or current or past psychiatric status. Discussion Health related intrusive thoughts are highly prevalent among subjects recruited in a hospital waiting room setting. The hospital setting may have influenced the salience of health related thoughts, thus increasing the liklihood of them being named as the most frequent thought. This is supported by the fact that although less escorts than patients named health related thoughts, a sizeable proportion still did so whereas few named thoughts about relatives. While the setting may partially explain reporting of health related thoughts, the alternative is that health problems or perceptions of potential health problems among designated patients result in intrusive thoughts on health related topics. The observation that three out of four patients reported such thoughts certainly provides a large pool of health related cognition that may become troublesome for some people. Current or past history of mental health consultation was not related to reporting health related thoughts but current severity of psychopathological symptoms was involved. Both patients and escorts reporting health related thoughts were more anxious, depressed, and worried. In particular patients with health related thoughts reported more obsessive compulsive symptoms than patients without thoughts, and
Health-related more symptoms than escorts with thoughts. to more psychological distress, particularly
thoughts Thus health related thoughts among patients.
STUDY
207 were related
2
The present study considers health related cognitive intrusions in a large student sample. Despite the obvious convenience aspects of this type of sample, health-related cognitive intrusions may be particularly pertinent in this population in as much as health-related cognitive intrusions are related to, or are precursors of, hypochondriacal complaints and health anxiety. Hypochondriacal complaints have been identified as a self-handicapping strategy among university students in a manipulation of an evaluation situation [35]. Further, in the university context, medical reasons are among the most frequent motives for according delays, special consideration, and withdrawal without failure and so health-related intrusions may have particular salience. The principal objective of the second study is to look at particular characteristics of these intrusions, in particular, the link between different appraisals of the intrusive cognition and its subjective experience. An appraisal model developed by Carr [36] states that threat is the product of subjective probability and subjective cost and has been successfully applied to various anxiety disorders. Carr [36] defines cost as ‘the subjective unpleasantness of an anticipated event’ (p. 316). For this study, probability was defined as the degree of belief that the thought content (current or future health problem) will occur, and cost was defined as the degree of perceived responsibility if the thought content happens and the disapproval that having the thought engendered. It was postulated that dimensions such as thought frequency, worry, difficulty in removal, avoidance of triggering situations, and effort used in removing the thought will be related to the level of perceived threat. As models of health anxiety suggest that both bodily sensations and illness and external events (e.g. information, news items, illness involving others) may trigger thoughts and increase salience, it is important to enter the trigger variable into the regression equation first and thus partial out its influence before testing the relationship between threat and the other variables. The data analytic strategy chosen was hierarchical regression analysis [37] which allows a predetermined sequence of variables to be entered in turn, provides covariate control, and tests specific hypotheses. The study was conducted on archival data on a sample of students who had participated in a screening of general intrusive thoughts as a pre-selection for further experiments in information processing and intrusive thoughts. It was hypothesized that higher perceived threat would predict greater frequency, worry, guilt, difficulty and effort in removing the thought, etc. It was further hypothesized that the frequency of triggers would predict greater disturbance. Method Subjects. Two-hundred
and sixty-five university students were recruited in summer courses in various faculties. A further 343 students were recruited in music appreciation courses frequented by students from all faculties. The composition of the samples did not differ in terms of sex. The samples were combined and the final sample (N = 608) was 52% women. Twenty-one faculties or schools were represented. The mean age was 25.1 yr, (SD = 6.51).
208
M. H. FREESTON et al. TABLE ~~~.-~NTRUSI~ETHOUGHT~ANDMOSTFREQ~ENT~OUGHTREPORTED
BYMENAND
WOMENACCORDINGTOTHETHEME
% Reporting
Health Embarrassment Sexual activity Aggression Illness (someone Accident Other *p < 0.05;
close)
Women
Men
64.6 62.1 24.8 56.8 42.6 45.8 22.3
54.5 63.0 34.5 58.1 21.5 33.8 25.44
% Most frequent x2 6.37+ < 1 6.78** < 1 15.60** 8.33** < 1
Women
Men
21.2 25.2 2.3 14.2 10.9 19.9 6.3
19.6 24.3 8.3 25.0 1.6 9.7 5.4
**p < 0.01.
Procedure. The subjects were asked to complete a questionnaire on unpleasant thoughts. A research assistant explained the goal of the study, provided a definition of unpleasant thoughts, explained the procedure, and assured confidentiality. Informed consent signatures were obtained and debriefing was offered. The procedure took about twenty minutes depending on the size of the group. Group size varied from 22 to 175.
Results Themes reported. The percentage of participants reporting each of the thoughts is presented in Table III. Relative to other thoughts, health related thoughts were among the three most commonly reported thoughts for both men and women along with thoughts about embarrassing situations and verbal aggression, all of which were reported by at least 50% of the sample (Table III). Note that significantly more women than men reported thoughts about their own health and about illness and accidents among loved ones whereas more men than women reported thoughts about verbal aggression and personally unacceptable sexual activity. When participants were asked to name the most frequent thought, 21.2% of women and 19.6% of men named health related thoughts. The pattern of most frequent thoughts was significantly different between men and women (Chi* = 30.5, p < 0.0001) with major differences (> 10%) on verbal aggression (more men than women) and accidents (more women than men). Comparison with hospital sample. The number of students reporting health related thoughts (59.7%) was compared with the number of out-patients and escorts from the first study who reported such thoughts (68.3%). Significantly more subjects in the out-patient sample reported health-related intrusive thoughts (Chi* = 8.10, p < 0.01). However, when the students were compared with the escorts alone (55.2%), there was no significant difference. The same comparison was made for the most frequent thought. Significantly more subjects in the out-patient sample named the healthrelated thought as the most frequent (44.2%) compared to 19.9% of students (Chi* = 58.95, p < 0.0001). However, when the students were compared to escorts alone, the difference remained significant (Chi* = 23.94, p < 0.0001). Thus, although escorts were no more likely to report health-related intrusive thoughts than students, they were more likely to name them as the most frequent. Regression analyses. One hundred and twenty-one participants (sixty-six women and fifty-five men) reporting health related thoughts as the most frequent intrusive
Health-related
thoughts
209
thought. Previous work has found differences between men and women on several dimensions of intrusive thoughts [23, 30, 341. Exploratory tests confirmed these differences so sex was entered first as a covariable in all subsequent equations. Five steps were used in the regression analysis (Table IV): (1) sex; (2) triggers; (3) probability; (4) cost (responsibility and disapproval); (5) threat (Probability x Cost). The complete models explained 26% of thought frequency variance, 41% of worry, 42% of removal difficulty, 51% of guilt, 12% of avoidance, and 29% of effort. Shrinkage varied from 3 to 6%. Sex. Sex contributed significantly only to predicting worry in the subsequent regressions, women reporting more worry (7%). Triggers. The frequency of triggering stimuli accounted for 5% of frequency variance, 10% of worry, 4% of removal difficulty, 7% of effort, and 4% of avoidance. These results confirm the second hypothesis and support the decision to enter the triggers before testing the appraisal variables. Probability. The probability of the thought occurring accounted for 12% of frequency, 11% of worry, 4% of guilt and 18% of removal difficulty. Cost. The cost set (responsibility and disapproval) accounted for 7% of frequency, 11% of worry, 39% of guilt, 16% of removal difficulty and effort, and 6% of avoidance. Responsibility was a significant contributor to the set for worry (6%), removal difficulty (12%), and guilt (35%). Disapproval was a significant contributor for frequency (4%), worry (3%), removal (4%) effort (12%) and avoidance (5%). Threat. The interaction or threat term accounted for an additional 5% of worry and thought removal scores. The Probability x Responsibility was the only individual significant predictor in both cases. Note that when the threat term was added instead of the two previous sets of its components parts rather than after them, it was a significant contributor to frequency (7%), worry (15%) removal (26%), guilt (32%), effort (12%) and avoidance (5%). This simpler model explained between 5 and 14% less than the more complex model. In other words, the Probability x Cost interaction set alone was not such a strong predictor as the complete set (Probability, Cost, Probability x Cost) despite contributing significantly in all cases except avoidance. So although in general the Probability x Cost interaction was a better predictor than either probability or cost taken individually, the stronger (but less parsimonious model) includes probability, cost, and the interaction term, threat. Discussion The results show that health-related intrusive activity is very common in university students. A full 61% reported having health-related intrusive thoughts in the last month. Further, health-related thoughts were the most frequent intrusions for 21% of the student sample. There were differences between the samples: patients only reported more thoughts than the students, but both patients and escorts named the thought as the most frequent more often than the students. Thus the setting alone would not seem to account for the fact that more patients reported health related thoughts because escorts would also be influenced. However, it may be responsible for them being named as the most frequent: the hospital setting may make health related thoughts more salient among both patients and escorts. As predicted, the presence of triggers was associated with frequency of intrusions as well as worry, removal difficulty, effort in removing the thought and avoidance of
M. H. FREFSTON et al.
210
potential triggers. In fact stimuli were reported as triggering thoughts half the time. This study did not identify whether the triggers were interoceptive (e.g. internal body sensations) or exteroceptive (external triggering events such as conversations, news items, etc.). Further work should identify the nature of such triggers in health anxiety which may also have implications for treatment. The subjective probability of the thought actually occurring (i.e. a current or actual health problem) also contributed substantially to the prediction of all variables except guilt and avoidance, particularly removal difficulty. Probability appraisal is likely to TABLEIV.-HIERARCHICALREGRESSIONANALYSESPREDICTINGFREQUENCY,WORRY, REMOVAL DIFFICULTY,GUILT,EFFORT, AVOIDANCE, FROM APPRAISAL VARIABLES
Set
Sex Triggers Probability Evaluation Responsibility Disapproval Interaction Probability x Resp. Probability x Disap.
Sex Triggers Probability Evaluation Responsibility Disapproval Interaction Probability x Resp. Probability x Disap.
Sex Triggers Probability Evaluation Responsibility Disapproval Interaction Probability x Resp. Probability x Disap.
Sex Triggers Probability Evaluation Responsibility Disapproval Interaction Probability x Resp. Probability x Disap.
F Frequency 0.87 5.53* 16.19** 4.79*
t
B
SR2
2.35 4.02
0.22 0.37
5% 12%
1.88 2.52*
0.17 0.21
3% 4%
0.27 0.33 0.35
7% 10% 11%
2.73*+ 2.12’
0.23 0.17
6% 3%
2.84** 0.95
0.73 0.23
4% 0%
0.20 0.45
4% 18%
4.10** 2.74**
0.34 0.22
12% 4%
3.10** 0.47
0.79 0.11
5% 0%
0.23
4%
0.61 0.20
35% 4%
1.08
Worry 8.69** 14.32 16.43** 7.13**
4.40*
Removal difficulty 0.0 4.32* 25.01** 14.10**
-
4.87**
Guilt 3.87 2.22 5.53* 42.40** 8.22** 2.86 1.91
(Continued).
Health-related
211
thoughts
TABLE IV.-Conrind
Sex
Triggers Probability Evaluation Responsibility Disapproval Interaction Probability x Resp. Probability x Disap.
Sex Triggers Probability Evaluation Responsibility Disapproval Interaction Probability x Resp. Probability x Disap.
Effort 2.82
-
8.90** 1.13 11.37** 1.67 4.28:’
0.28
1%
0.15 0.37
4% 12%
2.12 Avoidance 0.09 5.14* 1.80 3.56 1.16 2.48*
0.21
4%
0.11 0.23
0% 5%
0.71 -
*p < 0.05;**p < 0.01. be directed by both dysfunctional assumptions and factual information or knowledge [20]. The present study suggests that health related intrusive phenomena will be easier to remove, less frequent, and provoke less worry if lower probabilities are assigned to the concern. There is clearly a need for medical personnel to provide accurate information and to correct dysfunctional assumptions in order to reduce the frequency and severity of health related intrusive thoughts. This result is coherent with intervention programs that reduce patient stress and anxiety by informing patients about upcoming medical procedures [38, 391. Note however that the preferred coping style of the individual may determine the ultimate success of this type of intervention [40]. Evaluation of personal responsibility and disapproval were also important predictors of guilt and difficulty removing the thought. Perceived personal responsibility may be based on life style issues such as diet, exercise, sexual practices, and consumption of cigarettes, alcohol, and recreational drugs. It is not surprising that university students in the North American context in 1990 should be aware of their personal responsibility in preventive health care. It is virtually impossible to remain unaware of the media’s treatment of cholesterol, cigarettes, dietary fibre, AIDS, etc. Being aware of such issues and not acting on them in a responsible manner may lead to guilt and anxiety. Disapproval of the thought’s occurrence also accounted for some common variance. It is necessary to further investigate the beliefs of directing thought appraisal [28,41]. These may express beliefs such as ‘thinking about a possible illness can lead to it happening’ similar to the idea that routine examinations ‘might bring sicknes into being, not simply into sight’ ([42] p. 282) that was given by 23% of women in one study as a reason for not going to routine breast screening. The threat term when added later accounted for a smaller but still significant amount of variance in worry and thought removal difficulty scores. That is, high
212
M. H. FREESTONet al.
appraisals of both responsibility and probability were associated with greater worry and difficulty in removing the thought. This suggests the general Threat = Probability x Cost model postulated by Carr [36] for OCD and since tested for other anxiety disorders may also apply for health-anxiety. GENERAL DISCUSSION
These results support other work on intrusive thoughts in general [l 1, 433451: health-related intrusive thoughts do have psychopathological concomitants and appraisal of thoughts is related to their subjective experience. Not surprisingly medical patients reported significantly more health related intrusive thoughts and those thoughts were more often identified as the most frequent intrusion among both patients and escorts than among university students. Although health related thoughts are very prevalent in unselected adult samples, these thoughts would become more frequent, or at least more salient, when triggering events or circumstances are present. Health problems, seeing the doctor, or simply being in a hospital setting would increase salience. The reason for consulting would also play a role: blood tests or X-rays as part of a regular check-up or for other non-threatening reasons would be different from tests due to a serious or unknown condition. Recording the reason for consultation would be enlightening in future studies as would doctor ratings of functional symptoms. The exact nature of the reported thoughts are as yet unknown. Some may be related to the highly specific and time-limited stress related intrusive thoughts studied by Horowitz et al. [lo] and Parkinson and Rachman [13]. Alternatively some thoughts may be perceived as ego-syntonic, probable, and as playing a self-protective role [46], and more closely resemble worrisome thoughts identified in GAD. Finally, some may be more ego-dystonic and senseless in nature and resemble obsessions [44, 471. The treatment implications may be different for each group according to the type of maintaining factors. For example worry-type thoughts may respond to stimulus control [48] whereas more obsessive thoughts would require exposure. The clinical implications of these results are perhaps best considered in the light of the literature on OCD treatment and may apply most to disease phobias, obsessional fears about illness and the ‘subgroup of hypochondriacal patients who are closer to the anxiety disorders in general and to OCD in particular’ ([49] p. 799). Current models of OCD postulate a continuum between normal intrusive thoughts and clinical obsessions [41,50] where appraisal determines both the degree of discomfort, neutralizing activity, and avoidance. Ultimately neutralizing and avoidance lead to repeated thoughts that are evaluated ever more catastrophically and are increasingly difficult to remove. The health-related intrusions in the present study would correspond to one pole of a similar continuum in health-anxiety. In line with the cognitive components of Warwick’s and Salkovskis’ [lS, 191 model of health anxiety, appraisal has been shown to be substantially related to removal difficulty, worry, and guilt associated with intrusions, and to a lesser extent to thought frequency, effort, and avoidance. Providing appropriate corrective information may change appraisals and hence reduce distress, avoidance, and subsequent thoughts. As Warwick and Salkovskis [51,52] have highlighted, the type of information and its presentation are crucial so as not to (a) increase doubt by vague and poorly understood information, (b)
h-related thoughts
213
become part of a cycle of reassurance that brings about short term relief but ultimately reinforces the health anxiety. The second study suggests that both the probability and responsibility dimensions should be addressed. In some cases it may be necessary to downplay the role of lifestyle factors or at least put them in perspective compared to other etiological factors for people who take excessive responsibility. Likewise more general beliefs placing undue weight on the thought’s occurrence should also be corrected by normalizing the experience so the thought itself does not become a cause of concern. We [53] currently use such base rate information on intrusions in the treatment of obsessional thoughts e.g. ‘99% of people report unpleasant thoughts with similar themes, having the thoughts is a normal experience, the degree of discomfort and the use of particular thoughts and behaviors in dealing with the thoughts is what needs attention’. Finally, for more severe cases where the psychological disturbance dominates, exposure to relevant exteroceptive and interoceptive triggers while preventing avoidant anxiety-reducing strategies such as reassurance seeking will allow habituation and provide a powerful source of new information to change appraisal. We have ourselves successfully treated patients with this approach [53] and Logsdail et al. [54] report a series of seven patients with severe AIDS related preoccupations treated by similar methods. Finally, this research highlights the presence of psychopathological symptoms in unselected outpatient samples and further shows that reported health-related intrusions may be a useful marker. Routine questioning about cognitive events related to functional somatic symptoms may help medical personnel better determine which patients have accompanying or predominant health-anxiety [20]. In this case appropriate psychological evaluation may suggest psychological intervention either as an additional strategy, or, in severe cases of health anxiety not related to medical conditions, as the strategy of choice. The appropriate psychometric devices remain to be identified, but rapid assessment instruments similar to those used in the present study are well adapted and easy to use. In conclusion, health-related intrusions are very prevalent among patients and escorts recruited in a hospital setting as well as among university students. These results support cognitive-behavioral models of hypochondriasis and health-anxiety and suggest that strategies being developed for the treatment of other anxiety disorders may be adapted to the specific features of health anxiety. Acknowledgemenrs-This study was supported by a grant from Les Fonds en recherche de Santk du Quebec. The study was completed while the first author was a holder of a studentship from the Medical Research Council of Canada. The authors wish to thank the staff and direction at l’H8pital St-Franqois d’Assise and le Centre Hospitalier de 1’UniversitC Lava1 for the collaboration in allowing and facilitating data collection.
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