The effects of stress and relaxation in the presence of stress on urinary pH and smoking behaviors

0306-4603/ 8 I /040345-09$02.00/ 0 Copyright 0 1981 Pergamon Press Ltd

Addictive Behaviors, Vol. 6, pp. 345-353, 1981 Printed in the USA. All rights reserved.

THE EFFECTS OF STRESS AND RELAXATION IN THE PRESENCE STRESS ON URINARY PH AND SMOKING BEHAVIORS STEVEN

D. DOBBS*,

DANIEL

P. STRICKLER,

University

and WAYNE

OF

A. MAXWELL

of Mississippi

Abstract-The present study examined the influence of stress and relaxation in the presence of stress on smoking behavior and urinary pH. Thirty-two male heavy smokers were randomly assigned to one of three stress groups or a control group. The three stress groups were informed that the last phase of the experiment involved giving a speech to a group of graduate students. They then listened to either a stress enhancing tape, taped relaxation instructions, or a neutral tape. Stress instructions were omitted for the control subjects, and they listened to the neutral tape. Objective (skin conductance response) and subjective (state anxiety) measures of arousal indicated that the treatments had their intended effects. Following treatment subjects were left alone for a 35-minute period during which their smoking behaviors were monitored. The Relaxation Group smoked significantly fewer centimeters of cigarettes (p < .Ol) and at a significantly slower rate (p < .Ol) than the subjects in the two other stress groups. The relationships among stress, urinary pH, relaxation instructions. and smoking behaviors were discussed.

Cigarette smoking has been referred to as a “dependence disorder” (Russell, 197 1) or as an “addiction” (Brecher, 1972) that is maintained by both physiological and psychological variables (Levinson, Shapiro, Schwartz, & Tursky, 1971). In order to understand better various researchers have identified stimulus this addiction or dependence disorder, situations that are discriminative for increases or decreases in cigarette smoking rates and 1974; Russell, 1971; Schachter, Silverstein, amounts (Glad & Adesso, 1976; Herman, Kozlowski, Perlick, Herman, & Liebling, 1977b). Stressful situations, for example, have been found to be associated with significant increases in the number of puffs and the amount of cigarettes smoked relative to nonstress situations (Schachter, Silverstein, Kozlowski, Herman, & Liebling, 1977~; Schachter, Silverstein, & Perlick, 1977d). Conversely, relaxation as the sole treatment (Ravensborg, 1976) or as a component of a broader treatment program (Sutherland, Amit, Golden, & Roseberger, 1975) has been shown to result in a significant short-term reduction in selfreported cigarette smoking. Putting these two findings together, it may be hypothesized that when a person relaxes in the presence of stress, the relaxation serves as an effective coping response which “insulates” the smoker from the stress. This hypothesis seems reasonable in light of evidence that relaxation may mediate the impact of stress on another “dependence disorder,” alcohol drinking behaviors (Strickler, Tomaszewski, Maxwell, & Suib, 1979). Controlled investigations testing this hypothesis, however, are lacking. While previous research has investigated the effects of stress and relaxation separately, no study has been done wherein these two variables are presented simultaneously. The present study, therefore, was designed to determine the effects of relaxation instructions in the presence of stress on various smoking behaviors. Male heavy smokers indicating a fear of public speaking were first matched into quadruplets on the basis of puff rate, amount smoked, and urinary pH measurements taken during pretreatment assessment and assigned to one of four groups. Three stress groups were informed that they would be expected to give a speech (the stress manipulation) and listened to either a relaxation tape (Group S-R), a stress enhancing tape (Group S-S), or a neutral tape (Group S-N). The *Reprint requests may be addressed to Steven D. Dobbs, West Virginia University Medical Center, Behavioral Medicine and Psychiatry, Box 2867-1210 Elmwood Ave., Charleston, West Virginia 25330. Daniel P. Strickler is now at the Department of Psychiatry, Baltimore City Hospitals, Baltimore, MD 21214. Wayne A. Maxwell is now at the Department of Psychology, University of South Dakota, Vermillion, SD 57069.

345

346

STEVEN

D. DOBBS,

DANIEL

P. STRICKLER,

and WAYNE A. MAXWELI

fourth group, the neutral control group (Group N-N), was not threatened with having to give a speech and listened to a neutral tape during treatment. Smoking behaviors were monitored immediately following the treatment phase. Skin conductance response and self-reports of subjective anxiety were measured before and after treatment in order to provide independent verification that the stress manipulation and treatment procedures had their intended physiological and subjective effects. Since Schachter et al. (1977c, 1977d) have shown both that stress may influence changes in urinary pH and that changes in smoking behavior may be associated with changes in urinary pH, urinary pH measurements were obtained three times during the study. It was hypothesized that Groups S-S and S-N would show significant increases in smoking measures during the posttreatment assessment session while Group S-R would show no such increases. METHOD

Subjects Thirty-two male volunteer college students (mean age - 20.6), solicited from undergraduate psychology courses and fraternities on a university campus served as subjects. Prospective subjects were asked to complete a social activities questionnaire that sampled a number of personal preferences including cigarette smoking. Individuals who indicated smoking 20 or more cigarettes (mean number smoked 24.2 cigarettes/day, SD 4.0) with comparable nicotine levels (mean nicotine level - 1.0 mg/cigarette, SD .151), and who also indicated a fear of public speaking on a fear inventory, were selected to participate. q

q

q

Materials and apparatus An Autogen Dermagraph (Model 3400) interfaced with an Autogen Digital Integrator (Model 5400) and an Autogen Dermagraph (Model 3000) interfaced with an Autogen Data Acquisition Center (Model 5400) provided tonic skin conductance response (SCR) data, a sensitive indicant of arousal in stressful situations (Lazarus, Speisman, Nordkoff, & Davidson, 1963). Output represented SCR activity in mhos averaged across one minute intervals. Silver/silver chloride finger electrodes were used (Autogen Systems), with Spectra 260 electrode gel (Parker Laboratories) as the conducting medium. Wollensak and Realistic tape recorders with headphones were used to present the taped instructions. Urinary pH levels were recorded by the Beckman Select-Mate pH/Select-Ion Meter. The State scale of the State-Trait Anxiety Inventory (Spielberger, Gorsuch, & Lushene, 1970) was used to assess subjective anxiety. An interest inventory, consisting of 25 items taken from a pleasant events schedule (MacPhillamy & Lewinson, 1974) that required the subject to rate each activity (e.g., bowling, photography, etc.) on a IO-point preference scale and to indicate those in which they were active participants, was used to provide public speaking topics during the stress phase of the experiment. Setting A total of seven rooms (a lounge, two assessment rooms, two observation rooms, and two treatment rooms) was used. The lounge was the designated subject arrival location. The observation rooms provided the setting from which the raters monitored the smoking behaviors in the two assessment rooms. Each assessment room contained a desk and chairs with an assortment of magazines, a pack of the subject’s preferred brand of cigarettes, an ashtray, matches, and a glass of water in which the subject was asked to extinguish the cigarettes. Both treatment rooms were furnished with a desk, reclining chair, and the biofeedback instruments to monitor SCR. Procedure The subjects were given a brief introduction to the experiment and informed that the study involved an examination of the effects of social factors on personality variables of smokers (cf. Schachter, Kozlowski. & Silverstein, 1977a). They were told that physiologi-

The effects of stress and relaxation

347

cal measures would be taken at various times during the course of the experiment. In addition, the subjects were asked to participate in a parallel study conducted by a fellow graduate student. This study involved an investigation of the effects of persuasive communications in changing audience attitudes and would require them to speak to a small group of people. Upon agreeing to participate, the subjects were instructed not to eat for three hours nor to smoke one hour before their scheduled time of participation. After arrival for the pretreatment assessment, the subjects were informed of the observational procedures used in both sessions and informed consent was obtained. They were then asked to fill out the interest inventory.

Pretreatment assessment The subjects (all participated individually) were first asked to void themselves of urine and drink one pint of water. The subjects were then escorted to an assessment room and informed that they could smoke if they so desired but to extinguish their cigarettes in the glass of water provided. This was done in order to make centimeter measurement of cigarette length smoked easier. The experimenter then left stating that he would return shortly, and the subjects remained undisturbed for 35 minutes. During this interval, puff rate (number of puff/minutes of cigarette duration) was monitored by an observer in the adjacent observation room via a one-way mirror. The amount of cigarettes smoked in centimeters was calculated after the subject left the assessment setting. At the end of the pretreatment session, the STAI-State scale was administered, and urine samples were obtained for pH analysis. Subjects were then rescheduled for the second session on the same day and at the same time the following week. Subjects were matched into quadruplets on the basis of pretreatment puff rate, centimeters smoked, and urinary pH levels. They were then randomly assigned to one of four conditions: (1) speech expectancy and exposed to a stress tape (Group S-S), (2) speech expectancy and presented a relaxation tape (Group S-R), (3) speech expectancy and exposed to a neutral tape (Group S-N), and (4) no speech expectancy and presented a neutral tape (Group N-N). When subjects returned for the second session, all were exposed to the following sequence of events: SCR baseline, stress manipulation, treatment and SCR monitoring, and a posttreatment assessment session. SCR baseline The subjects were again asked to void themselves of urine and drink one pint of water. They were then seated in a reclining chair and finger electrodes were attached. They were asked to remain quiet and to avoid excessive movements. Headphones were placed over the subjects’ ears to block extraneous noise. Skin conductance responses were monitored for the next 20 minutes. Stress manipulation and treatment exposure Following the baseline recording period, the headphones were removed and subjects in the three stressed groups were exposed to the stress manipulation. They were informed that following the experiment,, as part of the collaborative study, they would be speaking to a group of graduate students and faculty in a conference room. Since anticipating having to speak to a group of higher status persons has been shown to be a stress-inducing event (Mulac & Sherman, 1975), the subjects were presented with the following scenario: We have found that our graduate students do not spend enough time in nonacademic activities, which ultimately may have detrimental effects. When it was brought to their attention, we discovered that many were unaware of or uninterested in outside activities. Because of your interest in (whichever activity they had previously rated as being of moderate interest to them), you would be well suited to speak to a group of graduate students and psychology faculty for about 10 minutes during this phase of the experiment. An active participant should be able to convey the enthusiasm necessary to interest and motivate them.

348

STEVEN

D. DOBBS.

DANIEL

P. STRICKLER.

and WAYNE

A. MAXWELL

Our major interest in your talking to the graduate students is determining the effect of persuasive communication on their rated attractiveness and probability of engaging in your activity.

Stress group exposed to stress tape (Group S-S). Subjects in Group S-S were exposed to a stress enhancing tape for 20 minutes. The stress tape was a monologue of a person with “public speaking anxiety” recounting some of his aversive public speaking experiences. A “tense and uneasy” voice told of his discomfort associated with receiving, preparing, and giving a public speaking assignment. Stress group exposed to relaxation tape (Group S-R). The subjects in this condition were given the stress manipulation scenario and then exposed to a 20-minute relaxation tape. A calm voice provided a rationale with instructions for several relaxation techniques intended to relax the body. These included sensory awareness instruction, breathing exercises, and directed relaxation instructions. To avoid interfering with the SCR monitoring, muscle tensing instructions were not included. Stress group exposed to neutral tape (Group S-N). Subjects in Group S-N were given the speech expectancy which was followed by a 20-minute neutral tape which consisted of readings from an introductory psychology textbook on the subject of behavior therapy principles. This group was included in order to control for any effects that may be produced by simply listening to taped material. Neutral group exposed to neutral tape (Group N-N). The threat of having to give a speech was omitted for this group; and the subjects in Group N-N listened to the 20-minute neutral tape. This group was included to provide a no stress, no treatment control. Skin conductance responses were monitored during the tape presentations and STAIState ratings were obtained following exposure to the treatment tapes. Subjects were then asked to wait for approximately 10 minutes after which they gave a urine specimen for pH analysis. Posttreatment assessment The subjects in the speech expectancy conditions (Groups S-S, S-R, and S-N) were seated in an assessment room for 35 minutes. They were given paper and pencil and told to prepare their speech while the experimenter gathered the graduate students and psychology faculty for the “talk.” Subjects in the neutral condition were seated in the assessment room with a variety of magazines and told the experimenter would return in 35 minutes. During this time the smoking behaviors, as in the pretreatment assessment session, were monitored. Subjects in all conditions gave a urine sample for pH analysis and completed another STAI-State scale at the end of the session. It should be noted that the intervals between the urinary measurements were 45 minutes (+2 minutes), and the pint of water the S’s drank prior to each experimental session served to increase the probability of urination but has no appreciable impact on the negative ion concentration. At the completion of the experiment, we answered any questions and discussed the nature of the study with each interested subject. Data collection Twenty-four raters were trained to record puff frequency, cigarette duration, and centimeters smoked, while seven additional raters were trained to use the pH meter to obtain urinary pH levels. Reliability checks were obtained intermittently throughout the study. Mean interrater agreements [(agreements)/(agreements + disagreements)] for these checks were 100% for puff frequency, 95yo for centimeters smoked, 94% for cigarette duration, and 97% for urinary pH readings. Arousal

measures

SCR. Since emotional reactions to the taped material were expected to be evident over time, it seemed appropriate for statistical purposes to use only the middle lo-minute

The effects of stress and relaxation

349

periods of the baseline and treatment sessions. In this way data confounded by the subjects habituating to the physiorecording procedures would not be included and any differential effects of the four stress-treatment manipulations would emerge more clearly. Change scores (difference between mean of middle 10 minutes during baseline and mean of middle 10 minutes during treatment) were computed to assess the psychophysiological responses of the subjects in the four groups. A stress effect was defined as the mean of the middle 10 minutes of treatment being greater than the mean of the middle 10 minutes of baseline, while a relaxation effect was defined as the mean of the middle 10 minutes of treatment being less than the mean of the middle 10 minutes of baseline. Of the eight subjects in Group S-S, 100% showed a stress effect. All eight subjects in Group S-R showed a relaxation. The SCR data of the two control groups were mixed. Two subjects in Group SN (25%) showed a relaxation effect while six (75%) demonstrated a stress effect. Six (75%) of the subjects in Group N-N showed a relaxation effect while the remaining two subjects (25%) showed stress effects. The above SCR change scores for all the groups were analyzed using the Kruskal-Wallis ANOVA by Ranks (Hays, 1973). The results revealed that the taped presentations produced changes in SCR levels (baseline to treatments) that differed significantly (H (3) = 9.06, p < .05). Between group comparisons in the SCR change scores were made using the Mann Whitney U test. The S-S group exhibited significantly larger increases in SCR levels, baseline to treatment, than Group N-N (U 1, p < .002), Group S-R (U = 0, p < .OOl), or Group S-N (U = 13, p < .03). Changes in SCR levels from baseline to treatment for Group S-R were significantly smaller than Group S-N (U = 3,p < .OOl), but did not differ from Group N-N (U = 31, p < .44). Thus in terms of objective arousal measures Group S-S showed significantly greater increases in SCR levels than the other three groups while the S-R participants’ changes in arousal measures baseline to treatment did not differ from those participants who did not receive stress instructions at all (Group N-N). q

STAI-state scale Subjective anxiety measures provided a corollary assessment of the effectiveness of the stress manipulations. Table 1 depicts STAI-State scale mean raw score by group for the pretreatment, treatment, and posttreatment phases. Relative to pretreatment 7 of the 8 (88%) subjects in the S-S group reported increased subjective arousal during the treatment and posttreatment phases of the study. Of the 8 S-R subjects, 5 (63%) had lower scores during the treatment and posttreatment sessions when compared to their pretreatment measures. In the S-N group 4 of the 8 subjects (50%) reported increased subjective arousal relative to pretreatment, while during posttreatment 6 of 8 S-N subjects reported increased arousal when compared to pretreatment. Finally, the changes in STAI-State measures for the N-N group were evenly split for the N-N group with 4 of 8 subjects (500/o) reporting increases (or decreases) during both treatment and posttreatment. These changes scores by group were submitted to a Kruskal Wallis ANOVA by Ranks. The results revealed that the obtained pattern of changes in subjective arousal by group pretreatment to treatment was significant, H (3) 104.3, p < .Ol. Similarly, the pattern of group changes in STAIState scores pretreatment to posttreatment were also significant, H (3) 120.0, p < .Ol. Overall, these analyses demonstrate that the different treatment manipulations had different effects, in the intended directions, on subjective and physiological measures of arousal. q

q

Smoking measures The smoking topography and urinary pH measures were analyzed using a two-way (group by assessment phase) randomized-block factorial ANOVA with repeated measures. The Tukey B test statistic was used for all pair-wise comparisons (Kirk, 1968). Puff rate. Figure phases. The analysis and for assessment

1 depicts the mean puff rate for each group during the assessment revealed a significant main effect for groups, F(3,49) 4.735, p < .Ol, phase, F(1, 49) = 6.243, p < .Ol. The interaction effect was also q

350

STEVEN

D. DOBBS,

DANIEL

P. STRICKLER,

and WAYNE

A. MAXWELL.

Table 1. Mean STAI-state raw scores by assessment phase. Group

Pretreatment

Treatment

s-s S-N S-R N-N

35.5 35.0 31.5 30.6

46.1 36.3 28.0 34.6

Posttreatment 43.5 43.5 32.0 28.1

significant, F(3, 49) = 6.142, p = < .Ol. These results indicate that puff rate differed significantly across phases as a function of treatments and that these changes in puff rate from pre- to posttreatment assessment were related to the treatment conditions. Pre- to post-treatment comparisons revealed a significantly faster posttreatment puff rate for Group S-S, q (1, 49) = 5.02, p < .Ol and Group S-N, q (1, 49) 4.27, p < .Ol. The posttreatment puff rates of Groups N-N and S-R did not differ from pretreatment assessment. During the posttreatment session subjects in Group S-S puffed at a faster rate than subjects in either Group N-N, q (3,49) = 3.63,~ < .05, or Group S-R, q (3,,49) = 6.83, p < .Ol. Group S-N also puffed at a faster rate than subjects in Group S-R during the posttreatment session, q (3, 49) 6.83, p < .Ol. Interestingly, the subjects in Group S-R puffed at a slower rate than the subjects in Group N-N, q (3, 49) = 3.73, p < .05. q

q

Centimeters smoked. The amount of cigarettes smoked in centimeters for each group during the pre- and posttreatment smoking sessions is presented in Figure 2. The ANOVA yielded a significant main effect for groups, F(3, 49) 13.26, p < .Ol, and a significant interaction effect, F(3, 49) 15.25, p < .Ol. The main effect for assessment phase was not significant. These results indicate that the changes in amount smoked pre- to posttreatment differed significantly as a function of the treatment. Post hoc pair-wise comparisons revealed significant posttreatment increases in centimeters smoked for subjects in both Group S-S, q (1,49) = 4.96,~ < .Ol, and Group S-N, q (1, 49) 5.49, p < .01, relative to pretreatment measures. Amount smoked for the subjects in Group N-N did not differ pre- to posttreatment, while the subjects in Group S-R smoked significantly fewer centimeters of cigarettes following treatment than during the pretreatment assessment session, q (1,49) = 4.80,~ < .Ol. During the posttreatment session, Group q

q

q

a s-s

1.8 i

J

I6-

0

S-N

A

n

0.8 Pre Treatment Treatment Fig.

I. Mean pre- and posttreatment

puff rate by group

351

The effects of stress and relaxation

I

1

Post Treatment

Pre Treatment

Fig. 2. Mean pre- and posttreatment

S-R smoked less than 49) 9.93, p < .Ol.

amount

smoked

in centimeters

by group.

S-S, q (3, 49) = 8.66, p < .Ol, and Group

both Group

S-N, q (3,

q

Urinary pH measures Mean urinary pH measures for each assessment interval by treatment condition are presented in Figure 3. Since it was predicted that the stress sensitization subjects would have lower (more acidic) pH measures immediately following the treatment phase, the pH data were analyzed using a planned comparison procedure (Kirk, 1968). The results

0

65

s-s

0 S-N

63-

A

S-R

A

N-N

%i z 6.1-J aI E .p 593 57-

55T, Pre Treatment Treatment Fig. 3. Mean urinary

pH by group

Post Treatment by assessment

phase.

352

STEVEN

D. DOBBS.

DANIEL

P. STRICKLER,

and WAYNE

A. MAXWELL

revealed that Group S-S had significantly lower pH levels following treatment N-N, t (36) = 3.26, p < .Ol, and S-R, t (36) 3.129, p < .Ol. The posttreatment levels did not differ among groups. q

than Groups urinary pH

Interrelationships among dependent measures In order to determine the extent of the relationships among the subjective (STAI) and physiological (SCR) effects of stress, urinary pH, and smoking, several Pearson productmoment correlations were calculated. The change in SCR, baseline to treatment, was significantly correlated with the change in urinary pH, pretreatment to treatment, r (32) = -.46, p < ,005, indicating that increases in SCR were associated with decreases in urinary pH. There was also a significant negative correlation between treatment STAI scores and treatment urinary pH, r (32) = -.33, p < .05. Changes in SCR were significantly related to puff rate, r (32) = .32, p < .04, and amount smoked, r (32) = .42, p < .Ol. Subjects’ treatment pH levels were negatively correlated with amount smoked during the posttreatment assessment session, r (32) -.42, p < .Ol. The correlation between STAI and SCR, smoking rate, and amount smoked failed to reach significance. q

DISCUSSION

The present study was designed to assess the effects of relaxation in the presence of stress on smoking behaviors and urinary pH levels. The SCR measures and STAI data suggest that the treatments had their intended effects on both objective and subjective measures of arousal. Groups S-S and S-N were aroused by the stress manipulation while the relaxation treatment for Group S-R in some way prevented the heightened arousal observed in Groups S-S and S-N, as measured by the STAI and SCR, that was associated with the threat of having to give a speech. That subjects in Groups S-S and S-N smoked more and smoked at a faster rate than during pretreatment assessment is not surprising. This finding is consistent with previous findings concerning the effects of stress on smoking (Schachter et al., 1977~). The important contribution of this study is the finding that Group S-R smoked less and at a slower puff rate during the posttreatment session than the other two stressed groups. Interestingly, puff rate and amount smoked by subjects in Group S-R were lower than those measures for subjects who were not stressed at all. It seems reasonable to conclude that stress is associated with increases in amount and rate of smoking, while relaxation in the presence of stress in some way moderates the impact of stress on smoking behaviors. The effects of stress on smoking can be explained in terms of the interrelationships among the SCR, pH, and smoking measures. Increases in SCR were associated with increases in rate and amount of cigarettes smoked. Since nicotine is a stimulant and several studies have demonstrated that smoking does not calm the smoker (Heimstra, Bancroft, & Dekock, 1967; Perlick, Note 1; Silverstein, Note 2), it has not been clear why subjects increased their intake of nicotine when in the presence of stress. The present data suggest that urinary pH may be the mechanism that mediates the effects of arousal on smoking behavior. Increases in SCR were associated with more acidic pH levels, and the more acidic the pH, the greater the amount smoked in centimeters. Beckett and Triggs (1967) found that the proportion of unmetabolized nicotine that will be excreted in the urine varies with the urine’s acidity. Approximately 3570 of the nicotine will be excreted if the urine is acidic. Thus the increases in smoking behaviors for subjects in Groups S-S and S-N may be viewed as a means of replenishing the nicotine lost via the more rapid rate of urinary excretion associating with stress, suggesting that the smoker adjusts his smoking to keep nicotine at a constant level. This interpretation of the obtained pattern of data is consistent with Schachter’s (1978) theory concerning the pharmacological and psychological determinants of smoking. Interestingly, the relaxation instructions appeared to have countered the effects of stress on both urinary pH and rate of nicotine excretion and eliminated their influence on smoking behaviors. Although the design of the present study attempted to minimize the influence of demand characteristics, it is impossible to determine the extent to which changes in smoking

353

The effects of stress and relaxation

topography were effected by demand variables. The intercorrelation data suggesting a relationship between pH changes and smoking suggest that their influence may have been minimal. In any event, future studies might concentrate on manipulating demand factors as an independent variable to assess their impact on smoking behaviors. The findings of this study may have practical application in the treatment of smoking behaviors, particularly when the treatment goal is controlled smoking (Bernstein, 1969; Frederiksen & Peterson, 1976; Foxx & Brown, 1979). As this study has shown, relaxation may help smokers cope with stressful situations that usually lead to an increase in smoking. Skilled use of relaxation training may simultaneously help the smoker break the chain of behaviors leading to smoking and prevent physiological cravings caused by nicotine loss via the stress influenced lowering of urinary pH levels.

REFERENCE

NOTES

D. The v++thdrawal syndrome: Nicotine addiction and the effects of stopping smoking lighr smokers. Unpublished doctoral dissertation. New York: Columbia University, 1977. 2. Silverstein. B. An addiction explanation of cigarette-induced relaxation. Unpublished doctoral I. Perlick,

New York: Columbia

University,

in heavy1 and

dissertation.

1977.

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