Smoking Cessation in Women Concerned about Weight
Phyllis L. Pinie, PhD, Colleen M. McBride, PhD, Wendy Hellerstedt, MPH, Robert W. Jeffery, PhD, Dorothy Hatsukami PhD, Sharon Allen, MD, and Harny Lando, PhD
Introduction Men and women smokers in the United States are generally similar in their intentions to quit and their quit attempts,12 and they are interested in similar types of cessation programs. I A major exception to this similarity is that women report substantially more concern about weight gain upon quitting2 and are more likely than men to report using smoking as a weight control strategy.3 Although it has been difficult to demonstrate that weight gain is a precipitant of relapse,4 concern about weight gain may act as a barrier to quit attempts. The research reported here is an investigation of treatments that incorporated weight control strategies into a welltested smoking cessation program to create a program that is more acceptable and more attractive to weight-concerned women. The tested weight control strategies were a behavioral weight control program and nicotine polacrilex chewing gum. Nicotine gum, in addition to its demonstrated ability to enhance smoking cessation, has been reported to minimize weight gain among quitters in some studies5-8 though not in others.4,9
Methods Treatment Programs The research design was a randomized factorial trial that tested nicotine gum and a behavioral weight control program alone and in combination; both were added components of the American Lung Association's Freedom from Smoking (FFS) clinic program. Participants were randomized to one of four groups: the FFS program; FFS plus the behavioral weight
control program; FFS plus nicotine gum; or FFS plus both the behavioral weight control program and nicotine gum. The FFS program, selected as one of the best widely available group programs, 10 is an 8-week program, with an orientation meeting plus seven treatment sessions. Meetings emphasize social support and the development of cognitive behavioral skills, such as anticipating and planning for highrisk situations, learning to cope, and preventing relapse. "Quit night" occurs in the fourth week of the program. The behavioral weight control program was designed to help participants avoid weight gain and, should weight gain occur, to maintain a positive attitude about
it. Weight control counseling accompanied each of the seven FFS sessions. Recommendations included decreasing caloric intake by 100 to 300 calories per day (depending on baseline cigarette consumption) and gradually increasing exercise to a goal of 1 hour of walking or its equivalent three times per week. Participants were given calorie counters and food diaries, which they were strongly encouraged to keep throughout the program.
Phyllis L. Pirie, Colleen M. McBride, Wendy Hellerstedt, Robert W. Jeffery, and Harry Lando are with the School of Public Health and Sharon Allen and Dorothy Hatsukami are with the School of Medicine at the University of Minnesota in Minneapolis. Requests for reprints should be sent to Phyllis L. Pirie, PhD, Division of Epidemiology, School of Public Health, University of Minnesota, Minneapolis, MN 55455. This paper was submitted to the Journal August 21, 1991, and accepted with revisions April 7, 1992. Editor's Note. See related editorial by Giovino et al. (p 1203) in this issue.
September 1992, Vol. 82, No. 9
Smoing Cessatdo in Weight-Concerned Women In the groups assigned to receive nicotine chewing gum, the gum (2-mg strength) was supplied free of charge during treatment and for 3 months after treatment ended, and participants were strongly encouraged to use it. Specific training was provided in how best to use the gum, and time was allotted in each group session for discussion about and reinforcement ofits use. No specific amount of gum was prescribed although participants were urged to chew at least three pieces a day. Facilitators were female ex-smokers who had been previously trained by the American Lung Association to be group leaders for the FF5 program. For this research project, additional training was provided regarding the specific additional treatments. Each facilitator was trained to administer all four treatment conditions, and facilitators were crossed by condition. On-site observers in all groups monitored adherence to the specified treatment condition to ensure that material was not introduced inappropriately.
Characteistics and Recnment of Particants Participants were women aged 20 to 64 who wanted to quit smoking and to maintain their weight while quitting; women who expressed a desire to gain weight were excluded. Exclusions for medical reasons (because nicotine gum would be contraindicated) included those who were pregnant or planning a pregnancy; those who were nursing an infant; those with a history of gastric ulcer, substance abuse in the past 6 months, or cardiovascular disease including hypertension; thosewith temporal mandibularjoint syndrome; and those undergoing active cancer treatment. Recruitment and all program activities were conducted primarily in a Minneapolis suburban community. Subjects were recruited from two sources. First, a previous research study involving a population-based screening for cardiovascular risk factors generated a list of 2631 ageeligible women smokers. These women were contacted by telephone for assessment of initial eligibility and were invited to participate. Upon initial screening, 1785 of them were found to be eligible for the study and 264 were eventually randomized into it. Second, because ofinitial concern that the list of smokers from the screening project would not yield a sufficient sample, additional volunteer participants were solicited by word of mouth and by two small newspaper advertise-
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ments. These sources yielded 249 interested women, of whom 153 were eventually randomized. Recruitment overall was more successful than had been projected, and the goal ofrecruiting and randomizing 360 individuals was surpassed by 57 individuals, for a total of417 randomized subjects. To facilitate the continuous recruitment and enrollment of subjects without delay in the beginning of treatment, treatment was administered in four consecutive cycles, with each treatment condition represented within each cycle. Thus, there was a total of 16 treatment groups.
Data Collection Procedures Interested women were invited to attend a baseline clinic, which included the completion of demographic questionnaires, smoking history, and weight history; weight measurement with a balance beam scale; the assessment of possible contraindications to nicotine gum; and the collection of biochemical measures of smoking status (i.e., expired air for measuring carbon monoxide and saliva for measuring thiocyanate and cotinine). Participants at the baseline clinic were given a detailed explanation of the study and asked to sign a consent form indicating their acceptance of study procedures. Those signing the consent form were then randomly assigned to a weeknight and site for class participation. At the orientation meeting, the treatment assignment was announced to the group. All participants who attended this orientation meeting were considered participants in the full study. Compliance with treatment recommendations was assessed by session attendance, by self-report items regarding completion of smoking-related "assignments" (e.g., smoking records, reading materials, self-assessment exercises, etc.), and by self-report items in the appropriate groups regarding completion of food records and use of nicotine gum. Weight was measured with a balance beam scale at each group session. Expired air carbon monoxide was measured 1 week after the quit date and at the end of treatment (4 weeks after the quit date). Salivawas collected for biochemical (both thiocyanate and cotinine) validation at the end of treatment and was analyzed in the laboratory only for those individuals reporting themselves to be abstinent. Follow-up data collection was conducted in a clinic, with assessments similar to those conducted at baseline at 6 and 12 months after the end of treatment. A
detailed questionnaire asked about current smoking status and smoking since the last contact, relapse situations, and withdrawal symptoms. As was done at the end of treatment, saliva was analyzed only for those individuals reporting themselves to be abstinent.
Monetary Contingencies Participants were asked to make a $100 deposit at the time of the baseline clinic; this deposit was to be completely refunded upon completion of the 12month follow-up clinic, regardless of smoking status at that time. A small number ofparticipants who could not pay $100 paid smaller amounts but never less than
$40.
Definitions Two definitions of abstinence were used in this study: continuous abstinence (no smoking at all since the program quit night) and point prevalence abstinence (no smoking in the past 7 days). Self-reported abstinence was verified by an expired air carbon monoxide reading of less than or equal to 10 ppm; if the value was higher than 10 in a self-reported nonsmoker, we accepted a cotinine value of less than or equal to 10 ng/mL (in the groups not receiving nicotine gum) or a thiocyanate value of less than 100 p,mol/L (in the groups receiving nicotine gum) as evidence of nonsmoking. According to these criteria, only one individual was believed to be misreporting smoking status at follow-up, and that person was treated as a smoker in the analyses.
Analysis Methods Differences between treatment groups were examined at baseline, at the end of treatment (session 7 of the FFS program), and at 6 and 12 months posttreatment using X2 analysis for categorical variables and general linear model procdures for continuous variables. The SAS package of statis-
tical programs was used.11 Preliminary analyses revealed no design effects for smoking-that is, no differences within treatments within cycles that could be considered specific to individual cycles. Hence, the analysis of treatment conditions was based on all randomized individuals without accounting for the cycle in which they
participatedAmerican Journal of Public Health 1239
Phie et aL
Results
Baseline Comparisons Table 1 shows selected baseline characteristics of participants randomized to each ofthe four treatment conditions. Participants in the four treatment conditions were statistically equivalent at baseline on all variables relevant to the treatment. Reported baseline smoking levels ranged from 4 to 105 cigarettes per day, with an average of 26.2 cigarettes. Although participants were concerned about weight, most did not appear to be obese; at baseline, they averaged 107% of the median recommended weight for height according to the recent (1983) life insurance industry tables.12
Prcess Measures No incidents were recorded in which group leaders deviated from the assigned protocol for a given treatment group. Table 2 summarizes compliance data by treatment group. Meeting attendance was quite good, averaging 7.3 of 8 meetings. Self-reported compliance with treatment recommendations was more variable. Compliance with the smoking-related assignments differed across treatment groups in some sessions, with the best average for compliance reported in the group receiving both the behavioral weight control treatment and nicotine gum.
1240 American Journal of Public Health
FoUlow-up Success Data were collected in the follow-up clinics on 98.3% of participants at 6 months and on 98.1% of participants at 12 months. Those few participants who had moved out of the area were allowed to complete self-report assessments by telephone and mail, resulting in 100% participation in the follow-up assessments.
Weight Change Outcomes Because weight gain was expected to be markedly different in smokers and nonsmokers and because length of abstinence was expected to be related to the amount of weight gained, weight change was analyzed at each follow-up point for the subgroup who remained continuously abstinent for the entire 12 months of follow-up (n = 88) and the subgroup who reported smolng continuously throughout the 12 months of follow-up (i.e., those who were smoking at each follow-up point) (n = 176). As expected, weight gain was pronounced in continuous abstainers, averaging 10.6 lb by the 12-month follow-up; itwasvery slight in the continuous smokers (1.6 lb by 12 months) (Table 3). Most of the weight gined was pined by the 6-month follow-up. Among those who were continuously abstinent, 70.5% gained at least 5 lb by the 12-month
follow-up. Although our treatment hypothesis was that abstinent individuals in groups receiving the behavioral weight control treat-
ment or nicotine gum would demonstrate lower weight gains than individuals receiving the standard treatment, thatwas not the case (Table 4). Among the yearlong continuous abstainers, no significant differences in weight gain are seen between any of the treatment conditions at any follow-up point. During treatment, it appears that successful quitters in the treatment conditions that included the behavioral weight control treatment began to lose weight until quit night (session 3), after which their weights returned to and exceeded baseline levels (data not shown). Among those abstinent at the end of treatment, weight gain was not found to be significantly different for those who were chewing gum versus those who were not, nor did it vary according to the amount of gum chewed. Similarly, at 6-month follow-up, weight gain was not found to be significantly different for those who were chewing gum versus those who were not.
Smoking Outcomes Significant differences in abstinence among the treatment conditions are seen at each follow-up point (Table 5). The group receiving nicotine gum demonstrated the highest point prevalence and continuous abstinence rates at each follow-up point, whereas the group receiving just the basic smoking cessation program demonstrated the lowest smoking cessation rate at each follow-up point.
September 1992, Vol. 82, No. 9
Sming Cessation in Weight-Conerned Women
Given that we were unable to produce significant differences in weight gain across the treatment conditions, we are unable to analyze the effects of weight gain on smoking status at the group level. At the individual level, we found that, among successful quitters who had gained more than 5 lb by the end of treatment, the proportion who relapsed to smoking by the 6-month follow-up was 51.2% (95% CI = 36.3%, 66.1%), as compared with 39.9% (95% CI = 32.9%, 46.9%) in quitters who had gained 5 lb or less. Of those who were not smoking at the 6-month follow-up and who had gained more than 5 lb, the proportion who relapsed to smoking by the 12-month follow-up was 19.4% (95% CI = 11.8%,27.0%).This compares with 13.2% (95% CI = 2.4%, 24.0%) relapsing among those who had gained less than 5 lb.
Disusion Self-reports from smokers, which suggest that weight gain is a common
September 1992, Vol. 82, No. 9
cause of relapse to cigarette smoking, lead to the exectation that the individuals who gained more weight following smoking
cessation would demonstrate higher levels of relapse. Our ability to test this hypothesis was compromised, however, by our lack of success in producing differential weight changes among the treatment groups in this study. This outcome was unexpected, given that behavioral treatments of the type used here have been used successfiullyin manyweight loss programs, and nicotine gum has often been shown to reduce weight gain in quitters
who chew it. Compliance data may supply part of the explanation. Although excellent compliance was recorded for meeting attendance and use of nicotine gum, selfreported compliance with other treatment recommendations (e.g., completion of smoking-related assignments and of food records) was not as good. Compliance with the behavioral weight control intervention apparently declined following quit night, indicating perhaps that complying with two behavioral interventions simultaneously was difficult for participants. At the individual level, women who American Journal of Public Health 1241
Phie et aL
gained more weight were not significantly more likely to relapse to smoking than women who gained less weight. At least one study4 has found that those who gained more weight by the 6-month follow-up were more (rather than less) likely to be abstinent at 12 months. The results of the two studies may be partly related to the stage at which weight gain is assessed. It maybe that extremelyweight conscious individuals tend to respond to small increments in weight by relapsing in the early period. Among those who have managed to remain abstinent by 6 months, however, weight may be less of an issue. Hence, weight gain may be unrelated to further relapse, as in our study, or it may even be a marker for those who are strongly motivated enough to continue abstinence, as in the Hall et al. study.4 It is also surprising that we did not observe differential weight gain in those chewing and not chewing nicotine gum. Although many studies report the weight control effects of nicotine gum, it is not clear from the literature how much gum is 1242
American Journal of Public Health
needed to produce such effects, nor how long the gum must be used to produce this result. We saw no enhanced weight controL not even in those chewing 10 pieces a day at the end of treatment or in those continuing to use gum at 6 months as compared with those not using it. As expected, this study demonstrated that adding nicotine gum to a group-based program can produce outstanding validated cessation results at the 12-month follow-up. This has also been demonstrated in other studies.13 However, the treatment group receiving both nicotine gum and the behavioral weight control program as adjuncts to the FFS program produced smoking cessation rates that were significantly lower by the 12-month follow-up than those for the group receiving just nicotine gum as an adjunct to the basic program. The hypothesis that the combination of several treatments resulted in "overload" on the part of the participants is attractive but unproven. For example, there is no evidence that individuals in the group receiving the
combined intervention demonstrated poorer compliance with treatment recommendations than those in the nicotine gum group; in fact, the group receiving the combined intervention generally had the highest compliance rates. It is clear, though, that even the combined treatments did not detract from the smoking cessation outcome of the program. On average, those receiving the weight control treatments did as well as or better than those receiving the standard FES program, and all the treatment conditions did about as well as or better than comparable group treatments reported elsewhere.14 Thus, it is clearly not the case that adding weight control components will reduce the smoldng cessation that can be achieved by a high-quality group pro-
gramn
An unexpected observation made in the course of implementing this program was the attractiveness of the program to potential participants; the program roster was easily filled and even overfilled by the final enrollment cycle. In our previous ex-
September 1992, Vol. 82, No. 9
Smokng Cessaion n Weight-CAnceried Women
periences with Minnesota communities, recruitment had been much more difficult. For example, Schmid et al.15 had recruited about 1.4% of smokers in two communities to home correspondence courses, and Lando et al.16 report that several communitywide smoking cessation contests had attracted 3% to 5% of smokers in each community. In contrast, this project, with careful eligibility screening and a required monetaly deposit, succeeded in randomizing 14.8% of an identified population of smokers. It appears that smokers perceive a need for programs that will address their legitimate concerns about gaining weight when they quit smoking. It is possible that some of the participants in this program may not have been willing to participate in other, more traditional smoking cessation treatments. For this reason iffor no other, continued investigation of combined weight control and smoking cessation treatments is warranted. 0
forts of Ms. Karen Viniig, who organized and supervised the initial telephone contacts and much of the follow-up data collection, and Ms. Gail Dolliff, who organized and supervised the baseline and follow-up clinics.
57:87-92. 9. Tonnesen P, Fryd V, Hansen M, et al. Two- and four-mg nicotine chewing gum and group counseling in smoking cessation: an open, randomized, controlled trial with a 22-month follow-up.AddictBehav. 1988; 13:17-27. 10. Lando HA, McGovern PG, Barrios F, Etringer BD. Comparative evaluation of American Cancer Society and American Lung Association smoldng cessation clinics. Am J Pubic Healk 1990;80:554-559. 11. SAS Institute Inc. &4S User's Guide. Version 5. Cary, NC: SAS Institute Inc.; 1985: 956. 12. 1983 Metropolitan height and weight tables. Stat Bull Metrop Insur Co. 1984;64: 2-9. 13. Lam W, Sacks HS, Sze PC, Chalmers TC. Meta-anabsis of randomized controlled trials of nicotine chewing gum. Lancet. 1987; ii:27-30. 14. Schwartz JL. Review and Evaluton of Smodg Cessation Medhds: 7he United States and Canada, 1978-1985. Washington, DC: Division of Cancer Prevention and Control, National Cancer Institute; 1987:200. NIH publication 87-2940. 15. Schmid TL, Jeffery RW, Helierstedt W. Direct mail recruitment to home-based smoking and weight control prrams: a comparison of strategies. Prev Med. 1989; 18:503-517. 16. Lando HA, Loken B, Howard-Pitney B, Pechacek T. Community impact of a localized smoking cessation contest.AmJJPublic Healh. 1990;80:601-603.
References 1. Lando HA, Pirie PL, Hellerstedt WL, McGovern PG. Survey of smoking patterns, attitudes, and interest in quitting.Am
JPrnvMedL 1991;7:18-23. 2. Pirie PL, Murray DM, Luepker RB. Gender differences in cigarette smoking and quitting in a cohort of young adults. Am J Public Health. 1991;81:324-327. 3. Klesges RC, Klesges LM. Cigarette smoking as a dieting strategy in a university population. Int J EaiVg DisonL 1988;7:413419. 4. Hall SM, Ginsberg D, Jones RT. Smoking cessation and weight gain. J Consult Clin PsychoL 1986;54:342-346. 5. Fagerstrom KO. Reducing the weight gain after stopping smoking. Addict Behav. 1987;12:91-93. 6. Emont SL, Cummings KM. Weight gain following smoking cessation: a possible role for nicotine replacement in weight management. Addict Behav. 1987;12:151155. 7. HajekP, Jackson P, Belcher M. Long-term use ofnicotine chewing gum.JAMA. 1988;
Acknowledgments This research was supported by grant no. CA41647 from the National Cancer Institute; Phyllis L. Pide was principal investigator. The assistance of Ms. Penny Gottier of the American Lung Association, Hennepin County affiliate, is gratefully acknowledged. The authors also wish to acknowledge the ef-
260:1593-15%. 8. Gross J, Stitzer ML, Maldonado J. Nicotine replacement: effects on postcessation weight gain. J Consult Clin PsychoL 1989;
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American Journal of Public Health 1243
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Phyllis L. Pinie, PhD, Colleen M. McBride, PhD, Wendy Hellerstedt, MPH, Robert W. Jeffery, PhD, Dorothy Hatsukami PhD, Sharon Allen, MD, and Harny Lando, PhD
Introduction Men and women smokers in the United States are generally similar in their intentions to quit and their quit attempts,12 and they are interested in similar types of cessation programs. I A major exception to this similarity is that women report substantially more concern about weight gain upon quitting2 and are more likely than men to report using smoking as a weight control strategy.3 Although it has been difficult to demonstrate that weight gain is a precipitant of relapse,4 concern about weight gain may act as a barrier to quit attempts. The research reported here is an investigation of treatments that incorporated weight control strategies into a welltested smoking cessation program to create a program that is more acceptable and more attractive to weight-concerned women. The tested weight control strategies were a behavioral weight control program and nicotine polacrilex chewing gum. Nicotine gum, in addition to its demonstrated ability to enhance smoking cessation, has been reported to minimize weight gain among quitters in some studies5-8 though not in others.4,9
Methods Treatment Programs The research design was a randomized factorial trial that tested nicotine gum and a behavioral weight control program alone and in combination; both were added components of the American Lung Association's Freedom from Smoking (FFS) clinic program. Participants were randomized to one of four groups: the FFS program; FFS plus the behavioral weight
control program; FFS plus nicotine gum; or FFS plus both the behavioral weight control program and nicotine gum. The FFS program, selected as one of the best widely available group programs, 10 is an 8-week program, with an orientation meeting plus seven treatment sessions. Meetings emphasize social support and the development of cognitive behavioral skills, such as anticipating and planning for highrisk situations, learning to cope, and preventing relapse. "Quit night" occurs in the fourth week of the program. The behavioral weight control program was designed to help participants avoid weight gain and, should weight gain occur, to maintain a positive attitude about
it. Weight control counseling accompanied each of the seven FFS sessions. Recommendations included decreasing caloric intake by 100 to 300 calories per day (depending on baseline cigarette consumption) and gradually increasing exercise to a goal of 1 hour of walking or its equivalent three times per week. Participants were given calorie counters and food diaries, which they were strongly encouraged to keep throughout the program.
Phyllis L. Pirie, Colleen M. McBride, Wendy Hellerstedt, Robert W. Jeffery, and Harry Lando are with the School of Public Health and Sharon Allen and Dorothy Hatsukami are with the School of Medicine at the University of Minnesota in Minneapolis. Requests for reprints should be sent to Phyllis L. Pirie, PhD, Division of Epidemiology, School of Public Health, University of Minnesota, Minneapolis, MN 55455. This paper was submitted to the Journal August 21, 1991, and accepted with revisions April 7, 1992. Editor's Note. See related editorial by Giovino et al. (p 1203) in this issue.
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Smoing Cessatdo in Weight-Concerned Women In the groups assigned to receive nicotine chewing gum, the gum (2-mg strength) was supplied free of charge during treatment and for 3 months after treatment ended, and participants were strongly encouraged to use it. Specific training was provided in how best to use the gum, and time was allotted in each group session for discussion about and reinforcement ofits use. No specific amount of gum was prescribed although participants were urged to chew at least three pieces a day. Facilitators were female ex-smokers who had been previously trained by the American Lung Association to be group leaders for the FF5 program. For this research project, additional training was provided regarding the specific additional treatments. Each facilitator was trained to administer all four treatment conditions, and facilitators were crossed by condition. On-site observers in all groups monitored adherence to the specified treatment condition to ensure that material was not introduced inappropriately.
Characteistics and Recnment of Particants Participants were women aged 20 to 64 who wanted to quit smoking and to maintain their weight while quitting; women who expressed a desire to gain weight were excluded. Exclusions for medical reasons (because nicotine gum would be contraindicated) included those who were pregnant or planning a pregnancy; those who were nursing an infant; those with a history of gastric ulcer, substance abuse in the past 6 months, or cardiovascular disease including hypertension; thosewith temporal mandibularjoint syndrome; and those undergoing active cancer treatment. Recruitment and all program activities were conducted primarily in a Minneapolis suburban community. Subjects were recruited from two sources. First, a previous research study involving a population-based screening for cardiovascular risk factors generated a list of 2631 ageeligible women smokers. These women were contacted by telephone for assessment of initial eligibility and were invited to participate. Upon initial screening, 1785 of them were found to be eligible for the study and 264 were eventually randomized into it. Second, because ofinitial concern that the list of smokers from the screening project would not yield a sufficient sample, additional volunteer participants were solicited by word of mouth and by two small newspaper advertise-
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ments. These sources yielded 249 interested women, of whom 153 were eventually randomized. Recruitment overall was more successful than had been projected, and the goal ofrecruiting and randomizing 360 individuals was surpassed by 57 individuals, for a total of417 randomized subjects. To facilitate the continuous recruitment and enrollment of subjects without delay in the beginning of treatment, treatment was administered in four consecutive cycles, with each treatment condition represented within each cycle. Thus, there was a total of 16 treatment groups.
Data Collection Procedures Interested women were invited to attend a baseline clinic, which included the completion of demographic questionnaires, smoking history, and weight history; weight measurement with a balance beam scale; the assessment of possible contraindications to nicotine gum; and the collection of biochemical measures of smoking status (i.e., expired air for measuring carbon monoxide and saliva for measuring thiocyanate and cotinine). Participants at the baseline clinic were given a detailed explanation of the study and asked to sign a consent form indicating their acceptance of study procedures. Those signing the consent form were then randomly assigned to a weeknight and site for class participation. At the orientation meeting, the treatment assignment was announced to the group. All participants who attended this orientation meeting were considered participants in the full study. Compliance with treatment recommendations was assessed by session attendance, by self-report items regarding completion of smoking-related "assignments" (e.g., smoking records, reading materials, self-assessment exercises, etc.), and by self-report items in the appropriate groups regarding completion of food records and use of nicotine gum. Weight was measured with a balance beam scale at each group session. Expired air carbon monoxide was measured 1 week after the quit date and at the end of treatment (4 weeks after the quit date). Salivawas collected for biochemical (both thiocyanate and cotinine) validation at the end of treatment and was analyzed in the laboratory only for those individuals reporting themselves to be abstinent. Follow-up data collection was conducted in a clinic, with assessments similar to those conducted at baseline at 6 and 12 months after the end of treatment. A
detailed questionnaire asked about current smoking status and smoking since the last contact, relapse situations, and withdrawal symptoms. As was done at the end of treatment, saliva was analyzed only for those individuals reporting themselves to be abstinent.
Monetary Contingencies Participants were asked to make a $100 deposit at the time of the baseline clinic; this deposit was to be completely refunded upon completion of the 12month follow-up clinic, regardless of smoking status at that time. A small number ofparticipants who could not pay $100 paid smaller amounts but never less than
$40.
Definitions Two definitions of abstinence were used in this study: continuous abstinence (no smoking at all since the program quit night) and point prevalence abstinence (no smoking in the past 7 days). Self-reported abstinence was verified by an expired air carbon monoxide reading of less than or equal to 10 ppm; if the value was higher than 10 in a self-reported nonsmoker, we accepted a cotinine value of less than or equal to 10 ng/mL (in the groups not receiving nicotine gum) or a thiocyanate value of less than 100 p,mol/L (in the groups receiving nicotine gum) as evidence of nonsmoking. According to these criteria, only one individual was believed to be misreporting smoking status at follow-up, and that person was treated as a smoker in the analyses.
Analysis Methods Differences between treatment groups were examined at baseline, at the end of treatment (session 7 of the FFS program), and at 6 and 12 months posttreatment using X2 analysis for categorical variables and general linear model procdures for continuous variables. The SAS package of statis-
tical programs was used.11 Preliminary analyses revealed no design effects for smoking-that is, no differences within treatments within cycles that could be considered specific to individual cycles. Hence, the analysis of treatment conditions was based on all randomized individuals without accounting for the cycle in which they
participatedAmerican Journal of Public Health 1239
Phie et aL
Results
Baseline Comparisons Table 1 shows selected baseline characteristics of participants randomized to each ofthe four treatment conditions. Participants in the four treatment conditions were statistically equivalent at baseline on all variables relevant to the treatment. Reported baseline smoking levels ranged from 4 to 105 cigarettes per day, with an average of 26.2 cigarettes. Although participants were concerned about weight, most did not appear to be obese; at baseline, they averaged 107% of the median recommended weight for height according to the recent (1983) life insurance industry tables.12
Prcess Measures No incidents were recorded in which group leaders deviated from the assigned protocol for a given treatment group. Table 2 summarizes compliance data by treatment group. Meeting attendance was quite good, averaging 7.3 of 8 meetings. Self-reported compliance with treatment recommendations was more variable. Compliance with the smoking-related assignments differed across treatment groups in some sessions, with the best average for compliance reported in the group receiving both the behavioral weight control treatment and nicotine gum.
1240 American Journal of Public Health
FoUlow-up Success Data were collected in the follow-up clinics on 98.3% of participants at 6 months and on 98.1% of participants at 12 months. Those few participants who had moved out of the area were allowed to complete self-report assessments by telephone and mail, resulting in 100% participation in the follow-up assessments.
Weight Change Outcomes Because weight gain was expected to be markedly different in smokers and nonsmokers and because length of abstinence was expected to be related to the amount of weight gained, weight change was analyzed at each follow-up point for the subgroup who remained continuously abstinent for the entire 12 months of follow-up (n = 88) and the subgroup who reported smolng continuously throughout the 12 months of follow-up (i.e., those who were smoking at each follow-up point) (n = 176). As expected, weight gain was pronounced in continuous abstainers, averaging 10.6 lb by the 12-month follow-up; itwasvery slight in the continuous smokers (1.6 lb by 12 months) (Table 3). Most of the weight gined was pined by the 6-month follow-up. Among those who were continuously abstinent, 70.5% gained at least 5 lb by the 12-month
follow-up. Although our treatment hypothesis was that abstinent individuals in groups receiving the behavioral weight control treat-
ment or nicotine gum would demonstrate lower weight gains than individuals receiving the standard treatment, thatwas not the case (Table 4). Among the yearlong continuous abstainers, no significant differences in weight gain are seen between any of the treatment conditions at any follow-up point. During treatment, it appears that successful quitters in the treatment conditions that included the behavioral weight control treatment began to lose weight until quit night (session 3), after which their weights returned to and exceeded baseline levels (data not shown). Among those abstinent at the end of treatment, weight gain was not found to be significantly different for those who were chewing gum versus those who were not, nor did it vary according to the amount of gum chewed. Similarly, at 6-month follow-up, weight gain was not found to be significantly different for those who were chewing gum versus those who were not.
Smoking Outcomes Significant differences in abstinence among the treatment conditions are seen at each follow-up point (Table 5). The group receiving nicotine gum demonstrated the highest point prevalence and continuous abstinence rates at each follow-up point, whereas the group receiving just the basic smoking cessation program demonstrated the lowest smoking cessation rate at each follow-up point.
September 1992, Vol. 82, No. 9
Sming Cessation in Weight-Conerned Women
Given that we were unable to produce significant differences in weight gain across the treatment conditions, we are unable to analyze the effects of weight gain on smoking status at the group level. At the individual level, we found that, among successful quitters who had gained more than 5 lb by the end of treatment, the proportion who relapsed to smoking by the 6-month follow-up was 51.2% (95% CI = 36.3%, 66.1%), as compared with 39.9% (95% CI = 32.9%, 46.9%) in quitters who had gained 5 lb or less. Of those who were not smoking at the 6-month follow-up and who had gained more than 5 lb, the proportion who relapsed to smoking by the 12-month follow-up was 19.4% (95% CI = 11.8%,27.0%).This compares with 13.2% (95% CI = 2.4%, 24.0%) relapsing among those who had gained less than 5 lb.
Disusion Self-reports from smokers, which suggest that weight gain is a common
September 1992, Vol. 82, No. 9
cause of relapse to cigarette smoking, lead to the exectation that the individuals who gained more weight following smoking
cessation would demonstrate higher levels of relapse. Our ability to test this hypothesis was compromised, however, by our lack of success in producing differential weight changes among the treatment groups in this study. This outcome was unexpected, given that behavioral treatments of the type used here have been used successfiullyin manyweight loss programs, and nicotine gum has often been shown to reduce weight gain in quitters
who chew it. Compliance data may supply part of the explanation. Although excellent compliance was recorded for meeting attendance and use of nicotine gum, selfreported compliance with other treatment recommendations (e.g., completion of smoking-related assignments and of food records) was not as good. Compliance with the behavioral weight control intervention apparently declined following quit night, indicating perhaps that complying with two behavioral interventions simultaneously was difficult for participants. At the individual level, women who American Journal of Public Health 1241
Phie et aL
gained more weight were not significantly more likely to relapse to smoking than women who gained less weight. At least one study4 has found that those who gained more weight by the 6-month follow-up were more (rather than less) likely to be abstinent at 12 months. The results of the two studies may be partly related to the stage at which weight gain is assessed. It maybe that extremelyweight conscious individuals tend to respond to small increments in weight by relapsing in the early period. Among those who have managed to remain abstinent by 6 months, however, weight may be less of an issue. Hence, weight gain may be unrelated to further relapse, as in our study, or it may even be a marker for those who are strongly motivated enough to continue abstinence, as in the Hall et al. study.4 It is also surprising that we did not observe differential weight gain in those chewing and not chewing nicotine gum. Although many studies report the weight control effects of nicotine gum, it is not clear from the literature how much gum is 1242
American Journal of Public Health
needed to produce such effects, nor how long the gum must be used to produce this result. We saw no enhanced weight controL not even in those chewing 10 pieces a day at the end of treatment or in those continuing to use gum at 6 months as compared with those not using it. As expected, this study demonstrated that adding nicotine gum to a group-based program can produce outstanding validated cessation results at the 12-month follow-up. This has also been demonstrated in other studies.13 However, the treatment group receiving both nicotine gum and the behavioral weight control program as adjuncts to the FFS program produced smoking cessation rates that were significantly lower by the 12-month follow-up than those for the group receiving just nicotine gum as an adjunct to the basic program. The hypothesis that the combination of several treatments resulted in "overload" on the part of the participants is attractive but unproven. For example, there is no evidence that individuals in the group receiving the
combined intervention demonstrated poorer compliance with treatment recommendations than those in the nicotine gum group; in fact, the group receiving the combined intervention generally had the highest compliance rates. It is clear, though, that even the combined treatments did not detract from the smoking cessation outcome of the program. On average, those receiving the weight control treatments did as well as or better than those receiving the standard FES program, and all the treatment conditions did about as well as or better than comparable group treatments reported elsewhere.14 Thus, it is clearly not the case that adding weight control components will reduce the smoldng cessation that can be achieved by a high-quality group pro-
gramn
An unexpected observation made in the course of implementing this program was the attractiveness of the program to potential participants; the program roster was easily filled and even overfilled by the final enrollment cycle. In our previous ex-
September 1992, Vol. 82, No. 9
Smokng Cessaion n Weight-CAnceried Women
periences with Minnesota communities, recruitment had been much more difficult. For example, Schmid et al.15 had recruited about 1.4% of smokers in two communities to home correspondence courses, and Lando et al.16 report that several communitywide smoking cessation contests had attracted 3% to 5% of smokers in each community. In contrast, this project, with careful eligibility screening and a required monetaly deposit, succeeded in randomizing 14.8% of an identified population of smokers. It appears that smokers perceive a need for programs that will address their legitimate concerns about gaining weight when they quit smoking. It is possible that some of the participants in this program may not have been willing to participate in other, more traditional smoking cessation treatments. For this reason iffor no other, continued investigation of combined weight control and smoking cessation treatments is warranted. 0
forts of Ms. Karen Viniig, who organized and supervised the initial telephone contacts and much of the follow-up data collection, and Ms. Gail Dolliff, who organized and supervised the baseline and follow-up clinics.
57:87-92. 9. Tonnesen P, Fryd V, Hansen M, et al. Two- and four-mg nicotine chewing gum and group counseling in smoking cessation: an open, randomized, controlled trial with a 22-month follow-up.AddictBehav. 1988; 13:17-27. 10. Lando HA, McGovern PG, Barrios F, Etringer BD. Comparative evaluation of American Cancer Society and American Lung Association smoldng cessation clinics. Am J Pubic Healk 1990;80:554-559. 11. SAS Institute Inc. &4S User's Guide. Version 5. Cary, NC: SAS Institute Inc.; 1985: 956. 12. 1983 Metropolitan height and weight tables. Stat Bull Metrop Insur Co. 1984;64: 2-9. 13. Lam W, Sacks HS, Sze PC, Chalmers TC. Meta-anabsis of randomized controlled trials of nicotine chewing gum. Lancet. 1987; ii:27-30. 14. Schwartz JL. Review and Evaluton of Smodg Cessation Medhds: 7he United States and Canada, 1978-1985. Washington, DC: Division of Cancer Prevention and Control, National Cancer Institute; 1987:200. NIH publication 87-2940. 15. Schmid TL, Jeffery RW, Helierstedt W. Direct mail recruitment to home-based smoking and weight control prrams: a comparison of strategies. Prev Med. 1989; 18:503-517. 16. Lando HA, Loken B, Howard-Pitney B, Pechacek T. Community impact of a localized smoking cessation contest.AmJJPublic Healh. 1990;80:601-603.
References 1. Lando HA, Pirie PL, Hellerstedt WL, McGovern PG. Survey of smoking patterns, attitudes, and interest in quitting.Am
JPrnvMedL 1991;7:18-23. 2. Pirie PL, Murray DM, Luepker RB. Gender differences in cigarette smoking and quitting in a cohort of young adults. Am J Public Health. 1991;81:324-327. 3. Klesges RC, Klesges LM. Cigarette smoking as a dieting strategy in a university population. Int J EaiVg DisonL 1988;7:413419. 4. Hall SM, Ginsberg D, Jones RT. Smoking cessation and weight gain. J Consult Clin PsychoL 1986;54:342-346. 5. Fagerstrom KO. Reducing the weight gain after stopping smoking. Addict Behav. 1987;12:91-93. 6. Emont SL, Cummings KM. Weight gain following smoking cessation: a possible role for nicotine replacement in weight management. Addict Behav. 1987;12:151155. 7. HajekP, Jackson P, Belcher M. Long-term use ofnicotine chewing gum.JAMA. 1988;
Acknowledgments This research was supported by grant no. CA41647 from the National Cancer Institute; Phyllis L. Pide was principal investigator. The assistance of Ms. Penny Gottier of the American Lung Association, Hennepin County affiliate, is gratefully acknowledged. The authors also wish to acknowledge the ef-
260:1593-15%. 8. Gross J, Stitzer ML, Maldonado J. Nicotine replacement: effects on postcessation weight gain. J Consult Clin PsychoL 1989;
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