HEALTH PSYCHOLOGY, 1992,11(5), 331-334 Copyright © 1992, Lawrence Erlbaum Associates, Inc.
Smoking Cessation Among Self-Quitters John R. Hughes Departments ofPsychiatry, Psychology, and Family Practice University of Vermont
This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly.
Suzy B. Gulliver University of Vermont
James W. Fenwick Department ofMedical Biostatistics University of Vermont
William A. Valliere, Kevin Cruser, Sara Pepper, and Pam Shea Department ofPsychiatry University of Vermont
Laura J. Solomon University of Vermont
Brian S. Flynn Office on Health Promotion Research University of Vermont We examined cessation among 630 smokers who quit abruptly on their own. Continuous, complete abstinence rates were 33% at 2 days, 24% at 7 days, 22% at 14 days, 19% at 1 month, 11% at 3 months, 8% at 6 months postcessation, and 3% at 6 months with biochemical verification. Slipping (smoking an average of less than 1 cigarette/day) was common (9% to 15% of subjects) and was a strong predictor of relapse; however, 23% of long-term abstainers slipped at some point. These results challenge beliefs that most smokers can initially stop smoking and that most relapse occurs later on postcessation. Key words: nicotine, relapse, self-quitters, smoking
Much of the research in smoking has focused on relapse following initial cessation (Hunt, Barnett, & Branch, 1971; Marlatt & Gordon, 1985). This emphasis has arisen, in part, because much of the existing literature on smoking cessation has been acquired from the fewer than 5% of smokers who received formal behavioral or drug treatments. Initial cessation rates in these studies are often quite high (e.g., 50% to 75%) because subjects are typically highly motivated and received an intensive therapy. Several prospective studies of the 95% of smokers who quit on their own have reported much lower long-term abstinence rates than in clinic attendees (Cohen et al., 1989; Fiore et al., 1990; Schacter, 1982). Initial cessation rates in these studies have not been well described, as the earliest follow-up in most was 1 month postcessation. The purpose of this article is to provide a description of abstinence rates in self-quitters very early on (i.e., 2, 7, 14 and 30 days postcessation).
Requests for reprints should be sent to John R. Hughes, Human Behavioral Pharmacology Lab, Department of Psychiatry, Ira Allen School, University of Vermont, 38 Fletcher Place, Burlington, VT 05401.
METHOD This article reports the abstinence and relapse outcomes for a study of self-quitters. Other papers will report the withdrawal (Hughes, in press) and prediction-of-relapse analyses. Subjects Smokers about to quit "on their own" were recruited through newspaper and radio ads. Subjects were compensated at a rate of $10 for 15 min of interview time. We were able to reach 1,396 (60%) of the 2,349 individuals we called. The major focus of the study was on withdrawal symptoms in self-quitters who stopped abruptly (Hughes, in press); thus, several exclusion criteria were used to select a sample who would be likely to stop abruptly on their own. These criteria excluded 671 smokers (48% of 1,396). The reasons for exclusion were reduced number of cigarettes in past 2 weeks (28% of the 671 excluded subjects), rated motivation to quit less than 5 on a 10-point scale (19%), not presently smoking daily (19%), planned an extended vacation in next few months (13%), recently switched to low-nicotine cigarette in the past 2 weeks (8%), had a quit date more than 100 days from interview
This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly.
332
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(6%), planned to use gradual cessation method (6%), planned to use formal therapy (5%), and was less than 18 years old (1%). Those included and excluded did not differ on demographics or smoking history variables. Six hundred thirty (87%) of the remaining 725 potential subjects were reached for a second baseline interview and still had plans to stop smoking in the next 2 to 10 days. The baseline interviews included brief (less than 10 min) counseling sessions (Hughes & Kottke, 1986). Those reached and not reached for baseline interviews did not differ on demographics or smoking history variables. Among the 630 defined subjects, 65% were women, 55% were married, 92% had completed high school, 38% were in white-collar jobs, and 39% had household incomes of more than $30,000. Mean age was 39 years (SD = 4.9 years). Subjects averaged 26.7 cigarettes/day (SD = 12.3 cigarettes/day) of .85 mg nicotine (SD = .31 mg nicotine) and had smoked for an average of 21.6 years (SD = 11.8 years). Ninety three percent had tried to quit before, 42% smoked within 15 min of arising, and the mean Fagerstrom score for severity of nicotine dependence (Fagerstrom & Schneider, 1989) was 6.2 (SD = 1.8). To estimate the generalizability of our sample, we compared it to average values for samples from (a) 10 studies of self-quitters recently described in Cohen et al. (1989), (b) a random sample of 10 smoking intervention trials that had sample sizes of at least 50 subjects and data on age, sex, and smoking rate selected from the 233 trials listed by Schwartz (1987), and (c) a population-based description of smokers who retrospectively stated they had quit on their own for at least 1 day in the past year (G. Giovino, personal communication, 1991) based on the 1986 National Adult Use of Tobacco Survey conducted by the Centers for Disease Control (Pierce, Hatziandreu, & Flyer, 1986). Our sample and the samples of the 10 prior studies of self-quitters were similar in sex ratio, age, cigarettes/day, percent who had tried to quit before, and percent who smoked within 15 min of arising. Our sample and the samples of the 10 intervention studies were similar in age and cigarettes/day, but our sample included more women (65% vs. 51%, p = .001). Our sample and the populationbased sample of smokers who stated they had tried to quit in 1986 were similar in age, percent married, nicotine yield, and prior quit attempts, but again our sample included more women (65% vs. 47%, p < .001) as well as more white-collar workers (38% vs. 22%, p < .001), and our smokers smoked more cigarettes/day (26.7 vs. 19.8, p < .001). The variables that differed across the populations (sex, occupation, and number of cigarettes/day) did not predict outcome in our sample.
Procedure At the screening interview, subjects named two observers who were older than 18 years and who saw the subject at least 3 hr/day, 5 days/week. After this interview, one of the observers was called to verify how much he or she saw the subject and to obtain the observer's consent to periodically verify abstinence or smoking, for which the observer was paid $3/rating. Subjects and observers were contacted at 2 to 4 days, 7 to 10 days, 14 to 17 days, 30 to 35 days, 90 to 95 days, and 6 months after their quit date. We made up to five attempts to contact a subject or observer at a follow-up, beginning on the first day of the follow-up period. If a subject reported smoking or could not be contacted, his or her observer was not contacted. If the subject reported abstinence
at all follow-ups and was not refuted by the observer, a home visit was made within 30 days after the 6-month follow-up. At the visit, a breath sample for carbon monoxide (CO; Hughes, Frederiksen, & Frazier, 1976) and a saliva sample for cotinine (Jacob, Wilson, & Benowitz, 1981) were obtained. Biochemical cutoffs for defining abstinence at the 6-month follow-up were 10 ppm for CO and 15 Hg/ml for cotinine (Jarvis, Tunstall-Pedoe, Feyerabend, Vesey, & Saloojee, 1987). We used two definitions of abstinence: (a) self-reported, obserververified complete, continuous abstinence and (b) self-reported smoking an average of 1 cigarette/day or less since the last follow-up and observer-verified no smoking more than 10 cigarettes on any 2 days. When observer data were missing, we did not classify smokers as relapsed. Only subjects who met the second definition were continued in the trial. Thus, all abstinence rates reported are continuous rather than point-prevalence rates. We chose not to use the National Heart, Lung, and Blood Institute (NHLBI) criterion of initial cessation and relapse (Ossip-Klein et al., 1986), as this criterion requires 7 days of smoking before a relapse is said to occur; thus, by this criterion, we would have had no relapses at the 2-day follow-up and very few at the 7-day follow-up.
RESULTS Abstinence Using a criterion of complete abstinence, 33% of subjects were abstinent at 2 days, 24% at 7 days, 22% at 14 days, 19% at 1 month, 11% at 3 months, and 8% at 6 months postcessation—95% confidence intervals (CIs ± l%-2%; Figure 1). Using the second, less stringent criterion, 47% of subjects were abstinent at 2 days, 38% at 7 days, 32% at 14 days, 27% at 1 month, 20% at 3 months, and 11% at 6 months postcessation (95% CIs ± l%-2%). Because the NHLBI criterion requires an initial period of abstinence, we recalculated the criterion of complete abstinence using only those who were able to abstain completely from smoking for 48 hr. In these subjects, the rates of complete abstinence would be 74% at 7 days, 68% at 14
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Smoking Cessation Among Self-Quitters John R. Hughes Departments ofPsychiatry, Psychology, and Family Practice University of Vermont
This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly.
Suzy B. Gulliver University of Vermont
James W. Fenwick Department ofMedical Biostatistics University of Vermont
William A. Valliere, Kevin Cruser, Sara Pepper, and Pam Shea Department ofPsychiatry University of Vermont
Laura J. Solomon University of Vermont
Brian S. Flynn Office on Health Promotion Research University of Vermont We examined cessation among 630 smokers who quit abruptly on their own. Continuous, complete abstinence rates were 33% at 2 days, 24% at 7 days, 22% at 14 days, 19% at 1 month, 11% at 3 months, 8% at 6 months postcessation, and 3% at 6 months with biochemical verification. Slipping (smoking an average of less than 1 cigarette/day) was common (9% to 15% of subjects) and was a strong predictor of relapse; however, 23% of long-term abstainers slipped at some point. These results challenge beliefs that most smokers can initially stop smoking and that most relapse occurs later on postcessation. Key words: nicotine, relapse, self-quitters, smoking
Much of the research in smoking has focused on relapse following initial cessation (Hunt, Barnett, & Branch, 1971; Marlatt & Gordon, 1985). This emphasis has arisen, in part, because much of the existing literature on smoking cessation has been acquired from the fewer than 5% of smokers who received formal behavioral or drug treatments. Initial cessation rates in these studies are often quite high (e.g., 50% to 75%) because subjects are typically highly motivated and received an intensive therapy. Several prospective studies of the 95% of smokers who quit on their own have reported much lower long-term abstinence rates than in clinic attendees (Cohen et al., 1989; Fiore et al., 1990; Schacter, 1982). Initial cessation rates in these studies have not been well described, as the earliest follow-up in most was 1 month postcessation. The purpose of this article is to provide a description of abstinence rates in self-quitters very early on (i.e., 2, 7, 14 and 30 days postcessation).
Requests for reprints should be sent to John R. Hughes, Human Behavioral Pharmacology Lab, Department of Psychiatry, Ira Allen School, University of Vermont, 38 Fletcher Place, Burlington, VT 05401.
METHOD This article reports the abstinence and relapse outcomes for a study of self-quitters. Other papers will report the withdrawal (Hughes, in press) and prediction-of-relapse analyses. Subjects Smokers about to quit "on their own" were recruited through newspaper and radio ads. Subjects were compensated at a rate of $10 for 15 min of interview time. We were able to reach 1,396 (60%) of the 2,349 individuals we called. The major focus of the study was on withdrawal symptoms in self-quitters who stopped abruptly (Hughes, in press); thus, several exclusion criteria were used to select a sample who would be likely to stop abruptly on their own. These criteria excluded 671 smokers (48% of 1,396). The reasons for exclusion were reduced number of cigarettes in past 2 weeks (28% of the 671 excluded subjects), rated motivation to quit less than 5 on a 10-point scale (19%), not presently smoking daily (19%), planned an extended vacation in next few months (13%), recently switched to low-nicotine cigarette in the past 2 weeks (8%), had a quit date more than 100 days from interview
This document is copyrighted by the American Psychological Association or one of its allied publishers. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly.
332
HUGHES ETAL.
(6%), planned to use gradual cessation method (6%), planned to use formal therapy (5%), and was less than 18 years old (1%). Those included and excluded did not differ on demographics or smoking history variables. Six hundred thirty (87%) of the remaining 725 potential subjects were reached for a second baseline interview and still had plans to stop smoking in the next 2 to 10 days. The baseline interviews included brief (less than 10 min) counseling sessions (Hughes & Kottke, 1986). Those reached and not reached for baseline interviews did not differ on demographics or smoking history variables. Among the 630 defined subjects, 65% were women, 55% were married, 92% had completed high school, 38% were in white-collar jobs, and 39% had household incomes of more than $30,000. Mean age was 39 years (SD = 4.9 years). Subjects averaged 26.7 cigarettes/day (SD = 12.3 cigarettes/day) of .85 mg nicotine (SD = .31 mg nicotine) and had smoked for an average of 21.6 years (SD = 11.8 years). Ninety three percent had tried to quit before, 42% smoked within 15 min of arising, and the mean Fagerstrom score for severity of nicotine dependence (Fagerstrom & Schneider, 1989) was 6.2 (SD = 1.8). To estimate the generalizability of our sample, we compared it to average values for samples from (a) 10 studies of self-quitters recently described in Cohen et al. (1989), (b) a random sample of 10 smoking intervention trials that had sample sizes of at least 50 subjects and data on age, sex, and smoking rate selected from the 233 trials listed by Schwartz (1987), and (c) a population-based description of smokers who retrospectively stated they had quit on their own for at least 1 day in the past year (G. Giovino, personal communication, 1991) based on the 1986 National Adult Use of Tobacco Survey conducted by the Centers for Disease Control (Pierce, Hatziandreu, & Flyer, 1986). Our sample and the samples of the 10 prior studies of self-quitters were similar in sex ratio, age, cigarettes/day, percent who had tried to quit before, and percent who smoked within 15 min of arising. Our sample and the samples of the 10 intervention studies were similar in age and cigarettes/day, but our sample included more women (65% vs. 51%, p = .001). Our sample and the populationbased sample of smokers who stated they had tried to quit in 1986 were similar in age, percent married, nicotine yield, and prior quit attempts, but again our sample included more women (65% vs. 47%, p < .001) as well as more white-collar workers (38% vs. 22%, p < .001), and our smokers smoked more cigarettes/day (26.7 vs. 19.8, p < .001). The variables that differed across the populations (sex, occupation, and number of cigarettes/day) did not predict outcome in our sample.
Procedure At the screening interview, subjects named two observers who were older than 18 years and who saw the subject at least 3 hr/day, 5 days/week. After this interview, one of the observers was called to verify how much he or she saw the subject and to obtain the observer's consent to periodically verify abstinence or smoking, for which the observer was paid $3/rating. Subjects and observers were contacted at 2 to 4 days, 7 to 10 days, 14 to 17 days, 30 to 35 days, 90 to 95 days, and 6 months after their quit date. We made up to five attempts to contact a subject or observer at a follow-up, beginning on the first day of the follow-up period. If a subject reported smoking or could not be contacted, his or her observer was not contacted. If the subject reported abstinence
at all follow-ups and was not refuted by the observer, a home visit was made within 30 days after the 6-month follow-up. At the visit, a breath sample for carbon monoxide (CO; Hughes, Frederiksen, & Frazier, 1976) and a saliva sample for cotinine (Jacob, Wilson, & Benowitz, 1981) were obtained. Biochemical cutoffs for defining abstinence at the 6-month follow-up were 10 ppm for CO and 15 Hg/ml for cotinine (Jarvis, Tunstall-Pedoe, Feyerabend, Vesey, & Saloojee, 1987). We used two definitions of abstinence: (a) self-reported, obserververified complete, continuous abstinence and (b) self-reported smoking an average of 1 cigarette/day or less since the last follow-up and observer-verified no smoking more than 10 cigarettes on any 2 days. When observer data were missing, we did not classify smokers as relapsed. Only subjects who met the second definition were continued in the trial. Thus, all abstinence rates reported are continuous rather than point-prevalence rates. We chose not to use the National Heart, Lung, and Blood Institute (NHLBI) criterion of initial cessation and relapse (Ossip-Klein et al., 1986), as this criterion requires 7 days of smoking before a relapse is said to occur; thus, by this criterion, we would have had no relapses at the 2-day follow-up and very few at the 7-day follow-up.
RESULTS Abstinence Using a criterion of complete abstinence, 33% of subjects were abstinent at 2 days, 24% at 7 days, 22% at 14 days, 19% at 1 month, 11% at 3 months, and 8% at 6 months postcessation—95% confidence intervals (CIs ± l%-2%; Figure 1). Using the second, less stringent criterion, 47% of subjects were abstinent at 2 days, 38% at 7 days, 32% at 14 days, 27% at 1 month, 20% at 3 months, and 11% at 6 months postcessation (95% CIs ± l%-2%). Because the NHLBI criterion requires an initial period of abstinence, we recalculated the criterion of complete abstinence using only those who were able to abstain completely from smoking for 48 hr. In these subjects, the rates of complete abstinence would be 74% at 7 days, 68% at 14
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