摘要：Objectives. We evaluated smoking-cessation efficacy of an extended course of sustained-release bupropion (bupropion SR) and cognitive-behavioral treatment (CBT). Methods. Participants who smoked at least 10 cigarettes per day and who smoked within 30 minutes of arising (n = 406) completed a 12-week smoking-cessation treatment including group counseling, nicotine-replacement therapy, and bupropion SR. Participants were then randomly assigned to 1 of 5 conditions: (1) no further treatment, (2) active bupropion SR for 40 weeks, (3) placebo for 40 weeks, (4) active bupropion SR and 11 sessions of CBT for 40 weeks (A-CBT), or (5) placebo and 11 sessions of CBT for 40 weeks. Participants were assessed at baseline and at weeks 12, 24, 52, 64, and 104. Results. A-CBT was not superior to the other 3 extended treatments. From weeks 12 through 104, all extended treatment conditions were superior to standard treatment. At weeks 64 and 104, the 2 CBT conditions produced significantly higher abstinence rates than did the other 3 conditions. Conclusions. Brief contact with providers can increase abstinence during treatment. CBT may increase long-term abstinence after extended treatment is terminated. Researchers and clinicians have come to expect low rates of long-term cigarette abstinence subsequent to tobacco-dependence treatment—usually 25% or less at 1 year, even with combination therapy. 1 , 2 These low rates may be attributable to a failure to conceputalize tobacco dependence as an addiction with a chronic, relapsing course. The implications of a chronic-disease model suggest that longer, more extended courses of tobacco-dependence treatment may result in higher long-term cigarette abstinence rates. Three studies have examined the efficacy of extended administration of sustained-release bupropion (bupropion SR). Hays et al. treated participants for 7 weeks with open-label bupropion SR and then randomly assigned only cigarette-abstinent participants (59% of the sample) to active or placebo bupropion SR for an additional 45 weeks. Cigarette abstinence was significantly higher in the active drug condition (55.1%) than in the placebo drug condition (42.3%) after 1 year of therapy, but the conditions did not differ at 2-year follow-up (41.6% for active drug; 40.0% for placebo). 3 In a second study, smokers were treated with nicotine patches calibrated to individual cigarette intake. Abstinent participants (31% of the sample) were then randomly assigned to either active or placebo bupropion SR for 6 months. Abstinence rates did not differ between conditions at 6 months (25% for placebo; 28% for active drug). 4 Cox et al. 5 randomized abstinent smokers who had been treated with 7 weeks of bupropion SR to either continued bupropion SR for the remainder of 1 year or to placebo. Active drug produced greater cigarette abstinence at the end of treatment when compared with placebo (55.89% vs 43.58%), but there were no differences at 1-year follow-up (42.34% vs 42.95%). Thus, it appears that extended bupropion SR provides an increase in abstinence rates while being administered, but this effect is lost after medication termination. Extended administration of varenicline has also been studied. Williams et al. administered either varenicline or placebo over 1 year and found that varenicline was superior to placebo at both 12 weeks (76.5% to 72.2%) and 52 weeks (37.8% to 34.1%). 6 Tonstad et al. 7 randomized abstinent smokers who had been treated with 12 weeks of varenicline to either continued varenicline or to placebo for an additional 12 weeks. Continuous cigarette abstinence rates were higher for the varenicline group than for the placebo group for weeks 13 through 24 (70.5% to 49.6%) and for weeks 13 through 52 (43.6% to 36.9%). Thus, the therapeutic effects of extended varenicline may last past the period of administration. In earlier work, our group studied extended administration of nortriptyline. We assigned smokers to 1 of 4 treatment conditions in a 2 × 2 factorial design (nortriptyline vs placebo by brief treatment vs extended treatment). Participants in extended treatment continued taking drug or placebo and received monthly individual counseling sessions through week 52. At week 52, abstinence rates were 56% for extended nortriptyline and 57% for extended placebo. Both conditions produced abstinence rates that exceeded those of short-term treatment. Three studies have investigated the effects of extended cognitive-behavioral treatment (CBT). Killen et al. 8 treated smokers for 12 weeks with open-label bupropion SR, nicotine patch, and weekly relapse-prevention training. All participants, independent of smoking status, were then offered 4 relapse-prevention sessions and continued on either active or placebo drug for an additional 14 weeks. There were no differences in abstinence rates between conditions at 1 year. In a second study 9 participants received bupropion SR, nicotine patch, and CBT for 8 weeks and were then randomly assigned to receive either 12 weeks of CBT plus voicemail monitoring and telephone counseling or telephone-based general support. The investigators reported significant differences at 20 weeks (45% vs 29%) but not at 52 weeks (31% vs 27%). Recently, we studied 402 people who smoked at least 10 cigarettes per day and who were 50 years old or older. 10 All completed a 12-week treatment that included group counseling, nicotine gum, and bupropion SR, and all were then randomly assigned to 1 of 4 follow-up conditions: (1) standard treatment (no further treatment), (2) extended nicotine-replacement therapy (NRT) with 40 weeks of nicotine gum availability, (3) extended CBT (11 cognitive behavioral sessions over a 40-week period), or (4) extended CBT plus extended NRT (11 CBT sessions plus 40 weeks of nicotine gum availability). The extended CBT condition produced high cigarette-abstinence rates that were maintained throughout the 2-year study period (week 24 = 58.3%; week 52 = 55.0%; week 64 = 54.6%; week 104 = 54.8%). The extended CBT condition was significantly more effective than extended NRT and standard treatment across that period. No other treatment condition was significantly different from standard treatment. These findings suggest that extended CBT can produce high and stable cigarette abstinence rates. Medication does not appear to play a major role in maintaining abstinence when combined with CBT. In the current study, we evaluated a CBT intervention similar to that described by Hall et al. 10 We also evaluated the efficacy of long-term bupropion SR versus placebo. We proposed the following hypotheses: (1) at all assessments after baseline, the active bupropion extended CBT (A-CBT) condition would produce higher point prevalence abstinence rates than placebo with extended CBT (P-CBT), placebo alone, active bupropion alone, or standard treatment (our primary hypothesis); and (2) at all assessments after the end of extended treatment, the 2 conditions that included CBT (combined with active or placebo bupropion) would produce abstinence rates superior to those produced by the 3 conditions that did not include CBT.
