Cue reactivity as a predictor of successful abstinence initiation among adult smokers.

The association between smokers' cue-induced craving and subsequent ability to initiate abstinence is unclear. Dependent smokers (N = 158) completed a single cue-reactivity session prior to participating in a larger within-subjects study, which independently examined predictors of initiating quitting during 5 days each on nicotine versus placebo patch. In the larger study, all smokers used nicotine and placebo patch (double blind) for 1 week each following a preceding week of ad lib smoking, in a 2 × 2 cross-over design. Generalized estimating equation (GEE) models determined the predictive ability of cue-induced craving (cue reactivity) on subsequent success at initiating a quit attempt (at least 24 hr quit) for each patch condition. Smokers who exhibited greater craving during exposure to smoking cues had significantly greater odds of successfully initiating abstinence during either quit attempt week (i.e., the nicotine or placebo patch week). This relationship was not statistically significant for self-reported craving in response to neutral cues. However, a greater smoking-neutral cue difference score for cue-induced craving was also a significant predictor of successfully initiating abstinence, but only among those not monetarily reinforced. Implications of these seemingly counterintuitive findings are discussed.

Is self-efficacy for smoking abstinence a cause of, or a reflection on, smoking behavior change?

Social learning theory considers self-efficacy as a causal factor in behavior change. However, in line with behavioral theory, recent clinical research suggests self-efficacy ratings may reflect, rather than cause, behavior change. To test these two disparate views, self-efficacy was related to actual smoking abstinence on the next day (i.e., self-efficacy causes change), and abstinence status over 1 day was tested as a predictor of rated self-efficacy for quitting the next day (i.e., reflects change). All data were from two similar crossover studies evaluating the short-term effects of both placebo versus medication, nicotine patch (n = 209) or varenicline (n = 123), on smoking abstinence during week-long practice quit attempts. Placebo and active medication periods were separated by an ad lib smoking washout, and analyses were controlled for prior-day's abstinence or self-efficacy values. Results were very consistent between studies in showing essentially bidirectional associations: daily self-efficacy predicted next-day's abstinence, and current-day's abstinence status predicted self-efficacy for abstinence the next day. However, secondary factors differentially predicted abstinence and, to a lesser extent, self-efficacy, between these two medication studies. These data provide some support for both social learning and behavioral theories of smoking behavior change, although self-efficacy may only briefly predict subsequent short periods of abstinence as assessed in these studies. Nonetheless, because self-efficacy has long been assumed to cause behavior change, including smoking cessation, the notion of self-efficacy as a reflection of recent smoking behavior change in these studies warrants greater attention in clinical research on smoking cessation treatment.

Varenicline's effects on acute smoking behavior and reward and their association with subsequent abstinence.

RATIONALE: Varenicline may aid smoking cessation by attenuating smoking behavior and reward. We compared the effects of varenicline versus placebo on smoking behavior and reward, assessed both prospectively and retrospectively, and related these effects to subsequent success in a brief simulated quit attempt with medication. MATERIALS AND METHODS: Smokers (n = 124) with high or low interest in quitting smoking participated in a double-blind crossover study of varenicline versus placebo effects on smoking behavior and reward. In each of two phases, subjects received a week of medication run-up with varenicline (0.5 mg, b.i.d.) or placebo while continuing to smoke, followed the next week by an attempt to quit while on medication. At the end of each run-up week, subjects completed retrospective measures of smoking reward (liking) and number of cigarettes over the prior 24 hrs, and they provided an expired air carbon monoxide (CO) measure. They then completed a prospective session in which they ad lib smoked and rated the rewarding effects of one of their preferred cigarettes while blind to brand. RESULTS: Varenicline decreased smoking reward significantly in the prospective assessment, but only marginally in the retrospective assessment. Varenicline did not alter smoking behavior prospectively, but did reduce CO and retrospective report of smoking amount. None of these effects of varenicline predicted subsequent days of abstinence due to varenicline. CONCLUSIONS: During medication run-up, varenicline decreases acute smoking reward and may attenuate smoking behavior, but these effects do not appear to directly predict varenicline's influence on smoking abstinence in a short-term test.

Nicotinic acetylcholine receptor beta2 subunit (CHRNB2) gene and short-term ability to quit smoking in response to nicotine patch.

Genes coding for nicotinic acetylcholine receptors may influence response to nicotine replacement therapy for smoking cessation. We examined the association of a 3' untranslated region polymorphism (rs2072661) in the nicotinic acetylcholine receptor beta2 subunit (CHRNB2) gene with quitting success in response to nicotine versus placebo patch during a short-term test of patch effects. In a within-subjects cross-over design, smokers of European descent (n = 156) received 21 mg nicotine and placebo patch in counter-balanced order, during two separate 5-day simulated quit attempts, each preceded by a week of ad libitum smoking. Abstinence was assessed daily by CO < 5 ppm. Smokers with the CHRNB2 GG genotype had more days of abstinence during the nicotine versus placebo patch week compared with those with the AG or AA genotypes (P < 0.01). Moreover, nicotine patch increased the probability of quitting on the target quit day, quitting anytime during the patch week, and avoiding relapse among those with the GG genotype but not the AA/AG genotypes, although the nicotine x genotype interaction was significant only for quitting on the target quit day (P < 0.05). Regardless of patch condition, quitting on the target quit day was more likely in those with the GG genotype versus AA/AG genotypes (P < 0.05). Genetic associations were not observed for craving or withdrawal responses to nicotine versus placebo patch. These findings are consistent with previous evidence of association of this variant with smoking cessation and suggest that polymorphisms in the nicotinic acetylcholine receptor beta2 subunit gene may influence therapeutic responsiveness to cessation medications.