We conducted a review of published reports of smoking cessation pharmacotherapy trials in order to address the following: 1) the generalizability of findings to smokers with a history of alcohol problems; 2) the extent to which alcohol use affects smoking cessation overall and the efficacy of pharmacotherapy specifically and 3) the effect of smoking cessation on alcohol use.
We located published reports of nicotine replacement therapy (NRT), bupropion sustained release (SR) and varenicline clinical trials using an approach based on prior Cochrane reviews. The reports were searched for alcohol-related inclusion/exclusion criteria and for findings related to alcohol.
The present review included 212 published reports from 149 trials. Alcohol-related exclusion criteria appeared frequently (41.6% of trials)—45/125 NRT trials (36%), 15/22 bupropion SR trials (68.2%) and 3/3 varenicline trials—and most commonly involved exclusion of participants with either current or recent alcohol problems. Most studies failed to provide any baseline alcohol-related characteristics. Eleven trials reported on the relationship between alcohol history and likelihood of smoking cessation. In the majority of these studies, smokers with a past history of alcohol problems were not at a disadvantage, although contrary findings exist. Only two studies examined the potential influence of smoking cessation on alcohol use.
Smokers with alcohol problems, particularly those with current or recent problems, are underrepresented in studies of approved pharmacotherapy for smoking cessation. Future trials should assess alcohol use at baseline and during treatment and examine reciprocal influences between alcohol consumption and smoking cessation.