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Published on: May 24, 2017
Use of varenicline for 4 weeks before quitting smoking: decrease in ad lib smoking and increase in smoking cessation
Peter Hajek1, Hayden J McRobbie, Katie E Myers
1United Kingdom Centre for Tobacco Control Studies, Wolfson Institute of Preventive Medicine, Barts and The London School of Medicine and Dentistry, Queen Mary, University of London, London, England.
Background:
The use of varenicline tartrate alleviates postquit withdrawal discomfort, but it also seems to reduce the "reward" associated with smoking. The current treatment schedule, which commences 1 week before quitting, relies primarily on the first mechanism. We set out to determine whether increasing the prequit medication period renders cigarettes less satisfying and facilitates quitting.
Methods:
One hundred one smokers attending a stop-smoking clinic in London, United Kingdom, were randomly allocated to receive varenicline for 4 weeks before the target quit date (TQD) or to receive placebo for 3 weeks before the TQD, followed by varenicline for 1 week before the TQD. In both groups, standard varenicline treatment was given for 3 months after the TQD. Measures included smoking satisfaction and smoke intake before quitting, urges to smoke and withdrawal discomfort after quitting, and sustained abstinence from the TQD to 3 months.
Results:
Varenicline preloading reduced prequit enjoyment of smoking (P = .004) and smoke intake (P < .001), with 36.7% of participants reducing their cotinine concentrations by more than 50% (reducers). Varenicline preloading did not affect postquit withdrawal symptoms, but it increased 12-week abstinence rates (47.2% in the varenicline arm vs 20.8% in the placebo arm, P = .005). The effect was particularly strong among the reducers in the varenicline arm (66.7% in reducers vs 22.6% in nonreducers, P = .002). Varenicline preloading was well tolerated.
Conclusions:
Although several issues remain to be clarified, varenicline preloading can generate a substantial reduction in ad lib smoking and enhance 12-week quit rates. Current treatment schedules may lead to suboptimal treatment results. Trials with longer follow-up periods are needed to corroborate these findings. Trial Registration clinicaltrials.gov Identifier: NCT00789074.
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