Time-varying mediated effects of the nicotine patch on smoking before and after a quit attempt when it is added to varenicline and counseling.

Abstract

Even with evidence-based treatment, most people who try to quit smoking return to regular smoking within weeks. Mediation analyses simultaneously test hypotheses about how treatments affect possible smoking determinants and how these determinants may influence smoking risk. Such evidence may inform treatment enhancement. Conduct secondary analyses that assess the extent to which: a) active vs. placebo nicotine patch used in conjunction with varenicline and counseling affect candidate mediators in the peri-cession period, b) candidate mediators predict next-day smoking, and c) treatment effects on next-day smoking are mediated via candidate mediators. Time-varying mediation models (TVMM) were fit to ecological momentary assessment data collected nightly from 1202 adults motivated to quit smoking in the 2 weeks preceding and 2 weeks following the target date to quit smoking in a placebo-controlled, double-blinded randomized controlled trial of adjuvant nicotine patch therapy used with varenicline and individual counseling. Analyses confirmed the predictive value of hypothesized mediators (cravings to smoke, nicotine withdrawal symptoms, reduced positive affect, and low quitting confidence) on next-day smoking risk, but also found that only positive affect mediated active (vs. placebo) patch effects on next-day abstinence 3-9 days after a target quit day. Adding nicotine patches to varenicline and counseling improves positive affect in ways that predict lower next-day smoking risk in the first days of attempts to quit smoking but does not significantly improve withdrawal management or sustain confidence in quitting.