Importance: The efficacy of nicotine replacement therapy (NRT) is well demonstrated in clinical trials in which NRT is accompanied by behavioral support. Epidemiologic data, however, indicate that people using NRT are no more likely to successfully quit smoking than those who do not use NRT.
Objective: To evaluate the effect of mailing nicotine patches to smokers without behavioral support on quit success rates.
Design, setting, and participants: A single-blinded, 2-group randomized clinical trial of adult smokers recruited across Canada by random-digit dialing of home and cell telephone numbers from June 4, 2012, through June 26, 2014. Follow-up was completed on January 5, 2015, and data were analyzed from May 24, 2015, through July 6, 2015. A total of 2093 individuals who smoked more than 10 cigarettes per day were interviewed at baseline and asked if they would be hypothetically interested in receiving nicotine patches by mail to quit smoking. Those who were interested and deemed eligible to participate (no contraindications to NRT) were randomized to the experimental group to be mailed a 5-week supply of nicotine patches or to a control group. Telephone follow-ups were conducted at 8 weeks and 6 months.
Interventions: Participants in the experimental group were sent a 5-week course of nicotine patches by expedited postal mail (3 weeks of step 1 [21 mg of nicotine], 1 week of step 2 [14 mg of nicotine], 1 week of step 3 [7 mg of nicotine], no behavioral support provided). Participants randomized to the control group were not offered the nicotine patches or any other intervention.
Main outcomes and measures: The primary outcome was 30-day smoking abstinence at 6 months.
Results: Of the 2093 participants who were interviewed as part of the baseline survey (76.5% response rate), 1000 were found eligible for the trial and randomized to a group. Analyses were conducted on 500 participants in the experimental group (mean [SD] age, 48.0 [12.8] years; 255 female [51.0%]) and 499 in the control group (mean [SD] age, 49.7 [12.7] years; 256 female [51.3%]). Self-reported abstinence rates were significantly higher among participants who were sent nicotine patches compared with the control group (30-day abstinence: 38 [7.6%] of 500 vs 15 [3.0%] of 499; odds ratio, 2.65; 95% CI, 1.44-4.89; P = .002). Usable saliva samples were returned by only 50.9% of the participants. Biochemically validated abstinence at 6 months was found in 14 (2.8%) of 500 participants in the experimental group vs 5 (1.0%) of 499 in the control group (odds ratio, 2.85; 95% CI, 1.02-7.96; P = .046).
Conclusions and relevance: The trial provides evidence of the effectiveness of mailed nicotine patches without behavioral support to promote tobacco cessation. The strength of these findings is tempered by the lack of biochemical validation for all participants.
Trial registration: clinicaltrials.gov Identifier: NCT01429129.