A randomized, controlled trial of NRT-aided gradual vs. abrupt cessation in smokers actively trying to quit

Abstract

Most smoking cessation programs advise abrupt rather than gradual cessation. We conducted a randomized, controlled trial of gradual cessation (n=297) vs. abrupt cessation (n=299) vs. minimal treatment (n=150) among smokers who wanted to quit now and preferred to quit gradually. Participants were recruited via newspaper and radio advertisements. The gradual and abrupt conditions received five phone calls (total=90 min) and the minimal treatment condition received two calls (25 min total). The gradual condition received nicotine lozenge (via mail) to reduce smoking prior to their quit date. After the quit day, all participants received lozenge. The primary outcome was prolonged abstinence from 2 weeks post-quit day through 6 months. Prior to the quit day, the gradual condition decreased cigarettes/day by 54%, whereas the other two conditions decreased by 1% and 5%. Prolonged abstinence rates (CO<10 ppm) did not differ among gradual, abrupt and minimal treatment conditions (4%, 7% and 5%), nor did 7-day point prevalence rates (7%, 11% and 11%). Fewer smokers in the gradual condition (48%) made a quit attempt than in the abrupt (64%) or minimal (60%) conditions (p<.001). In the gradual condition, every week delay to the quit date increased the probability of lapsing by 19% (p<.001). We conclude that among smokers who want to stop gradually in the near future, gradual cessation with nicotine pre-treatment does not produce higher quit rates than abrupt cessation. One liability of gradual reduction may be that it allows smokers to delay their quit date.

Trial registration: ClinicalTrials.gov NCT00297492.

Figure 1

Recruitment and retention flow chart. ITT = intent-to-treat

Figure 2

Treatment schedule

Figure 3

Survival curve of time-to-self-reported first lapse among quit attempters. For those who did not quit or relapsed on the first day of abstinence, we assigned a value of zero. Due to the timing of calls, we sometimes did not inquire about smoking on every day of the study. When post-cessation smoking status was missing due to the study design, we believed using last observation carried backwards was more accurate and more conservative than using last observation carried forward.