Subgroups of smokers with different success rates after use of transdermal nicotine

To identify subgroups of smokers with different success rates, we applied "tree-structured survival analysis" (TSSA) to data from a previously published trial of transdermal nicotine. The subjects who received active treatment (14 mg patch, n = 275, or the 21 mg patch, n = 262) constituted the sample for this analysis. Using age, gender, the Fagerstrom Tolerance Questionnaire (FTQ), motivation to quit, number of cigarettes smoked at baseline, and body mass index (BMI) as classification variables, TSSA identified two subgroups within the 14 mg patch group and four subgroups of smokers within the 21 mg patch group. Among those receiving the 14 mg patch, individuals with a BMI greater than 26.4 kg/m2 relapsed sooner than did those with a BMI less than or equal to this value. Within the 21 mg patch group, the survival curve for males was significantly different from that observed in females, with males experiencing a longer time to relapse after treatment than did females. Among females, those with a higher motivation to quit relapsed more slowly than did those women with less motivation to quit. This information may be helpful to clinicians seeking to match specific patients to specific treatments with traditional nicotine in order to maximize treatment outcomes.