The genetic association analyses were performed on persons with self-identified European ancestry only (Table 1). This included 222 individuals receiving bupropion and 195 individuals receiving placebo. There were slightly more females (54%) than males, and the average age was 44 (SD = 11) years. Similar distributions of the Fagerström Test for Nicotine Dependence (FTND) were observed between the treatment and placebo groups with a mean FTND of 5.1 (SD = 2.1) and 5.2 (SD = 2.2), respectively. At the end of treatment (EOT), there was a 32.0% abstinence rate in the bupropion group when compared with 21.5% in the placebo group. This corresponds to a treatment OR = 1.76 (95% CI 1.12–2.76). Abstinence rates were decreased at 6-month follow-up with 25.7% of those individuals receiving bupropion remaining abstinent and 17.4% of those in the placebo group abstinent (treatment OR = 1.66; 95% CI 1.03–2.69). These treatment effects are consistent with prior research (24). For individuals who relapsed during the 6-month follow-up period, the average for time to first cigarette was 45.2 days (SD = 50.5) in the bupropion group and
