OROS-methylphenidate or placebo for adult smokers with attention deficit hyperactivity disorder: Racial/ethnic differences

ObjectiveTo explore racial/ethnic difference in OROS-methylphenidate (OMPH) efficacy when added to nicotine patch and counseling for treating nicotine dependence among smokers with attention deficit hyperactivity disorder (ADHD).MethodParticipants were adult smokers with ADHD (202 whites and 51 non-whites) randomly assigned to OMPH or placebo in a multi-site, randomized controlled trial. Study outcomes were complete, prolonged, and point-prevalence abstinence at the end of treatment, and weekly ratings of ADHD symptoms, tobacco withdrawal symptoms, and desire to smoke.ResultsThe rate of four-week complete abstinence (no slips or lapses) was significantly higher with OMPH than placebo among non-white (OMPH = 42.9%, placebo = 13.3%, χ2(1) = 5.20, p = 0.02) but not white participants (OMPH = 23.1%, placebo = 23.5%, χ2(1) = 0.00, p = 0.95). Patterns of prolonged and point-prevalence abstinence among non-whites were similar but fell short of statistical significance. OMPH reduced ADHD symptoms in both race/ethnic groups, and produced greater reductions in desire to smoke and withdrawal symptoms among the non-white than white participants. Change in desire to smoke, but not in withdrawal or ADHD symptoms predicted abstinence. The ability of OMPH to reduce desire to smoke among non-whites appeared to mediate the medication's positive effect on abstinence.ConclusionDifferential efficacy favoring non-whites of a medication for achieving smoking cessation is a potentially important finding that warrants further investigation. OROS-MPH could be an effective treatment for nicotine dependence among a subgroup of smokers.