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

Abstract

Objective: To 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).

Method: Participants 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.

Results: The 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%, chi(2)(1)=5.20, p=0.02) but not white participants (OMPH=23.1%, placebo=23.5%, chi(2)(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.

Conclusion: Differential 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.

Trial registration: ClinicalTrials.gov NCT00253747.

Figure 1

Symptom scores from baseline to the end of treatment. Numbers on the x-axis indicate the week on which each measure was obtained. Non-white (triangles), white (circles), OMPH (—), placebo (- -)