Race moderates the effects of Motivational Interviewing on smoking cessation induction

Across many outcomes, participant race interacted with the type of treatment. In African Americans, health education outperformed motivational interviewing. Race effects were accounted for by relationship status and communication preference. Health disparities necessitate exploration of how race moderates response to smoking cessation treatment. Data from a randomized clinical trial of Motivational Interviewing (MI) for smoking cessation induction were used to explore differential treatment response between African American (AA) vs Non-Black (NB) smokers. Adult tobacco smokers (138 AA vs 66 NB) with low desire to quit were randomly assigned to four sessions of MI or health education (HE). Outcomes (e.g., quit attempts) were assessed 3- and 6-months. There was evidence of a Race by Treatment interaction such that MI was less effective than HE in AA smokers. Mean Cohen's d for the interaction effect was −0.32 (95% CI [−0.44, −0.20]). However, the race interaction could be accounted for by controlling for baseline relationship status and communication preference (wants directive approach). MI may be less effective for smoking cessation induction in AA vs NB smokers when compared to another active and more directive therapy. The differential response between races may be explained by psychosocial variables. MI may not be an ideal choice for all African American smokers. Patients' relationship status and preference for a directive counseling approach might explain disparities in response to MI treatment.