Characterizing the Impact of Dyadic Motivations to Quit on Cessation Outcomes in Dual-Smoking Couples

Introduction: Among dual-smoking couples, both partners have smoking-related motivations that may either facilitate or hinder cessation efforts. Existing research typically focuses on individual-level motivation, which may be inadequate for capturing aspects of concordance and discrepancy. This study characterized couples' motivational profiles and examined their associations with smoking cessation outcomes. Methods: We conducted secondary analyses from a randomized controlled pilot study of 95 dual-smoking couples to examine how dyadic motivations to quit smoking predicted individual and joint point-prevalence abstinence at 3 months. Both partners reported their own motivation to quit (self-oriented) and their motivation for their partner to quit (partner-oriented). We examined dyadic motivation to quit smoking on abstinence across four goal characterizations: (1) Parallel Goals (partners' self-oriented motivations), (2) System-Oriented Goals (an individual's self- and partner-oriented motivation), (3) Shared Target Goals (both partners' motivation for one individual to quit), and (4) Parallel Partner-Oriented Goals (each partner's motivation for the other to quit). Using response surface analyses with logistic regression, we estimated the effects of alignment (a₁) and misalignment (a₂) in the couples'' motivation levels on individual and joint cessation outcomes. Results: For individual cessation, quitting odds were higher when self-motivation or partner-oriented motivation aligned within the couple (Parallel goals: a₁ = 0.725; Shared Target goals: a₁ = 0.881; Parallel Partner-Oriented goals: a₁ = 0.729), when self-motivation exceeded partner's self-motivation (Parallel goals: a₃ = 0.453), or exceeded partner-oriented motivation (System-Oriented goals: a₃ = 1.094). Joint quitting was more likely when both partners had high self-motivation (Parallel goals: a₁ = 0.918), high self- and partner-oriented motivation (System-Oriented goals: a₁ = 0.310), high shared motivation for one partner to quit (Shared Target goals: a₁ = 0.673), or high partner-oriented motivation for each other (Parallel Partner-Oriented goals: a₁ = 0.965). All effects were statistically significant (P < .05). Conclusion: The findings highlight the role of dyadic motivations in predicting individual and dyadic abstinence among dual-smoking couples. Couple-based interventions that aim to increase and align partners' motivations to quit could improve cessation outcomes in this population.