Relationship intervention moderates the association between substance use and biological aging among Black adults.

Objective: Black Americans face disproportionate challenges related to substance use and the health impacts of substance use, including accelerated aging. Accordingly, interventions are needed to protect against the harmful effects of substance use on accelerated aging. The present study examined whether the Protecting Strong African American Families (ProSAAF) intervention, a relationship education program designed to promote strong relationships among Black families, moderated the association between substance use and accelerated aging among Black couples.

Method: Black couples received either the ProSAAF intervention or a minimal-touch control intervention and provided deoxyribonucleic acid specimens for methylation-based biomarker measurements of alcohol use and cigarette smoking (Alcohol T scores and cg05575921, combined into a substance use composite) and accelerated aging (DNAm GrimAge) 6- and 9 years postintervention.

Results: Participants receiving the ProSAAF intervention (relative to the control condition) experienced a significantly weaker association between substance use and accelerated aging. Among the participants who were in the same relationship as when they were initially randomized, the association between substance use and aging was significantly weaker in the ProSAAF condition than in the control condition for participants with lower relationship satisfaction preintervention; no differences emerged among those with higher satisfaction.

Conclusions: ProSAAF mitigated some of the harmful effects of substance use on accelerated aging among Black couples, particularly among those with lower preintervention relationship satisfaction. These findings highlight the potential for relationship interventions to serve as sources of constructed resilience that promote healthier aging. (PsycInfo Database Record (c) 2025 APA, all rights reserved).