Romantic relationships and substance use in early adulthood: an examination of the influences of relationship type, partner substance use, and relationship quality.

This study used longitudinal data from 909 young adults to examine associations between substance use and the status and quality of romantic relationships. Heavy alcohol use, marijuana use, and cigarette smoking, as well as relationship status, relationship quality, partner substance use, and other salient life circumstances were assessed at four time points in the two years after high school. Marriage, cohabiting relationships, and noncohabiting dating relationships were associated with reductions in heavy drinking and marijuana use relative to non-dating, after adjusting for adolescent substance use; marriage compared to not dating was associated with reductions in cigarette smoking. For those in romantic relationships, partner substance use moderated the associations between relationship quality and substance use for heavy drinking and for marijuana use, supporting the hypothesis derived from the Social Development Model that the protective effect of stronger social bonds depends on the use patterns of the partner to whom an individual is bonded.