Sex Moderates Relationships Between Alcohol Use Disorder, Brain Structure, and Perceived Emotional Support in Young Adults

Objectives: Social support is associated with myriad health benefits, including recovery from alcohol use disorder (AUD). Understanding its neural features may aid in intervention development. However, most neuroimaging studies investigating social support do not consider potential neuroanatomical differences related to sex and AUD, even though both factors have been related to social support. This study investigated neuroanatomical correlates of perceived emotional and instrumental support as a function of sex and lifetime AUD using Human Connectome Project data. Methods: T1-weighted magnetic resonance imaging data were collected. Gray-matter volume in brain regions associated with social support was quantified in a large sample of young adults (522 women and 432 men) who did and did not have a lifetime AUD status. Perceived emotional and instrumental support were determined via self-report scales. Relationships between gray-matter volumes and perceived emotional/instrumental support were determined for each demographic category (women/men, lifetime AUD/no-AUD) via interaction analyses. Results: Gray-matter volumes in 2 brain regions (left rostral anterior cingulate cortex and left lateral orbitofrontal cortex) were inversely associated with perceived emotional support in women with lifetime AUD, such that larger gray-matter volume was associated with lower perceived emotional support. This relationship was not observed in women without lifetime AUD or men with or without lifetime AUD. No associations were observed with instrumental support. Conclusions: Women differ from men in brain-behavior relationships involving perceived emotional support in a manner linked to AUD status. Sex differences warrant further investigation as social support in AUD may operate differently in women and men.