Structural brain markers are differentially associated with neurocognitive profiles in socially marginalized people with multimorbid illness.

OBJECTIVE: The authors examined associations between complementary fronto-temporal structural brain measures (gyrification, cortical thickness) and neurocognitive profiles in a multimorbid, socially marginalized sample. METHOD: Participants were recruited from single-room occupancy hotels and a downtown community courthouse (N = 299) and grouped on multiple neurocognitive domains using cluster analysis. Subsequently, the authors evaluated whether the fronto-temporal brain indices, and proxy measures of neurodevelopment and acquired brain insult/risk exposure differentiated members of the 3 distinct neurocognitive clusters. RESULTS: Greater frontal and temporal gyrification and more proxies of aberrant neurodevelopment were associated with the lowest functioning neurocognitive cluster (Cluster 3). Further, for older participants (50+ years), increased cortical thickness in frontal regions was associated with the higher functioning neurocognitive cluster (Cluster 1). Finally, the greatest acquired brain insult/risk exposure was associated with the cluster characterized by selective decision-making impairment (Cluster 2). CONCLUSIONS: Fronto-temporal structural brain indices, and proxies of neurodevelopment and acquired brain insult/risk exposure were differentially associated with neurocognitive profiles in socially marginalized persons. These findings highlight the unique pathways to neurocognitive impairment in a heterogeneous population and help to clarify the vulnerabilities confronted by different subgroups. (PsycINFO Database Record