Discrepancies in loneliness and social isolation predict cognitive impairment through chronic disease burden

Background: The discrepancy between loneliness and objective social isolation (social asymmetry) has been linked to poorer cognitive aging, yet the biobehavioral pathways underlying this association remain unclear. This study tested whether chronic disease burden or allostatic load mediated associations between social asymmetry and subsequent cognitive performance. Methods: We analyzed data from 840 adults (mean age = 54 years, range = 34-81 years) from the Midlife in the United States (MIDUS) Biomarker Project using structural equation modeling to test parallel mediation through allostatic load and chronic disease burden. Results: : These results point to chronic disease burden, rather than allostatic load, as the primary pathway connecting social asymmetry to cognitive decline. For older adults, reducing chronic disease burden may therefore be one route to preserving cognitive function.