Associations of social network size and perceived level of social support with age acceleration estimated by a proteomic aging clock: the Atherosclerosis Risk in Communities Study.

We examined the associations of social network size and social support with biological age acceleration using a protein-based aging clock. A total of 11 719 participants (mean age, 57.1 ± 5.7 years; 55.6% female) of the Atherosclerosis Risk in Communities (ARIC) study Visit 2 (1990-1992) were included. Biological age was calculated using a proteomic aging clock (PAC), and age acceleration was defined as the residuals after regressing the PAC on chronological age. The associations of self-reported social network size and level of support with standardized mean age acceleration were examined using multivariable linear regression. Size of social networks and level of support were inversely associated with age acceleration. The age accelerations of small, medium, and large social networks were 0.24, 0.08, and -0.05 (P for trend = 0.003), while for low, moderate, and high levels of support the age accelerations were 0.33, 0.19, and -0.06 (P for trend < 0.0001), respectively. Associations were modestly attenuated after adjusting for social and lifestyle factors. Findings of the benefit of social networks and support to biological aging processes provide evidence of potential physiological underpinnings of social interactions on health outcomes.