Associations Between Negative Social Ties and Accelerated Biological Aging, Inflammation, and Multiple Morbidities

Negative social ties, or "difficult ties," are pervasive yet understudied components of social networks that may accelerate biological aging and morbidity. Using ego-centric network data and DNA methylation-based biological aging clocks from a state representative probability sample in Indiana, we examine how negative social ties are associated with accelerated biological aging and a broad range of adverse physical and mental health outcomes. First, we find that difficult social ties are surprisingly common: on average, one in four network members is described as difficult, and nearly 60% of individuals report having at least one difficult tie. Regression analyses show that having more negative ties is associated with accelerated biological aging, with the most pronounced associations observed among individuals whose networks comprise more than 50% difficult ties. Finally, having negative ties is also associated with multiple adverse health outcomes beyond epigenetic aging, including poorer self-rated health, higher levels of depression and anxiety, elevated inflammation, greater multimorbidity, and unfavorable anthropometric indicators such as increased waist-to-hip ratio and BMI. These findings together highlight the critical role of negative social ties in biological aging as chronic stressors and the need for interventions that reduce the impact of negative social stressors within close social networks to promote healthier aging trajectories.