Proteins Associated With Social Isolation, Loneliness Identified

MONDAY, Jan. 6, 2025 (HealthDay News) — Proteins associated with social isolation and loneliness are implicated in inflammation, antiviral responses, and complement systems, according to a study published online Jan. 3 in Nature Human Behavior.

Chun Shen, Ph.D., from the Institute of Science and Technology for Brain-Inspired Intelligence at Fudan University in Shanghai, and colleagues characterized the proteomic signatures of social isolation and loneliness through a proteome-wide association study and protein co-expression network analysis leveraging data from 42,062 participants across 2,920 plasma proteins in the U.K. Biobank.

The researchers found that proteins linked to these constructs were involved in inflammation, antiviral responses, and complement systems. During a 14-year follow-up, more than half of these proteins were prospectively linked to cardiovascular disease, type 2 diabetes, stroke, and mortality. Causal relationships were suggested in a Mendelian randomization (MR) analysis from loneliness to five proteins (GFRA1, ADM, FABP4, TNFRSF10A, and ASGR1); colocalization further supported two proteins (ADM and ASGR1). The five MR-identified proteins showed broad associations with other blood biomarkers and with brain volume in regions involved in interoception and emotional and social processes. The relationship between loneliness and cardiovascular diseases, stroke, and mortality was partly mediated by the MR-identified proteins.

“This is the first study delineating robust and comprehensive plasma proteomic signatures associated with social isolation and loneliness. The plasma proteome can help bridge the link between social relationships and morbidity and mortality,” the authors write. “Comprehending the biology underlying the impact of social relationships on health, particularly the peripheral changes preceding disease, may provide new opportunities for targeted prevention and for effective intervention.”

Abstract/Full Text