Exploring the associations of plasma proteins with frailty based on Mendelian randomization.

Background: Frailty is an emerging global burden of disease, characterized as an age-related clinical syndrome. Recent studies have suggested a potential link of circulating protein levels with the onset of frailty. This study aims to analyze the potential causal relationships of plasma proteins with frailty using a Mendelian Randomization (MR) study design.

Methods: Associations of plasma proteins with frailty were assessed using inverse variance weighted (IVW), MR-Egger regression, weighted median, maximum-likelihood method, and MR-PRESSO test. Protein-protein interaction network construction and gene ontology functional enrichment analysis were conducted based on MR-identified target proteins.

Results: After false discovery rate (FDR) correction, MR analysis identified five plasma proteins, including BIRC2 [OR = 0.978, 95%CI (0.967-0.990)] and PSME1 [OR = 0.936, 95%CI (0.909-0.965)], as protective factors against frailty, and 49 proteins, including APOB [OR = 1.053, 95%CI (1.037-1.069)] and CYP3A4 [OR = 1.098, 95%CI (1.068-1.128)], as risk factors. Network analysis suggested BIRC2, PSME1, APOE, and CTNNB1 as key intervention targets.

Conclusion: This study employed MR design to investigate the association of circulating plasma proteins with frailty, identified five proteins negatively associated with frailty risk and 49 proteins positively associated with frailty.