The following is a summary of “Causal relationship between genetically predicted mental disorders and frailty: a bidirectional and multivariable mendelian randomization study,” published in the December 2024 issue of Psychiatry by Sun et al. 

Researchers conducted a retrospective study to explore the causal relationship between mental disorders and frailty. 

They conducted a 2-sample mendelian randomization (MR) study to assess the causal relationship between frailty, measured by the frailty index (FI), and 10 common mental disorders. The analysis included European ancestry individuals, with the FI measured in 175,226 participants, and mental disorder datasets comprising schizophrenia (SCZ; N = 320,404), major depressive disorder (MDD; N = 143,265), bipolar disorder (337,199), insomnia (462,341), obsessive-compulsive disorder (33,925), anxiety disorders (463,010), autism spectrum disorder (46,351), anorexia nervosa (14,477), opioid-related disorders (215,650), and stimulant-related mental disorders (215,570). 

The results showed that genetically predicted SCZ (odds ratio [OR] = 1.019, 95% CI 1.005–1.033) and MDD (OR = 1.211, 95% CI 1.092–1.343) had significant causal effects on FI. In reverse MR, MDD was significantly affected by FI (OR = 1.290, 95% CI 1.133–1.469). No causal links were found between FI and the other eight mental disorders. In the Multivariable MR, the MDD effect on FI (OR = 1.298, 95% CI 1.175–1.435) was consistent with the univariate estimate, while the SCZ effect was not significant. Sensitivity and validation analyses confirmed stabilization. 

Investigators found a causal relationship between SCZ, MDD, and frailty, with MDD showing a stronger effect.  

Source: bmcpsychiatry.biomedcentral.com/articles/10.1186/s12888-024-06409-4