Mental Well-being Crucial for Healthy Aging

In a recent study published in the journal Nature Human Behavior, researchers investigated the causative impact of mental well-being on the genetically independent aging phenotype (aging GIP).

Human life expectancy has improved throughout time, yet the aging population poses issues for individuals and society. Mental well-being is linked to lifestyle habits and morbidity. Studies have connected mental health to improved physical health and survival rates. Furthermore, socioeconomic status (SES) is associated with aging and mental health. However, a causal link between healthy aging and mental well-being has yet to be proven.

Mental Well-being – About the study

The current study investigated the effects of mental well-being on aging phenotypes. This Mendelian randomization (MR) study investigated the causative relationships between aging phenotypes and mental well-being traits, as well as the role of potential mediators in the relationship between aging GIP and the well-being spectrum. Additionally, the team investigated whether the causative effects were SES-independent.

People with European ancestry provided summary-level genome-wide association study (GWAS) data. The exposures included the well-being spectrum, life satisfaction, neuroticism, depressive symptoms, and positive affect. The confounders included three SES indicators: education, occupation, and income. Overall, 106 potential mediators were found for screening; these included 23 lifestyle characteristics, 20 physical function traits, 53 illnesses, and ten behaviors and performances.

Mediators were chosen using a set of criteria: the mediator should have a causal association with aging GIP and a direct causal effect independent of the well-being spectrum; the well-being spectrum should have a causal association with the mediator (but not vice versa); and the association between the mediator and aging GIP and the well-being spectrum with the mediator should be in the same direction.

Outcomes included the aging GIP and its components. Linkage disequilibrium score regression was used to investigate genetic relationships between mental health features, aging phenotypes, and socioeconomic status indicators. Univariable MR (UVMR) analysis was used to determine the causal effect of mediators and mental well-being qualities on aging phenotypes.

UVMR and multivariable MR (MVMR) analyses were used to determine the causal impact of SES markers on mental health features. The MVMR analysis, corrected for SES indicators, investigated the direct impact of the well-being spectrum on aging phenotypes. A two-step MR analysis examined the mediating effect(s) of the well-being spectrum on aging GIP.

Findings

Except for longevity, all mental well-being measures showed genetic connections with the aging GIP and its components. The well-being spectrum was connected with a higher aging GIP. The well-being spectrum consistently demonstrated favorable causal relationships with resilience, health span, parental lifespan, and self-rated health.

Positive affect and life satisfaction were positively connected with these aging phenotypes, but depressive symptoms and neuroticism were adversely related. SES indices and well-being characteristics were also linked. Higher income, education, and occupation were all connected with better mental health. Even after controlling for SES variables, the well-being spectrum was associated with increased aging GIP.

Of the 106 potential mediators, 33 met the screening criteria and were selected. Unhealthier lifestyle characteristics,

physical functions, behaviors, and performances were linked to decreased aging GIP. Higher aging GIP was associated with later smoking initiation age, increased cheese consumption, appendicular lean mass (ALM), cognitive function, high-density lipoprotein cholesterol (HDL-C), and fresh fruit intake.

Heart failure, hypertension, stroke, and coronary heart disease exhibited the most significant effects on the aging GIP. Antihypertensive medicine, smoking initiation age, and television viewing time each accounted for at least 7% of the effect of the well-being spectrum on the aging GIP. Non-steroidal anti-inflammatory medicines, waist-to-hip ratio, fresh fruit intake, ALM, HDL-C, triglycerides, and age of menarche each accounted for up to 4.81% of the overall effect.

Conclusions

In conclusion, the study demonstrated the causal impacts of mental well-being on aging phenotypes that are independent of socioeconomic status. Better mental health was linked to improved aging GIP. The causative influence was partially explained by 33 mediators, which included lifestyles, physical functions, diseases, and behaviors and performances. Overall, the findings emphasize the importance of putting mental health first when it comes to good aging.

For more information: Ye CJ, Liu D, Chen ML, et al. Mendelian randomization evidence for the causal effect of mental well-being on healthy aging. Nat Hum Behav, 2024, DOI: 10.1038/s41562-024-01905-9, https://www.nature.com/articles/s41562-024-01905-9