Handgrip strength predicts incident depression in Chinese older adults: a national prospective cohort study

BACKGROUND: Depression in older adults is a major global public health challenge. As an indicator of muscular strength, handgrip strength (HGS) is associated with various health outcomes. However, the longitudinal association of HGS with depression, as well as the sex difference of such an association, remains unclear. This study aims to explore the association between HGS and depression among older adults in China and the underlying mechanism. METHODS: 2,016 participants aged ≥ 60 years were enrolled from the China Health and Retirement Longitudinal Study (CHARLS) (2011–2018), a prospective cohort, excluding those with baseline depression. HGS was measured in a standardized manner using a mechanical dynamometer. Depression was assessed using the 10-item Center for Epidemiologic Studies Depression Scale (with scores ≥ 10 defined as depression). Multivariable logistic regression, restricted cubic spline, and sex-stratified analyses were employed to examine the associations, adjusting for potential confounders such as demographic characteristics, chronic diseases, and biomarkers. RESULTS: During the 7-year follow-up period, 571 new cases of depression were identified. Participants in the lower quartile of HGS (Q1) had a significantly increased risk of depression (OR = 2.10, 95% CI: 1.44–3.06), demonstrating a reverse “J-shaped” dose–response relationship (P < 0.01). Sex-stratified analyses revealed that reduced HGS was associated with a higher risk of depression in males (Q2: OR = 1.73, 95% CI: 1.15–2.60), while no significant association was found in females. Sensitivity analyses confirmed the robustness of the findings. CONCLUSION: HGS is an independent predictor of depression in older adults. It is recommended that HGS be incorporated into health screening for older adults.