Associations between Metabolic Syndrome, Grip Strength, and Depressive Symptom among Community-Dwelling Older Adult: A Cross-Sectional Study

PURPOSE: This study aimed to investigate the influence of muscle strength on the association between metabolic syndrome and depressive symptoms in community-dwelling older adults.METHODS: A cross-sectional survey was conducted on 630 randomly selected community-dwelling older adults aged 65 years and older living in Suwon City. After excluding those younger than 65 years and those with mobility limitations or musculoskeletal disorders, 619 participants were included in the final analysis. The 15-item Center for Epidemiologic Studies Depression Scale was used to assess depressive symptoms. Metabolic syndrome (MetS) was defined based on the National Cholesterol Education Program Adults Treatment Panel III criteria, which included triglyceride (TG), reduced blood high-density lipoprotein (HDL), high blood pressure (BP), elevated fasting plasma glucose, and waist circumference (WC). A digital dynamometer was used to assess grip strength, and the maximum value was determined.RESULTS: Depressive symptoms were significantly associated with relative hand grip strength (RHGS). Specifically, when comparing groups based on the presence of MetS and RHGS levels, grip strength (RHGS) was confirmed to have an important mediating effect on depressive disorders. The following odds ratios (OR) were observed: normal RHGS with metabolic syndrome (OR: 1.859, 95% CI: 0.867-3.985, p=.111), low RHGS without metabolic syndrome (OR: 3.613, 95% CI: 1.735-6.522, p<.001), and low RHGS with MetS (OR: 4.145, 95% CI: 1.687-10.188, p=.002).CONCLUSIONS: Depression appears to have a strong correlation with MetS in adults aged 65 and older. Among the various factors associated with MetS, muscle strength has the closest and most significant association with depressive symptoms. Therefore, implementing strategies to improve muscle strength may be crucial in reducing the likelihood of depression in the elderly population.