Associations between grip strength and generalized anxiety disorder in older adults: Results from the Irish longitudinal study on ageing

Background: Associations between grip strength and mental health disorders have been established; however, associations between grip strength and Generalized Anxiety Disorder (GAD) remain unstudied. Therefore, this study investigates associations between grip strength and prevalent and incident GAD. Methods: A prospective cohort design was utilized. At baseline, participants aged ≥50 years (N = 3,952) completed a hand grip strength assessment and abbreviated Penn State Worry Questionnaire (PSWQ) and were divided into sex-specific tertiles based on strength. A score of ≥23 on the PSWQ defined caseness of GAD. At two-year follow-up, GAD was assessed with the Composite International Diagnostic Interview—Short Form. Results: Prevalence and incidence of GAD were 18.2% (N = 718) and 0.9% (N = 29), respectively. Adjusting for age, sex, waist circumference, social class, smoking status, and physical activity, a one-standard-deviation (1-SD) increase in strength was associated (OR, 95%CI) with 12.1% (OR = 0.88, 0.80–0.96; p < 0.01) lower odds of prevalent GAD, and middle and high strength tertiles were associated with 27.3% (OR = 0.73, 0.59–0.89; p < 0.01) and 23.1% (OR = 0.77, 0.62–0.95; p < 0.05) lower odds, respectively. A 1-SD increase in strength was non-significantly associated with 24.2% (OR = 0.76, 0.50–1.14) lower odds of incident GAD, and middle and high strength tertiles were non-significantly associated with 31.4% (OR = 0.69, 0.30–1.58) and 66.5% (OR = 0.34, 0.11–1.00) lower odds, respectively (all p > 0.05). There was no significant interaction between strength tertiles and sex. Limitations: The observational nature of the study limits inferring causality. Conclusions: Increased hand grip strength may be associated with lower odds of developing GAD in older adults. Larger investigations of prospective associations are needed.