Evaluation of the association between thyroid-stimulating hormone with handgrip strength and dynapenia in euthyroid postmenopausal women

Objective To examine the association between serum thyroid-stimulating hormone (TSH) levels with handgrip strength (HGS) and dynapenia in euthyroid postmenopausal women. Methods This was an exploratory cross-sectional study among 385 participants from the Department of Obstetrics, Gynecology, and Reproduction of the Dexeus Women's University Hospital, Barcelona, Spain. Age, age at menopause, adiposity, alcohol consumption, body mass index (BMI), and smoking status were recorded. TSH was determined by electrochemiluminescence immunoassay. HGS was measured using a digital dynamometer, and physical activity was assessed by the International Physical Activity Questionnaire. Dynapenia was considered when HGS was <20 kg. A directed acyclic graph was designed to identify confounding variables. Multivariable linear and logistic regression models were adjusted by age, age at menopause, adiposity, BMI, glomerular filtration rate, glycated hemoglobin, physical activity, and smoking status. Results Multivariable linear regression model showed that age (beta = -0.22; 95% CI, -0.28 to -0.16), adiposity (beta = -0.15; 95% CI, -0.22 to -0.07), BMI (beta = 0.15; 95% CI, 0.04-0.25), glomerular filtration rate (beta = -0.04; 95% CI, -0.07 to -0.01), and physical activity (beta = 0.79; 95% CI, 0.07-1.5) were significantly associated with HGS. Instead, serum TSH levels were not significantly associated (beta = 0.21; 95% CI, -0.10 to 0.51). Multivariable logistic regression model showed that dynapenia was associated with age (OR, 1.20; 95% CI, 1.12-1.31) and glomerular filtration rate (OR, 1.03; 95% CI, 1.00-1.05). No significant association between TSH and dynapenia was observed (OR, 0.98; 95% CI, 0.78-1.23). Conclusions In this study of postmenopausal women, normal TSH levels were not associated with low HGS or dynapenia.