Handgrip strength in patients with subclinical hypothyroidism or subclinical hyperthyroidism compared with that in...

This systematic review and meta-analysis assessed handgrip strength in patients with either subclinical hypothyroidism or subclinical hyperthyroidism as compared with euthyroid individuals.

We searched in Web of Science, Scopus, and PubMed databases for information about cross-sectional studies comparing subclinical hypothyroid or subclinical hyperthyroid patients and euthyroid control individuals. The quality of included studies was evaluated with the Newcastle-Ottawa Scale. Random-effect meta-analyses were conducted to minimize the effects of uncertainty associated with inter-study variability. Results are reported as mean differences, standardized mean differences, or odds ratios with 95 % confidence intervals. Heterogeneity between studies was assessed using I² and τ² statistics.

Seven studies with low or moderate risk of bias were eligible for inclusion in the meta-analysis of patients with either subclinical hypothyroidism or hyperthyroidism compared with euthyroid individuals. The meta-analysis of five studies of patients with subclinical hypothyroidism showed they had lower handgrip strength (standardized mean difference: -0.61, 95 % confidence interval -1.15, -0.07; p = 0.03) and lower thyroxine levels (standardized mean difference: -0.52, 95 % confidence interval -0.87, -0.16; p = 0.004) than euthyroid individuals. They also had a higher body mass index (mean difference: 1.05, 95 % confidence interval: 0.17, 1.93, p = 0.02), higher total cholesterol (standardized mean difference 0.28, 95 % confidence interval 0.09, 0.46, p = 0.003) and lower thyroxine levels (standardized mean difference: -0.52, 95 % confidence interval -0.87, -0.16; p = 0.004), and a higher risk of sarcopenia (odds ratio: 2.12, 95 % confidence interval 1.40, 3.22, p = 0.0004) than euthyroid individuals. The meta-analyses of four studies of patients with subclinical hyperthyroidism did not show differences in measured outcomes compared with euthyroid individuals.

Patients with subclinical hypothyroidism have lower handgrip strength than euthyroid individuals. There was no significant difference in handgrip strength between patients with subclinical hyperthyroidism and euthyroid individuals. PROSPERO registration: CRD420251004586.