Association Between Sex-specific Handgrip Strength and Plasma Glycated Hemoglobin Levels Among Older Adults: A...

Adults with diabetes have 37% to 109% higher odds of sarcopenia than normoglycemic individuals. Handgrip strength (HGS) is a key marker of sarcopenia, yet its association with glycated hemoglobin (A1C), a measure of long-term glycemia, remains unclear.

We conducted a cross-sectional study of 121 outpatients ≥65 years of age (80 women, 41 men). HGS was measured 3 times per hand using a calibrated dynamometer and the mean was recorded. Low HGS was defined using cutoffs of the European Working Group on Sarcopenia in Older People. Fasting A1C, analyzed in an accredited laboratory, was categorized as normal (<5.7%), prediabetes (5.7% to 6.4%), and diabetes (≥6.5%). Correlations between A1C and anthropometric/functional measures were evaluated, and multivariate linear regression identified A1C predictors.

The mean HGS was 26 kg in women and 39 kg in men; 11 participants (9.5%) had low HGS. Prediabetes prevalence was 49% in women and 41% in men. A1C correlated inversely with HGS in men (r=-0.47, p=0.002), but not in women (r=-0.16, p=0.14). Trend analysis showed decreasing grip strength and gait speed across A1C categories in men (p_trend=0.0015 and 0.012, respectively), but not in women. Post hoc power analysis showed that the smaller correlation between HGS and A1C in women had low statistical power, suggesting that the nonsignificant result may be due to insufficient power rather than a true absence of association.

Lower HGS was associated with higher A1C in older men. The nonsignificant results in women are likely attributable to low statistical power.