Associations between relative grip strength and type 2 diabetes mellitus: The Yangpyeong cohort of the Korean genome and epidemiology study.

Objective: To investigate the association between relative grip strength and the prevalence of type 2 diabetes mellitus (T2DM) independently and in combination with body mass index (BMI) in Korean adults.

Methods: The cross-sectional study includes 2,811 men and women (age 40 to 92 years old) with no history of heart disease, stroke, or cancer. Relative grip strength was measured by a handheld dynamometer and calculated by dividing absolute grip strength by body weight. Logistic regression analysis was used to calculate the odds ratios (ORs) and 95% confidence intervals (CIs) of T2DM by sex-specific quintiles of relative grip strength. In a joint analysis, participants were classified into 4 groups: "weak (lowest 20% quintile one) and normal weight (BMI <25.0 kg/m2)", "weak and overweight/obese (BMI ≥25.0 kg/m2)", "strong (upper 80% four quintiles) and normal weight" or "strong and overweight/obese".

Results: Among the 2,811 participants, 371 were identified as having T2DM. Compared with the lowest quintile of relative grip strength (weakest), the ORs (95% CIs) of T2DM were 0.73 (0.53-1.02), 0.68 (0.48-0.97), 0.72 (0.50-1.03), and 0.48 (0.32-0.74) in upper quintiles two, three, four, and five, respectively, after adjusting for BMI and other potential confounders. In the joint analysis, compared with the "weak and overweight/obese" reference group, the odds of T2DM [ORs (95% CIs)] was lower in the "strong and overweight/obese" group [0.65 (0.46-0.92)] and the "strong and normal weight" group [0.49 (0.35-0.67)], after adjusting for potential confounders.

Conclusion: In this cross-sectional study, greater relative grip strength was associated with a lower prevalence of T2DM independent of BMI in Korean adults. Additional prospective studies are needed to determine whether a causal association exists between relative grip strength and T2DM prevalence considering BMI.