Mediation and Moderation of Adiposity Indicators for the Association Between Grip Strength and Cardiovascular Disease Risk Scores.

Background: This cross-sectional study evaluated mediation or moderation of adiposity indicators on the association between handgrip strength (HGS) and the 10-year cardiovascular disease risk scores (CVDR). Methods: In data of 15,206 Korean adults (6961 men and 8245 women) aged ≥30 years using the Korea National Health and Nutrition Examination Survey, HGS, body mass index (BMI), height, waist circumference, the components of Framingham CVDR, and covariates (sociodemographic factors, health behaviors, perceived stress, health, functional status, and nutritional status) were used. BMI, waist circumference, and waist-to-height ratio were used as adiposity indicators. Gender-specific general linear model and PROCESS Macro were applied. Results: HGS had an inverse association with the CVDR after adjusting for the covariates and BMI (or waist circumference), while adiposity indicators had positive associations with the CVDR after adjusting for the covariates and HGS. Mediation analysis shows indirect effects of adiposity indicators (0.010-0.019, P < 0.05) and direct effect of HGS on the CVDR (-0.08 to -0.09, P < 0.05) after adjusting for the covariates. Moderation analysis reveals positive interactions between HGS and adiposity indicators in the relationship with the CVDR after adjusting for the covariates (P < 0.05). The inverse association between the HGS and the CVDR tended to be stronger with decrease in adiposity levels. Conclusions: Adiposity indicators mediated and moderated the association between HGS and the CVDR in Koreans. The moderating effects indicate that the lower the levels of the adiposity indicators, the stronger the CVDR improvement effect of HGS.