Effect of relative handgrip strength and back muscle strength on the incidence of hypertension: 18-year follow-up in a population-based cohort study.

Substantial evidence supports an association between physical exercises and hypertension. However, the role of muscle strength, such as hand grip strength (HGS) and back muscle strength (BMS), remains unclear in this relationship. This study investigated whether low BMS and HGS accelerated incident hypertension in a population-based prospective study. A total 3,038 non-hypertensive subjects aged 40-69 years were followed-up for 18 years. In the analysis, the relationships between absolute and relative-muscle strength (relative-body mass index (BMI), weight, weight2/3, and waist circumference (WC)), and incident hypertension were analyzed using the Cox proportional hazards model. In multivariate analysis, weak strength of below -1.5 SD BMI and WC relative-BMS (BMI-BMS and WC-BMS), except absolute BMS, weight-, and weight2/3 relative-BMS, was associated with higher risk of incident hypertension (HR = 1.264, P = 0.050 and HR = 1.405, P = 0.003, respectively). Relative-BMS quartiles, except absolute-BMS quartiles, showed a significant trend of increased risk of incident hypertension as BMS decreased (Trend P < 0.05). Weak HGS, based Asian Working Group for Sarcopenia (AWGS) and Korea National Health and Nutrition Examination Survey (KNHNES) criteria, was also associated with higher risk of incident hypertension (HR = 1.679, P = 0.002 and HR = 1.515, P = 0.004, respectively). Weak HGS below -1.5 SD was associated with higher risk of incident hypertension in absolute HGS, BMI-, and WC relative-HGS (HR = 1.476, P = 0.001, HR = 1.374, P = 0.008, and HR = 1.530, P < 0.001, respectively). Relative-HGS quartiles, except absolute HGS, showed similar significant trend (Trend P < 0.001). In this study, we found that the BMS and HGS were an independent risk factor for the incident hypertension.