Association between lipid accumulation products and relative handgrip strength: a large population-based study

Given the increasing prevalence of chronic diseases in the aging population, it is of great importance to gain an understanding of how changes in body composition affect health outcomes. Handgrip strength (HGS) serves as a valuable proxy for overall muscle strength, while relative HGS (RHGS) adjusts for body size, providing a more accurate assessment of the relationship between muscle strength and metabolic disease. Lipid accumulation products (LAP) are an indicator that can reflect visceral lipid accumulation. Based on previous studies, the relationship between LAP and RHGS has not been explored. This study aims to address this gap in the literature and provide insights for public health recommendations. Data was collected and extracted from the 2011-2014 National Health and Nutrition Examination Survey (NHANES) database. LAP was calculated from the arithmetic product of waist circumference (WC) and fasting plasma triglyceride (TG), the calculation as following formulas: for females, [WC (cm) - 58] × [TG (mmol/l)], and for males, [WC (cm) - 65] × [TG (mmol/l)]; RHGS was derived from the HGS to BMI ratio. The correlation between the variables was initially explored using multivariate linear regression. Secondly, smoothed-fitted curves were used to investigate the non-linear relationship between the variables. The inflection point values were determined based on the results of the threshold effect analysis. Subgroup analyses were also conducted to assess the stability of the relationship between the variables in different populations. The study analyzed 3990 patients. After accounting for different covariates, multivariate linear regression analysis demonstrated a significant negative correlation between increased levels of LAP and increased levels of RHGS (beta coefficient = -0.0020; 95% confidence interval CI: -0.0023 to -0.0017; P < 0.0001). The interaction test did not have a statistically significant effect on this association. Furthermore, curve fit and threshold effect analysis demonstrated a non-linear relationship with a breakpoint at 49.8083 cm·mmol/L. The results of this study demonstrate an inverse relationship between LAP and RHGS in various populations in the United States. These findings provide compelling evidence of the clinical significance of LAP as a predictor of RHGS, offering valuable insights for developing early intervention strategies in high-risk populations.