Abstract
Sarcopenia, characterized by the progressive loss of skeletal muscle mass and strength, significantly impacts the people, leading to increased frailty and mortality. The atherogenic index of plasma (AIP), a biomarker for lipid imbalance, may be linked to sarcopenia due to shared pathways of inflammation and metabolic dysregulation. Data from the National Health and Nutrition Examination Survey (NHANES) 2011-2018 cycles were analyzed. The AIP was calculated as the logarithm of the ratio of triglycerides to High density lipoprotein cholesterol. Sarcopenia was defined using the appendicular skeletal muscle mass index (ASMBMI) adjusted for body mass index (BMI). Multivariable linear regression and logistic regression models were employed to assess the association between AIP and ASMBMI, as well as sarcopenia. Restrictive cubic spline curves were utilized to analyze potential nonlinear associations between AIP and outcome indicators. Additionally, subgroup analyses and intergroup interaction tests were performed. Elevated AIP levels were associated with decreased ASMBMI and an increased risk of sarcopenia. After adjusting for confounding factors, the association between AIP and ASMBMI remained significant (Beta [95% CI] = -0.02 [-0.03, -0.01], P < 0.001). AIP was significantly associated with sarcopenia (OR [95% CI] = 2.6 [1.78, 3.81], P = < 0.001). AIP is significantly associated with reduced muscle mass and potentially with sarcopenia, suggesting that lipid metabolism plays a critical role in muscle health. Identifying AIP as a modifiable risk factor could have important public health implications for managing sarcopenia.