Association between lipid ratios and sarcopenia and the mediating roles of inflammatory biomarkers in a cross-sectional study from NHANES 2011–2018

Sarcopenia, which leads to reduced quality of life and increased medical burden, is challenging to diagnose in a timely manner. Lipid metabolism plays a role in sarcopenia, and this study explored the associations between blood lipid profile parameters and sarcopenia. Using data from the National Health and Nutrition Examination Survey 2011-2018, we conducted weighted multivariate logistic regression to investigate the associations between lipid ratios and sarcopenia, including non-high-density lipoprotein cholesterol (non-HDL-C) to HDL-C, triglyceride (TG) to HDL-C, low-density lipoprotein cholesterol (LDL-C) to HDL-C, and remnant cholesterol (RC) to HDL-C ratios. We performed subgroup analyses to assess interactions with other covariates and used mediation models to evaluate the mediating roles of inflammatory biomarkers. We included a total of 9500 non-sarcopenic and 849 sarcopenic participants aged 18-59 years. While we observed modest correlations between individual lipid components and sarcopenia, we obtained significant positive associations for lipid ratios. Specifically, non-HDL/HDL-C (OR = 1.09; 95% CI 1.03-1.15; P = 0.003), TG/HDL-C (OR = 1.02; 95% CI 1.02-1.04; P = 0.014), LDL/HDL-C (OR = 1.27; 95% CI 1.11-1.45; P < 0.001), and RC/HDL-C ratios (OR = 1.55; 95% CI 1.16-2.07; P = 0.004) showed strong associations with sarcopenia. These associations were more pronounced in younger participants, those with lower family economic status, and those without self-reported diabetes. Furthermore, there were significant mediation effects of inflammatory biomarkers on the association between non-HDL/HDL-C, LDL/HDL-C, and RC/HDL-C and sarcopenia risk, with proportions ranging from 2.90 to 6.36%. In conclusion, our study demonstrated the positive associations between lipid ratios and sarcopenia in middle-aged adults, suggesting the potential of these lipid ratios for improving sarcopenia case identification. Further research is required to explore the underlying mechanisms.