Association between social determinants of health and sarcopenia: A cross-sectional study

Background Social factors significantly influence health. Existing studies indicate that lower socioeconomic status and malnutrition are risk factors for sarcopenia. Nevertheless, the connection between multiple social determinants of health (SDoH) and sarcopenia has not been thoroughly investigated. Methods We analyzed four survey cycles from the cohort of adults aged 20 years and above in the 2011–2018 National Health and Nutrition Examination Survey. The domains of SDoH include employment; poverty income ratio; food security; education; health insurance coverage; health insurance type; housing conditions; and marital status. Sarcopenia was defined as appendicular skeletal muscle mass (ASM) standardized by the body mass index (ASM/BMI). Weighted multivariable logistic regression models were employed to investigate the associations between SDoH and sarcopenia. Restricted cubic splines (RCS) was employed to explore the potential non-linear association between SDoH and sarcopenia, while subgroup analyses and interaction tests were used to assess model robustness. Results The study incorporated 8,270 adult participants, whose average age was 40 ± 12 years. The sample comprised 50.0% males and 50.0% females, a weighted prevalence of sarcopenia of 7.1%. Fully adjusted logistic regression models indicated that each one-unit increase in SDoH was associated with a significant 25% increase in sarcopenia risk (OR = 1.25, 95% CI: 1.19–1.32, P < 0.001).RCS curves revealed a dose-response relationship between SDoH and sarcopenia. After full adjustment for confounding factors, employment status, housing condition, and marital status were positively associated with the risk of sarcopenia (p < 0.05). Subgroup analyses indicated that the impact of SDoH was attenuated among smokers and individuals with diabetes (interaction P-values = 0.048 and 0.037, respectively). Conclusion The cumulative burden of adverse SDoH among U.S. adults is significantly associated with an increased risk of sarcopenia, with key modifiable factors including financial hardship, housing instability, and single status. The findings indicate that sarcopenia is not merely a biomedical issue but is profoundly shaped by social environments. To address sarcopenia and promote healthy aging, comprehensive public policies aimed at mitigating adverse social factors are urgently needed.