The association between sarcopenic obesity and depression in middle-aged and elderly U.S. adults: insights from the NHANES study

Purpose: This study aimed to explore the association between sarcopenia, obesity, and sarcopenic obesity with depression in a middle-aged and elderly population in the United States. Methods: We analyzed data from the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2006 and from 2011 to 2018, including 5155 participants aged 45 years and older. Obesity was defined by a body mass index (BMI) ≥ 30 or waist circumference (WC) ≥ 102 cm in men or ≥ 88 cm in women. Sarcopenia was assessed using dual-energy X-ray absorptiometry (DXA) to calculate appendicular skeletal muscle mass index (ASMI), with gender-specific cut-offs. Multivariate logistic regression models adjusted for various covariates were used to assess the associations. Results: Participants classified into the sarcopenia-only, obesity-only, and sarcopenic obesity groups exhibited multivariable-adjusted odds ratios (ORs) for depression of 1.35 (95% CI 0.60–2.18; P = 0.371), 1.37 (95% CI 1.03–1.82; P = 0.031), and 2.07 (95% CI 1.36–3.16; P < 0.001), respectively, compared to the robust group. Sensitivity analyses using alternative definitions of obesity and multiple imputation for missing data confirmed these findings. Subgroup analyses revealed that the association between sarcopenic obesity and depression was more pronounced in middle-aged women (aged ≤ 52 years). Conclusion: This study underscores the significant relationship between sarcopenic obesity and depression in a large U.S. middle-aged and elderly population. Interventions focusing on weight control and muscle mass enhancement through proper nutrition and physical activity may reduce depression incidence, thereby promoting healthy aging. © The Author(s) 2025.