Associations between socioeconomic status and obesity, sarcopenia, and sarcopenic obesity in community-dwelling older adults: The Tasmanian Older Adult Cohort Study.

Background: Social disadvantage may contribute to increased prevalence of sarcopenia and obesity. This study investigated if socioeconomic factors are associated with obesity, sarcopenia, or sarcopenic obesity (SO), in community-dwelling older adults.

Methods: This was a cross-sectional analysis of data from the Tasmanian Older Adult Cohort study. Obesity was defined by body fat percentage (Men: ≥25%; Women: ≥35%) and sarcopenia was defined as the lowest 20% of sex-specific appendicular lean mass (ALM)/height (m) and handgrip strength. Socioeconomic factors investigated were education (tertiary degree, secondary or no secondary school), occupation (high skilled white-collar, low skilled white-collar, or blue-collar) and residential area (advantaged or disadvantaged area). Multinomial logistic regression analyses yielding odds ratios (95% confidence intervals) were performed and adjusted for potential confounders. Mediation analysis was performed.

Results: 1099 older adults (63.0 ± 7.5 years; 51.1% women) participated. Older adults with a tertiary degree were significantly less likely to have obesity (0.68; 0.47, 0.98) and SO (0.48; 0.24, 0.94) compared with those who had no secondary schooling. No associations were found for occupation. Similarly, older adults living in advantaged areas were significantly less likely to have obesity (0.61; 0.39, 0.95). Steps per day mediated the association between residential area and body fat percentage by 51%.

Conclusion: Lower educational attainment, but not occupation, was associated with increased likelihood for both obesity and SO in community-dwelling older adults. Low physical activity levels in disadvantaged areas substantially contributed to higher obesity prevalence in this population. Further research is necessary to confirm whether similar associations exist in populations with greater levels of social disadvantage and to design effective community-based interventions.