Associations of sarcopenic obesity with the metabolic syndrome and insulin resistance over five years in older men: The Concord Health and Ageing in Men Project

Purpose: Previous cross-sectional studies investigating associations of sarcopenic obesity with metabolic syndrome (MetS) and insulin resistance have not utilised consensus definitions of sarcopenia. We aimed to determine associations of sarcopenic obesity with MetS and insulin resistance over five years in community-dwelling older men. Methods: 1231 men aged ≥70 years had appendicular lean mass (ALM) and body fat percentage assessed by dual-energy X-ray absorptiometry and hand grip strength and gait speed tests. Sarcopenia was defined as low ALM/height (m²) and low hand grip strength or gait speed (European Working Group definition); obesity was defined as body fat percentage ≥30%. MetS was assessed at baseline and 5-years later. Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) was assessed at 5-years only. Results: Men with sarcopenic obesity (odds ratio, 95% CI: 2.07, 1.21–3.55) and non-sarcopenic obesity (4.19, 3.16–5.57) had higher MetS likelihood than those with non-sarcopenic non-obesity at baseline. Higher gait speed predicted lower odds for prevalent MetS (0.45, 0.21–0.96 per m/s). Higher body fat predicted increased odds for prevalent and incident MetS (1.14, 1.11–1.17 and 1.11, 1.02–1.20 per kg, respectively) and deleterious 5-year changes in MetS fasting glucose, high-density lipoprotein cholesterol and triglycerides (all P < 0.05). Compared with non-sarcopenic non-obesity, estimated marginal means for HOMA-IR at 5-years were higher in non-sarcopenic obesity only (1.0, 0.8–1.1 vs 1.3, 1.2–1.5; P < 0.001). Similar results were observed when sarcopenic obesity was defined by waist circumference. Conclusions: Sarcopenic obesity does not appear to confer greater risk for incident MetS or insulin resistance than obesity alone in community-dwelling older men.