Anthropometric and body composition determinants of metabolically healthy and unhealthy overweight/obesity: an analysis among Malaysian healthcare workers

Metabolic health status varies among individuals with overweight and obesity, resulting in metabolically healthy and metabolically unhealthy phenotypes with differing cardiometabolic risk profiles. Asians develop obesity-related diseases at lower BMI thresholds. Healthcare workers have higher rates of obesity compared to the general population. This study examined associations of anthropometric and body composition measures with metabolic health status among a cohort of apparently-healthy Malaysian healthcare workers with overweight/obesity. Participants were recruited via voluntary convenience sampling among employees in an urban Malaysian academic medical centre. Individuals with BMI ≥ 23 kg/m² and no known cardiometabolic diseases were eligible. Data collected included anthropometric indices [neck circumference (NC), waist circumference (WC) and hip circumference (HC)], bioimpedance metrics [fat mass (FM), fat-free mass (FFM)] and biochemical analysis for glucose and lipids. Blood pressure, glucose and lipid levels were collected to unveil metabolic status. Metabolically healthy overweight/obesity (MHOO) was defined as absence of any metabolic abnormality (dysglycemia, elevated blood pressure or dyslipidemia), and otherwise as metabolically unhealthy overweight/obesity (MUOO). Correlation, multivariable logistic regression, and exploratory parallel mediation analyses were performed. Among 297 people with BMI ≥ 23 kg/m 2 , 100 (33.67%) were MHOO. Proportion of MUOO increased with higher BMI thresholds, with 85.32% being metabolically unhealthy at BMI ≥ 30 kg/m 2 . Elevated blood pressure is the predominant metabolic abnormality. MUOO individuals had higher FM and FFM. BMI, WC, HC and waist-to-height ratio correlated strongly with FM ( ρ = 0.75–0.93). NC and waist-to-hip ratio correlated better with FFM ( ρ = 0.68 and 0.41), and NC moderately correlated with triglyceride–glucose index (TyGI) ( ρ = 0.44). Adjusted for sociodemographic, body composition and other anthropometrics, NC remains modestly associated with MUOO (adjusted odds ratio 1.15; 95% CI 1.01–1.32). Inclusion of TyGI attenuated NC association with MUOO. Exploratory mediation analyses suggested both fat and lean mass expansions mediate metabolic risk, but a predilection for upper body expansion of FFM may be linked with MUOO. Metabolic disturbance is common among apparently-healthy people with raised BMI. High NC shows modest but consistent associations with metabolic risk, potentially reflecting upper-body fat-free mass expansion and insulin resistance; these exploratory findings warrant confirmation in larger cohorts. Not applicable.