Three-year weight change and cardiometabolic risk factors in obese and normal weight adults who are metabolically healthy: the atherosclerosis risk in communities study

BACKGROUND/OBJECTIVES: Approximately 17% of obese Americans are free of the cardiometabolic risk factors, but few studies have compared responses to weight change in metabolically healthy obese (MHO) and metabolically healthy normal weight (MHNW) adults. We compared the impact of weight loss, weight maintenance and weight gain on cardiometabolic risk factors in the MHO and the MHNW. SUBJECTS/METHODS: Data were from the Atherosclerosis Risk in Communities (ARIC) study. Multiple observations on 2710 participants were included, yielding 4541 observations of sequential 3-year intervals. Metabolically healthy was defined as absence of all components of metabolic syndrome excluding waist circumference. Mixed effects models were used to compare changes in each of five cardiometabolic risk factors within weight change categories (<-3% for weight loss, +/- 3% for weight maintenance and >3% for weight gain). RESULTS: Weight loss was associated with comparable small changes or no changes in cardiometabolic risk factors in MHO and MHNW individuals. Weight gain was associated with larger increases in systolic (8.6 vs 6.2 mm Hg) and diastolic (3.9 vs 2.5 mm Hg) blood pressure, triglycerides (21.9 vs 15.8 mg/dl) and glucose (4.9 vs 1.9 mg/dl) in MHO individuals compared with MHNW individuals. Weight maintenance was associated with larger increases in triglycerides (10.0 vs 6.4 mg/dl) and glucose (1.7 vs 0.9 mg/dl) in MHO compared with MHNW individuals. MHO weight losers had more favorable changes in the five cardiometabolic risk factors compared to MHO weight maintainers (P<0.02) or gainers (P<0.0001). CONCLUSIONS: This work showed differences between MHNW and MHO adults and supports recommendations for weight loss in the MHO in order to avoid increases in risk factors associated with weight maintenance and weight gain.