Does normal weight obesity increase the risk of cardiometabolic dysregulation and cardiovascular mortality in adults with normal BMI?
Normal weight obesity is associated with a significantly higher prevalence of metabolic syndrome and, in women, an increased risk of cardiovascular mortality, highlighting the limitation of BMI alone for cardiovascular risk assessment.
AIMS: We hypothesized that subjects with a normal body mass index (BMI), but high body fat (BF) content normal weight obesity (NWO), have a higher prevalence of cardiometabolic dysregulation and are at higher risk for cardiovascular (CV) mortality. METHODS AND RESULTS: We analysed 6171 subjects >20 years of age from the Third National Health and Nutrition Examination Survey (NHANES III) and the NHANES III mortality study, whose BMI was within the normal range (18.5-24.9 kg/m(2)), and who underwent a complete evaluation that included body composition assessment, blood measurements, and assessment of CV risk factors. Survival information was available for >99% of the subjects after a median follow-up of 8.8 years. We divided our sample using sex-specific tertiles of BF%. The highest tertile of BF (>23.1% in men and >33.3% in women) was labelled as NWO. When compared with the low BF group, the prevalence of metabolic syndrome in subjects with NWO was four-fold higher (16.6 vs. 4.8%, P < 0.0001). Subjects with NWO also had higher prevalence of dyslipidaemia, hypertension (men), and CV disease (women). After adjustment, women with NWO showed a significant 2.2-fold increased risk for CV mortality (HR = 2.2; 95% CI, 1.03-4.67) in comparison to the low BF group. CONCLUSION: Normal weight obesity, defined as the combination of normal BMI and high BF content, is associated with a high prevalence of cardiometabolic dysregulation, metabolic syndrome, and CV risk factors. In women, NWO is independently associated with increased risk for CV mortality.
“Using the term 'normal weight obesity' is really a way of being more precise about the changing conceptualization of obesity, because the real definition of obesity is excess body fat. Our study demonstrates that even people with normal weight may have excessive body fat, and that these people are at risk for metabolic abnormalities that lead to diabetes and, eventually, to heart disease.”
Romero‐Corral et al. (Fri,) studied this question.