Metabolically healthy obese women and functional capacity

Obesity and the metabolic syndrome are significant determinants of functional capacity in women. In the past decade, the term "metabolically healthy obese" (MHO) emerged in the literature to identify a distinct category of obese individuals presenting less metabolic impairment than expected. However, MHO women might have similar risk than non-MHO women for nonmetabolic weight-related co-morbidities, including altered functional capacity.

Eighty six obese women aged from 28 to 74 years old were studied. MHO was defined as a body mass index (BMI) ≥30.0 kg/m(2) with less than one metabolic syndrome criteria based on the Adult Treatment Panel III (ATP III) definition. Walking distance (m) and walking speed (m/sec), evaluated by the 6-min walk test, were used as indicators of functional capacity.

Twenty one percent of the sample was considered MHO. Age, BMI, physical activity level, and diastolic blood pressure were not significantly different between MHO and non-MHO women. MHO women performed better on the 6-min walk test (519.8 m±68.2 vs. 448.4 m±67.1; P≤0.01) compared to non-MHO women. Moreover, in multiple regression analyses, MHO status and BMI were significantly associated with walking speed after adjustment for age, physical activity level, the total number of chronic conditions, and arthritis/osteoarthritis.

Our results show that MHO women have a better functional capacity than non-MHO women, and therefore could be at lower risk for future disability. However, weight management remains important because BMI was also an independent predictor of functional capacity regardless of metabolic profile.