Android shape independent of aerobic fitness: a risk factor for low bone mineral content in overweight and obese latina women.

Abstract

Objective: The link between central adiposity and osteopenia has not been extensively studied in Latina women. In particular, the association between abdominal weight and bone mineral content (BMC) and bone mineral density (BMD), independent of total weight and aerobic capacity, remains uncertain, especially in overweight and obese individuals.

Methods: Trunk weight, total body fat mass, fat-free mass, BMC, and BMD of 33 premenopausal Latina women age 22 to 51 years from Los Angeles, California were measured using dual-energy X-ray absorptiometry (DXA). Waist circumference (WC) was measured without clothing at the smallest circumference of the torso. Peak aerobic capacity (peak VO2) was determined by treadmill ergometry with direct measurement of oxygen consumption.

Results: Partial correlations controlling for total body fat mass, fat-free mass, and peak VO2 revealed a significant inverse relationship between BMC and WC (r = -0.54, P < 0.05) but not between BMD and WC (r = -0.18, P = 0.41). Similarly, while controlling for total body fat, fat-free mass, and peak VO2, BMC was inversely associated with trunk fat (r = -0.75, P < 0.001), with trunk lean (r = -0.61, P < 0.05) and with total trunk weight (r = -0.75, P < 0.001); results were non-significant for BMD. When these analyses were repeated separately in overweight (n = 10) versus in the obese (n = 18) women, inverse relationships between BMC and trunk fat as well as between BMC and total trunk weight became stronger in the obese compared with the overweight women.

Conclusion: Although general obesity may prevent osteoporosis, these findings suggest that abdominal obesity (ie, trunk weight) specifically and independently may adversely influence bone mass.