VERONA, ITALY — Contrary to conventional wisdom, obese patients may not be protected against osteoporosis and could present with significant bone loss, new data show.
In a study of 233 morbidly obese patients, 34% showed a significant decrease in bone mineral density at the lumbar spine with a median T score of −1.98 (range −1.1 to −4.2), Dr. Carlo Lubrano and his colleagues reported in a poster at a joint meeting of the Italian Association of Clinical Endocrinologists and the American Association of Clinical Endocrinologists.
Low bone mass is defined as a bone density at the spine or hip between 1.0 and 2.4 standard deviations below the average for healthy young adults, which translates to a T score of −1 to −2.5, according to the World Health Organization. Bone density 2.5 standard deviations or more below the young adult mean is categorized as osteoporosis.
The 195 women and 38 men in the study had an average body mass index of 37 kg/m2 and a mean age of 44 years. Bone mineral density (BMD) was measured by dual-energy x-ray absorptiometry.
Overall, 31.5% of the women showed a median BMD of 0.971 g/cm
It had been thought that obesity might protect the skeleton against osteoporosis. Recent evidence suggests that obesity may actually weaken the skeleton and increase the risk of fractures. The authors concluded that a “specific and careful characterization of skeletal metabolism might be useful in both female and male obese subjects.”