[Bone mineral loss in patients with chronic obstructive pulmonary disease]

Body weight loss is often observed in patients with chronic obstructive pulmonary disease (COPD). Bone mineral loss has also been reported in COPD, but the mechanisms are not well determined. To elucidate what factors influence on bone mineral content in COPD patients, we measured bone mineral content (BMC) by dual energy X-ray absorptiometry (DXA) (XR-26, Norland), pulmonary function, and ten minute walk distance (TMD) in Japanese elderly male patients with COPD. The subjects were 21 male patients with COPD (72.6 +/- 9.5 years) and 18 age-matched male normal individuals (66.5 +/- 9.5 years). COPD patients showed significantly (p < 0.05) lower BMC (1.82 +/- 0.33, 2.27 +/- 0.35 kg, respectively) compared with age-matched controls. BMC was significantly correlated with body weight and TMD (r = 0.71, r = 0.51, respectively). These results demonstrate that lower body weight and decreased exercise capacity account for the significantly lower bone mineral content of our COPD patients and that COPD patients with body weight loss may be at high risk for osteoporotic fracture.