Should COPD patients be routinely evaluated for bone mineral density?

There are many factors that increase the risk of osteoporosis, including smoking, malnutrition, vitamin D deficiency, hypogonadism, limited physical activity due to chronic disease, and corticosteroid therapy in chronic obstructive pulmonary disease (COPD). The aim of this study was to investigate bone mineral density (BMD) in COPD outpatients receiving regular therapy in order to clarify whether they were suitable candidates for bone mass screening. Twenty-eight male, clinically stable COPD patients (mean age, 63 +/- 9 years) and 20 male volunteer subjects with normal pulmonary function, as a control group (mean age, 63 +/- 5 years) were admitted to the study. The BMD of the COPD patients and control subjects was measured by dual X-ray absorptiometry (Hologic QDR-4000). Pulmonary function tests and arterial blood gas analyses of COPD patients revealed moderate-degree airway obstruction with mild hypoxemia and normal pH. Rates of 42% and 67% for lumbar and femoral osteopenia, respectively, and 35%, and 10% for lumbar and femoral osteoporosis, respectively, were detected in the COPD patients; whereas the rates of lumbar and femoral osteopenia were 40% and 50%, respectively, and the rates of lumbar and femoral osteoporosis were 40% and 15%, respectively, in the control subjects. There was no statistically significant difference between the BMD values of the COPD and control groups. Lumbar BMD was 0.871 g/cm(2) in the COPD patients and 0.853 g/cm(2) in the control group (P = 0.682); femoral BMD was 0.790 g/cm(2) in the COPD patients and 0.795 g/cm(2) in the control group (P = 0.909). Bone density was correlated with the degree of airway obstruction and arterial blood pH. In conclusion, the BMD values of COPD patients were not different from those of control subjects of the same age group. We conclude that the risk of osteoporosis is not increased in appropriately treated patients with moderate-degree COPD, and there is no indication for bone mass screening in this group.