African Americans and Men with Severe COPD Have a High Prevalence of Osteoporosis

Abstract

Osteoporosis is a non-pulmonary manifestation whose true prevalence is uncertain in severe chronic obstructive pulmonary disease (COPD). We describe the prevalence and risk factors for osteoporosis in a large, well characterized COPD cohort. Dual energy x-ray absorptiometry of the lumbar spine and hip, full pulmonary function testing, cardiopulmonary exercise test, 6 minute walk distance and demographics were performed in 179 non-selected COPD patients. Patients were 59 ± 7 years old, smoked 53 ± 32 pack years, FEV1 26% ± 9.8, and 45% were currently taking prednisone. Bone mineral density measurements were abnormal in 97%; 66% had dual energy X-ray absorptiometry defined osteoporosis, while 31% had osteopenia. The prevalence of osteoporosis in males versus females was 70% versus 62% (p = 0.33); both groups had similar fracture rates. The prevalence of osteoporosis in African Americans versus Caucasians was 69% versus 65% (p = 0.78). Caucasians had a significantly lower Ward's Triangle T score than African Americans (−2.52 ± −0.96 vs. −2.16 ± −0.91, p = 0.04). Those with bone fractures took higher doses of prednisone than those without fractures. Univariate analysis identified BMI and FVC% as predictors for osteoporosis (p = 0.03 OR 0.934 p = 0.006 OR 0.974). Multivariate analysis revealed only FVC% as a significant predictor (p = 0.006, OR 0.974). Osteoporosis is highly prevalent in severe COPD, and affects males and African Americans to a similar degree as females and Whites. Osteoporosis should be considered in severe COPD regardless of race or gender.