Chronic obstructive pulmonary disease is associated with osteoporosis and low levels of vitamin D

Abstract

We did a cross-sectional analysis of chronic pulmonary obstructive disease (COPD) patients without chronic use of systemic glucocorticoids (CUG). Osteoporosis was found in 51% and bone mineral density (BMD) was correlated with severity of disease. Low levels of vitamin D were found in 94%. All COPD patients may benefit from vitamin D supplementation and screening for low BMD. Patients with chronic pulmonary obstructive disease have low bone mineral density, caused by chronic use of systemic glucocorticoids and hypovitaminosis D. However, patients without CUG may also have low BMD. We performed a cross-sectional analysis in 49 patients (21 men, 28 postmenopausal women), with COPD without CUG, from Brazil (25 degrees 25' S). Several markers of bone metabolism were measured, plus BMD. Osteoporosis risk factors and history of fractures were investigated. Respiratory function was assessed by venous gasometry, spirometry, and oximetry. BMD results were compared to those of 40 healthy non-smokers controls. COPD patients had lower BMD at all sites (p < 0.01). Osteoporosis was observed in 51%. BMD independently correlated with stage of disease (lumbar spine, R = 0.38, p = 0.01; total femur, R = 0.36, p = 0.01; femoral neck, R = 0.40, p < 0.01). Ninety-four percent had low levels of vitamin D (<30 ng/mL) and 67% had secondary hyperparathyroidism. Vitamin D was correlated with oxygen saturation (R = 0.36, p = 0.01), with lower levels in those with saturation <88% (p = 0.01). Patients with COPD without CUG have increased risk for osteoporosis. Such patients have hypovitaminosis D, which is correlated with the severity of disease. Screening for low BMD and vitamin D supplementation may be warranted to all COPD patients.