Bone mineral density in patients with chronic obstructive pulmonary disease who are candidates for lung transplant

INTRODUCTIóN: After cystic fibrosis, lung transplantation (LT) patients with prior chronic obstructive pulmonary disease (COPD) are most susceptible to loss of bone mineral density (BMD).

To determine the prevalence of BMD loss among COPD patients being evaluated as LT candidates, seeking to identify, their risk profile.

This cross-sectional study included COPD patients who were LT candidates evaluated from January 2007 to December 2009. To identify patients at risk of fracture, BMD at the femoral neck and lumbar spine was assessed by bone densitometry. For categorization, we followed the World Health Organization criteria. To evaluate the risk profile, we recorded data on age, sex, smoking, lung function forced expiratory volume in 1 second, distance covered in the 6-minute walk test, body mass index, and degree of dyspnea. We recorded individual data as well as grouped them the multidimensional BODE (Body mass index Obstruction Dyspnea Exercise capacity) index.

The study cohort consisted of 64 patients (51 men and 13 women). The overall prevalence of low BMD in any of the explored territories was 84.4%, affecting 88.2% of men and 69.2% of women. Osteoporosis was identified in 56.2% of patients, reaching a serious degree in 11/64 (17.2%). No significant differences were observed in any evaluated parameter when patients were separated into those with normal versus pathological BMD. When patients with osteopenia and osteoporosis were compared, we observed that the former showed a lower exercise capacity (P=.023) and a higher BODE index (P=.002).

The prevalence of a low BMD level was increased among male patients with a worse BODE index, especially due to a reduced exercise capacity.