Osteoporosis in chronic obstructive pulmonary disease patients.
PURPOSE OF REVIEW
The purpose of this review is to examine the state of knowledge and clinical practice in the association of chronic obstructive pulmonary disease to osteoporosis and fracture incidence.


RECENT FINDINGS
There is a clear association between chronic obstructive pulmonary disease and excessive bone loss/risk of fractures. Little is known about the pathophysiological processes involved in the bone loss, but recent reports point to a continuous systemic inflammatory state in patients with chronic obstructive pulmonary disease. This inflammation involves the release of inflammatory cytokines such as tumour necrosis factor-alpha and interleukin-1. During the course of chronic obstructive pulmonary disease, a protein catabolic process takes place, including increased production of catalytic enzymes (matrix metalloproteinases etc.), which together with the inflammatory cytokines induces bone resorption.


SUMMARY
Patients with chronic obstructive pulmonary disease are at increased risk of osteoporosis and fractures. Risk factors such as smoking, advanced age, physical inactivity, malnutrition, and low weight may be responsible, but a number of pathophysiological explanations including the presence of a chronic inflammatory state with increased levels of proinflammatory cytokines and protein catalytic enzymes may also be involved. The use of oral glucocorticoids is also a significant risk factor. Increased awareness is highly warranted to diagnose osteoporosis at an early stage, and professionals should be aware of the risk of osteoporosis in this patient population.