“…Chronic use of systemic glucocorticoids was thought to be the major cause of bone loss. (14,15) However, osteoporosis and fractures also have been reported in patients who have never taken glucocorticoids. (4,5) Several other factors associated with the disease itself may contribute to bone loss in these patients, including release of inflammatory cytokines from the lungs into the circulation, hypercapnia, low body mass index (BMI), hypoxia, decreased fat-free mass, hypogonadism, vitamin D deficiency, poor nutrition, and immobility.…”