Risk Factors For Osteoporosis In Patients With Chronic Obstructive Pulmonary Disease

【Objective】To study the risk factors of osteoporosis (OP) and the relationship betwee -n osteoporosis and pulmonary function in patients with chronic obsturctive pulmonary dise -ase (COPD).【Methods】One hundred and eighty patients (82 females and 98 males) with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) from March 2006 to June 2008 were enrolled in this study. The bone mineral density (BMD) of lumbar vertebrae and hip joint were tested by dual energy X-ray absorptiometry (DEXA). All the patients were divided into two groups with or without osteoporosis.The smoking history, incidence of fractures, and glucocorticosteroid using history were recorded. The pulmonary function, 6-minute walk distance ( 6-MWD), body mass index (BMI) and blood gas analysis were evaluated. 66 healthy subjects (24 males and 42 females ) were reruited as control group, age varies from 65-79 years old, mean age 70±4 years.【Results】The mean age of all patients was 72±7 years, and the mean smoking amount was 59±27 pack years. 180 patients finished these examination: pulmonary function test, BMD examination, blood gas analysis. 60 patients finished the 6-MWD examination. 30% of the patients had inhaled or take oral glucocorticoids for more than 3 months. The BMD measurement results showed that 95% patients were lower than the normal level, and 119 patients had (66%) osteoporosis, 61 males and 58 famles (62%υs70%, x2=1.435, p =0.33), and 52 patients had (29%) osteopenia. 7 healthy males (29%) and 15 females (35.7%) were diagnosed as OP in the control group.Linear correlation analysis showed that BMI, 6MWD, RV% , FVC% , PO2 had positiv -e correlation with osteoporosis (r=0.362, 0.635, 0.688, 0.973, 0.637; p <0.05)【Conclusions】 Osteoporosis is one of the extrapulmonary effects in elder COPD patients. The inciden -ce of osteoporosis in COPD is much higher than that in healthy people. The prevalence of osteoporosis is high in elderly patients with moderate or severe COPD. Enough attention and active intervention should be paid.Lower BMI, limited physical activity, increased RV% and decreased FVC%, Hypoxia may be the risk factors which lead to osteoporosis in COPD.