Use of DEXA Scan in Chronic Obstructive Pulmonary Disease (COPD) and Comparative Analysis of Pulmonary Hypertension with GOLD classification Versus BODE Index in COPD

Abstract

Background: Osteoporosis, sarcopenia, pulmonary hypertension are common with COPD. There are only few studies which have evaluated the relationship of these co-morbidities with COPD severity. Aim: To study osteoporosis in terms of bone mineral density (BMD) and sarcopenia in terms of fat free mass index (FFMI) with dual energy x-ray absorptiometry (DEXA); and their relation with forced expiratory volume in one second (FEV₁%). To study relation of pulmonary hypertension (PH) with forced expiratory volume in 1 second (FEV1) and BODE index in COPD. Materials and Methods: In 30 stable COPD patients, BMD and FFMI were calculated with DEXA scan. Two groups of FEV₁ ?50% and FEV₁ 50% and three groups of BODE index 5, 5-6 and ?7 were compared with PH severity. Results: All patients had low BMD (33% osteopenia and 66% osteoporosis) and 83.3% had sarcopenia. Chi-square test to assess the significance of osteoporosis and sarcopenia in relation to FEV₁ groups was statistically insignificant (p value=0.88). 5/7 had normal pulmonary artery pressure (PAP) and 2 had mild PH in group I i.e. FEV₁ ?50%, whereas in group II i.e. FEV₁ 50 %, 2 had normal PAP; 15, 3 and 2 had mild, moderate and severe PH respectively. Binary logistic regression to assess PH in relation to FEV₁ and BODE index showed odds ratio for FEV₁ ? 50% statistically significant (p value= 0.016). Conclusion: Osteoporosis and sarcopenia are very common in COPD in Indian population but there is no correlation with FEV₁. Though BODE index is a good prognostic indicator, FEV₁ is more likely to correlate with severity of PH than BODE index.