Study of microalbuminuria in chronic obstructive pulmonary disease patients at tertiary care teaching hospital

BACKGROUND: Hypoxemia-induced endothelial dysfunction leads to microalbuminuria. Microalbuminuria (MAB) has also been used as a parameter to assess the risk of cardiovascular events in an individual. The aim of this study was to observe the relationship of MAB in patients with chronic obstructive pulmonary disease (COPD) and to correlate MAB with different stages of COPD. MATERIALS AND METHODS: This cross sectional study included 140 patients with COPD selected according to GOLD guidelines based on COPD test assessment score and the number of exacerbations who had smoking pack years of more than 10 years. Urine albumin creatinine ratio (UACR) more than 30 mg/gm represents MAB. RESULTS: The UACR increases as the severity of groups of COPD increases with significant differences in UACR values among different COPD groups. Significant differences were seen among various groups of COPD when compared for different clinical parameters such as SPO2, PaO2, PaCO2, pH, and C-reactive protein (CRP). Pearson correlation analysis revealed that UACR was significantly inversely related with PaO2 (r = -0.514, P < 0.001), SPO2 (r = –0.397, P < 0.001) and FEV1 (r = –0.441, P < 0.001) and it was significantly positively correlated with PaCO2 (r = 0.675, P < 0.001). CONCLUSION: This study indicates that there is strong relationship of MAB in patients with COPD and the levels of MAB increase as the severity of COPD increases due to hypoxia and endothelial dysfunction. As MAB is a marker for cardiovascular risk, patients with COPD can be routinely evaluated for the urine test of MAB specially who are at increased risk for cardiovascular events.