Microalbuminuria in patients with chronic obstructive pulmonary diseases attending pulmonology clinic at Muhimbili National Hospital, Dar Es Salaam, Tanzania

Abstract

Background: Extra pulmonary co morbidities particularly cardiovascular diseases (CVD) are common and significant in chronic obstructive pulmonary disease (COPD). Extra pulmonary involvement often contributes to exacerbations, frequent hospital admissions and high mortality. COPD patients do die more due to extra-pulmonary than COPD itself. Microalbuminuria gives an important evidence of endothelial dysfunction in COPD patients. Using microalbuminuria, early detection and therefore appropriate management of the subclinical extra pulmonary involvement in COPD patients will help in reducing morbidity and mortality. Objective: To determine the prevalence of microalbuminuria and severity correlates in COPD patients attending the MNH pulmonology clinic, Dar es Salaam Tanzania Methodology: A cross-sectional descriptive study was conducted from July 2016 to December 2016. Study participants were consecutively recruited from the MNH Pulmonology Clinic. A structured questionnaire was used to collect social demographic factors and clinical parameters from the study participants. Lung functions were assessed by means of the Easy One™ spirometer. Post bronchodilator spirometry value of FEV1/FVC<70% confirmed COPD diagnosis. COPD severity was classified according to the Global initiative for Obstructive Lung Disease (GOLD) guidelines 2015. Microalbuminuria was tested on early morning spot urine using CYBOW 12MAC microalbumin strips. UAlb was defined by Urine albumin to Creatinine ratio (ACR). Statistical Package for Social Sciences (SPSS) version 20 was used for data analysis. Results: Of the 104 enrolled COPD patients, 58 were known COPD and 46 were newly diagnosed COPD patients. The 46 newly diagnosed COPD patients underwent post bronchodilator COPD severity classification. Out of 104 participants, 16(15.4%) had co-morbid CVD, twenty-five (24.0%) had microalbuminuria and 26(29.8%) macroalbuminuria. The proportion of macro albuminuria was significantly higher in COPD patients with history of co morbid CVD than those without; (81.2% vs. 20.5%, p < 0.001). On the other hand microalbuminuria was significantly lower in those with CVD than those without CVD; (25.0% vs. 18.8%, p<0.001). The new 46 COPD patients underwent post bronchodilator COPD severity classification of whom, 60.9% (95%CIs 46.1–73.9) had moderate COPD and 30.4% (95%CIs, 17.9-49.0) severe COPD. Microalbuminuria increased significantly with COPD severity (p=0.049). Conclusion: Microalbuminuria was prevalent in patients regardless of coexistence of co morbid CVD. Microalbuminuria risk increased significant with COPD severity or with the decreased level of FEV1% predicted. Exclusion of other conditions that could give microalbuminuria was limited to history rather than laboratory markers. Therefore the degree of microalbuminuria may be overestimated. A few study participants had co morbid CVD based on medical history. Microalbuminuria seemed to be an important biomarker for the prediction of cardiovascular diseases in COPD patients. Detection of microalbuminuria will help to provide early treatment of these extra-pulmonary co-morbidities like CVD and consolidating the COPD management and therefore delaying progression of the disease and death. This is an important study in our country - Tanzania especially in this era of rapid emerging non communicable diseases on very limited health facilities.