Medicina Pulmonar e Respiratória

Microalbuminuria and Hypoxemia in Patients with COPD

Abstract

Khalid Mehmood and Fayaz Ahmad Sofi

Background: Microalbuminuria (MAB), a marker of endovascular dysfunction, is a predictor of cardiovascular events and all-cause mortality in the general population. There is evidence of vascular dysfunction in patients with chronic obstructive pulmonary disease (COPD).

Objectives: (i) To evaluate the practical role of microalbuminuria in patients with COPD. (ii) To establish relationship between degree of Microalbuminuria and Hypoxemia in COPD. (iii) To study the frequency of microalbuminuria in stable COPD patients.

Study design: The study was prospective, conducted jointly in the Department of Internal medicine and Department of Immunology and Molecular Medicine at Sher-e-kashmir institute of medical sciences, srinagar(india), over a period of two years. Stable COPD patients without any comorbidity, with wide range of airflow obstruction were taken in study. Age matched smokers of more than 10 pack-years without airflow obstruction served as controls.

Methods: We measured spot urinary albumin, smoking history, arterial blood pressure, body mass index, lung function, kidney function tests and BODE index in 97 patients with stable COPD and 94 age matched smokers with normal spirometry without known cardiovascular disease. MAB levels were compared between groups. A multivariate analysis was performed to determine the best determinants of MAB levels.

Results: Microalbuminuria was more frequent in COPD patients compared to smokers without obstruction (20.6% versus 7.4%respectively); p=0.007. There was an inverse association of the PO2 and MAB in patients with COPD (r=-0.35, p<0.0001). Multivariate analysis with MAB as the dependent variable Showed that PO2 (odds ratio: 1.003; 95%CI, 0.767-0.974; p=0.021) was only independent and significant predictor of MAB.

Conclusions: MAB is frequent in patients with COPD and is associated with hypoxemia independent of other cardiovascular risk factors.