Microalbuminuria and High-Sensitivity C-Reactive Protein as Potential Biomarkers of Systemic Inflammation in Patients with Chronic Obstructive Pulmonary Disease

ABSTRACT

Abstract There isn't yet a clear definition for systemic inflammation in COPD (chronic obstructive pulmonary disease), but its recognition has been based on studies that show an increase in the plasma concentration of various inflammatory markers, such as the c-reactive protein (CRP), and in recent years, also the microalbuminuria has been suggested. The purposes of this work were to determine the microalbuminuria and CRP as potential biomarkers of systemic inflammation. We enrolled patients with stable COPD and non-COPD smokers diagnosed through spirometry; older than 40 years without AHT (arterial hypertension) or diabetes type I or II, between October 2017 and March 2019. In both groups, a venous blood sample was collected to determine high-sensitivity CRP and 3 urine samples were taken to determine microalbuminuria, calculating the mean value. At least two out of three determinations between 30 and 300 mg/g of urine creatinine were considered to be significant albuminuria. The high-sensitivity CRP was considered positive with a value ≥ 5 mg/L. Of the 47 analyzed patients, a mean albuminuria of 13.91 ± 5.04 was obtained in the COPD group, in comparison with 2.50 ± 0.36 in the control group. Also, the high-sensitivity CRP mean values were compared, showing 5.06 ± 2.24 in COPD patients and 2.46 ± 0.51 in the control group. Both variables showed non-statistically significant differences between the study groups (p = 0.058 for mean albuminuria and p = 0.330 for high-sensitivity CRP).