EVALUATION OF THE ROLE OF URIC ACID, CREATININE RATIO, AND ALBUMIN-CREATININE RATIO AS PROGNOSTIC MARKERS IN ASSESSING SEVERITY OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) WITH CORRELATION TO DEMOGRAPHIC PROFILE AND SPIROMETRY PARAMETERS

Abstract

Background: Chronic obstructive pulmonary disease (COPD) is a progressive and debilitating respiratory disorder characterized by persistent airflow limitation, chronic inflammation, and structural alterations in the airways. It represents a major global health burden and is currently one of the leading causes of morbidity and mortality worldwide, particularly in low- and middle-income countries. Although spirometry remains the gold standard for diagnosis and staging, it does not adequately reflect the systemic nature of COPD or predict disease progression and outcomes. Increasing evidence suggests that COPD is associated with systemic inflammation, oxidative stress, and endothelial dysfunction, which contribute to extrapulmonary manifestations and poorer prognosis. In this context, biochemical markers such as uric acid creatinine ratio (UA/Cr), reflecting hypoxia-induced metabolic stress, and albumin–creatinine ratio (ACR), indicating endothelial dysfunction and microvascular damage, have emerged as potential prognostic indicators. However, their combined role in assessing COPD severity and correlation with spirometric parameters remains inadequately explored. Objectives: To evaluate the role of UA/Cr ratio and ACR as prognostic markers in assessing COPD severity and to correlate these biomarkers with demographic profile and spirometry parameters. Methods: This hospital-based cross-sectional analytical study was conducted among 100 COPD patients from July 2025 to January 2026. Diagnosis and severity classification were based on GOLD criteria. Serum uric acid, serum creatinine, and urinary albumin were measured, and UA/Cr ratio and ACR were calculated. Spirometry parameters including FEV₁, FVC, and FEV₁/FVC ratio were recorded. Statistical analysis included ANOVA, correlation analysis, and logistic regression. Results: The mean UA/Cr ratio increased significantly from 4.2 ± 0.8 in Stage I to 9.1 ± 1.8 in Stage IV (p < 0.001). ACR increased from 18 ± 6 mg/g to 110 ± 22 mg/g across stages (p < 0.001). Both markers showed significant negative correlations with spirometry, with ACR showing stronger correlation with FEV₁ (r = -0.68) compared to UA/Cr (r = 0.62). UA/Cr ≥7 and ACR ≥60 mg/g were associated with higher odds of severe COPD (OR 6.5 and 8.2). ACR (AOR 5.6), UA/Cr (AOR 4.3), and smoking (AOR 2.8) were independent predictors. Conclusion: UA/Cr ratio and ACR are significant independent predictors of COPD severity. Their combined use with spirometry may improve risk stratification and clinical decision-making.