Serum cystatin C and serum adenosine deaminase level in patients with stable and exacerbated chronic obstructive pulmonary disease: a cross-sectional comparative study.

Abstract

Objectives: The aim of this study was to measure and compare the serum levels of cystatin C and ADA between stable and exacerbated COPD.

Methods: The study was designed as a cross-sectional comparative study. Cases were defined as subjects who presented in the outpatient and inpatient departments with COPD and were stratified to stable COPD and acute exacerbation of COPD. Controls were healthy age-matched subjects who are not on any drugs and were nonsmokers. Association between cystatin C and ADA between stable and exacerbated COPD was assessed using logistic regression.

Results: There were a total of 182 subjects included in the study, of which, 63 had acute exacerbated COPD, 60 had stable COPD, and 59 were heathy controls. Logistic regression analysis showed that cystatin C (OR, 1.33, 95% CI: 1.16-2.56) and CRP (OR, 2.26, 95% CI: 1.59-2.69) levels were significantly higher, while ADA (OR, 0.82, 95% CI: 0.59-0.91) levels were significantly lower among those with stable COPD, compared to healthy controls. Similarly, cystatin C (OR, 1.48, 95% CI: 1.12-2.12) and CRP (OR, 3.39, 95% CI: 2.34-3.89) levels were significantly higher, while ADA (OR, 0.62, 95% CI: 0.41-0.87) levels were significantly lower among those with acute exacerbated COPD, compared to healthy controls.

Conclusion: Cystatin C and c-reactive protein (CRP) were significantly elevated, while ADA was significantly reduced in both stable and acute exacerbated COPD. Future large-scale studies should further explore the value of these markers in predicting the severity of COPD.