Outcome Evaluation in Acute Exacerbation of COPD On the Basis of Serum Gamma-Glutamyl Transferase Level

Abstract

Background: Chronic obstructive pulmonary disease (COPD) is a huge burden to the health care facility worldwide that is both substantial and increasing. Exacerbations of COPD have a negative impact on health status, rates of hospitalization and disease progression. However, there is still a lack of effective biomarkers to monitor COPD and its acute exacerbation. One of the most important factors in the pathogenesis of COPD is oxidative stress. GGT (gamma-glutamyl transferase) has been regarded as a novel marker of oxidative stress over the last few years. This aim of the study was to assess serum GGT level during acute exacerbation of COPD and to evaluate its role in monitoring the outcome of COPD exacerbation. We also tried to correlate serum GGT level with severity of COPD, respiratory failure and patients’ degree of dyspnoea. Materials and Methods: This was a hospital based longitudinal study and was conducted at the department of Respiratory Medicine, National Institute of Diseases of the Chest & Hospital (NIDCH), Dhaka, Bangladesh over a period of one year. Following informed written consent, total 50 patients with acute exacerbation of COPD were included into the study. All patients were interviewed and they were subjected to do physical examination along with relevant investigations by researcher with a pretested questionnaire. Serum GGT level was detected during admission, on day 3 and the day before discharge or other outcomes. In all cases, ethical issues were maintained properly and collected data were analysed by SPSS 23. Results: Mean GGT was found 141.4±76.3 U/L at admission, 137.4±87.2 U/L on day 3 after admission and 85.5±45.0 U/L on the day before discharge. Negative correlation (r= - 0.434; p=0.002) was observed between FEV1(% predicted) and GGT at admission whwereas positive correlation (r= 0.857; p=0.001) was present between PCO2 and GGT at admission. Mean GGT at admission was found to be higher in those referred to RCU/ICU group than those not requiring referral to RCU/ICU group and the difference was statistically significant (p<0.05). Serum GGT value e”103.5 U/L was associated with acute exacerbation of COPD requiring hospitalization, serum GGT level of e”141.5 U/L displayed a reliable prediction of referral to RCU/ICU and GGT level of e”194.0 U/L could be applied to predict an increased risk of mortality. Conclusion: This study demonstrates that serum GGT can be used as an effective biomarker to access the severity and predict the outcome in patients with acute exacerbation of COPD. The monitoring of GGT values can be useful during the progression of COPD exacerbation and assessment of serum GGT should be made readily available and easily accessible at all tertiary level hospitals in our country. Chest Heart J. 2023; 47(2) : 118-128