Effect of Long-Term Oxygen Therapy in Chronic Obstructive Pulmonary Disease: A Prospective Clinical Study

Abstract

Introduction: Long-Term Oxygen Therapy (LTOT) has the potential to improve the mortality and morbidity in Chronic Obstructive Pulmonary Disease (COPD) patients. Aim: To assess the effect of LTOT on the Quality of Life (QoL) in stable COPD patients with severe resting hypoxemia. Materials and Methods: This was a prospective observational study conducted in a tertiary care teaching hospital in Kozhikode, Kerala, on stable COPD patients with severe hypoxemia who were newly initiated on home LTOT for ≥15 hours per day. Health Related Quality of Life (HRQoL), modified Medical Research Council (mMRC) grade of dyspnoea, frequency of exacerbations and adherence to treatment on LTOT were studied. Total of 60 patients were followed-up for one year. Significance of mean was tested using paired t-test and association between qualitative variables was tested using Chi-square test. The p-value <0.05 was considered statistically significant. Results: Out of all, 7 patients died during the study period and 53 patients were included in the final analysis. The mean total St.George’s Respiratory Questionnaire (SGRQ) scores at 3, 6 and 12 months improved to 53.73±13.2, 53.97±13.22 and 54.63±13.16, respectively, from a baseline score of 72.51±8.88. At the end of 12 months of LTOT, 22 (41.51%) patients did not have exacerbations and 31 (58.49%) patients had exacerbations. There was no statistically significant improvement in dyspnoea after one year of LTOT. Among the 53 patients, who completed one year follow-up, 36 (67.92%) participants were adherent and remaining 17 (32.07%) participants were non adherent to LTOT. Conclusion: LTOT improves the HRQoL in stable COPD patients with severe hypoxemia. Use of domiciliary oxygen for at least 15 hours per day can reduce the number of COPD exacerbations.