Treatment outcome among Post TB obstructive airways diseases and COPD: A prospective cohort study

CONTEXT: Post Tubercular Obstructive Airways Diseases (Post-TB OAD) is a sequela of Pulmonary TB but diseases progression may not same like Chronic Obstructive Pulmonary Diseases (COPD). AIM: To compare the frequency and severity of exacerbations, change of FEV1, frequency of hospitalization and mortality among COPD and post TB OAD patients. SETTING AND DESIGN: Hospital-based prospective cohort study. METHODS AND MATERIAL: COPD cohort was diagnosed based on symptoms, history of exposure to risk factors and post bronchodilator FEV1/FVC ratio <70%. Post TB OAD cohort was diagnosed like COPD along with past history of Pulmonary TB. Both cohorts were followed up every 3-monthly intervals for up to 12 months. STATISTICAL ANALYSIS: Comparison of categorical variable was done by Chi-square test and continuous variable by unpaired t test. Longitudinal data of FEV1% were analyzed by repeated measure ANOVA test. RESULTS: Totally, 68 patients with Post TB OAD and 66 COPD patients were taken into this study. The frequency of exacerbation (3.52 ± 1.84 verses 2.70 ± 1.37), number of severe exacerbation (56 verses 24) and frequency of hospitalization (1.37 ± 0.81 verses 0.97 ± 0.94) more seen in post-TB OAD cohort in compared to COPD cohort which is statistically significant. Mortality more seen in post-TB OAD group (14 verses 6). Rate of decline FEV1 per year more seen in Post-TB OAD (0.27 ± 0.28 lit verses 0.17 ± 0.26 liter) as compared to COPD. There was overall decreasing trend of FEV1% over period of 12 month but without any difference among two cohort. CONCLUSION: There was more in frequency of exacerbations, number of severe exacerbations, frequency of hospitalization and number of mortalities among post TB OAD compared to COPD.