Prevalence of post-tuberculosis airflow obstruction in patients who have completed pulmonary tuberculosis treatment at two infectious disease hospitals in Zimbabwe

Abstract

Tuberculosis (TB) is a major cause of death worldwide. About two thirds of patients develop impaired pulmonary function after completion of pulmonary TB treatment. It seems a high proportion of TB deaths are due to post-TB chronic airflow obstruction but data is lacking to support this assertion. Research question- What is the prevalence of post-tuberculosis airflow obstruction in patients who have completed pulmonary tuberculosis treatment at Wilkins and Beatrice Road Infectious Diseases Hospital (BRIDH)? Primary objective- To determine the prevalence of post-tuberculosis airflow obstruction in patients who have completed pulmonary tuberculosis treatment at Wilkins and BRIDH hospitals. Secondary objectives- 1 To identify factors that may influence lung function outcomes in post-TB patients. 2 To identify the pattern of spirometry values among post-TB patients. Design, Setting and Participants The study was a cross-sectional study at Wilkins and BRIDH hospitals in patients who had completed 6 months of anti-TB treatment. Sample size- Three hundred and twenty-seven patients. Methods Spirometry was done in patients who had completed 6 months of anti-TB treatment. Participants were recruited from Wilkins and BRIDH hospitals after an informed consent. Eligible were adults aged 18-65 years who have completed 6 months of anti-TB treatment. Those with a history of smoking, occupational exposure, asthma, COPD, interstitial lung disease and bronchiectasis were excluded. Results The prevalence of post-tuberculosis airflow obstruction was 65.7%. Restriction probable was found in 14.4% and normal spirometry in 19.9% of the participants. Female sex (p=0.020) and recurrent episodes of TB (p=0.026) were associated with development of post-TB airflow obstruction. Conclusion There is a high prevalence of post-tuberculosis airflow obstruction, with moderate obstruction according to the GOLD criteria being most prominent. Recurrent episodes of TB and female sex were associated with development of post-TB airflow obstruction.