B69-06 Quality of Pulmonary Function Testing in Individuals With Pulmonary Tuberculosis

Abstract Rationale Despite growing awareness of pulmonary impairment among people diagnosed with pulmonary tuberculosis (TB), there are limited data on the performance of acceptable pulmonary function testing (PFT) in settings with a high TB burden. This analysis examines the quality of comprehensive PFTs achieved with TB treatment and whether disease severity at diagnosis is associated with the ability to complete acceptable PFTs. Methods In this prospective cohort study in Johannesburg, South Africa, adults with and without HIV co-infection were enrolled at the time of rifampin-susceptible TB diagnosis. Comprehensive PFTs, including spirometry, lung volumes by multiple breath washout, and DLCO, were collected at baseline (14 days of treatment initiation), 1-month, 6-month, and 12-month timepoints. PFTs were evaluated by a pulmonologist per American Thoracic Society/European Respiratory Society guidelines. A test was considered acceptable if at least one maneuver was acceptable. Logistic regression was used to characterize the association between disease severity on chest x-ray and the ability to perform acceptable PFTs. Results At baseline, 95% of participants successfully completed spirometry and 61% successfully completed all three PFT maneuvers. The proportion of participants able to successfully complete all three PFT maneuvers was 77% at 1 month, 72% at 6 months (end of TB treatment), and 71% at 12 months. Participants able to complete acceptable maneuvers at baseline were younger (median age 35 vs. 37 years, p = 0.03) and had less extensive disease on chest x-ray (51% vs. 68% with far advanced disease, p = 0.03). In a multivariable model adjusted for age, gender, and HIV status, far advanced disease on chest X-ray was associated with lower odds of acceptable maneuvers at baseline (OR 0.49, CI 0.26 - 0.96, p = 0.04). Conclusion Although the majority of individuals being treated for pulmonary TB were able to perform comprehensive PFTs, those with more advanced radiographic disease were less likely to perform acceptable maneuvers during early treatment. The quality of PFTs increased after the baseline visit, which could reflect clinical improvement or greater familiarity with testing. Future analyses will further characterize barriers to performing acceptable PFT maneuvers during and after TB treatment, which will inform ongoing studies of post-TB lung disease. This abstract is funded by: NIAID R01 AI 166988