Longitudinal Lung Function Decrease in Subjects with Spontaneous Healed Pulmonary Tuberculosis

Objective We compared the longitudinal course of post-bronchodilator Forced Expiratory Volume in 1 second (pFEV1) over a 10-year period in subjects with spontaneous healed pulmonary tuberculosis (SHPTB) with that in normal subjects. Methods We prospectively investigated 339 subjects with SHPTB and 3211 normal subjects. pFEV1 values measured biannually over 10 years were analyzed using mixed effects model. Results At baseline, there were no differences in gender, smoking amount, and mean height, except mean age (50.0 +/- 8.1 VS. 48.1 +/- 7.3, P<0.001) between the SHPTB and normal group. 52% of the 339 participants with SHPTB and 56% of the 3211 normal participants participated till the end of study. According to the final model, the SHPTB group showed significantly larger decrease in the average pFEV1 over the time than the normal group (P<0.001) adjusted for gender, age, height, smoking pack years, and time effects. Especially, the interaction effect between time and group was statistically significant (P = 0.036). Conclusion The average lung function in terms of pFEV1 decreases faster in subjects with SHPTB than in normal individuals over time.