Characteristics of participants according to AO and post-TB status
| Variables | P-TB (+)/AO (+) (n=130) | P-TB (−)/AO (+) (n=1230) | P-TB (+)/AO (−) (n=480) | P-TB (−)/AO (−) (n=6840) | P value* | P value† |
| Male | 75 (57.7%) | 627 (51.0%) | 253 (52.7%) | 3318 (48.5%) | 0.519 | 0.075 |
| Age group, years | 53.90 (14.66) | 42.34 (16.74) | 48.07 (15.13) | 38.98 (14.81) | <0.001 | <0.001 |
| City dwellers | 53 (40.8%) | 280 (22.8%) | 203 (42.5%) | 2300 (33.8%) | <0.001 | <0.001 |
| Education level | ||||||
| Primary school and lower | 93 (71.5%) | 576 (46.8%) | 269 (56.0%) | 2936 (42.9%) | <0.001 | <0.001 |
| Middle and high school | 30 (23.1%) | 517 (42.0%) | 150 (31.3%) | 2708 (39.6%) | ||
| College and higher | 7 (5.4%) | 137 (11.2%) | 61 (12.7%) | 1196 (17.5%) | ||
| Smoking status | ||||||
| Never smoker | 85 (65.4%) | 857 (69.7%) | 320 (66.7%) | 5009 (73.3%) | 0.595 | 0.002 |
| Ever smoker | 45 (34.6%) | 373 (30.3%) | 160 (33.3%) | 1828 (26.7%) | ||
| History of asthma | 16 (12.3%) | 28 (2.3%) | 16 (3.3%) | 90 (1.3%) | 0.428 | 0.005 |
| Respiratory symptoms | ||||||
| Frequent cough | 30 (23.3%) | 131 (10.7%) | 79 (16.5%) | 626 (9.3%) | 0.001 | <0.001 |
| Sputum | 31 (24.0%) | 125 (10.2%) | 79 (16.6%) | 625 (9.2%) | <0.001 | <0.001 |
| Recurrent wheezing | 18 (14.0%) | 65 (5.3%) | 36 (7.5%) | 245 (3.6%) | 0.079 | <0.001 |
| Dyspnoea in daily life | 48 (37.2%) | 257 (20.9%) | 150 (31.4%) | 1313 (19.4%) | <0.001 | <0.001 |
| At least one of the symptoms | 64 (49.6%) | 362 (29.5%) | 220 (46.0%) | 1897 (28.1%) | <0.001 | <0.001 |
| CAT score‡ | ||||||
| <10 | 22 (17.1%) | 322 (26.3%) | ||||
| ≥10 | 107 (82.9%) | 904 (73.7%) | ||||
| Lung function parameters | ||||||
| FVC post-BD, L | 3.53 (1.11) | 3.85 (1.02) | 3.58 (0.99) | 3.71 (0.94) | <0.001 | 0.004 |
| FVC post-BD % pred | 106.52 (28.16) | 108.47 (24.20) | 106.11 (24.83) | 103.42 (21.89) | 0.052 | 0.012 |
| FEV1 post-BD, L | 2.17 (0.85) | 2.48 (0.79) | 2.98 (0.85) | 3.17 (0.82) | <0.001 | <0.001 |
| FEV1 post-BD % pred | 79.41 (26.39) | 83.14 (21.53) | 106.28 (26.27) | 104.77 (22.42) | <0.001 | 0.157 |
| FEV1/FVC post-BD, % | 60.60 (10.44) | 64.15 (9.99) | 83.22 (7.08) | 85.66 (6.86) | <0.001 | <0.001 |
| MMEF post-BD % pred | 34.59 (17.63) | 45.21 (73.41) | 77.95 (32.87) | 84.60 (52.50) | <0.001 | 0.013 |
| FEF50% post-BD % pred | 40.74 (18.44) | 47.01 (17.64) | 94.84 (30.86) | 95.53 (27.09) | <0.001 | 0.587 |
| FEF75% post-BD % pred | 41.87 (34.86) | 48.82 (25.95) | 96.58 (57.56) | 99.72 (45.9) | <0.001 | 0.147 |
| SpO2, % | 92.24 (6.60) | 94.58 (4.68) | 91.17 (6.32) | 93.25 (5.31) | <0.001 | <0.001 |
Data are expressed as number (%) or mean (SD).
*P value difference between post-TB without airflow obstruction and airflow obstruction without post-TB.
†P value difference between normal population and post-TB without airflow obstruction.
‡CAT score difference for p<0.001.
AO, airflow obstruction; CAT, chronic obstruction pulmonary disease assessment test; FEF, forced expiratory flow; FEV1, forced expiratory volume in the first second; FVC, forced vital capacity; MMEF, maximum mid-expiratory flow; post-BD, post-bronchodilator; P-TB, post-tuberculosis; P-TB(−)/AO(+), airflow obstruction without post-TB; P-TB(−)/AO(−), normal population without airflow obstruction and post-TB; P-TB(+)/AO(−), post-TB without airflow obstruction; P-TB(+)/AO(+), airflow obstruction with post-TB; SpO2, oxyhemoglobin saturation.