Effect of bariatric surgery on lung function
| NBS+A | BS+A | BS−A | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Baseline | 12-month FU | p Value* | Baseline | 12-month FU | p Value* | Baseline | 12-month FU | p Value* | |
| Spirometry | |||||||||
| FEV1, pre (% predicted) | 88 (45–106) | 81 (71–117) | 0.553 | 86 (66–119) | 95 (67–119) | <0.001 | 97 (73–125) | 106 (75–134) | <0.001 |
| FEV1, post (% predicted) | 95 (49–106) | 88 (70–118) | 0.759 | 93 (75–118) | 100 (79–117) | 0.001 | 101 (75–129) | 108 (80–139) | <0.001 |
| FVC, pre (% predicted) | 102 (64–118) | 103 (77–131) | 0.683 | 96 (75–126) | 105 (75–131) | 0.001 | 106 (77–144) | 109 (87–149) | 0.009 |
| FVC, post (% predicted) | 107 (62–120) | 106 (78–131) | 0.721 | 99 (74–126) | 107 (77–123) | 0.002 | 107 (78–141) | 107 (84–149) | 0.046 |
| FEV1/FVC, pre (%) | 79 (61–90) | 78 (63–83) | 0.550 | 76 (63–92) | 77 (57–92) | 0.246 | 81 (66–93) | 83 (73–99) | 0.021 |
| FEV1/FVC, post (%) | 82 (69–91) | 78 (66–86) | 0.239 | 79 (67–94) | 81 (69–94) | 0.327 | 84 (68–94) | 87 (77–98) | <0.001 |
| RV, post (% predicted)† | 79 (74–92) | 65 (55–105) | 0.285 | 80 (39–126) | 79 (76–115) | 0.789 | 72 (47–96) | 82 (43–137) | 0.013 |
| TLC, post (% predicted)† | 83 (77–102) | 87 (74–105) | 0.414 | 6 (83–106) | 104 (79–115) | 0.018 | 96 (75–114) | 101 (81–122) | <0.001 |
| FRC, post (% predicted)† | 65 (54–90) | 69 (61–85) | 0.593 | 62 (40–95) | 88 (53–117) | 0.008 | 64 (41–77) | 94 (59–145) | <0.001 |
| RV/TLC, post (%)† | 28 (25–36) | 22 (20–40) | 0.285 | 20 (10–41) | 22 (15–29) | 0.767 | 25 (15–33) | 28 (11–40) | 0.054 |
| FeNO (ppb)‡ | 16 (7–96) | 14 (8–58) | 0.097 | 18 (8–45) | 15 (8–32) | 0.477 | 15 (7–53) | 14 (5–67) | 0.687 |
| Diffusion capacity, kCO (% predicted) | 98 (70–116) | 95 (71–136) | 0.202 | 97 (69–133) | 99 (67–118) | 0.483 | 95 (77–134) | 91 (69–127) | 0.179 |
| PD20 methacholine (mg) | 0.23 (0.09–1.31) | 0.92 (0.19–1.8) | 0.273 | 0.22 (0.04–1.40) | 1.46 (0.04–1.8) | 0.001 | |||
Data are presented as median (min–max).
*p Value for comparison baseline versus 12-month follow-up within each group. †Because of weight limitations for the body box (<150 kg), full spirometry could not be performed in all subjects; numbers for these parameters: NBS+A=3, BS+A=12, BS−A=27.
‡Log transformed for statistical purposes.
BS+A, bariatric surgery and asthma group; BS−A, bariatric surgery without asthma group; FeNO, exhaled nitric oxide; FRC, functional residual capacity; FU, follow-up; NBS+A, no bariatric surgery and asthma group; PD20, provocative dose of methacholine inducing a 20% fall in FEV1; RV, residual volume; TLC, total lung capacity.