Correlation analysis between H2S in sputum and serum and other parameters related to COPD
| Variables | Sputum H2S | Serum H2S | ||
|---|---|---|---|---|
| Crude | Adjusted† | Crude | Adjusted† | |
| β value (95% CI) | β value (95% CI) | β value (95% CI) | β value (95% CI) | |
| MRC score | 6.006 (3.258 to 8.754)*** | – | 14.83 (0.781 to 28.87)* | – |
| SGRQ score | 0.200 (0.066 to 0.333)** | – | 0.685 (0.005 to 1.366)* | – |
| Baseline SpO2 (%) | −1.860 (−3.386 to −0.335)* | – | −9.415 (−15.73 to −3.098)** | – |
| 6 MWD (m) | −0.084 (−0.122 to −0.045)*** | −0.065 (−0.117 to −0.013)* | −0.218 (−0.405 to −0.031)* | – |
| FEV1%predicted (%) | −0.337 (−0.452 to −0.222)*** | −0.272 (−0.430 to −0.114)** | −1.161 (−1.749 to −0.573)*** | −1.167 (−1.989 to −0.346)** |
| FEV1/FVC (%) | −0.441 (−0.612 to −0.270)*** | −0.341 (−0.575 to −0.106)** | −1.426 (−2.291 to −0.560)** | −1.271 (−2.522 to −0.020)* |
| TLCO (%) | −0.333 (−0.524 to −0.143)*** | −0.261 (−0.491 to −0.031)** | −0.621 (−1.661 to 0.420) | – |
| KCO (%) | −0.275 (−0.460 to −0.099)** | – | −0.594 (−1.561 to 0.412) | – |
| Sputum macrophages (%) | −0.364 (−0.465 to −0.263)*** | −0.331 (−0.446 to −0.216)*** | −0.864 (−1.508 to −0.221)** | – |
| Sputum neutrophils (%) | 0.353 (0.251 to 0.454)*** | 0.309 (0.193 to 0.424)*** | 0.868 (0.223 to 1.512)** | – |
| Serum IL8 (pg/mL) | 0.409 (0.045 to 0.773)* | – | 1.768 (0.184 to 3.352)* | – |
| Serum IL6 (pg/mL) | 0.912 (−0.923 to 2.748) | – | 10.62 (2.522 to 18.72)* | – |
| Sputum IL8 (pg/mL) | 0.017 (0.009 to 0.024)*** | 0.013 (0.005 to 0.022)** | 0.012 (−0.036 to 0.059) | – |
| Sputum IL6 (pg/mL) | 0.038 (0.010 to 0.066)** | – | −0.075 (−0.284 to 0.134) | – |
Data are presented as β value and 95% CIs. *p<0.05, **p<0.01, ***p<0.001.
†Adjusted for age, gender, height, weight, and smoking status.
6MWD, 6 minute walk distance; KCO, carbon monoxide diffusing capacity adjusted for alveolar volume; KCO, TLCO/Alveolar volume (Va); MRC, Medical Research Council; SGRQ, St. George’s Respiratory Questionnaire; TLCO, Transfer factor of the lung for carbon monoxide.