Table 3.
Multivariable Cox proportional hazards model, propensity score-adjustment, and IPTW analyses of the effect of co-administration of PPIs on overall survival of the entire population (capecitabine monotherapy and CapeOX regimen).
| Multivariable analysis | Adjusted for propensity score | IPTW | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Variables | No. | Event | Censored | HR (95% CI) | P-value | Posterior probability | HR (95% CI) | P-value | Posterior probability | HR (95% CI) | P-value | Posterior probability | |
| PPI | Yes | 54 | 8 | 46 | 1.26 (0.58–2.71) | 0.560 | 0.308 | 1.12 (0.53–2.40) | 0.767 | 0.422 | 1.21 (0.54–2.73) | 0.642 | 0.347 |
| No | 552 | 66 | 486 | 1 | 1 | 1 | |||||||
| Age (10-year intervals) | – | – | – | 0.95 (0.76–1.20) | 0.683 | ||||||||
| Sex | Male | 328 | 48 | 280 | 1.57 (0.97–2.56) | 0.066 | |||||||
| Female | 278 | 26 | 252 | 1 | |||||||||
| Primary site | Right-sided colon | 171 | 26 | 145 | 1.27 (0.78–2.08) | 0.336 | |||||||
| Others | 435 | 48 | 387 | 1 | |||||||||
| Stage | III high-risk | 199 | 47 | 152 | 2.78 (1.23–6.29) | 0.014 | |||||||
| III low-risk | 334 | 20 | 314 | 0.63 (0.27–1.50) | 0.300 | ||||||||
| II | 73 | 7 | 66 | 1 | |||||||||
| Regimen | CapeOX | 157 | 24 | 133 | 0.95 (0.55–1.64) | 0.855 | |||||||
| Capecitabine | 449 | 50 | 399 | 1 | |||||||||
| RDI (10% intervals) | – | – | – | 0.88 (0.80–0.97) | 0.011 | ||||||||
Abbreviations: CapeOX, capecitabine and oxaliplatin; CI, confidence interval; HR, hazard ratio; IPTW, inverse probability of treatment weighting; PPI, proton pump inhibitor; RDI, relative dose intensity.