Table 2.
Variables Associated With Time to Treatment Failure
| Variables | Univariate analysis
|
Multivariate analysis
|
||||
|---|---|---|---|---|---|---|
| P value | HR | 95% CI | P value | HR | 95% CI | |
| Gender | .180 | |||||
| IBD type (UC vs CD) | <.001 | 2.1 | 1.4–3.1 | .005 | 1.8 | 1.2–2.6 |
| CD location | .649 | |||||
| CD behavior | .369 | |||||
| Age at diagnosis | .132 | |||||
| Age at start of IFX | .117 | |||||
| Duration from IFX initiation until start of TDM | .021 | 0.991 | 0.983–0.999 | |||
| UC extension | .359 | |||||
| Perianal fistulizing disease | .050 | |||||
| Ileocolonic resection prior to TDM | .260 | |||||
| Concomitant IMM at start of TDM | .569 | |||||
| Anti-TNF naive | .699 | |||||
| Smoking ever | .150 | |||||
| IFX dosing other than 5 mg/Kg q8w at start of TDM | .051 | |||||
| IFX concentration at start of TDM | <.001 | 0.93 | 0.89–0.97 | |||
| ATI at start of TDM | <.001 | 2.9 | 1.9–4.5 | .024 | 1.8 | 1.1–2.9 |
| Proactive TDM | <.001 | 0.12 | 0.07–0.21 | <.001 | 0.16 | 0.09–0.27 |
ATI, antibodies to infliximab; CD, Crohn’s disease; CI, confidence interval; HR, hazard ratio; IBD, inflammatory bowel disease; IFX, infliximab; IMM, immunomodulators; TDM, therapeutic drug monitoring; TNF, tumor necrosis factor; UC, ulcerative colitis.