Background & aims: Long-term safety data for infliximab and other therapies in Crohn's disease (CD) are needed.
Methods: We prospectively evaluated patients for prespecified safety-related outcomes.
Results: As of August 2004, 6290 patients were enrolled; 3179 received infliximab (5519 patient-years), 87% of whom received at least 2 infusions, and 3111 received other therapies (6123 patient-years). The mean length of follow-up evaluation was 1.9 years. More infliximab-treated patients had moderate-to-severe (30.8% vs 10.3%) or severe-fulminant (2.5% vs .6%) CD, and had surgical (17.5% vs 13.8%) or medical (14.4% vs 9.1%) hospitalizations in the previous year. More patients were taking prednisone (27.4% vs 16.1%), immunomodulators (49.4% vs 32.2%), or narcotic analgesics (9.8% vs 5.4%) when compared with those receiving other therapies (P<.001, all comparisons). The mortality rates were similar for infliximab- and non-infliximab-treated patients (.53 per 100 patient-years vs .43; relative risk, 1.24; 95% confidence interval [CI], .73-2.10). In multivariate logistic regression analysis, only prednisone was associated with an increased mortality risk (odds ratio [OR], 2.10; 95% CI, 1.15-3.83; P=.016). Although the unadjusted analysis showed an increased risk for infection with infliximab use, multivariate logistic regression analysis suggested that infliximab was not an independent predictor of serious infections (OR, .99; 95% CI, .64-1.54). Factors independently associated with serious infections included prednisone use (OR, 2.21; 95% CI, 1.46-3.34; P<.001), narcotic analgesic use (OR, 2.38; 95% CI, 1.56-3.63; P<.001), and moderate-to-severe disease activity (OR, 2.11; 95% CI, 1.10-4.05; P=.024).
Conclusions: Mortality rates were similar between infliximab- and non-infliximab-treated patients. The increased risk for serious infection observed with infliximab likely was owing to disease severity and prednisone use.