Trends in Length of Stay, Steroid Use and Colectomy Rates in Patients Admitted with Acute Severe Ulcerative Colitis: The Impact of Accelerated and Intensified Infliximab Dosing

The optimal dose of infliximab in patients with acute severe ulcerative colitis (ASUC) with inadequate intravenous steroid response remains unclear. We aimed to evaluate infliximab dosing on outcomes of patients with ASUC.

A retrospective review of medical records was performed for patients with ASUC; grouped by cumulative infliximab dose administered during the first 14 days: standard (5 mg/kg) or intensified/accelerated (10-15 mg/kg or ≥ 20 mg/kg). Outcomes included prescribing patterns over time, length of stay, and 12-month readmission, colectomy and steroid requirement, as well as safety.

Of 213 patients admitted with UC, 147 met criteria for ASUC. 83 patients (28 [34%] female, median age 33 [IQR 24.5-48] years) received infliximab (29 [35%] 5 mg/kg, 35 [42%] 10-15 mg/kg and 19 [23%] ≥ 20 mg/kg). Intensified/accelerated infliximab dosing (≥ 10 mg/kg) increased from 2016-2019 (26%) to 2020-2024 (76.5%) (p = 0.015), correlating with overall reduction in 12-month colectomy rates from 13.6% in 2016-2019 to 2.5% in 2020-2024 (p = 0.014). Disease severity was higher in patients receiving intensified/accelerated dosing. Median length of stay was shorter in those receiving 5 mg/kg and 10-15 mg/kg than ≥ 20 mg/kg (6 vs 11 days, p = 0.001). No difference was seen in colectomy or readmission rates or 30-day infective complications following different infliximab doses. 12-month steroid requirement was lower with following ≥ 20 mg/kg (median 1600 mg) than 5 mg/kg (1850 mg), p = 0.038.

Intensified/accelerated infliximab prescription in patients with ASUC increased over the past decade, correlating with reduced colectomy rates. Despite higher disease severity, colectomy and 12-month readmission rates were similar across dosage groups, with 12-month steroid requirement less after ≥ 20 mg/kg than 5 mg/kg.