Acute Severe Ulcerative Colitis Patients From Asia Have Lower Colectomy Risk Than Patients From Australasia

The incidence of ulcerative colitis (UC) and acute severe UC (ASUC) is rapidly increasing in Asia but remains lower than Australia and New Zealand (ANZ). Studies in Asian countries report differences in UC characteristics and lower colectomy risk. We aimed to compare ASUC characteristics and outcomes in Asia and ANZ.

This was a multinational, multicenter retrospective cohort study of consecutive patients hospitalized with ASUC meeting Truelove and Witts' criteria from January 2015 to December 2020, across 14 hospitals in 4 Asian countries and 9 ANZ hospitals.

A total of 861 patients were included, with 430 from Asia and 431 from ANZ. Baseline characteristics in the Asian and ANZ cohorts differed significantly, most notably with the Asian cohort having a lower proportion with an IBD family history (P < .001), more extensive disease at diagnosis (P < .001), and worse endoscopic severity (P < .001). At admission, significantly less Asian patients were currently taking corticosteroids, thiopurines, and biologics, and less had previous exposure to biologics (P < .005). More Asian patients were discharged on 5-aminosalicylates (P = .014), and fewer were prescribed corticosteroids (P = .049), thiopurines (P < .001), or advanced therapies (P < .001) on discharge, but more remained corticosteroid-dependent on follow-up (P < .029). The Asian cohort had lower rates of corticosteroid failure (21.5% vs 57.2%; P < .001), inpatient colectomy (2.8% vs 10.9%; P < .001), 1-year colectomy (4.7% vs 22.5%; P < .001), and readmission with ASUC within 12 months (9.3% vs 16.1%; P < .001), validated using a propensity score matched cohort.

The characteristics of patients with ASUC in Asia differ significantly from ANZ. Despite worse endoscopic severity and more extensive disease, the Asian ASUC cohort appears more corticosteroid-responsive with significantly lower colectomy rates and less requirement for advanced therapies.