Cumulative incidence and risk factors for hospitalization and surgery in a population-based cohort of ulcerative colitis

Abstract

Background: We sought to identify clinical and demographic features influencing hospitalization and colectomy in a population-based inception cohort of ulcerative colitis.

Methods: Between 1970 and 2004, a total of 369 patients (58.5% males) from Olmsted County, MN, were followed from diagnosis for 5401 person-years. The cumulative probability of hospitalization and colectomy were estimated using the Kaplan-Meier method. Cox proportional hazards regression was used to identify factors associated with hospitalization and colectomy.

Results: The cumulative probability of first hospitalization was 29.4% at 5 years (95% confidence interval [CI], 24.5%-34.1%), 38.7% at 10 years (33.1%-43.8%), 49.2% at 20 years (42.7%-55.2%), and 52.3% at 30 years (45.1%-59.7%). The incidence rate of hospitalizations decreased over the last 4 decades, although cumulative probability of first hospitalization increased with successive decades of diagnosis. Early need for corticosteroids (hazard ratio [HR], 1.8; 95% CI, 1.1%-2.7%) and early need for hospitalization (HR, 1.5; 95% CI, 1.02-2.4) were independent predictors of hospitalization after 90 days of illness. The cumulative probability of colectomy from the time of diagnosis was 13.1% at 5 years (95% CI, 9.4%-16.6%), 18.9% at 10 years (95% CI, 14.4%-23.2%), and 25.4% at 20 years (95% CI, 19.8%-30.8%). Male gender (HR, 2.1; 95% CI, 1.3-3.5), diagnosis in the 1990s (HR, 2.0; 95% CI, 1.01-4.0), and diagnosis in 2000 to 2004 (HR, 3.7; 95% CI, 1.7-8.2) were significantly associated with colectomy risk.

Conclusions: Colectomy rates were comparable to reports from northern Europe. The numbers of hospitalizations show a decreasing trend. Male gender and being diagnosed in the 2000 to 2004 period predicted colectomy while extensive colitis predicted future hospitalizations.

FIGURE 1

Unadjusted incidence rates of any ulcerative colitis-related hospitalization, surgical hospitalization, and medical hospitalization among 369 patients with ulcerative colitis from Olmsted County, Minnesota, 1970–2004, stratified by calendar period of observation.

FIGURE 2

Cumulative incidence of first ulcerative colitis-related hospitalization among 369 patients with ulcerative colitis from Olmsted County, Minnesota, 1970–2004. A. Overall cumulative incidence. B. Cumulative incidence stratified by decade of diagnosis. C. Cumulative incidence stratified by disease extent measured within first 90 days of diagnosis. D. Cumulative incidence stratified by requirement for corticosteroids within the first 90 days. E. Cumulative incidence stratified by requirement for hospitalization within the first 90 days.

FIGURE 2

Cumulative incidence of first ulcerative colitis-related hospitalization among 369 patients with ulcerative colitis from Olmsted County, Minnesota, 1970–2004. A. Overall cumulative incidence. B. Cumulative incidence stratified by decade of diagnosis. C. Cumulative incidence stratified by disease extent measured within first 90 days of diagnosis. D. Cumulative incidence stratified by requirement for corticosteroids within the first 90 days. E. Cumulative incidence stratified by requirement for hospitalization within the first 90 days.

FIGURE 2

Cumulative incidence of first ulcerative colitis-related hospitalization among 369 patients with ulcerative colitis from Olmsted County, Minnesota, 1970–2004. A. Overall cumulative incidence. B. Cumulative incidence stratified by decade of diagnosis. C. Cumulative incidence stratified by disease extent measured within first 90 days of diagnosis. D. Cumulative incidence stratified by requirement for corticosteroids within the first 90 days. E. Cumulative incidence stratified by requirement for hospitalization within the first 90 days.

FIGURE 3

Cumulative incidence of colectomy among 369 ulcerative colitis patients from Olmsted County, Minnesota, 1970–2004. A. Overall cumulative incidence. B. Cumulative incidence stratified by calendar period of diagnosis. C. Cumulative incidence stratified by gender.

FIGURE 3

Cumulative incidence of colectomy among 369 ulcerative colitis patients from Olmsted County, Minnesota, 1970–2004. A. Overall cumulative incidence. B. Cumulative incidence stratified by calendar period of diagnosis. C. Cumulative incidence stratified by gender.