A population-based study of incidence, risk factors, clinical spectrum, and outcomes of ischemic colitis

Abstract

Background & aims: Little is known about progression of ischemic colitis (IC) among unselected patients. We aimed to estimate the incidence, risk factors, and natural history of IC in a population-based cohort in Olmsted County, Minnesota.

Methods: We performed a retrospective population-based cohort and nested case-control study of IC. Each IC case was matched to 2 controls from the same population on the basis of sex, age, and closest registration number. Conditional logistic regression, the Kaplan-Meier method, and proportional hazards regression were used to assess comorbidities, estimate survival, and identify characteristics associated with survival, respectively.

Results: Four hundred forty-five county residents (median age, 71.6 years; 67% female) were diagnosed with IC from 1976 through 2009 and were matched with 890 controls. The age-adjusted and sex-adjusted incidence rates of IC nearly quadrupled from 6.1 cases/100,000 person-years in 1976-1980 to 22.9/100,000 in 2005-2009. The odds for IC were significantly higher among subjects with atherosclerotic diseases; odds ratios ranged from 2.6 for individuals with coronary disease to 7.9 for individuals with peripheral vascular disease. Of IC cases, 59% survived for 5 years (95% confidence interval, 54%-64%), compared with 90% of controls (95% confidence interval, 88%-92%). Age >40 years, male sex, right-sided colon involvement, concomitant small bowel involvement, and chronic obstructive pulmonary disease were all independently associated with mortality (P < .05).

Conclusions: The incidence of IC increased during the past 3 decades in a population-based cohort in Minnesota. IC typically presents in older patients with multiple comorbidities and is associated with high in-hospital mortality (11.5%) and rates of surgery (17%).

Keywords: COPD; Cardiovascular Disease; Epidemiologic Study; Intestinal Vasculature.

Figure 1

A. Age-specific incidence of ischemic colitis in males, females and together in both sexes among Olmsted County, Minnesota, residents 1976-09. B. Age-adjusted incidence rate of ischemic colitis in males, females and together in both sexes among Olmsted County, Minnesota, residents 1976-2009.

Figure 1

A. Age-specific incidence of ischemic colitis in males, females and together in both sexes among Olmsted County, Minnesota, residents 1976-09. B. Age-adjusted incidence rate of ischemic colitis in males, females and together in both sexes among Olmsted County, Minnesota, residents 1976-2009.

Figure 2

Overall survival of cases with ischemic colitis from the time of diagnosis in Olmsted County, Minnesota, 1976-2009 along their matched controls from time of index date.

Figure 3

Overall survival of cases with ischemic colitis from time of diagnosis and matched controls from index date in Olmsted County, Minnesota, 1976-2009 stratified by age groups: 3A, <40 years; 3B, 40-59 years; 3C, 60-79 years; and 3D, ≥80 years.