Epidemiological trends and geographic variation in hospital admissions for diverticulitis in the United States

Abstract

To characterize the increasing incidence and geographic variation of acute diverticulitis. Using the nationwide inpatient sample (NIS) we identified a cohort who had been admitted with diverticulitis between 1998 and 2005. We calculated age-, sex-, and region-specific rates of hospitalizations for diverticulitis over time. The age-adjusted hospitalization rate for diverticulitis increased from 61.8 per 100,000 to 75.5 per 100,000 between 1998 and 2005, and increased similarly in both sexes. Diverticulitis-associated admissions were male-predominant in those younger than age 45 years but were female-predominant thereafter. Admission rates increased the most among those < 45 years, while remaining unchanged for those ≥ 65 years. By 2005, the majority of hospitalized patients were < 65 years. Age-adjusted rates of diverticulitis-associated hospitalizations were lower in the West (50.4/100,000) compared to the Northeast (77.7/100,000), South (73.9/100,000), and Midwest (71.0/100,000). Diverticulitis-associated hospitalizations have steeply risen, especially in young adults. These epidemiological trends vary by geographic region and warrant further investigation into potential dietary and environmental etiologies.