Prevalence of inflammatory bowel disease in an insured population in Puerto Rico during 1996

Limited data exists about Inflammatory Bowel Disease (IBD) in Hispanic populations. The aims of the present study were to estimate overall and specific prevalence of IBD (Crohn's disease and ulcerative colitis) and to describe the characteristics of a group of patients from the University of Puerto Rico's IBD Registry.

To estimate the prevalence of IBD, computerized records of all physician billing and hospital discharges from a major health insurer in Puerto Rico and classified with ICD-9-CM codes 555.0-555.9 (Crohn's disease) and 556.0-556.9 (ulcerative colitis) during 1996 were searched. Prevalence was estimated by age group, sex, and type of insurance. To describe demographic and selected clinical information from patients with IBD, data gathered in the University of Puerto Rico's IBD Registry from 1995 through 2000 was analyzed.

Out of 802,726 insured individuals, 332 had a diagnosis of Crohn's disease, 499 of ulcerative colitis and 21 had both diagnoses. The estimated prevalence per 100,000 was 41.4 for Crohn's disease, 62.2 for ulcerative colitis, and 106.1 cases per 100,000 for IBD. Peak prevalence of Crohn's disease occurred among the age groups 50-59 years and > or = 60 years, and the overall female:male prevalence ratio of Crohn's disease was 1.13 (95% CI: 0.91-1.42). Ulcerative colitis was most prevalent among insured individuals aged 50-59 years and 40-49 years. The prevalence of ulcerative colitis was significantly higher among females than among males, with an overall prevalence ratio of 1.42 (95% CI: 1.18-1.71). Of 342 patients participating in the IBD Registry, 155 (45.3%) had Crohn's disease and 187 (54.7%) had ulcerative colitis. Among patients diagnosed with Crohn's disease, 51.6% were females, the mean age was 35.2 +/- 18.3 years, and 18.1% had a family history of IBD. More than half (57.8%) of patients with ulcerative colitis were females, the mean age was 42.6 +/- 17 years, and 17.1% had a family history of IBD.

The estimated prevalence of IBD in this insured population in Puerto Rico places it among the middle-range of that reported for other countries. Additional studies must be conducted in Puerto Rico in order to confirm the observed findings. Population-based epidemiologic studies aimed at estimating the burden of IBD in Hispanic populations in the United States and Latin America are essential for health care planning.