Objectives: To study the incidence of inflammatory bowel disease (IBD) in the health district of Mérida (Spain).
Material and methods: Retrospective hospital study of all patients diagnosed with IBD between 1/1/96 and 31/12/00 in the Hospital de Mérida, which is the reference center for a population of 158,407 inhabitants. Overall rates, standard rates based on the standard European population at 10-year age intervals, and accumulated rates were calculated. The standard error of these rates was calculated to establish a 95% confidence interval.
Results: In the five years analyzed, 54 new cases of IBD were observed. Of these, there were 39 cases of ulcerative colitis (UC) with a sex distribution of 24 men (61.6%) and 15 women (38.4%), and 15 cases of Crohn's disease (CD) in seven men (46.7%) and eight women (53.3%). The mean age at diagnosis was 47.2 years for UC and 40.8 years for CD. In UC, involvement was as follows: proctitis in eight patients (20.5%), proctosigmoiditis in three (7.7%), left colon in 18 (46.1%), transverse colon in four (10.3%) and entire colon in six (15.4%). In CD, the following distribution was found: small intestine in six patients (40%), ileocolic in five (33.3%) and colic in four (26.7%). The incidence rates adjusted for age (15-64 years) and sex and expressed in cases/100,000 inhabitants were as follows: UC: 9.57 (95% CI, 0-16.3) for men and 2.09 (95% CI, 0-5.44) for women; CD: 3.15 (95% CI, 0-7.27) for men and 1.16 (95% CI, 0-3.52) for women.