Authors: Bjornsson S, Johannsson JH, Oddsson E.

Institution: Dept. of Medicine, Reykjavik Hospital, Iceland.

Background: A previous nationwide epidemiologic study of inflammatory bowel disease (IBD) in Iceland in 1950-79 showed a low but steadily rising incidence. The incidence of IBD in Iceland in 1980-89 was investigated and compared with reports from neighboring countries.

Results: The mean annual incidence of ulcerative colitis (UC) was 11.7/100,000, and that of CD 3.1/100,000. The highest age-specific incidence of UC was in the group 30-39 years old and for CD in the group 60-69 years old. The most frequent involvement at diagnosis of UC was proctitis only, in 54%, and in CD colon only, in 54.7% of the patients.

Conclusions: This study shows a continuing increase in the incidence of both diseases. Compared with the period 1970-79, there has been an almost twofold increase in the mean annual incidence of UC and more than a threefold increase of CD, a statistically significant increase in both instances.

Study link: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=9489911&query_hl=11

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