METHODS: The patients studied consisted of 58 people with an established diagnosis of ulcerative colitis (UC) and Crohn's disease (CD) as determined by a combination of clinical, radiological, endoscopic and histological criteria. The patients were residents of a well-defined geographical area in the northern part of Singapore and had been referred to the single regional hospital. Epidemiological data including sex, age, ethnicity, family history and disease type and extent were collected from case records and patient interviews.
RESULTS: There were 37 UC and 21 CD patients. Of the patients with UC, 67.5% were Chinese, 13.5% were Malay and 19% were Indian. The CD group consisted of 81% Chinese, 9.5% Malay and 9.5% Indian patients. The study population from which the patients were drawn was approximately 0.5 million in size.
CONCLUSIONS: The overall prevalence of UC was 6 per 100,000 and of CD was 3.6 per 100,000 in Singapore. There were disproportionately more Indians suffering from UC, with a prevalence of 16.2 per 100,000 in comparison with six per 100,000 for Chinese and seven per 100 000 for Malays. The relative risk of UC in Indians is 2.9-fold greater than for the Chinese (CI= 1.25-6.7) which was statistically significant. This trend was not seen for CD.
METHODS: Data were obtained retrospectively from a review of the medical records of in- and out-patients with a diagnosis of UC at the University Hospital, Kuala Lumpur between 1985 and 1998.
RESULTS: There were 45 confirmed cases of UC of which 3 were foreigners, who were excluded from analysis. Thirty new cases of UC were diagnosed during the study period. Their mean age at presentation was 33.0+/-10.0 years. The highest prevalence of UC was 17.9/100 000 hospital admissions in the Indians, followed by 11.2/100 000 hospital admissions in the Chinese. The lowest prevalence was 3.7/100 000 hospital admissions in the Malays. The prevalence of UC was significantly higher in the Indians and the Chinese when compared with the Malays with an OR of 4.89 (CI = 2.02-12.24; chi2 = 15.45, P<0.001) and 3.06 (CI = 1.24-7.78; chi2 = 6.30; P = 0.012) respectively. The extent of colonic disease was similar in the Malay and Indian patients. In contrast, distal or left-sided colitis predominated in the Chinese with an OR of 8.17 (95%CI = 1.31-64.87; chi2 = 5.53, P = 0.02). Extraintestinal manifestations were uncommon (11.9%).
CONCLUSION: UC is an uncommon disease in Malaysia, but racial differences exist. The Indians had the highest prevalence of UC with the Chinese demonstrating the least extensive disease.