Familial occurrence of inflammatory bowel disease in Korea.
BACKGROUND
Little information is available about the familial aggregation of inflammatory bowel disease (IBD) in Asian populations. We therefore determined the risk of familial aggregation of IBD among first-degree relatives of patients with ulcerative colitis (UC) or Crohn's disease (CD) in an ethnically distinct Korean population.


METHODS
Familial aggregation of IBD was evaluated in terms of family history, prevalence, lifetime risk, and population relative risk in first-degree relatives of 1440 unrelated patients with UC (n = 1043) or CD (n = 397).


RESULTS
A positive first-degree family history of IBD was observed in 27 probands (1.88%): 21 of 1043 (2.01%) with UC and 6 of 397 (1.51%) with CD. The crude prevalence of IBD in first-degree relatives of probands with IBD was 0.31%. The lifetime risk of IBD was 0.54% in all first-degree relatives of IBD probands, 0.52% in UC probands, and 0.67% in CD probands, with overall lifetime relative risks of 0.12% in parents, 0.79% in siblings, and 1.43% in offspring. The age- and sex-adjusted population relative risk of IBD was 13.8 in first-degree relatives of probands with IBD.


CONCLUSIONS
Although a positive family history, prevalence, and lifetime risk of IBD among first-degree relatives of Korean IBD patients are much lower than among relatives of Western patients, the population relative risk in first-degree relatives is about equal in Koreans and Westerners. This finding indicates that a positive family history is an important risk factor for IBD in Koreans and in Westerners.
Park
Jong Beom
JB
Departments of Internal Medicine and Surgery, Song Do Colorectal Hospital, University of Ulsan College of Medicine, Asan Medical Center, Seoul 138-736, Korea.
Yang
Suk-Kyun
SK
Byeon
Jeong-Sik
JS
Park
Eui-Ryun
ER
Moon
Gyoo
G
Myung
Seung Jae
SJ
Park
Won Kap
WK
Yoon
Seo Gue
SG
Kim
Hyun Shig
HS
Lee
Jong Gyun
JG
Kim
Jin Ho
JH
Il Min
Young
Y
Kim
Kwang Yeon
KY
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D003710:Demography; D005192:Family Health; D005260:Female; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000453:epidemiology*; D007723:Korea / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D018570:Risk Assessment