RESUMO
BACKGROUND: Israel has a high rate of Jewish immigration and a high prevalence of inflammatory bowel disease (IBD). AIM: To compare IBD prevalence in first-generation immigrants vs Israel-born Jews. METHODS: Patients with a diagnosis of IBD as of June 2020 were included from the validated epi-IIRN (Israeli IBD Research Nucleus) cohort that includes 98% of the Israeli population. We stratified the immigration cohort by IBD risk according to country of origin, time period of immigration, and age group as of June 2020. RESULTS: A total of 33544 patients were ascertained, of whom 18524 (55%) had Crohn's disease (CD) and 15020 (45%) had ulcerative colitis (UC); 28394 (85%) were Israel-born and 5150 (15%) were immigrants. UC was more prevalent in immigrants (2717; 53%) than in non-immigrants (12303, 43%, P < 0.001), especially in the < 1990 immigration period. After adjusting for age, longer duration in Israel was associated with a higher point prevalence rate in June 2020 (high-risk origin: Immigration < 1990: 645.9/100000, ≥ 1990: 613.2/100000, P = 0.043; intermediate/low-risk origin: < 1990: 540.5/100000, ≥ 1990: 192.0/100000, P < 0.001). The prevalence was higher in patients immigrating from countries with high risk for IBD (561.4/100000) than those originating from intermediate-/low-risk countries (514.3/100000; P < 0.001); non-immigrant prevalence was 528.9/100000. CONCLUSION: Lending support to the environmental effect on IBD etiology, we found that among immigrants to Israel, the prevalence of IBD increased with longer time since immigration, and was related to the risk of IBD in the country of origin. The UC rate was higher than that of CD only in those immigrating in earlier time periods.
RESUMO
BACKGROUND: There are currently no nationwide data on the epidemiology of inflammatory bowel diseases (IBD) in Israel. We aimed to determine the population-based epidemiological trends of IBD in the diverse Israeli population. METHODS: Health-administrative data were retrieved from all 4 Israeli health maintenance organizations, insuring 98% of the population, using validated identification algorithms. National trends were determined using Joinpoint regression analysis calculating annual percent change and average annual percent change (AAPC). RESULTS: By 2019, there were 46,074 patients with IBD in Israel, corresponding to a national prevalence of 519/100,000 (0.52%), of whom 54.1% had Crohn disease (CD) and 45.9% had ulcerative colitis (UC). The number of Jewish patients doubled from 18,701 in 2005 (354/100,000) to 38,950 (589/100,000) in 2018 (AAPC, +4.0%; P < 0.05), and the number of Arab patients increased 3-fold from 1096 (102.1/100,000) to 3534 (240.7/100,000; AAPC, +6.8%; P < 0.05) during the same years. However, the increase rate has gradually decelerated over time (annual percent change during 2005-2008, 2009-2014, and 2005-2018 was +6.7%, +4.2%, and +2.3%, respectively; P < 0.05). Pediatric prevalence increased from 37.4 to 52.2/100,000, with CD predominating in both Jews and Arabs. The incidence of CD remained stable (from 15.9/100,000 to 14.9/100,000) and the incidence of UC decreased (15.4/100,000 to 10.5/100,000 (AAPC, -3.2%; P < 0.001)). In contrast, pediatric incidence of CD increased from 7.3/100,000 to 8.3/100,000 (AAPC, +1.9%; P < 0.05) and that of UC increased from 2.6 to 4.4/100,000 (AAPC, +5.8%; P < 0.05). CONCLUSIONS: The IBD prevalence rate in Israel is still increasing but gradually decelerating, probably due to the decreasing overall IBD incidence. Nonetheless, incidence rate in children is still increasing. Ongoing narrowing in the rates between Jews and Arabs over time may indicate shared environmental factors.
