10 The present review aimed to study the epidemiology of IBDs in Iran in comparison to Asian countries. There have been several epidemiologic studies on IBDs in Iran with respect to such variables as age, gender, family history, common risk factors (e.g. genetics, family aggregation, appendectomy, and smoking), less common risk factors, and clinical features. In each section of this Inhibitors,research,lifescience,medical review, data on IBDs Iran will be compared with those in Asian countries. Materials and Methods PubMed, Medline, and Persian databases-including SID and IranMedex were searched from 1970 to 2012. The keywords used
in this search were inflammatory bowel Inhibitors,research,lifescience,medical disease, Iran, ulcerative colitis, Crohn’s disease, epidemiology, risk factors, genetics,
extra-intestinal manifestations, Asia, Middle East, and ethnicity. OR, AND or NOT were applied during search by MeSH, appropriately. Due to restrictions, only the Persian and English languages were used as limitation (Persian for references in Iran). Only the epidemiological aspects assessed in Iranian articles Inhibitors,research,lifescience,medical were compared with the same subjects in other Asian countries. Articles in the form of clinical trials, case reports, case series, and radiologic and surgical procedures were excluded. Each article was surveyed twice by two authors, and the obtained data were Inhibitors,research,lifescience,medical recorded in a pre-prepared checklist. Of all the articles on the subject in Iran (available in above indices), two were duplicated and just one was used in the present study. Asian countries
were defined according to the latest confirmed map by the United Nations (UN) (United Nations Statistics Division, 2011). Among the articles, only those review articles whose references were used in our references were selected in order to complete our reference list.10 In total, there were 21 documented articles on IBD epidemiology in Iran and 170 in Asia. The articles will be described in the following section (figure 1). Figure 1 This Inhibitors,research,lifescience,medical flow chart depicts the inclusion and exclusion criteria applied in the present review Incidence and Prevalence According to a recent systematic Cell press review that has assessed the trend of incidence and prevalence of IBDs around the world, the incidence and prevalence rates of IBDs have increased in the last 4-5 decades. The annual incidence rates were 0.6-24.3, 0.1-6.3, and 0-19.2 per 100,000 BYL719 chemical structure individuals for UC and 0.3-12.7, 0.04-5.0, and 0-20.2 per 100,000 individuals for CD in Europe, Asia and Middle East, and North America-respectively. Also, the prevalence ranges were 4.9-505, 4.9-168.3, and 37.5-248.6 per 100,000 persons for UC and 0.6-322, 0.88-67.9, and 16.7-318.5 per 100,000 persons for CD in Europe, Asia and Middle East, and North America-respectively.