The association between new generation oral contraceptive pill and the development of inflammatory bowel diseases

BACKGROUND/AIMS: To examine the association between use of oral contraceptive pills (OCPs) and the risk of developing inflammatory bowel diseases (IBD), in a modern cohort. METHODS: A prospective nested case-control study across sites in the Asia-Pacific region was conducted; involving female IBD cases and asymptomatic controls. Subjects completed a questionnaire addressing questions related to OCP use. Primary outcome was the risk of development of IBD of those exposed to OCP versus non-exposure. Secondary outcomes were development of Crohn's disease (CD) versus ulcerative colitis (UC), and whether age of first use of OCP use may be associated with risk of IBD. RESULTS: Three hundred and forty-eight female IBD cases (41% CD, median age: 43 years) and 590 female age-matched controls were recruited. No significant association was found between OCP use and the risk of IBD (odds ratio [OR], 1.65; 95% confidence interval, 0.77–3.13; P=0.22), CD (OR, 1.55) or UC (OR, 1.01). The lack of association persisted when results were adjusted for age and smoking. IBD cases commenced OCP use at a younger age than controls (18 years vs. 20 years, P=0.049). CONCLUSIONS: In this large cohort of subjects from the Asia-Pacific region, we found a modest but not significantly increased risk of developing IBD amongst OCP users.

Changing epidemiological trends of inflammatory bowel disease in Asia

Inflammatory bowel disease (IBD) has become more common in Asia over the past few decades. The rate of increase in prevalence of the disease varies greatly in Asia, with several countries in East Asia experiencing a more than doubled increase in IBD prevalence over the past decade. Historically, ulcerative colitis (UC) is more common than Crohn's disease (CD) in Asia. However, a reverse trend is beginning to appear in more developed countries in Asia such as Japan, Korea, and Hong Kong. While Asian IBD patients share many similarities with their Western counterparts, there are important differences with significant clinical implications. In Asia, there are more men with CD, more ileo-colonic involvement in CD, less familial aggregation, fewer extra-intestinal manifestations and worse clinical outcomes for older-onset patients with UC. These differences are likely related to the different genetic makeup and environmental exposures in different regions. Evaluation of the differences and rates in epidemiologic trends may help researchers and clinicians estimate disease burden and understand the reasons behind these differences, which may hold the key to unravel the etiology of IBD.

Changing Epidemiology and Future Challenges of Inflammatory Bowel Disease in Asia

In the past decade, many countries in Asia, in particularly in East Asia, are experiencing a progressive rise in the incidence and prevalence of inflammatory bowel disease (IBD). Improved physician awareness and diagnostic methods are unlikely to fully account for this rapid increase. This epidemiological shift is likely to relate to industralization, westernization of lifestyles and changes in eating habits, as part of the socioeconomic development in Asia, although many of these putative environmental factors have not been formally investigated in Asian cohorts. Genetic factors for IBD differ between Asia and the West. NOD2/CARD15 mutation, repeatedly observed in the Caucasian populations, is not associated with Crohn's disease in Asian populations. Familial clustering is generally uncommon in Asia but it is expected to increase as the IBD prevalence in this region rises. Ethnic-racial differences of IBD have been described and Indians appear to be most affected in South-East Asia. Clinical manifestation of IBD in Asia resemble the Western population in general, but with some differences, including higher prevalence of males and ileocolonic disease, lower disease severity, surgical rates and extraintestinal manifestations. These differences may relate to time factor, genetic background and environmental factors. This review summarises recent epidemiological data of IBD including environmental factors associated with the development of IBD in Asia. Future research focusing on studying the epidemiology of IBD in an area of rapidly increasing prevalence such as Asia will allow the opportunity to identify potential risk factors and provide a better understanding of the aetiology of disease in the Asian population.

Changing Epidemiology and Future Challenges of Inflammatory Bowel Disease in Asia

In the past decade, many countries in Asia, in particularly in East Asia, are experiencing a progressive rise in the incidence and prevalence of inflammatory bowel disease (IBD). Improved physician awareness and diagnostic methods are unlikely to fully account for this rapid increase. This epidemiological shift is likely to relate to industralization, westernization of lifestyles and changes in eating habits, as part of the socioeconomic development in Asia, although many of these putative environmental factors have not been formally investigated in Asian cohorts. Genetic factors for IBD differ between Asia and the West. NOD2/CARD15 mutation, repeatedly observed in the Caucasian populations, is not associated with Crohn's disease in Asian populations. Familial clustering is generally uncommon in Asia but it is expected to increase as the IBD prevalence in this region rises. Ethnic-racial differences of IBD have been described and Indians appear to be most affected in South-East Asia. Clinical manifestation of IBD in Asia resemble the Western population in general, but with some differences, including higher prevalence of males and ileocolonic disease, lower disease severity, surgical rates and extraintestinal manifestations. These differences may relate to time factor, genetic background and environmental factors. This review summarises recent epidemiological data of IBD including environmental factors associated with the development of IBD in Asia. Future research focusing on studying the epidemiology of IBD in an area of rapidly increasing prevalence such as Asia will allow the opportunity to identify potential risk factors and provide a better understanding of the aetiology of disease in the Asian population.