Inflammatory bowel disease in the South Asian pediatric population of British Columbia

Environmental factors associated with Crohn's disease in India

BACKGROUND

The frequency of diagnosis of Crohn's disease (CD) in India is increasing. This case-control study was designed to detect associations of environmental and dietary factors with the diagnosis of CD.

METHODS

In 200 consecutive patients with CD and 200 control subjects without gastrointestinal disease, environmental hygiene exposures in childhood and in the past one year, and dietary preferences were recorded using a questionnaire. Univariate and multivariate analyses were done.

RESULTS

In univariate analysis, CD showed positive association with urban residence (at birth and current), availability of protected drinking water (childhood and current), availability of piped water in the house (childhood and current), and strict vegetarian dietary habit, and negative association with regular fish consumption and presence of cattle in the house compound. Multivariate analysis showed that regular fish consumption (OR 0.52, 95% CI 0.33-0.80, p = 0.003), and presence of cattle in the house compound currently (OR 0.57, 95% CI 0.35-0.92, p = 0.023) were significant protective associations, whereas use of safe drinking water was positively associated (OR 1.59, 95% CI 1.02-2.47, p = 0.042) with the disease.

CONCLUSION

Occurrence of CD was associated with dietary and environmental exposures, which indicate that diet and hygiene may influence the development of this disease.

Emigration to western industrialized countries: A risk factor for developing inflammatory bowel disease

BACKGROUND

A higher incidence of inflammatory bowel disease (IBD) in industrialized areas has been previously reported, but the effect of emigrating to western industrialized countries for a period of time and returning to the country of origin is unknown. Aim of the study was to evaluate the effect of emigrating to another country and returning to the place of origin on the risk of IBD.

METHODS

A prospective case-control study was performed. Inclusion criteria were all patients >18 years diagnosed with Crohn's disease (CD) or ulcerative colitis (UC) in the last 10 years. Healthy, unrelated controls, matched by sex, age and smoking habits, with no family history of IBD were included. All patients and controls were interviewed and emigration was defined as living for at least one year in another country.

RESULTS

242 consecutive patients with IBD (105 CD and 137 UC) and 242 controls were included. Patients who had previously emigrated developed more frequently IBD than controls (OR 1.93, 95%CI 1.19-3.15, p<0.01). Patients who emigrated to European countries developed more frequently IBD than controls (OR 1.91, 95%CI 1.07-3.47, p=0.02), but not those who had emigrated to Latin America (OR 1.48, 95%CI 0.67-3.27, p=0.32). Emigration plays a significant role in the development of UC (OR 2.24, 95%CI:1.29-3.88, p<0.01), but not in CD (OR 1.56, 95%IC:0.83-2.92, p=0.15).

CONCLUSIONS

People who emigrate to westernised countries have a higher risk for developing IBD, especially UC. Environmental factors related with industrialization seem to play an important role in the pathogenesis of these diseases.

A global perspective on gastrointestinal diseases

Common gastrointestinal diseases often exhibit geographic, cultural, and gender variations. Diseases previously less common in certain areas of the world have shown a recent increase in prevalence. Industrialization has traditionally been noted as a major cause for this epidemiologic evolution. However, environmental factors such as diet, hygiene, and exposure to infections may play a major role. Moreover, the way one disease presents in a certain location may vary significantly from the way it manifests in another culture or location. This article discusses global variations of inflammatory bowel disease, Helicobacter pylori, irritable bowel disease, fecal incontinence, hepatitis B, and hepatocellular cancer.

Diet in inflammatory bowel disease

The past few years have seen a great expansion of our understanding of the pathophysiology of inflammatory bowel disease (IBD). Much of the progress has been on the genetic basis of disease as well as the role of microbiota. These findings have magnified the role of the environmental component of this rather complex process. Recent advances have emanated from more in-depth, comprehensive, and at times nontraditional inquiry into the potential role of diet through its anti-inflammatory properties and modulation of microbiota. This concise review focuses on the novel aspects of research related to the potential role of diet in IBD.

Probiotics in inflammatory bowel diseases and associated conditions

A complex set of interactions between the human genes encoding innate protective functions and immune defenses and the environment of the intestinal mucosa with its microbiota is currently considered key to the pathogenesis of the chronic inflammatory bowel diseases (IBD). Probiotics offer a method to potentially alter the intestinal microbiome exogenously or may provide an option to deliver microbial metabolic products to alter the chronicity of intestinal mucosal inflammation characterizing IBD. At present, there is little evidence for the benefit of currently used probiotic microbes in Crohn's disease or associated conditions affecting extra-intestinal organs. However, clinical practice guidelines are now including a probiotic as an option for recurrent and relapsing antibiotic sensitive pouchitis and the use of probiotics in mild ulcerative colitis is provocative and suggests potential for benefit in select patients but concerns remain about proof from trials.

Ethnic variation in the annual rates of adult inflammatory bowel disease in hospitalized patients in Vancouver, British Columbia

BACKGROUND

There is currently little available information regarding the impact of ethnicity on the clinical features of inflammatory bowel disease (IBD). Migrating populations and changing demographics in Vancouver, British Columbia (BC) provide a unique opportunity to examine the role of ethnicity in the prevalence, expression and complications of IBD.

OBJECTIVES

To determine the demographics of IBD and its subtypes leading to hospitalization in the adult population of BC.

METHODS

A one-year retrospective study was performed for all patients who presented acutely with IBD to Vancouver General Hospital from January 1, 2006 to December 31, 2006. Data regarding sex, age, ethnicity, IBD type and extent of disease, complications and management strategies were collected. Clinical data were confirmed by pathology and radiology reports.

RESULTS

There were 186 cases of IBD comprising Crohn's disease (CD) 56%, ulcerative colitis (UC) 43% and indeterminate colitis (1%) 1%. The annual rate of IBD cases warranting hospitalization in Caucasians was 12.9 per 100,000 persons (7.9 per 100,000 persons for CD and 5.0 per 100,000 persons for UC). This was in contrast to the annual rate of IBD in South Asians at 7.7 per 100,000 persons (1.0 per 100,000 persons for CD and 6.8 per 100,000 persons for UC) and in Pacific Asians at 2.1 per 100,000 persons (1.3 per 100,000 persons for CD, 0.8 per 100,000 persons for UC). The male to female ratio was higher in South Asians and Pacific Asians than in Caucasians. The extent of disease was significantly different across racial groups, as was the rate of complications.

CONCLUSIONS

These early results suggest that there are ethnic disparities in the annual rates of IBD warranting hospitalization in the adult population of BC. There was a significantly higher rate of CD in the Caucasian population than in South Asian and Pacific Asian populations. The South Asian population had a higher rate of UC, with an increased rate of complications and male predominance. Interestingly, the rate of CD and UC was lowest in the Pacific Asian population. These racial differences - which were statistically significant - suggest a role for ethnodiversity and environmental changes in the prevalence of IBD in Vancouver.

Epidemiology of pediatric inflammatory bowel disease: a systematic review of international trends

BACKGROUND

Temporal trends in the incidence of pediatric-onset inflammatory bowel disease (IBD) are controversial and a wide range of estimates have been reported worldwide. We conducted a systematic review of research describing the epidemiology of childhood-onset IBD to assess changes in incidence rates over time and to evaluate international differences.

METHODS

The following electronic databases were searched for articles published 1950-2009: MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Cochrane IBD/Functional Bowel Disorders Group Specialised Trial Register. All included studies reported incidence or prevalence of IBD, Crohn's disease (CD) or ulcerative colitis (UC). Two authors independently completed the data extraction form for each eligible study. Choropleth maps demonstrated the international incidence of IBD, CD, and UC. Incidence of CD and UC was graphed using data from studies reporting rates in multiple time periods.

RESULTS

The search yielded 2209 references and review resulted in 139 included studies from 32 countries. A wide range of incidence was reported internationally; however, rates of IBD were not described in most countries. Twenty-eight studies (20.1%) used statistical analysis to assess trends over time, and 77.8% reported statistically significantly increased incidence of pediatric IBD. Of studies calculating statistical trends in CD incidence, 60% reported significantly increased incidence. Of similar UC studies, 20% reported significantly increased incidence.

CONCLUSIONS

Globally rising rates of pediatric IBD (due primarily to the rising incidence of CD) was demonstrated in both developed and developing nations; however, most countries lack accurate estimates. Analyzing incidence trends may help identify specific environmental and genetic risk factors for pediatric IBD.

Epidemiologic clues to inflammatory bowel disease

In this article, the recent literature exploring the epidemiology of inflammatory bowel disease (IBD) is reviewed. Epidemiologic studies present data on disease burden, but may also provide clues to disease etiology. The emergence of IBD in developing nations warrants a systematic search for environmental changes in those countries to explain the evolution of IBD. The hygiene hypothesis suggests that an alteration in the microbial environment experienced by the host facilitates the evolution of chronic immune-mediated diseases. One complex database study suggested that areas with high species richness of human intestinal helminthes are areas with genetic changes in interleukin gene loci. In other words, over the years, the microbial ecology has affected human genetics, which in turn would have an impact on immune responses. Other factors affect the gut microbiome, and several studies have explored the increase in incidence of IBD in relation to such factors as exogenous infections, use of antibiotics, and diet.

Perinatal lipid nutrition alters early intestinal development and programs the response to experimental colitis in young adult rats

The long-chain polyunsaturated n-6 and n-3 fatty acids are essential nutrients in membrane biogenesis and regulate gene expression via their eicosanoid metabolites. We investigated whether the n-6 and n-3 fatty acid supply as determined by maternal diet alters colonic phospholipid fatty acids, intestinal morphology, and epithelial barrier permeability during milk feeding with lasting effect on mucosal responsiveness to dinitrobenzene sulfonic acid (DNBS)-induced colitis in young adulthood. Female rats were fed diets with 20% energy from safflower oil (SO) or canola oil (CO), or 8% fish oil (FO) plus 2% SO (10% FO) or 18% FO plus 2% SO (20% FO) throughout gestation and lactation and offspring weaned to a standard diet at 21 days of age. At 15 days of age, pups in the 20% and 10% FO groups had lower 20:4n-6 and higher 20:5n-3 and 22:6n-3 in colon phospholipids (P < 0.01), shorter crypts (P < 0.05), and higher paracellular permeability than SO or CO groups. At 3 mo of age, male offspring in the FO groups showed lasting reduction of crypt depth and a heightened inflammatory response to DNBS. We demonstrate that early decreased colon 20:4n-6 with increased n-3 fatty acids impairs intestinal barrier development and sensitizes the colon response to inflammatory insults later in life.

Characteristics and trends in the incidence of inflammatory bowel disease in Korean children: a single-center experience

BACKGROUND

Inflammatory bowel disease (IBD) is rare in Asian children and few reports on pediatric IBD have appeared.

AIMS

We, therefore, investigated the incidence trends and clinical characteristics of pediatric IBD in Korea.

METHODS

We enrolled 48 children with Crohn's disease (CD) and 14 children with ulcerative colitis (UC) from 1996 to 2007. Trends in annual enrollment and clinical characteristics were retrospectively evaluated by medical record review.

RESULTS

During the 12 years of observation, the number of new enrollments gradually increased. CD showed male predominance (33 boys, 15 girls), but more females presented with UC (4 boys, 10 girls). A relevant family history was observed in 3 (4.9%) of the 61 unrelated families. The most common presenting symptom was abdominal pain (67%) in CD and hematochezia (93%) in UC. Growth delay was observed in 10% of CD patients, but not in any of the UC patients. In CD, colonic involvement occurred in 87% of patients, ileal involvement in 87%, and both the small bowel and colon were affected in 75%. With UC, pancolitis occurred in 43% of patients, left-sided colitis in 36%, and proctitis in 21%, including all three patients with appendiceal orifice inflammation. The most frequent disease behavior was inflammatory in 85% of patients, but perianal fistula was noted in 50% of CD patients.

CONCLUSION

This study showed that the incidence of pediatric IBD has been rapidly increasing in Korea in recent years. Relevant family history is less prevalent and phenotypic expression differs from what is seen in Western countries.

The future of molecular approaches to inflammatory bowel disease

Technological advances in genomics and transcriptomics have resulted in the introduction of molecular tests into the clinical arena. Despite established uses of such tests in the oncology field, their integration into the management of complex diseases has not been widely evaluated. Progress in the field of inflammatory bowel disease (IBD) genetics has been rapid in recent years, and these advances have provided more urgent impetus to investigating the role of molecular tests in IBD. This article summarizes the current state of molecular testing available for IBD, and the potential utility of such tests as research in the area widens.

The geoepidemiology of autoimmune intestinal diseases

Inflammatory bowel diseases (IBD) are chronic diseases of the intestinal tract which principally are composed of ulcerative colitis (UC) and Crohn's disease (CD). The prevalence and incidence of both forms of IBD have historically been higher in developed countries with decreasing North-South gradient. However, more recent evidence demonstrate changing demographics as countries become more developed and immigration increases from underdeveloped countries to developed countries. Typically these changes are marked by an increase in ulcerative colitis followed by an increase in CD. Thus, most if not all human populations appear to be susceptible to IBD under certain environmental influences. Several hypothesis have been advanced to explain these changing demographics including alterations in the bowel microflora, but direct experimental evidence is lacking in most cases. Celiac disease or gluten-sensitive enteropathy is a related inflammatory condition which is induced in susceptible individuals when exposed to gluten-containing foods. Similarly, the prevalence of celiac disease is increasing as the consumption of gluten-containing foods is increasing worldwide.

The incidence of inflammatory bowel disease in the pediatric population of Southwestern Ontario

PURPOSE

Despite a rising worldwide incidence of inflammatory bowel disease (IBD), few data exist on Canadian children. We reviewed the incidence of IBD in all children 17 years or younger in Southwestern Ontario.

MATERIALS AND METHODS

A chart review from 1997 to 2006 revealed 123 children with IBD. Patients were divided into 2 groups according to year of diagnosis: group 1 = 1997 to 2001 and group 2 = 2002 to 2006. Our catchment population was determined from census data.

RESULTS

Sex (group 1 = 52% females; group 2 = 45% females, P = .42) and age (group 1 = 12.4 +/- 3.6 years; group 2 = 12.9 +/- 3.5 years; P = .43) were similar between groups. Although the overall incidence of IBD decreased (group 1 = 14.3 cases/100,000; group 2 = 12.4 cases/100,000), the incidence of Crohn's disease nearly doubled (group 1 = 3.5 cases/100,000; group 2 = 6.01 cases/100,000) while the incidence of ulcerative colitis decreased substantially (group 1 = 10.6 cases/100,000; group 2 = 6.01 cases/100,000). The incidence of indeterminate colitis was 0.2 cases/100,000 for group 1 and 0.4 cases/100,000 for group 2. The rate of surgical intervention decreased over time, with 43% of patients requiring surgery in group 1 and 31% in group 2 (P = .17).

CONCLUSION

Despite a slight decrease in pediatric IBD incidence in Southwestern Ontario, the incidence of Crohn's disease has nearly doubled over the last decade. Reasons for this remain unclear, although given the relatively short time interval, environmental factors, rather than genetic changes, seem more likely.

Advances in epidemiology and diagnosis of inflammatory bowel diseases

The etiology of chronic inflammatory bowel diseases (IBD) remains unknown. Understanding IBD epidemiology helps to identify at-risk individuals, to appreciate the changing demographic profile of IBD, and to interpret theories of IBD pathogenesis. This article reviews recent advances in epidemiology and diagnostics. The importance of Clostridium difficile is highlighted. State-of-the-art IBD diagnostic modalities include serology, fecal markers, and advanced radiologic or endoscopic techniques. These include wireless capsule endoscopy, balloon enteroscopy, chromoendoscopy, high-magnification endoscopy, and MRI. The increasing number of available modalities requires appreciation of their indications, strengths, and limitations. This article discusses these issues relevant to the clinician.

Inflammatory bowel disease: a survey of the epidemiology in Asia

Inflammatory bowel disease (IBD) has long been considered a disease that affects predominantly a Western population. The incidence and prevalence rates from Asian populations are much lower in comparison. More recent data, however, have shown significantly higher rates in Asians and time trend studies have shown an increase in the incidence of ulcerative colitis (UC) and a similar but lower rise in Crohn's disease (CD). The epidemiological changes that are taking place mirror that of the Western experience seen 50 years previously and seem to occur in parallel with the rapid socioeconomic development taking place in Asia. It appears that certain racial groups are more prone than others to develop IBD. For instance, Indians in South-East Asia have higher rates compared to Chinese and Malays. While there is host genetic predisposition, environmental factor(s) may be responsible for this difference. Migrant studies of South Asians in the UK, where second-generation immigrants have assumed incidence rates as high as the indigenous whites and Asian Jews who develop high incidence rates comparable to Jews from Europe or North America in Israel point to the role of environmental factors. It is unclear which specific factors are responsible. Studies have suggested a change in diet to a more Westernized one may underlie this epidemiological change in the Asian population. It is likely that there are racial groups amongst Asians who are more susceptible to IBD and who will demonstrate a higher frequency of IBD when exposed to putative environmental factors.

An update on the epidemiology of inflammatory bowel disease in Asia

A rising trend in the incidence and prevalence of inflammatory bowel disease (IBD) in Asia has been recognized for the past two decades. It has been postulated that this phenomenon may be related to the westernization of lifestyles, including changes in dietary habits and environmental changes such as improved sanitation and industrialization. Previously we reported that the incidence and prevalence rates of IBD in Asia were low compared with the West, but there was a notably rising secular trend. In this review, we summarize the recent epidemiological data in Asia, characterize the clinical features, risk factors and genetic susceptibility of Asian IBD patients, and compare these to those of Western IBD patients. In the past decade, the incidence and prevalence of IBD reported across Asia, particularly in East Asia, has continued to increase. Familial clustering is generally uncommon in East Asia but appears to be higher in West Asia. The genetic susceptibilities in Asian IBD patients differ from those of White patients, as NOD2/CARD15 mutations are much less common. The clinical phenotypes and complication rates of Asian IBD resemble the White population in general, but with some differences, including lower surgical rates, higher prevalence of males, and higher prevalence of ileocolonic involvement among East Asian Crohn's disease patients, and a low frequency of primary sclerosing cholangitis among IBD patients in East and Southeast Asia.

Dietary lipids in early development and intestinal inflammatory disease

Inflammatory bowel diseases are life-long reoccurring inflammatory disorders of the gastrointestinal tract and have been increasing in incidence in recent decades, notably in the pediatric population. Although genetic predisposition remains an important factor, this increased incidence most likely reflects an environmental change. One potential contributor to this is the change in dietary fat intake, with dietary intake of n-6 polyunsaturated fatty acids (PUFAs) following a similar temporal pattern to the change in inflammatory bowel disease incidence. Dietary n-6 PUFAs comprise a major, modifiable, environmental factor known to promote a heightened inflammatory response through a number of pathways, including their role as precursors for synthesis of eicosanoids and their inhibitory effect on the synthesis of the n-3 PUFAs eicosapentanoic acid and docosahexanoic acid. The increase in n-6 PUFA intake affects individuals of all ages, with fetal PUFA accretion and infant dietary PUFA intake from breast milk reflecting maternal dietary intake. A high level of n-6 PUFA in milk results in increased n-6 PUFA in colonic phospholipids and an exaggerated inflammatory response to chemically induced colitis. Conversely, during development, a diet low in n-6 PUFAs and high in n-3 PUFAs increases colonic n-3 fatty acids, attenuates the inflammatory response, and lowers colonic damage. High dietary n-6 PUFA intake may be an important environmental modifier that contributes to inflammatory bowel diseases.