Inflammatory bowel diseases among first-generation and second-generation immigrants in Denmark: a population-based cohort study

OBJECTIVE

Our objective was to estimate the relative risk of IBD among first-generation and second-generation immigrants in Denmark compared with native Danes.

DESIGN

Using national registries, we established a cohort of Danish residents between 1977 and 2018. Cohort members with known country of birth were followed for Crohn's disease (CD) and ulcerative colitis (UC) diagnoses. Incidence rate ratios (IRRs) served as measures of relative risk and were calculated by log-linear Poisson regression, using rates among native Danes as reference, stratified by IBD risk in parental country of birth, and among first-generation immigrants by age at immigration and duration of stay in Denmark.

RESULTS

Among 8.7 million Danes, 4156 first-generation and 898 second-generation immigrants were diagnosed with CD or UC. Overall, comparing first-generation immigrants with native Danes, the IRR was 0.80 (95% CI 0.76 to 0.84) for CD and 0.74 (95% CI 0.71 to 0.77) for UC. The IRR of IBD increased with ≥20 years stay in Denmark. The IRR of CD increased with immigration at ≥40 years of age. Comparing second-generation immigrants with native Danes, the IRR of IBD was 0.97 (95% CI 0.91 to 1.04). There was significant interaction with sex, with higher IRR of IBD in male than in female immigrants.

CONCLUSION

Relative to native Danish men and women, IBD risk among first-generation immigrants was lower, reflected the risk in their parental country of birth and increased with ≥20 years stay in Denmark. For second-generation immigrants, relative risk of IBD was lower only among women. These complex patterns suggest the role of environmental IBD risk factors.

Common and Rare Variant Prediction and Penetrance of IBD in a Large, Multi-ethnic, Health System-based Biobank Cohort

BACKGROUND AND AIMS

Polygenic risk scores (PRS) may soon be used to predict inflammatory bowel disease (IBD) risk in prevention efforts. We leveraged exome-sequence and single nucleotide polymorphism (SNP) array data from 29,358 individuals in the multiethnic, randomly ascertained health system-based BioMe biobank to define effects of common and rare IBD variants on disease prediction and pathophysiology.

METHODS

PRS were calculated from European, African American, and Ashkenazi Jewish (AJ) reference case-control studies, and a meta-GWAS run using all three association datasets. PRS were then combined using regression to assess which combination of scores best predicted IBD status in European, AJ, Hispanic, and African American cohorts in BioMe. Additionally, rare variants were assessed in genes associated with very early-onset IBD (VEO-IBD), by estimating genetic penetrance in each BioMe population.

RESULTS

Combining risk scores based on association data from distinct ancestral populations improved IBD prediction for every population in BioMe and significantly improved prediction among European ancestry UK Biobank individuals. Lower predictive power for non-Europeans was observed, reflecting in part substantially lower African IBD case-control reference sizes. We replicated associations for two VEO-IBD genes, ADAM17 and LRBA, with high dominant model penetrance in BioMe. Autosomal recessive LRBA risk alleles are associated with severe, early-onset autoimmunity; we show that heterozygous carriage of an African-predominant LRBA protein-altering allele is associated with significantly decreased LRBA and CTLA-4 expression with T-cell activation.

CONCLUSIONS

Greater genetic diversity in African populations improves prediction across populations, and generalizes some VEO-IBD genes. Increasing African American IBD case-collections should be prioritized to reduce health disparities and enhance pathophysiological insight.

Inflammatory polyps occur more frequently in inflammatory bowel disease than other colitis patients

BACKGROUND

Colitis is generally considered a risk factor for colon neoplasia. However, not all types of colitis seem to have equal neoplastic transformation potential.

AIM

To determine the prevalence of colorectal polyps in a predominantly African American population with inflammatory bowel disease (IBD) and Non-IBD/Non-Infectious Colitis (NIC).

METHODS

We retrospectively evaluated medical records of 1060 patients previously identified with colitis at Howard University Hospital, based on ICD-10 code. Among these, 485 patients were included in the study: 70 IBD and 415 NIC based on a thorough review of colonoscopy, pathology and clinical reports. Logistic regression analysis was applied to estimate the risk of polyps in patients with IBD compared to those with NIC after adjusting for age and sex. A subgroup analysis within the IBD group was performed.

RESULTS

Of the 485 patients, 415 were NIC and 70 were IBD. Seventy-three percent of the NIC patients and 81% of the IBD patients were African Americans. Forty six percent of IBD and 41% of NIC cases were male. IBD patients were younger than NIC patients (median age of 38 years vs. 50, P < 0.001). The prevalence of all types of polyps was 15.7 and 8.2% in the IBD and NIC groups, respectively (P = 0.045). Among patients with polyps, the prevalence of inflammatory polyps was higher in the IBD group (55%) compared to the NIC group (12%). After adjusting for age, sex and race, odds ratio of inflammatory polyps in IBD patients was 6.0 (P = 0.016). Adenoma prevalence was 4.3% (3/70) in IBD patients and 3.9% (16/415) in the NIC patients (p = 0.75). The anatomic distribution of lesions and colitis shows that polyps occur predominantly in the colitis field regardless of colitis type. More polyps were present in the ulcerative colitis patients when compared to Crohn's disease patients (27% vs. 5%, P < 0.001) within the IBD group.

CONCLUSION

Our study shows that inflammatory polyps are more common in IBD patients when compared to NIC patients. Most polyps were in the same location as the colitis.

Ethnic differences in inflammatory bowel disease: Results from the United Kingdom inception cohort epidemiology study

BACKGROUND

The current epidemiology of inflammatory bowel disease (IBD) in the multi-ethnic United Kingdom is unknown. The last incidence study in the United Kingdom was carried out over 20 years ago.

AIM

To describe the incidence and phenotype of IBD and distribution within ethnic groups.

METHODS

Adult patients (> 16 years) with newly diagnosed IBD (fulfilling Copenhagen diagnostic criteria) were prospectively recruited over one year in 5 urban catchment areas with high South Asian population. Patient demographics, ethnic codes, disease phenotype (Montreal classification), disease activity and treatment within 3 months of diagnosis were recorded onto the Epicom database.

RESULTS

Across a population of 2271406 adults, 339 adult patients were diagnosed with IBD over one year: 218 with ulcerative colitis (UC, 64.3%), 115 with Crohn's disease (CD, 33.9%) and 6 with IBD unclassified (1.8%). The crude incidence of IBD, UC and CD was 17.0/100000, 11.3/100000 and 5.3/100000 respectively. The age adjusted incidence of IBD and UC were significantly higher in the Indian group (25.2/100000 and 20.5/100000) compared to White European (14.9/100000, P = 0.009 and 8.2/100000, P < 0.001) and Pakistani groups (14.9/100000, P = 0.001 and 11.2/100000, P = 0.007). The Indian group were significantly more likely to have extensive disease than White Europeans (52.7% vs 41.7%, P = 0.031). There was no significant difference in time to diagnosis, disease activity and treatment.

CONCLUSION

This is the only prospective study to report the incidence of IBD in an ethnically diverse United Kingdom population. The Indian ethnic group showed the highest age-adjusted incidence of UC (20.5/100000). Further studies on dietary, microbial and metabolic factors that might explain these findings in UC are underway.

A comparison of the risk of postoperative recurrence between African-American and Caucasian patients with Crohn's disease

BACKGROUND

Many patients with Crohn's disease will develop complications that require surgery. Recurrence after surgery is common.

AIM

To assess racial differences in postoperative recurrence between African-Americans and Caucasians.

METHODS

Medical records of Crohn's disease patients who underwent surgery (ileal, colonic, or ileocolonic resection) between June 2014 and June 2016 were reviewed. The primary endpoints were clinical and endoscopic remission at 6-12 months after a Crohn's disease surgery. Secondary outcomes included biological and histologic remission. Risks of recurrence were assessed by univariate, multivariate, and propensity score-matched analysis.

RESULTS

Thirty-six African-American and 167 Caucasian patients with Crohn's disease were included for analysis. There was no difference in disease location, disease behaviour, type of surgery performed, and pre- or postoperative medication use between the two groups. The rate of endoscopic remission did not differ between African-American and Caucasian patients (50% vs 42%, P = 0.76), and race did not influence the risk of endoscopic recurrence on univariate, multivariate, or propensity score-matched analysis. The rate of clinical remission was significantly lower in African-American patients compared to Caucasian patients (36% vs. 63%, P = 0.008). African-American race was significantly associated with clinical recurrence on univariate (odds ratio (OR) 6.76, 95% CI 1.50-30.40; P = 0.01), multivariate (OR 5.02, 95% CI 1.60-15.80; P = 0.006), and propensity-matched analysis (68% vs. 32% in Caucasians, P = 0.005). Rates of biologic and histologic remission were similar between the two groups on all analyses.

CONCLUSIONS

We found that African-American patients with Crohn's disease have a similar degree of objective measures of mucosal inflammation after surgery including endoscopic recurrence as compared to Caucasian patients. However, African-American race was significantly associated with clinical recurrence, suggesting the presence of ethnic variation in postoperative presentation in Crohn's disease.

Association between the functional PTPN22 G788A (R263Q) polymorphism and susceptibility to autoimmune diseases: A meta-analysis

This study explored whether the functional protein tyrosine phosphatase nonreceptor 22 (PTPN22) G788A (R263Q) polymorphism is associated with susceptibility to autoimmune diseases. A meta-analysis was conducted using 23 comparative studies with a total of 16,719 patients and 17,783 controls. The meta-analysis showed an association between the A allele of the PTPN22 G788A polymorphism and decreased risk of autoimmune diseases in all subjects (p &lt; 0.001). Analysis after stratification by ethnicity indicated that the PTPN22 788A allele was significantly associated with autoimmune diseases in Europeans (p &lt; 0.001) but not in Latin Americans. Meta-analysis by autoimmune disease type showed a significant negative association between the PTPN22 788A allele and systemic lupus erythematous (SLE) (p = 001), rheumatoid arthritis (RA) (p = 0.008), ulcerative colitis (UC) (p = 0.016), but not Crohn's disease (CD). A single study for each showed no association between the PTPN22 788A allele and systemic sclerosis, giant cell arteritis, Henoch-schonlein purpura, uveitis, and Grave's disease. This meta-analysis demonstrates that the PTPN22 G788A polymorphism confers protection against SLE, RA, and UC, supporting evidence of association of the PTPN22 gene with a subgroup of autoimmune diseases.

Epidemiology of inflammatory bowel disease in racial and ethnic migrant groups

AIM

To summarise the current literature and define patterns of disease in migrant and racial groups.

METHODS

A structured key word search in Ovid Medline and EMBASE was undertaken in accordance with PRISMA guidelines. Studies on incidence, prevalence and disease phenotype of migrants and races compared with indigenous groups were eligible for inclusion.

RESULTS

Thirty-three studies met the inclusion criteria. Individual studies showed significant differences in incidence, prevalence and disease phenotype between migrants or race and indigenous groups. Pooled analysis could only be undertaken for incidence studies on South Asians where there was significant heterogeneity between the studies [95% for ulcerative colitis (UC), 83% for Crohn’s disease (CD)]. The difference between incidence rates was not significant with a rate ratio South Asian: Caucasian of 0.78 (95%CI: 0.22-2.78) for CD and 1.39 (95%CI: 0.84-2.32) for UC. South Asians showed consistently higher incidence and more extensive UC than the indigenous population in five countries. A similar pattern was observed for Hispanics in the United States. Bangladeshis and African Americans showed an increased risk of CD with perianal disease.

CONCLUSION

This review suggests that migration and race influence the risk of developing inflammatory bowel disease. This may be due to different inherent responses upon exposure to an environmental trigger in the adopted country. Further prospective studies on homogenous migrant populations are needed to validate these observations, with a parallel arm for in-depth investigation of putative drivers.

African Americans and Short-Term Outcomes after Surgery for Crohn's Disease: An ACS-NSQIP Analysis

BACKGROUND

Previous reports on racial disparities in the treatment of Crohn's disease [CD] in African American [AA] patients have shown differences in both medical and surgical treatments in this population. No study thus far has examined the effect of AA race on outcomes after surgery for CD.

METHODS

Utilizing the National Surgical Quality Improvement Program [NSQIP] Participant User File [PUF] for the years 2005-2013, we examined the effect of AA race on postoperative complications in patients with CD undergoing intestinal surgery.

RESULTS

AA patients had a significantly higher rate of complications overall compared to non-AA patients [23.5% vs 18.9%, p = 0.002]. Postoperative sepsis [10.9% vs 6.6%, p < 0.001] and surgical site infection [17.6% vs 14.8%, p = 0.037] were most significant. After adjustment for age, sex, preoperative disease severity and lifestyle factors [smoking], race remained a statistically significant factor in postoperative complication rate. Only after additional adjustment was made for comorbidities and American Society of Anesthesiologists class did race lose significance within our model.

CONCLUSION

African Americans experience a greater amount of postoperative complications following surgery for Crohn's disease. Preoperative disease management, addressing smoking status and control of comorbid disease are important factors in addressing the racial disparities in the surgical treatment of Crohn's disease.

Efficacy and Safety of Infliximab Therapy and Predictors of Response in Korean Patients with Crohn's Disease: A Nationwide, Multicenter Study

PURPOSE

Infliximab is currently used for the treatment of active Crohn's disease (CD). We aimed to assess the efficacy and safety of infliximab therapy and to determine the predictors of response in Korean patients with CD.

MATERIALS AND METHODS

A total of 317 patients who received at least one infliximab infusion for active luminal CD (n=198) and fistulizing CD (n=86) or both (n=33) were reviewed retrospectively in 29 Korean referral centers. Clinical outcomes of induction and maintenance therapy with infliximab, predictors of response, and adverse events were evaluated.

RESULTS

In patients with luminal CD, the rates of clinical response and remission at week 14 were 89.2% and 60.0%, respectively. Male gender and isolated colonic disease were associated with higher remission rates at week 14. In week-14 responders, the probabilities of sustained response and remission were 96.2% and 93.3% at week 30 and 88.0% and 77.0% at week 54, respectively. In patients with fistulizing CD, clinical response and remission were observed in 85.0% and 56.2% of patients, respectively, at week 14. In week-14 responders, the probabilities of sustained response and remission were 94.0% and 97.1%, respectively, at both week 30 and week 54. Thirty-nine patients (12.3%) experienced adverse events related to infliximab. Serious adverse events developed in 19 (6.0%) patients including seven cases of active pulmonary tuberculosis.

CONCLUSION

Infliximab induction and maintenance therapy are effective and well tolerable in Korean patients with luminal and fistulizing CD. However, clinicians must be aware of the risk of rare yet critical adverse events.

Fecal calprotectin correlated with endoscopic remission for Asian inflammatory bowel disease patients

AIM: To evaluate the correlation between fecal calprotectin (fC), C-reactive protein (CRP), and endoscopic disease score in Asian inflammatory bowel disease (IBD) patients.

METHODS: Stool samples were collected and assessed for calprotectin levels by Quantum Blue Calprotectin High Range Rapid test. Crohn’s disease endoscopic index of severity (CDEIS) and ulcerative colitis endoscopic index of severity (UCEIS) were used for endoscopic lesion scoring.

RESULTS: A total of 88 IBD patients [36 patients with Crohn’s disease (CD) and 52 with ulcerative colitis (UC)] were enrolled. For CD patients, fC correlated with CDEIS (r = 0.465, P = 0.005) and CRP (r = 0.528, P = 0.001). fC levels in UC patients correlated with UCEIS (r = 0.696, P < 0.0001) and CRP (r = 0.529, P = 0.0005). Calprotectin could predict endoscopic remission (CDEIS < 6) with 50% sensitivity and 100% specificity (AUC: 0.74) in CD patients when using 918 μg/g as the cut-off. When using 191 μg/g as the cut-off in UC patients, calprotectin could be used for predicting endoscopic remission (UCEIS < 3) with 88% sensitivity and 75% specificity (AUC: 0.87).

CONCLUSION: fC correlated with both CDEIS and UCEIS. fC could be used as a predictor of endoscopic remission for Asian IBD patients.

Association between a Functional HLA-G 14-bp Insertion/deletion Polymorphism and Susceptibility to Autoimmune Diseases: A Meta-analysis

The aim of this study was to determine whether a functional human leukocyte antigen-G (HLA-G) 14-bp insertion (I)/deletion (D) polymorphism is associated with susceptibility to autoimmune diseases. A meta-analysis was conducted to assess the association between an HLA-G 14-bp I/D polymorphism and autoimmune diseases using 1) allele contrast, as well as 2) recessive, 3) dominant, and 4) codominant models. Sixteen articles that included 20 comparative studies with 3,555 patients and 5,225 controls were included in the meta-analysis. These studies were performed on nine Caucasian, six South American, three Asian, one Arab, and one African population samples. Our meta-analysis revealed no association between autoimmune diseases and the HLA-G 14-bp I/D polymorphism [odds ratio (OR) for allele I = 1.055; 95% confidence interval (CI) = 0.963-1.156; p = 0.251)]. However, meta-analysis according to autoimmune disease type revealed an association between systemic lupus erythematosus (SLE) and the II+ID genotype of the HLA-G 14-bp I/D polymorphism (OR = 1.205; 95% CI = 1.036-1.403; p = 0.016). Furthermore, analysis using a codominant model revealed an association between this polymorphism and SLE (OR for ID vs. DD = 1.203; 95% CI = 1.024-1.413; p = 0.024). In contrast, our meta-analysis revealed no association between rheumatoid arthritis (RA), multiple sclerosis (MS), or Crohn's disease (CD) and the HLA-G 14-bp I/D polymorphism. This meta-analysis showed that the HLA-G 14-bp I/D polymorphism is associated with susceptibility to a subgroup of autoimmune diseases such as SLE, but not RA, MS, or CD. These results support the existence of an association between the HLA-G gene and a subgroup of autoimmune diseases.

Interleukin-18 genetic polymorphisms contribute differentially to the susceptibility to Crohn’s disease

AIM: To investigate the correlation between interleukin-18 (IL-18) gene polymorphisms and the risk of developing Crohn’s disease (CD).

METHODS: The PubMed, CISCOM, CINAHL, Web of Science, EBSCO, Cochrane Library, MEDLINE, EMBASE and CBM databases were searched without any language restrictions using combinations of keywords relating to CD and IL-18 for relevant articles published before November 1^st, 2013. Screening of the published studies retrieved from searches was based on our stringent inclusion and exclusion criteria and resulted in seven eligible studies for meta-analysis. A meta-analysis was conducted using a random-effects model with STATA 12.0 software. Crude odds ratios (ORs) with 95% confidence intervals (95%CI) were calculated.

RESULTS: Seven case-control studies, with a total of 1930 CD cases and 1930 healthy subjects, met our inclusion criteria. The results of our meta-analysis indicated that the IL-18 rs1946518 A>C and rs187238 G>C polymorphisms may correlate with an increased risk of CD under five genetic models (all P < 0.05). Furthermore, we observed positive associations between the IL-18 rs360718 A>C polymorphism and CD risk under three genetic models (C allele vs A allele: OR = 2.03, 95%CI: 1.20-3.43, P = 0.008; CC vs AA+AC: OR = 2.39, 95%CI: 1.2-4.43, P = 0.006; CC vs AC: OR = 2.31, 95%CI: 1.22-4.38, P = 0.010). However, such associations were not found for the IL-18 rs917997 C>T, codon 35 A>C and rs1946519 G>T polymorphisms (all P > 0.05). A subgroup analysis was conducted to investigate the effect of ethnicity on an individual’s susceptibility to CD. Our results revealed positive correlations between IL-18 genetic polymorphisms and an increased risk of CD among Asians and Africans (all P < 0.05), but not among Caucasians (all P > 0.05).

CONCLUSION: This meta-analysis indicated that the IL-18 rs1946518 A>C, rs187238 G>C and rs360718 A>C polymorphisms may contribute to susceptibility to CD, especially among Asians and Africans. These polymorphisms are known to reduce IL-18 mRNA and protein levels.

NOD2/CARD15 gene mutations in North Algerian patients with inflammatory bowel disease

AIM: To analyse allelic frequency of NOD2 gene variants and to assess their correlation with inflammatory bowel disease (IBD) in Algeria.

METHODS: We studied 132 unrelated patients diagnosed with IBD, 86 with Crohn’s disease (CD) and 46 with ulcerative colitis (UC). Data was prospectively collected between January 2011 and December 2013. The demographic and clinical characteristics were recorded for all the patients. A group of 114 healthy unrelated individuals were selected as controls. All groups studied originated from different regions of North Algeria and confirmed the Algerian origin of their parents and grandparents. Informed and written consent was obtained from each of the participants. All individuals were genotyped for the three CD-associated NOD2 variants (p.Arg⁷⁰²Trp, p.Gly908Arg and p.Leu¹⁰⁰⁷fsinsC mutations) using the polymerase chain reaction-restriction fragment length polymorphism method. Allele and genotype frequencies in patients and control subjects were compared by χ² test and Fisher’s exact test where appropriate. Odds ratios (OR) and 95% confidence intervals (95%CI) were also estimated. Association analyses were performed to study the influence of these variants on IBD and on clinical phenotypes.

RESULTS: The p.Arg⁷⁰²Trp mutation showed the highest frequency in CD patients (8%) compared to UC patients (2%) (P = 0.09, OR = 3.67, 95%CI: 0.48-4.87) and controls (5%) (P = 0.4, OR = 1.47, 95%CI: 0.65-3.31). In CD patients allelic frequencies of p.Gly908Arg and p.Leu¹⁰⁰⁷fsinsC variants compared to HC were 3% vs 2% (P = 0.5, OR = 1.67, 95%CI: 0.44-6.34); 2% vs 1% (P = 0.4 OR = 2.69 95%CI: 0.48-14.87 respectively). In UC patients, allelic frequencies of p.Gly908Arg and p.Leu¹⁰⁰⁷fsinsC variants compared to HC were 1% vs 2% (P = 1, OR = 1.62, 95%CI: 0.17-4.74) and 2% vs 1% (P = 0.32, OR = 0.39, 95%CI: 0.05-2.87). The total frequency of the mutated NOD2 chromosomes was higher in CD (13%), than in HC (8%) and UC (5%). In addition, NOD2 variants were linked to a particular clinical sub-phenotype in CD in this Algerian cohort. As expected, the three NOD2 variants showed a significant association with CD but did not reach statistical significance, despite the fact that the allele frequency of NOD2 variants was in the range found in most of the European populations. This might be due to the non-exposure of the NOD2 carriers to environmental factors, required for the expression of the disease.

CONCLUSION: Further analyses are necessary to study genetic and environmental factors in IBD in the Algerian population, using larger patient groups.

Ethnic variations in the provision of biologic therapy for Crohn's disease: a Freedom of Information study

In this study, we investigate whether the provision of biologic therapy for Crohn's disease is equitable across South Asian and English groups in NHS Trusts, which serve areas with significant ethnic variation. Data were requested from 10 NHS Trusts using a Freedom of Information (FOI) approach. Details of numbers of patients by ethnicity treated with infliximab or adalumimab for Crohn's disease between 2010 and 2012 were requested. Using population-based estimates of disease prevalence and Census data on population structure, observed and expected numbers who should have received treatment were calculated. In three Trusts, the number of South Asian patients who received such treatment was significantly less than British/White patients. These were: Pennine Acute Hospitals NHS Trust covering Oldham and North Manchester, Barking, Havering & Redbridge University Hospitals NHS Trust and University Hospitals of Leicester NHS Trust. The study is limited by several factors: 1. The only data available on prevalence in both English and South Asian communities comes from Leicester and was published in 1993. More recent data suggests that the prevalence of Crohn's disease now approaches 150/10(5) compared to the 76/10(5) for English patients which was recorded in Leicester. However, the two subsequent studies on prevalence which were published in 2000 from the North of England and 2010 from Scotland do not provide a breakdown by ethnicity. 2. The data were collected by administrative staff using a variety of approaches to their Trust's data bases and so the techniques used in each Trust are not comparable. In addition, studies from elsewhere suggest that the quality of FOI data is affected by the motivation of staff who collect the data. 3. With the exception of Leicester, there was no quality check on the accuracy of the data. In Leicester, 139 patients were on a register of biologic therapy and this compared with 343 patients reported by the FOI request. However, the proportions of patients by type of treatment and by ethnicity were comparable in the two data sets. This suggests that the data on ethnic differences reported by the FOI study reflects real differences. Clearly, there are South Asian communities where patients with Crohn's disease appear not to receive appropriate treatment in the form of biologics, and the reasons behind this need further consideration and investigation. We need to develop robust methods of monitoring the provision of biologic therapy across ethnic groups and communities. It is unacceptable for there to be a difference based on such grounds.

Assessment of disease specific knowledge and health-related quality of life among United States military veterans with inflammatory bowel disease

AIM: To evaluate the association between patient disease knowledge of inflammatory bowel disease (IBD) and health related quality of life (HRQoL) and identify patient and disease related predictors of patient knowledge of IBD.

METHODS: We performed a cross-sectional study of IBD patients with an established diagnosis of IBD longer than 3 mo prior to enrollment. The Crohn’s and colitis knowledge score (CCKNOW) and short inflammatory bowel disease questionnaire (SIBDQ) were self-administered to assess patient knowledge of IBD and HRQoL, respectively. Demographic and disease characteristics were abstracted from the electronic medical record. The correlation between CCKNOW and SIBDQ scores was assessed by a linear regression model. Associations of patient knowledge and the variables of interest were calculated using ANOVA.

RESULTS: A total of 101 patients were recruited. Caucasian race, younger age at diagnosis, and having a college or post-graduate degree were significantly associated with higher CCKNOW scores. Patients with CD had higher CCKNOW scores compared to patients with ulcerative colitis and inflammatory bowel disease type unclassified, P < 0.01. There was no significant correlation between overall CCKNOW and SIBDQ scores (r² = 0.34, P = 0.13). The knowledge sub-domain of diet in CCKNOW was negatively correlated with HRQoL (r² = 0.69, P < 0.01).

CONCLUSION: IBD diagnosis at a younger age in addition to Caucasian race and higher education were significantly associated with higher knowledge about IBD. However, patient knowledge of IBD was not correlated with HRQoL. Further studies are required to study the effect of patient knowledge of IBD on other clinical outcomes.

Racial disparities in readmission, complications, and procedures in children with Crohn's disease

BACKGROUND

Racial disparities in care and outcomes contribute to mortality and morbidity in children; however, the role in pediatric Crohn's disease is unclear. In this study, we compared cohorts of black and white children with Crohn's disease to determine the extent race is associated with differences in readmissions, complications, and procedures among hospitalizations in the United States.

METHODS

Data were extracted from the Pediatric Health Information System (January 1, 2004-June 30, 2012) for patients with 21 years or younger hospitalized with a diagnosis of Crohn's disease. White and black cohorts were randomly selected in a 2:1 ratio by hospital. The primary outcome was time from index hospital discharge to readmission. The most frequent complications and procedures were evaluated by race.

RESULTS

There were 4377 patients. Black children had a shorter time to first readmission and higher probability of readmission (P = 0.009) and a 16% increase in risk of readmission compared with white children (P = 0.01). Black children had longer length of stay and higher frequency of overall and late (30-d to 12-mo postdischarge) readmissions (P < 0.001). During index hospitalization, more black children had perianal disease and anemia (P < 0.001). During any hospitalization, black children had higher incidence of perianal disease, anemia, and vitamin D deficiency, and greater number of perianal procedures, endoscopies, and blood product transfusion (P < 0.001).

CONCLUSIONS

There are differences in hospital readmissions, complications, and procedures among hospitalized children related to race. It is unclear whether these differences are due to genetic differences, worse intrinsic disease, adherence, access to treatment, or treatment disparities.

Inflammatory bowel disease in an underdeveloped region of Northeastern Brazil

AIM: To evaluate the demographic characteristics and clinical phenotypes of inflammatory bowel disease (IBD) in a geographic area in Northeastern Brazil.

METHODS: This retrospective study was conducted at the Hospital of the Federal University of Piauí in Northeastern Brazil. Demographic characteristics and clinical phenotypes of IBD were analyzed in relation to the time of diagnostic confirmation, which was defined as the date of disease onset. Data were collected between January 2011 and December 2012 and included all census patients 18 years of age or older during that period for whom there was diagnostic confirmation of Crohn’s disease (CD), ulcerative colitis (UC), or unclassified colitis according to the Montreal criteria. We also analyzed the period of time between the onset of clinical manifestations and the diagnosis of IBD (delay in the diagnosis). Statistical analyses included means and standard deviations for numeric variables and the Pearson χ² adherence test for nominal variables. The annual index occurrence and overall prevalence of IBD at our institution were also calculated, with P values < 0.05 indicating statistical significance. This study was approved by the Institutional Ethics and Research Committee.

RESULTS: A total of 252 patients with IBD were included, including 152 (60.3%) UC patients and 100 (39.7%) CD patients. The clinical and demographic characteristics of all patients with IBD showed a female to male ratio of 1.3:1.0 and a mean age of 35.2 (SD = 14.5) years. In addition, the majority of patients were miscegenated (171, 67.9%), had received higher education (157, 62.4%), lived in urban areas (217, 86.1%), and were under the age of 40 years (97, 62.5%). For patients with CD, according to the Montreal classification, the predominant features present from the onset of disease were an age between 17 and 40 years (A2); colonic disease location (L2); and nonstricturing, nonfistulizing disease behavior (B1). However, approximately one-quarter of all CD patients demonstrated perineal involvement. We also observed considerable delay in the diagnosis of IBD throughout the entire study period (mean = 35.5 mo). In addition, the annual index occurrence rose from 0.08 to 1.53 cases/10⁵ inhabitants/year during the study period, and the prevalence rate was 12.8 cases/10⁵ inhabitants in 2012. Over the last two decades, there was a noted increase in the frequency of IBD in the study area.

CONCLUSION: In this study, there was a predominance of patients with UC, young people under 40 years of age, individuals with racial miscegenation, and low annual incomes.

Ethnic variations in five lower gastrointestinal diseases: Scottish health and ethnicity linkage study

OBJECTIVES

Our objective was to augment the limited evidence mainly from local, clinical studies of ethnic differences in gastrointestinal disorders. Our question was: are there ethnic variations in hospitalisation/death for lower gastrointestinal disorders in Scotland?

SETTING

Scotland.

POPULATION

This retrospective-cohort linked 4.65 (of 4.9) million people in the 2001 census of Scotland (providing data on ethnicity, country of birth and indicators of socioeconomic deprivation) to 9 years of National Health Service hospitalisation and death records.

PRIMARY AND SECONDARY OUTCOME MEASURES AND ANALYSIS

For appendicitis, we studied all ages; for irritable bowel syndrome, ulcerative colitis, Crohn's disease and diverticular disease, we included those ≥20 years. Using Poisson regression (robust variance) we calculated, by ethnic group and sex, first-hospitalisation/death age-adjusted rates per 100,000 person-years, and relative risks (RRs) with 95% CIs multiplied by 100, so the White Scottish reference population had an RR=100.

RESULTS

There were ethnic variations; for example, for irritable bowel syndrome, RRs (95% CIs) were comparatively high in Other White British women (128.4 (111.0 to 148.6)), and low in Pakistani women (75.1 (60.6 to 93.1)). For appendicitis, RRs were high in men in Other White British (145.2 (127.8 to 164.9)), and low in most non-White groups, for example, Pakistanis (73.8 (56.9 to 95.6)). For ulcerative colitis, RRs were high in Indian (169.8 (109.7 to 262.7)) and Pakistani (160.8 (104.2 to 248.2)) men. For Crohn's disease, the RR was high in Pakistani men (209.2 (149.6 to 292.6)). For diverticular disease, RRs were high in Irish men (176.0 (156.9 to 197.5)), and any Mixed background women (144.6 (107.4 to 194.8)), and low in most non-White groups, for example, Chinese men (47.1 (31.0 to 71.6) and women (46.0 (30.4 to 69.8)).

CONCLUSIONS

Appendicitis and diverticular disease were comparatively low in most non-White groups, while ulcerative colitis and Crohn's disease were mostly higher in South Asians. Describing and understanding such patterns may help clinical practice and research internationally.

Clinical characteristics and treatment of inflammatory bowel disease: A comparison of Eastern and Western perspectives

Inflammatory bowel disease (IBD) is a chronic, relapsing intestinal inflammatory disorder with unidentified causes. Both environmental factors and genetic aspects are believed to be crucial to the pathogenesis of IBD. The incidence and prevalence of IBD have recently been increasing throughout Asia, presumably secondary to environmental changes. This increasing trend in IBD epidemiology necessitates specific health care planning and education in Asia. To this end, we must gain a precise understanding of the distinctive clinical and therapeutic characteristics of Asian patients with IBD. The phenotypes of IBD reportedly differ considerably between Asians and Caucasians. Thus, use of the same management strategies for these different populations may not be appropriate. Moreover, investigation of the Asian-specific clinical aspects of IBD offers the possibility of identifying causative factors in the pathogenesis of IBD in this geographical area. Accordingly, this review summarizes current knowledge of the phenotypic manifestations and management practices of patients with IBD, with a special focus on a comparison of Eastern and Western perspectives.

Association of MYO9B gene polymorphisms with inflammatory bowel disease in Chinese Han population

AIM: To explore the association of MYO9B gene polymorphisms with clinical phenotypes and intestinal permeability of individuals with inflammatory bowel disease (IBD) in China.

METHODS: A total of 442 IBD patients and 402 healthy volunteers were genotyped for two single nucleotides (rs962917 and rs1545620) using the ligase detection reaction and polymerase chain reaction. Allelic and genotype frequency analyses were performed for the two groups. Intestinal permeability was evaluated using lactulose (L) and mannitol (M) excretion. The association of MYO9B gene polymorphisms with intestinal permeability between the normal and high intestinal permeability groups was analyzed.

RESULTS: Overall, there was no significant difference in the genotypic and allelic frequencies of MYO9B between IBD patients and controls. Although no association was found with ulcerative colitis in the comparison between the subgroups, the frequencies of rs962917 and rs1545620 were different in the Crohn’s disease (CD) subgroup with ileocolitis (CC vs CT and TT, P = 0.014; and AA vs AC and CC, P = 0.022, respectively). rs1545620 variants appear to be the genetic susceptibility factor for perianal disease in CD patients (AA vs AC CC, P = 0.029). In addition, the L/M ratio was significantly higher in IBD patients than in controls (0.065 ± 0.013 vs 0.020 ± 0.002, P = 0.02), but no association was found between the MYO9B gene and the L/M ratio in IBD patients.

CONCLUSION: MYO9B gene polymorphisms may influence the sub-phenotypic expression of CD in China. No association between these MYO9B polymorphisms and intestinal permeability in IBD patients was found.

Association between NOD2/CARD15 gene polymorphisms and Crohn's disease in Chinese Zhuang patients

AIM: To assess the relationship between the P268S, JW1 and N852S polymorphisms and Crohn’s disease (CD) susceptibility in Zhuang patients in Guangxi, China.

METHODS: Intestinal tissues from 102 Zhuang [48 CD and 54 ulcerative colitis (UC)] and 100 Han (50 CD and 50 UC) unrelated patients with inflammatory bowel disease and 72 Zhuang and 78 Han unrelated healthy individuals were collected in the Guangxi Zhuang Autonomous Region from January 2009 to March 2013. Genomic DNA was extracted using the phenol chloroform method. The P268S, JW1 and N852S polymorphisms were amplified using polymerase chain reaction (PCR), detected by restriction fragment length polymorphism (RFLP), and verified by gene sequencing.

RESULTS: Heterozygous mutation of P268S in the NOD2/CARD15 gene was detected in 10 CD cases (six Zhuang and four Han), two Han UC cases, and one Zhuang healthy control, and P268S was strongly associated with the Chinese Zhuang and Han CD populations (P = 0.016 and 0.022, respectively). No homozygous mutant P268S was detected in any of the groups. No significant difference was found in P268S genotype and allele frequencies between UC and control groups (P > 0.05). Patients with CD who carried P268S were likely to be ≤ 40 years of age (P = 0.040), but were not significantly different with regard to race, lesion site, complications, and other clinical features (P > 0.05). Neither JW1 nor N852S polymorphisms of the NOD2/CARD15 gene were found in any of the subjects (P > 0.05).

CONCLUSION: P268S polymorphism may be associated with CD susceptibility in the Zhuang population in the Guangxi Zhuang Autonomous Region, China. In contrast, JW1 and N852S polymorphisms may not be related to CD susceptibility in these patients.

RAGE gene three polymorphisms with Crohn's disease susceptibility in Chinese Han population

AIM: To investigate the association of three polymorphisms in the receptor for advanced glycation end product (RAGE) gene with Crohn’s disease (CD) risk in a Chinese population.

METHODS: A hospital-based case-control association study involving 312 CD patients and 479 healthy controls was conducted. Peripheral blood samples were collected from 791 study subjects, and genomic DNA was extracted. Genotyping was performed using polymerase chain reaction-ligase detection reaction method. The association between polymorphic genotype and CD predisposition was determined using odds ratio and 95% confidence interval (CI). Data were analyzed using Haplo.stats program.

RESULTS: Significant differences were observed between patients and controls in allele/genotype distributions of rs1800624 (P_allele=0.012; P_genotype=0.005) and in allele distributions of rs2070600 (P=0.02). The risk for CD associated with the rs1800624-A mutant allele decreased by 36% (95%CI: 0.47-0.88, P = 0.005) under the additive model and by 35% (95%CI: 0.46-0.91, P=0.013) under the dominant model. Carriers of rs2070600-A mutant allele showed a 37% (95%CI: 1.02-1.83, P=0.036) increased risk of developing CD relative to the GG genotype carriers. In haplotype analysis, haplotype T-A-G (in the order rs1800625, rs1800624, and rs2070600) decreased the odds of CD by 33% (95%CI: 0.49-0.94, P=0.018).

CONCLUSION: CD is an immune-related disease with genetic predisposition. Genetic defects in the RAGE gene are strongly associated with CD in Chinese population.

Macrophage migration inhibitory factor gene polymorphisms in inflammatory bowel disease: An association study in New Zealand Caucasians and meta-analysis

AIM: To investigate the association of macrophage migration inhibitory factor (MIF) promoter polymorphisms with inflammatory bowel disease (IBD) risk.

METHODS: One thousand and six New Zealand Caucasian cases and 540 Caucasian controls were genotyped for the MIF SNP -173G > C (rs755622) and the repeat polymorphism CATT_5-8 (rs5844572) using a pre-designed TaqMan SNP assay and capillary electrophoresis, respectively. Data were analysed for single site and haplotype association with IBD risk and phenotype. Meta-analysis was employed, to assess cumulative evidence of association of MIF -173G > C with IBD. All published genotype data for MIF -173G > C in IBD were identified using PubMed and subsequently searching the references of all PubMed-identified studies. Imputed genotypes for MIF -173G > C were generated from the Wellcome Trust Case Control Consortium (and National Institute of Diabetes and Digestive and Kidney Diseases). Separate meta-analyses were performed on Caucasian Crohn’s disease (CD) (3863 patients, 6031 controls), Caucasian ulcerative colitis (UC) (1260 patients, 1987 controls), and East Asian UC (416 patients and 789 controls) datasets using the Mantel-Haenszel method. The New Zealand dataset had 93% power, and the meta-analyses had 100% power to detect an effect size of OR = 1.40 at α = 0.05, respectively.

RESULTS: In our New Zealand dataset, single-site analysis found no evidence of association of MIF polymorphisms with overall risk of CD, UC, and IBD or disease phenotype (all P values > 0.05). Haplotype analysis found the CATT₅/-173C haplotype occurred at a higher frequency in New Zealand controls compared to IBD patients (0.6 vs 0.01; P = 0.03, OR = 0.22; 95%CI: 0.05-0.99), but this association did not survive bonferroni correction. Meta-analysis of our New Zealand MIF -173G > C data with data from seven additional Caucasian datasets using a random effects model found no association of MIF polymorphisms with CD, UC, or overall IBD. Similarly, meta-analysis of all published MIF -173G > C data from East Asian datasets (416 UC patients, 789 controls) found no association of this promoter polymorphism with UC.

CONCLUSION: We found no evidence of association of MIF promoter polymorphisms with IBD.

Inflammatory bowel disease serology in Asia and the West

AIM: To study serological antibodies in Caucasians and Asians, in health and inflammatory bowel disease (IBD), in Australia and Hong Kong (HK).

METHODS: Anti-glycan antibodies [anti-chitobioside (ACCA), anti-laminaribioside (ALCA)], and anti-mannobioside (AMCA), anti-Saccharomyces cervisiae (gASCA); and atypical perinuclear anti-neutrophil cytoplasmic antibody (pANCA) were tested in IBD patients, their unaffected relatives, and healthy controls in Australia and HK (China). Antibody status (positive or negative) and titre was compared between subjects of different geography, ethnicity and disease state.

RESULTS: Ninety subjects were evaluated: 21 Crohn’s disease (CD), 32 ulcerative colitis (UC), 29 healthy controls, and 8 IBD patient relatives. Forty eight subjects were Australian (29 Caucasian and 19 ethnic Han Chinese) and 42 were from HK (all Han Chinese). Caucasian CD patients had a significantly higher antibody prevalence of gASCA (67% vs 3%, P < 0.001), ALCA (44% vs 6%, P = 0.005), and AMCA (67% vs 15%, P = 0.002), whereas HK CD patients had a higher prevalence of only AMCA (58% vs 25%, P = 0.035), when compared with UC and healthy subjects in both countries. Caucasian CD had significantly higher gASCA prevalence (67% vs 0%, P < 0.001) and titre (median 59 vs 9, P = 0.002) than HK CD patients. Prevalence and titres of ALCA, ACCA and AMCA did not differ between CD in the two countries. Presence of at least one antibody was higher in Caucasian than HK CD patients (100% vs 58%, P = 0.045). pANCA did not differ between countries or ethnicity.

CONCLUSION: Serologic CD responses differ between HK Asian and Australian Caucasian patients. Different genetic, environmental or disease pathogenic factors may account for these differences.

Clinical effects of adalimumab treatment with concomitant azathioprine in Japanese Crohn’s disease patients

AIM: To assess adalimumab’s efficacy with concomitant azathioprine (AZA) for induction and maintenance of clinical remission in Japanese Crohn’s disease (CD) patients.

METHODS: This retrospective, observational, single-center study enrolled 28 consecutive CD patients treated with adalimumab (ADA). Mean age and mean disease duration were 38.1 ± 11.8 years and 11.8 ± 10.1 years, respectively. The baseline mean Crohn’s disease activity index (CDAI) and C-reactive protein were 177.8 ± 82.0 and 0.70 ± 0.83 mg/dL, respectively. Twelve of these patients also received a concomitant stable dose of AZA. ADA was subcutaneously administered: 160 mg at week 0, 80 mg at week 2, followed by 40 mg every other week. Clinical response and remission rates were assessed via CDAI and C-reactive protein for 24 wk.

RESULTS: The mean CDAI at weeks 2, 4, 8, and 24 was 124.4, 120.2, 123.6, and 135.1, respectively. The CDAI was significantly decreased at weeks 2 and 4 with ADA and was significantly suppressed at 24 wk with ADA/AZA. Overall clinical remission rates at weeks 4 and 24 were 66.7% and 63.2%, respectively. Although no statistically significant difference in C-reactive protein was demonstrated, ADA with AZA resulted in a greater statistically significant improvement in CDAI at 24 wk, compared to ADA alone.

CONCLUSION: Scheduled ADA with concomitant AZA may be more effective for clinical remission achievement at 24 wk in Japanese Crohn’s disease patients.

Primary sclerosing cholangitis, Crohn's disease and HLA-B27 in black South African women

Crohn's disease is rare in South African black people and primary sclerosing cholangitis (PSC) is also rare in black patients with IBD, from South Africa. The presence of HLA-B27 is generally associated with seronegative spondylo-arthropathies and correlates with the occurrence of ankylosing spondylitis, recurrent mouth ulcers and uveitis, in patients with IBD. We describe two women with the combination of Crohn's disease, PSC and HLA-B27 from our cohort of the last 5 years of three black patients with Crohn's disease. Crohn's disease, PSC and HLA-B27 respectively, occur rarely in black South Africans and their concurrent presence in two black women suggests a pathogenetic link of HLA-B27 between Crohn's disease and PSC in this population. Female gender might be an additional determinant in this setting.

Inflammatory bowel disease characteristics in Hispanic children in Texas

BACKGROUND

Inflammatory bowel disease (IBD) has a wide spectrum and variability among different ethnic groups. We aimed to evaluate disease characteristics in the pediatric Hispanic population, which has not been well studied.

METHODS

We identified patients <18 years old seen at Texas Children's Hospital (TCH) and diagnosed with IBD between 2004 and 2009. We compared them with their White, African American, and "other" counterparts with regard to their demographics, disease characteristics, and initial therapy.

RESULTS

There were a total of 399 patients with IBD: 211 (52.9%) White, 67 (16.8%) African American, 53 (13.3%) Hispanic, and 68 (17%) "other." Crohn's disease (CD) was the most common IBD type among all groups; however, Hispanics had the highest proportion of patients with ulcerative colitis (UC) and IBD-unclassified (IBD-U). There was male predominance in all groups except African Americans. Hispanics had the highest percentage of Medicaid coverage (P < 0.01) and none of the Hispanics had a first-degree relative with IBD. They had a younger age at diagnosis but a similar duration of symptoms prior to diagnosis. Hispanics had less failure to thrive and a higher body mass index (BMI) Z-score. Hispanics with CD more often received systemic steroids while those with UC and IBD-U were more often treated with local steroids (P < 0.01), oral 5-aminosalicylate (P < 0.01), and less often received immunomodulators or biologics (P = 0.05).

CONCLUSIONS

We demonstrate differences in disease characteristics between Hispanics and other ethnicities with IBD. Further epidemiologic studies are needed, including longer-term follow-up, to better define the burden of illness in Hispanics.

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.

Interactions between gastric and enteric infections: clues to the pathogenesis of inflammatory bowel disease?

Whereas the worldwide incidence of Crohn's disease (CD) continues to rise, Maori and Pacific Islanders living in New Zealand remain largely unaffected. The reason for this is currently unknown but may be linked to emerging evidence suggesting a role for Campylobacter spp in the aetiology of CD. Rates of campylobacteriosis are notably lower among Maori and Pacific Islanders and while this may reflect poorer access to primary care and diagnostic services, resulting in lower rates of notified disease, we consider it may also reflect a level of protective immunity in Maori and Pacific Islanders as a result of chronic infection from an early age with the closely related gastric pathogen Helicobacter pylori. Understanding the interactions between these antigenically-related bacteria may provide us with clues that ultimately help unravel the complex aetiology of CD.

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.

[Comparison of clinical manifestation and severity between hospital-based American and Chinese patients with colorectal Crohn disease]

OBJECTIVE

To evaluate the differences in clinicopathological characteristics and severity between American and Chinese patients with colorectal Crohn disease(CD).

METHODS

Between March 1985 and September 2004, 68 patients with colorectal CD in Cleveland Clinic Florida (America) and 85 patients with colorectal CD in the 301 Hospital(China) were enrolled in the study. Data of two groups,including demographics, clinical characteristics, extraintestinal manifestations, presenting symptoms, location and pathological characteristics,were compared.

RESULTS

60.3% of American patients and 36.5% of Chinese patients were female(P=0.003). 11.8% of American patients and 1.2% of Chinese patients had a family history of CD(P=0.016). American patients had a significantly higher rate of extraintestinal disease (39.7% vs 20.0%), abscess(19.0% vs 0), and anorectal fistulas(51.5% vs 0). American patients had significantly more extensive disease than Chinese patients(pancolitis: 44.1% vs 4.7%, P<0.01). American patients had a significantly higher rate of disease involving the ascending colon, transverse colon, descending colon, sigmoid colon, anorectal area compared with Chinese patients(all P<0.05).

CONCLUSIONS

American patients with colorectal Crohn disease seem to have a female predominance, a higher rate of CD family history, to involve the distal intestinal tract more often, and have more severe clinical manifestation and pathological process, as compared with Chinese patients.

[Toll-like receptor gene polymorphisms and susceptibility to inflammatory bowel disease in Chinese Han and Caucasian populations]

OBJECTIVE

To explore the distribution of Toll-like receptors gene polymorphisms in inflammatory bowel disease (IBD) in Chinese Han patients and Caucasians.

METHODS

The toll-like receptor 2 (TLR2) genes Arg677Trp and Arg753Glu, TLR4 genes Asp299Gly and Thr399Ile, and TLR9 gene 1237T/C polymorphisms were genotypes in 113 patients with IBD and 120 age and gender-matched healthy controls by the analyses of polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). A meta-analysis was performed to test whether TLR4 Asp299Gly and Thr399Ile polymorphisms were associated with ulcerative colitis (UC) or Crohn's disease (CD) susceptibility and whether 299Gly carriage was associated with phenotypes of CD patients in the Caucasian population.

RESULTS

We found two carriers of TLR9 1237C in UC patients, one carrier in CD patients and one in healthy controls respectively (CD: P = 0.361; UC: P = 0.569). There was no statistically significant difference in both allelic and genotypic frequencies. The mutant genotypes of TLR2 gene Arg677Trp and Arg753Glu, TLR4 gene Asp299Gly and Thr399Ile were not found in either the IBD patients or the healthy controls. The TLR4 299G allele showed a significant association with CD and UC in Caucasian population (OR = 1.29, 95%CI: 1.08 - 1.54, P = 0.004 and OR = 1.28, 95%CI: 1.08 - 1.51, P = 0.004 respectively). Similar association was detected between T399I polymorphism and susceptibility to IBD (OR = 1.37, 95%CI: 1.12 - 1.68, P = 0.002 and OR = 1.46, 95%CI: 1.13 - 1.88, P = 0.003 respectively). However, no significant association was identified between CD phenotypes and 299Gly carriage.

CONCLUSION

TLR2 genes Arg677Trp and Arg753Glu, TLR4 genes Asp299Gly and Thr399Ile and TLR9 gene 1237T/C polymorphisms are not associated with IBD in Chinese Han patients. In Caucasians, both TLR4 299G and 399I confer a significant risk for developing CD and UC. The contribution of genetic determinants may differ significantly between ethnicities.

Dietary factors in chronic inflammation: food tolerances and intolerances of a New Zealand Caucasian Crohn's disease population

Diet is known to play a major role in the symptoms of the inflammatory bowel disease, Crohn's disease (CD). Although no single diet is appropriate to all individuals, most CD patients are aware of foods that provide adverse or beneficial effects. This study seeks to categorise foods in relation to their effects on symptoms of CD, in a New Zealand Caucasian population. Four hundred and forty-six subjects from two different centres in New Zealand were recruited into the study. An extensive dietary questionnaire (257 food items in 15 groups) recorded self-reported dietary tolerances and intolerances. Across each of the food groups, there were statistically significant differences among responses to foods. A two-dimensional graphical summary enabled stratification of foods according to the probability that they will be either beneficial or detrimental. A small number of foods are frequently considered to be beneficial, including white fish, salmon and tuna, gluten-free products, oatmeal, bananas, boiled potatoes, sweet potatoes (kumara), pumpkin, soya milk, goat's milk and yoghurt. Foods that are typically considered detrimental include grapefruit, chilli or chilli sauce, corn and corn products, peanuts, cream, salami, curried foods, cola drinks, high energy drinks, beer, and red wine. For a number of the food items, the same item that was beneficial for one group of subjects was detrimental to others; in particular soya milk, goat's milk, yoghurt, oatmeal, kiwifruit, prunes, apple, broccoli, cauliflower, linseed, pumpkin seed, sunflower seed, ginger and ginger products, beef, lamb, liver, and oily fish. It was not possible to identify a specific group of food items that should be avoided by all CD patients. The wide range of detrimental items suggests that dietary maintenance of remission is likely to be difficult, and to exclude a substantial number of foods. Personalised diets may be especially important to these individuals.

Autophagy 16-like 1 rs2241880 G allele is associated with Crohn's disease in German children

AIM

Genome-wide association studies have described an association of the ATG16L1 (autophagy 16-like 1) gene rs2241880 variant with Crohn's disease (CD). Therefore, we evaluated this polymorphism in early-onset CD in 152 children and 253 controls and for the first time determined ATG16L1 colonic expression in German CD children.

METHODS

Investigation of rs2241880 allele frequencies using a predesigned single nucleotide polymorphism genotyping assay. Analysis of digenic epistasis between rs2241880 and the three common nucleotide-binding oligomerization domain containing two (NOD2/CARD15) mutations. Determination of ATG16L1 gene expression in large-bowel biopsies of selected patients and controls using real-time polymerase chain reaction.

RESULTS

The rs2241880G risk allele frequency was higher in CD compared with controls (63.0% vs. 47.4%; p = 0.0002). No epistasis between NOD2/CARD15 mutations and rs2241880 was observed; however, carriers of both variants had significantly increased disease risk. Transcriptional analysis did not reveal over- or underexpression of ATG16L1 in CD patients compared with controls.

CONCLUSION

We confirmed the association of CD with ATG16L1 rs2241880 variant in early-onset CD. As no epistatic interaction with three common NOD2/CARD15 mutations was observed, the p.Thr300Ala substitution is an independent risk factor for paediatric CD and supports the role for autophagy in disease pathogenesis.

Clinical features of ulcerative colitis and Crohn's disease in Turkey

BACKGROUND AND AIMS

This study is aimed at determining the clinical and socio-demographic characteristics of Turkish patients with inflammatory bowel disease who have been treated in a tertiary referral center.

PATIENTS AND METHODS

The study was conducted between 1993 and 2007 at Ankara Yuksek Ihtisas Hospital, Inflammatory Bowel Disease Clinics. The clinical and epidemiologic data from this clinic were gathered and analysed.

RESULTS

During the study period, 702 patients were identified as having inflammatory bowel disease; among these, 507 with ulcerative colitis (72.2%) and 195 with Crohn's disease (27.8%). The mean age at diagnosis was 46.2 years in ulcerative colitis and 40 years in Crohn's disease (p < 0.001). The male to female ratio was 1.2 for ulcerative colitis and 1.6 for Crohn's disease (p = 0.12). Of the patients who were primarily diagnosed with ulcerative colitis 16.8% had their diagnoses changed to Crohn's disease after the follow-up period.

CONCLUSIONS

Peak age of onset for both Crohn's disease and ulcerative colitis were similar to other countries. A slight male predominance of Crohn's disease and ulcerative colitis were found for Turkish patients. Though it takes longer to diagnose, Crohn's disease may have a milder course in Turkish patients.

IBD-associated TL1A gene (TNFSF15) haplotypes determine increased expression of TL1A protein

Background

The recently identified member of the TNF superfamily TL1A (TNFSF15) increases IFN-γ production by T cells in peripheral and mucosal CCR9+ T cells. TL1A and its receptor DR3 are up-regulated during chronic intestinal inflammation in ulcerative colitis and Crohn's disease (CD). TL1A gene haplotypes increase CD susceptibility in Japanese, European, and US cohorts.

Methodology and Principal Findings

Here we report that the presence of TL1A gene haplotype B increases risk in Jewish CD patients with antibody titers for the E. coli outer membrane porin C (OmpC+) (Haplotype B frequency in Jewish CD patients: 24.9% for OmpC negative and 41.9% for OmpC positive patients, respectively, P≤0.001). CD14+ monocytes isolated from Jewish OmpC+ patients homozygous for TL1A gene haplotype B express higher levels of TL1A in response to FcγR stimulation, a known inducing pathway of TL1A, as measured by ELISA. Furthermore, the membrane expression of TL1A is increased on peripheral monocytes from Jewish but not non-Jewish CD patients with the risk haplotype.

Conclusions and Significance

These findings suggest that TL1A gene variation exacerbates induction of TL1A in response to FcγR stimulation in Jewish CD patients and this may lead to chronic intestinal inflammation via overwhelming T cell responses. Thus, TL1A may provide an important target for therapeutic intervention in this subgroup of IBD patients.

The effect of tacrolimus (FK-506) on Japanese patients with refractory Crohn's disease

BACKGROUND

Recent evidence indicates that intravenous or oral therapy with tacrolimus (FK-506) is effective in treating patients with Crohn's disease. We evaluated the usefulness of tacrolimus therapy for Japanese patients with refractory Crohn's disease.

METHODS

Fourteen adult Japanese patients with Crohn's disease that was refractory to conventional therapies, including prednisolone (n = 5), azathioprine (n = 6), and infliximab (n = 5), were enrolled. Treatment with tacrolimus was started orally or intravenously and aimed for serum trough levels of 10-15 ng/ml. After the patients achieved clinical improvement, tacrolimus maintenance therapy was administered to maintain the trough level at 5-10 ng/ml.

RESULTS

All patients achieved remission or significant improvement 40 days after starting tacrolimus treatment. By 120 days after the start of therapy, 9 (64%) patients achieved remission, 2 patients (14%) achieved significant improvement, and only 3 patients (21%) relapsed. The relapsed patients were treated with infliximab therapy and achieved remission. Steroids were discontinued by the 5 patients who had taken steroids before the study began. Adverse effects of tacrolimus included a temporary increase in serum creatinine concentration (n = 1, 7%), hyperkalemia (n = 1, 7%), and tremor (n = 1, 7%).

CONCLUSIONS

Tacrolimus therapy is effective and well tolerated in patients with Crohn's disease that is refractory to conventional therapies.

ATG16L1 and IL23 receptor (IL23R) genes are associated with disease susceptibility in Hungarian CD patients

BACKGROUND

North American and European genome-wide association scans have identified ATG16L1 and IL23R as novel inflammatory bowel disease (IBD) susceptibility genes and subsequent reports confirmed these findings in large independent populations. The aims of this study were to investigate the association and examine genotype-phenotype relationships in a Hungarian IBD cohort.

METHODS

415 unrelated IBD patients (CD: 266, age: 35.2+/-12.1 years, duration: 8.7+/-7.5 years and UC: 149, age: 44.4+/-15.4 years, duration: 10.7+/-8.9 years) and 149 healthy subjects were investigated. IL23R Arg381Gln (R381Q, rs11209026) and ATG16L1 Thr300Ala (T300A, rs2241880) polymorphisms were tested using LightCycler allele discrimination method. Detailed clinical phenotypes were determined by reviewing the medical charts.

RESULTS

The association between IL23R rs11209026, ATG16L1 rs2241880 and CD was confirmed (OR(IL23R381Q): 0.38, 95% CI: 0.16-0.87; OR(ATG16L1300AA): 1.86, 95% CI: 1.04-3.40). No difference was found between patients with UC and either controls or CD. In CD, IL23R 381Gln heterozygosity was associated with inflammatory disease (70% vs. 34%, p=0.037), while disease restricted to the colon was more prevalent in patients with the ATG16L1 300Ala/Ala homozygosity (33.3% vs. 21.1%, p=0.036). In addition, carriage of the variant alleles did not predict response to steroids, infliximab or need for surgery.

CONCLUSIONS

We confirmed that ATG16L1 and IL23R are susceptibility loci for CD in Hungarian CD patients. Further studies are needed to confirm the reported phenotype-genotype associations found in this study.

Evidence of allelic heterogeneity for associations between the NOD2/CARD15 gene and ulcerative colitis among North Indians

BACKGROUND

Three common disease susceptibility variants in the NOD2 gene are associated with inflammatory bowel disease in Caucasians, but not in Asians. Aim To screen for NOD2 variants and examine susceptibility for inflammatory bowel disease in North Indians.

METHODS

A case-control study was carried out in Punjab, India. Confirmed cases of ulcerative colitis and Crohn's disease and healthy controls matched for age (+/-10 years) and ethnicity were studied. Besides genotyping the three disease susceptibility variants (SNP8, SNP12 and SNP13), all 12 exons were resequenced to determine other potential single nucleotide polymorphisms.

RESULTS

Two hundred and ninety-eight ulcerative colitis, 25 Crohn's disease and 262 controls were investigated. Median age (range) at diagnosis was 39 (7-78) years for ulcerative colitis and 40 (32-58) years for Crohn's disease. All three disease susceptibility variants were either monomorphic or rare in the population. Sequencing (n = 30) revealed two single nucleotide polymorphisms: SNP5 (268 Pro/Ser) and rs2067085 (178 Ser/Ser). The frequency of SNP5 was higher among ulcerative colitis (17% vs. 12% in controls, P = 0.016) and Crohn's disease cases (20% vs. 12%, P = 0.28). SNP5 carriers had elevated risks for ulcerative colitis (OR = 1.72, 95% CI = 1.17-2.52, P = 0.005).

CONCLUSIONS

The absence of known inflammatory bowel disease susceptibility variants and potential associations between SNP5 and ulcerative colitis in North Indians suggests the presence of allelic heterogeneity for ulcerative colitis susceptibility.

Race and health insurance are predictors of hospitalized Crohn's disease patients undergoing bowel resection

BACKGROUND

Racial disparities in utilization of major surgical procedures have been well documented in the United States over the last decade. Crohn's disease (CD) is a chronically relapsing disorder that leads to significant morbidity and, in most cases, surgery. Our objective was to characterize health disparities in CD-related bowel resection among hospitalized CD patients.

METHODS

We analyzed discharge records from the Nationwide Inpatient Sample, the largest nationally representative database of acute-care hospitals throughout the United States. A total of 41,918 discharges with CD from 1998 to 2003 were included. Bowel resection and in-hospital mortality rates for non-Hispanic whites, African Americans, Hispanics, and non-Hispanic Asians were calculated.

RESULTS

After adjusting for age, sex, health insurance, comorbidity, median neighborhood income, and hospital characteristics, the relative rate ratio of undergoing bowel resection for African Americans, Hispanics, and Asians compared to whites was 0.68 (95% confidence interval [CI]: 0.61-0.76), 0.70 (95% CI: 0.60-0.83), and 0.31 (95% CI: 0.16-0.59), respectively. Compared to those with private insurance, the relative risk of surgery for those with Medicare, those with Medicaid, and those who were "self-pay" was 0.48 (95% CI: 0.44-0.54), 0.52 (95% CI: 0.46-0.59), and 0.67 (95% CI: 0.58-0.77), respectively. Women were less likely than men to undergo bowel resection (incidence rate ratio [IRR] = 0.80; 95% CI: 0.76-0.85). The in-hospital mortality of individuals who resided in neighborhoods whose median income was above the national median was lower (IRR = 0.71; 95% CI: 0.50-0.99).

CONCLUSIONS

Bowel resection among hospitalized CD patients varies by race, health insurance, and sex. Further mechanistic studies are needed to elucidate the social and biological underpinnings of these variations.

Crohn’s disease incidence evolution in North-western Greece is not associated with alteration of NOD2/CARD15 variants

AIM: To assess the trends in the incidence of inflammatory bowel disease (IBD) over 23 years in the same area and to identify genetic factors related to incidence evolution.

METHODS: Patients with IBD arising from North-western Greece were systematically recorded through the 1983-2005 period. Trends in disease incidence and genetic patterns related to CARD15 variants were documented and correlated.

RESULTS: A total of 447 patients with IBD were recorded (23.5% Crohn’s disease, 72.7% Ulcerative colitis and 3.8% indeterminate colitis). Mean annual incidence rates of CD and UC were 0.9/100 000 (95% CI 0.1-1.7) and 2.7/100 000 (95% CI 1.7-4.1) inhabitants, respectively. There was a statistically significant increase of CD incidence (P < 0.01) during the study period, in contrast to the UC incidence. There were no statistical differences in CARD15 variants over the study period.

CONCLUSION: The incidence of CD in North-western Greece has risen disproportionately to that of UC in the 21st century. This is not related to alterations of genetic background though.

Polymorphisms in NFKBIA and ICAM-1 genes in New Zealand Caucasian Crohn's disease patients

BACKGROUND AND AIM

Crohn's disease (CD) is a complex polygenetic inflammatory disease of the bowel. NFKBIA (IkappaBalpha) is a downstream regulator of NF-kappaB, which is an effector of the major Crohn's susceptibility gene CARD15/NOD2. ICAM-1 is an integrin ligand and vascular addressin, which contributes to the trafficking of pathogenic leukocytes into the inflamed bowel. Here we examined whether the NFKBIA 2758G/A and ICAM-1 K469E variants, recently shown to be CD susceptibility genes in Caucasian populations in Germany and the United Kingdom, are associated with CD in Caucasian patients in New Zealand.

METHODS

PCR-RFLP analysis was used to examine the frequency of gene polymorphisms in 182 CD patients and 188 ethnically matched controls.

RESULTS

There was no significant evidence of a difference in the allele frequency of either the 2758G/A polymorphism in NFKBIA (0.38 vs 0.35, P = 0.47) or the K469E polymorphism in ICAM-1 (0.43 vs 0.37, P = 0.10) between CD patients and controls. Nevertheless, the ICAM-1 469E allele significantly (P = 0.016, Pc = 0.047) influenced the age of diagnosis of CD. Meta-analysis with five other studies confirmed a lack of association of the K469E polymorphism with Crohn's disease (P = 0.33; OR = 0.93; 95% CI, 0.82-1.07).

CONCLUSION

The NFKBIA 2758G/A and ICAM-1 K469E polymorphisms are not significant risk factors for CD in New Zealand; however, there is evidence that the latter polymorphism influences the age of diagnosis.

Crohn’s disease in one mixed-race population in Brazil

AIM: To evaluate the classification and severity of Crohn's disease in different racial groups.

METHODS: Patients with Crohn’s disease from the outpatient clinic of the University Hospital Prof. Edgard Santos were enrolled in the study. This hospital is a reference centre for inflammatory bowel disease. Race was determined using self-identification. The Vienna's classification was applied for all subjects. The severity of Crohn's disease was determined according to the number of surgical procedures, hospital admissions in the last year and treatment with steroids and immunosuppressors. Statistical analysis was calculated using t test for means, χ² or F for proportions. A P value < 0.05 was considered to be significant.

RESULTS: Sixty-five patients were enrolled. Non-white patients were more frequently diagnosed with Crohn’s disease in the age less than 40 years than white patients. The behaviour of disease was similar in both groups with a high frequency of the penetrating form. There was a tendency for non-white patients to have a greater frequency of hospital admissions in the last year compared to white subjects. Non-whites also had a higher rate of colonic and upper gastrointestinal involvement, and were also more frequently on treatment with immunossupressors than white patients although this difference was not statistically significant.

CONCLUSION: Non-white patients with Crohn’s disease had an earlier diagnosis and appeared to have had a more severe disease presentation than white patients.

Lack of association of the 3'-UTR polymorphism in the NFKBIA gene with Crohn's disease in an Israeli cohort

BACKGROUND

Crohn's disease (CD) is a chronic inflammatory disease of the gastrointestinal tract associated with dysregulation of the immune response. It is caused by a combination of environmental and genetic factors. Patients with CD have a TH1-type inflammatory response characterized by nuclear factor kappa B (NFkappaB) activation. Mutations in the bacterial pattern recognition receptors NOD2/CARD15 and Toll-like receptor 4 (TLR4) genes, which lead to activation of NFkappaB under normal circumstances, have been associated with increased susceptibility for CD. NFkappaB plays a critical role in the immune response and is down-regulated by NFkappaB inhibitor alpha (NFKBIA). NFKBIA was found to be a susceptibility gene for German CD patients lacking NOD2/CARD15 mutations.

MATERIALS AND METHODS

A cohort of 231 Israeli CD patients previously genotyped for the single nucleotide polymorphisms (SNPs) in the CARD15, TLR4 susceptibility genes for CD, was analyzed for the 3'-untranslated region (UTR) SNP of the NFKBIA gene in comparison to 100 healthy ethnically matched controls. We evaluated the contribution of the 3'-UTR SNP in NFKBIA in patients with or without other SNPs in CARD15 to age of onset, disease location, and disease behavior (Vienna classification).

RESULTS

We did not identify a significant difference in allele and genotype frequencies between either groups or an effect on phenotype. No interactions were found between NFKBIA and any NOD2.

CONCLUSIONS

The contribution of population diversity to susceptibility genes for CD plays an important role in disease-associated variants and is important for better understanding of the pathologic mechanisms of the polymorphism.

Gender-stratified analysis of DLG5 R30Q in 4707 patients with Crohn disease and 4973 controls from 12 Caucasian cohorts

BACKGROUND

DLG5 p.R30Q has been reported to be associated with Crohn disease (CD), but this association has not been replicated in most studies. A recent analysis of gender-stratified data from two case-control studies and two population cohorts found an association of DLG5 30Q with increased risk of CD in men but not in women and found differences between 30Q population frequencies for males and females. Male-female differences in population allele frequencies and male-specific risk could explain the difficulty in replicating the association with CD.

METHODS

DLG5 R30Q genotype data were collected for patients with CD and controls from 11 studies that did not include gender-stratified allele counts in their published reports and tested for male-female frequency differences in controls and for case-control frequency differences in men and in women.

RESULTS

The data showed no male-female allele frequency differences in controls. An exact conditional test gave marginal evidence that 30Q is associated with decreased risk of CD in women (p = 0.049, OR = 0.87, 95% CI 0.77 to 1.00). There was also a trend towards reduced 30Q frequencies in male patients with CD compared with male controls, but this was not significant at the 0.05 level (p = 0.058, OR = 0.87, 95% CI 0.74 to 1.01). When data from this study were combined with previously published, gender-stratified data, the 30Q allele was found to be associated with decreased risk of CD in women (p = 0.010, OR = 0.86, 95% CI 0.76 to 0.97), but not in men.

CONCLUSION

DLG5 30Q is associated with a small reduction in risk of CD in women.