Methods: A database search was performed up to July 2019 inclusive for all studies that compared H. pylori infection in IBD patients vs. non-IBD controls. The relative risk (RR) was used to quantify the association between IBD and H. pylori, and the effects were combined across studies using a mixed-effects meta-regression model, which included IBD subtype and geographic region as categorical moderator variables.
Results: Our meta-regression model exhibited moderate heterogeneity (I2=48.74%). Pooled RR depended on both region (P=0.02) and subtype (P<0.001). Pooled RRs were <1 for all subtype and region combinations, indicative of a protective effect of H. pylori against IBD. The pooled RR was 28% (9%, 50%; P=0.001) greater for UC vs. CD and 43% (4%, 96%; P=0.02) greater for Mediterranean countries vs. East Asia. The pooled RR was 18% (-13%, 60%; P=0.48) greater for Europe vs. East Asia and 21% (-13%, 68%; P=0.42) greater for Mediterranean vs. Europe, though these differences were not statistically significant.
Conclusions: The protective effect of H. pylori on IBD varied by both subtype (more protection against CD vs. UC) and region (East Asia more protected than Mediterranean regions). Variation due to these effects could provide insight into IBD etiology.
METHODS: Retrospective analysis of ulcerative colitis (UC) and Crohn's disease (CD), diagnosed from January 1980 till June 2018 was conducted at our centre.
RESULTS: A total of 413 IBD patients (281 UC, 132 CD) were identified. Mean crude incidence of IBD has increased steadily over the first three decades: 0.36 (1980-1989), 0.48 (1990-1999) and 0.63 per 100,000 person-years (2000-2009). In the 2010 to 2018 period, the mean crude incidence has doubled to 1.46 per 100,000 person-years. There was a significant rise in the incidence of CD, as depicted by reducing UC:CD ratio: 5:1 (1980-1989), 5:1 (1990-1999), 1.9:1 (2000-2009) and 1.7:1 (2010-2018). The prevalence rate of IBD, UC and CD, respectively were 23.0, 15.67 and 7.36 per 100,000 persons. Of all IBD patients, 61.5% (n = 254) were males. When stratified according to ethnic group, the highest prevalence of IBD was among the Indians: 73.4 per 100,000 persons, followed by Malays: 24.8 per 100,000 persons and Chinese: 14.6 per 100,000 persons. The mean age of diagnosis was 41.2 years for UC and 27.4 years for CD. Majority were non-smokers (UC: 76.9%, CD: 70.5%). The diseases were classified as follows: UC; proctitis (9.2%), left-sided colitis (50.2%) and extensive colitis (40.6%), CD; isolated ileal (22.7%), colonic (28.8%), ileocolonic (47.7%) and upper gastrointestinal (0.8%). 12.9% of CD patients had concurrent perianal disease. Extra intestinal manifestations were observed more in CD (53.8%) as compared to UC (12%). Dysplasia and malignancy, on the other hand, occurred more in UC (4.3%, n = 12) than in CD (0.8%, n = 1). Over one quarter (27.3%) of CD patients and 3.6% of UC patients received biologic therapy.
CONCLUSION: The incidence of IBD is rising in Malaysia, especially in the last one decade. This might be associated with the urbanization and changing diets. Public and clinicians' awareness of this emerging disease in Malaysia is important for the timely detection and management.
DESIGN: Prospective cohort study.
SETTING: 21 low, middle, and high income countries across seven geographical regions (Europe and North America, South America, Africa, Middle East, south Asia, South East Asia, and China).
PARTICIPANTS: 116 087 adults aged 35-70 years with at least one cycle of follow-up and complete baseline food frequency questionnaire (FFQ) data (country specific validated FFQs were used to document baseline dietary intake). Participants were followed prospectively at least every three years.
MAIN OUTCOME MEASURES: The main outcome was development of IBD, including Crohn's disease or ulcerative colitis. Associations between ultra-processed food intake and risk of IBD were assessed using Cox proportional hazard multivariable models. Results are presented as hazard ratios with 95% confidence intervals.
RESULTS: Participants were enrolled in the study between 2003 and 2016. During the median follow-up of 9.7 years (interquartile range 8.9-11.2 years), 467 participants developed incident IBD (90 with Crohn's disease and 377 with ulcerative colitis). After adjustment for potential confounding factors, higher intake of ultra-processed food was associated with a higher risk of incident IBD (hazard ratio 1.82, 95% confidence interval 1.22 to 2.72 for ≥5 servings/day and 1.67, 1.18 to 2.37 for 1-4 servings/day compared with <1 serving/day, P=0.006 for trend). Different subgroups of ultra-processed food, including soft drinks, refined sweetened foods, salty snacks, and processed meat, each were associated with higher hazard ratios for IBD. Results were consistent for Crohn's disease and ulcerative colitis with low heterogeneity. Intakes of white meat, red meat, dairy, starch, and fruit, vegetables, and legumes were not associated with incident IBD.
CONCLUSIONS: Higher intake of ultra-processed food was positively associated with risk of IBD. Further studies are needed to identify the contributory factors within ultra-processed foods.
STUDY REGISTRATION: ClinicalTrials.gov NCT03225586.
AIM: We investigated the association between air pollution exposure and IBD.
METHODS: The European Prospective Investigation into Cancer and Nutrition cohort was used to identify cases with Crohn's disease (CD) (n = 38) and ulcerative colitis (UC) (n = 104) and controls (n = 568) from Denmark, France, the Netherlands, and the UK, matched for center, gender, age, and date of recruitment. Air pollution data were obtained from the European Study of Cohorts for Air Pollution Effects. Residential exposure was assessed with land-use regression models for particulate matter with diameters of <10 μm (PM10), <2.5 μm (PM2.5), and between 2.5 and 10 μm (PMcoarse), soot (PM2.5 absorbance), nitrogen oxides, and two traffic indicators. Conditional logistic regression analyses were performed to calculate odds ratios (ORs) with 95 % confidence intervals (CIs).
RESULTS: Although air pollution was not significantly associated with CD or UC separately, the associations were mostly similar. Individuals with IBD were less likely to have higher exposure levels of PM2.5 and PM10, with ORs of 0.24 (95 % CI 0.07-0.81) per 5 μg/m(3) and 0.25 (95 % CI 0.08-0.78) per 10 μg/m(3), respectively. There was an inverse but nonsignificant association for PMcoarse. A higher nearby traffic load was positively associated with IBD [OR 1.60 (95 % CI 1.04-2.46) per 4,000,000 motor vehicles × m per day]. Other air pollutants were positively but not significantly associated with IBD.
CONCLUSION: Exposure to air pollution was not found to be consistently associated with IBD.
SUBJECTS/METHODS: Nested within the European Prospective Investigation into Cancer and Nutrition (EPIC-IBD), incident UC and CD cases and matched controls where included. At recruitment, participants completed validated food frequency and lifestyle questionnaires. Alcohol consumption was classified as either: non-use, former, light (⩽0.5 and 1 drink per week), below the recommended limits (BRL) (⩽1 and 2 drinks per day), moderate (⩽2.5 and 5 drinks per day), or heavy use (>2.5 and >5 drinks per day) for women and men, respectively; and was expressed as consumption at enrolment and during lifetime. Conditional logistic regression was applied adjusting for smoking and education, taking light users as the reference.
RESULTS: Out of 262 451 participants in six countries, 198 UC incident cases/792 controls and 84 CD cases/336 controls were included. At enrolment, 8%/27%/32%/23%/11% UC cases and 7%/29%/40%/19%/5% CD cases were: non-users, light, BRL, moderate and heavy users, respectively. The corresponding figures for lifetime non-use, former, light, BRL, moderate and heavy use were: 3%/5%/23%/44%/19%/6% and 5%/2%/25%/44%/23%/1% for UC and CD cases, respectively. There were no associations between any categories of alcohol consumption and risk of UC or CD in the unadjusted and adjusted odds ratios.
CONCLUSION: There was no evidence of associations between alcohol use and the odds of developing either UC or CD.
DESIGN: Electronic databases were searched up to July 2015 for all case-control studies on H. pylori infection/EHS/Campylobacter spp and IBD. Pooled ORs (P-OR) and 95% CIs were obtained using the random effects model. Heterogeneity, sensitivity and stratified analyses were performed.
RESULTS: Analyses comprising patients with Crohn's disease (CD), UC and IBD unclassified (IBDU), showed a consistent negative association between gastric H. pylori infection and IBD (P-OR: 0.43, p value <1e-10). This association appears to be stronger in patients with CD (P-OR: 0.38, p value <1e-10) and IBDU (P-OR: 0.43, p value=0.008) than UC (P-OR: 0.53, p value <1e-10). Stratification by age, ethnicity and medications showed significant results. In contrast to gastric H. pylori, non H. pylori-EHS (P-OR: 2.62, p value=0.001) and Campylobacter spp, in particular C. concisus (P-OR: 3.76, p value=0.006) and C. showae (P-OR: 2.39, p value=0.027), increase IBD risk.
CONCLUSIONS: H. pylori infection is negatively associated with IBD regardless of ethnicity, age, H. pylori detection methods and previous use of aminosalicylates and corticosteroids. Antibiotics influenced the magnitude of this association. Closely related bacteria including EHS and Campylobacter spp increase the risk of IBD. These results infer that H. pylori might exert an immunomodulatory effect in IBD.
METHODS: Within the prospective EPIC (European Prospective Investigation into Cancer) study, we set up a nested matched case-control study among 366,351 participants with inflammatory bowel disease data, including 256 incident cases of UC and 117 of CD, and 4 matched controls per case. Dietary intake was recorded at baseline from validated food frequency questionnaires. Incidence rate ratios of developing UC and CD were calculated for quintiles of the Mediterranean diet score and a posteriori dietary patterns produced by factor analysis.
RESULTS: No dietary pattern was associated with either UC or CD risks. However, when excluding cases occurring within the first 2 years after dietary assessment, there was a positive association between a "high sugar and soft drinks" pattern and UC risk (incidence rate ratios for the fifth versus first quintile, 1.68 [1.00-2.82]; Ptrend = 0.02). When considering the foods most associated with the pattern, high consumers of sugar and soft drinks were at higher UC risk only if they had low vegetables intakes.
CONCLUSIONS: A diet imbalance with high consumption of sugar and soft drinks and low consumption of vegetables was associated with UC risk. Further studies are needed to investigate whether microbiota alterations or other mechanisms mediate this association.