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- Andersen, Vibeke, et al.
(författare)
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Fibre intake and the development of inflammatory bowel disease : A European prospective multi-centre cohort study (EPIC-IBD)
- 2018
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Ingår i: Journal of Crohn's & Colitis. - : OXFORD UNIV PRESS. - 1873-9946 .- 1876-4479. ; 12:2, s. 129-136
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Tidskriftsartikel (refereegranskat)abstract
- Background and Aims: Population-based prospective cohort studies investigating fibre intake and development of inflammatory bowel disease are lacking. Our aim was to investigate the association between fibre intake and the development of Crohn's disease [CD] and ulcerative colitis [UC] in a large European population.Methods: In total, 401 326 participants, aged 20-80 years, were recruited in eight countries in Europe between 1991 and 1998. At baseline, fibre intake [total fibres, fibres from fruit, vegetables and cereals] was recorded using food frequency questionnaires. The cohort was monitored for the development of inflammatory bowel disease. Each case was matched with four controls and odds ratios [ORs] for the exposures were calculated using conditional logistic regression. Sensitivity analyses according to smoking status were computed.Results: In total, 104 and 221 participants developed incident CD and UC, respectively. For both CD and UC, there were no statistically significant associations with either quartiles, or trends across quartiles, for total fibre or any of the individual sources. The associations were not affected by adjusting for smoking and energy intake. Stratification according to smoking status showed null findings apart from an inverse association with cereal fibre and CD in non-smokers [Quartile 4 vs 1 OR = 0.12, 95% confidence interval = 0.02-0.75, p = 0.023, OR trend across quartiles = 0.50, 95% confidence interval = 0.29-0.86, p = 0.017].Conclusion: The results do not support the hypothesis that dietary fibre is involved in the aetiology of UC, although future work should investigate whether there may be a protective effect of specific types of fibre according to smoking status in CD.
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| 2. |
- Bonfiglio, F., et al.
(författare)
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Female-Specific Association Between Variants on Chromosome 9 and Self-Reported Diagnosis of Irritable Bowel Syndrome
- 2018
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Ingår i: Gastroenterology. - : Elsevier BV. - 0016-5085 .- 1528-0012. ; 155:1, s. 168-179
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND & AIMS: Genetic factors are believed to affect risk for irritable bowel syndrome (IBS), but there have been no sufficiently powered and adequately sized studies. To identify DNA variants associated with IBS risk, we performed a genome-wide association study (GWAS) of the large UK Biobank population-based cohort, which includes genotype and health data from 500,000 participants. METHODS: We studied 7,287,191 high-quality single nucleotide polymorphisms in individuals who self-reported a doctor's diagnosis of IBS (cases; n = 9576) compared to the remainder of the cohort (controls; n = 336,499) (mean age of study subjects, 40-69 years). Genome-wide significant findings were further investigated in 2045 patients with IBS from tertiary centers and 7955 population controls from Europe and the United States, and a small general population sample from Sweden (n = 249). Functional annotation of GWAS results was carried out by integrating data from multiple biorepositories to obtain biological insights from the observed associations. RESULTS: We identified a genome-wide significant association on chromosome 9q31.2 (single nucleotide polymorphism rs10512344; P = 3.57 x 10(-8)) in a region previously linked to age at menarche, and 13 additional loci of suggestive significance (P < 5.0 x 10(-6)). Sex-stratified analyses revealed that the variants at 9q31.2 affect risk of IBS in women only (P = 4.29 x 10(-10) in UK Biobank) and also associate with constipation-predominant IBS in women (P = .015 in the tertiary cohort) and harder stools in women (P = .0012 in the population-based sample). Functional annotation of the 9q31.2 locus identified 8 candidate genes, including the elongator complex protein 1 gene (ELP1 or IKB-KAP), which is mutated in patients with familial dysautonomia. CONCLUSIONS: In a sufficiently powered GWAS of IBS, we associated variants at the locus 9q31.2 with risk of IBS in women. This observation may provide additional rationale for investigating the role of sex hormones and autonomic dysfunction in IBS.
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| 5. |
- Henstrom, M., et al.
(författare)
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Functional variants in the sucrase-isomaltase gene associate with increased risk of irritable bowel syndrome
- 2018
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Ingår i: Gut. - : BMJ. - 0017-5749 .- 1468-3288. ; 67:2, s. 263-270
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Tidskriftsartikel (refereegranskat)abstract
- Objective IBS is a common gut disorder of uncertain pathogenesis. Among other factors, genetics and certain foods are proposed to contribute. Congenital sucraseisomaltase deficiency (CSID) is a rare genetic form of disaccharide malabsorption characterised by diarrhoea, abdominal pain and bloating, which are features common to IBS. We tested sucrase-isomaltase (SI) gene variants for their potential relevance in IBS. Design We sequenced SI exons in seven familial cases, and screened four CSID mutations (p.Val557Gly, p. Gly1073Asp, p.Arg1124Ter and p.Phe1745Cys) and a common SI coding polymorphism (p.Val15Phe) in a multicentre cohort of 1887 cases and controls. We studied the effect of the 15Val to 15Phe substitution on SI function in vitro. We analysed p.Val15Phe genotype in relation to IBS status, stool frequency and faecal microbiota composition in 250 individuals from the general population. Results CSID mutations were more common in patients than asymptomatic controls (p=0.074; OR=1.84) and Exome Aggregation Consortium reference sequenced individuals (p=0.020; OR=1.57). 15Phe was detected in 6/7 sequenced familial cases, and increased IBS risk in case-control and population-based cohorts, with best evidence for diarrhoea phenotypes (combined p=0.00012; OR=1.36). In the population-based sample, 15Phe allele dosage correlated with stool frequency (p=0.026) and Parabacteroides faecal microbiota abundance (p=0.0024). The SI protein with 15Phe exhibited 35% reduced enzymatic activity in vitro compared with 15Val (p<0.05). Conclusions SI gene variants coding for disaccharidases with defective or reduced enzymatic activity predispose to IBS. This may help the identification of individuals at risk, and contribute to personalising treatment options in a subset of patients.
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| 6. |
- Salih, Abdulkadir, et al.
(författare)
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Smoking is associated with risk for developing inflammatory bowel disease including late onset ulcerative colitis : a prospective study
- 2018
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Ingår i: Scandinavian Journal of Gastroenterology. - : Taylor & Francis. - 0036-5521 .- 1502-7708. ; 53:2, s. 173-178
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: Life style factors have been associated with inflammatory bowel disease (IBD) but there is a lack of data on the exposure of life styles factors before the onset of IBD. Our aim was to study the association between lifestyle factors and the development of IBD in a prospective setting.Materials and methods: We performed a case control study of 72 patients who later developed ulcerative colitis (UC), 26 patients who developed Crohn's disease (CD) and 427 healthy controls from the Vasterbotten intervention project matched for gender, age, year of health survey and area of residence. At recruitment, participants completed validated lifestyle questionnaires including data on alcohol intake. Information from this was used to assess the connection between lifestyle factors and later developing IBD.Results: For CD and UC, the median age at diagnosis was 53 and 52 years and median time of survey was 4 and 6 years before diagnosis, respectively. Multivariate odds ratio (OR) showed an association between never smoking and not developing IBD, including both UC and CD, OR (95% CI) 0.341 (0.136-0.853) and 0.473 (0.259-0.864), respectively. Marital status, educational level, alcohol consumption, reported physical activity and use of moist smokeless tobacco (snus) did not differ between patients and controls.Conclusions: Smoking proves to be a risk factor for both CD and UC in this prospective case-control study. No association was seen for snus users, implying a non-nicotine pathogenic mechanism from combusted tobacco.
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| 7. |
- Wixner, Jonas, et al.
(författare)
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Abnormal small bowel motility in patients with hereditary transthyretin amyloidosis
- 2018
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Ingår i: Neurogastroenterology and Motility. - : Wiley. - 1350-1925 .- 1365-2982. ; 30:9
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundGastrointestinal complications are common in hereditary transthyretin amyloid (ATTRm) amyloidosis. The underlying mechanisms have not been fully elucidated, and the patients' small bowel function remains largely unexplored. The aim of the present study was to compare the small bowel motility in ATTRm amyloidosis patients with that in non-amyloidosis patient controls. MethodsATTRm amyloidosis patients undergoing evaluation for liver transplantation were consecutively investigated with 24-hour duodenojejunal manometry (n=19). The somatostatin analogue octreotide was used to induce fasting motility. Patients with age at onset of 50years were defined as late-onset cases. For each patient, three age- and sex-matched patient controls (n=57) were selected from the total pool of investigated patients. Key ResultsManometry was judged as abnormal in 58% of the patients and in 26% of the patient controls (P=.01). Patients displayed significantly more daytime phase III migrating motor complexes than patient controls (median 4 vs 2, P<.01), and had a higher frequency of low-amplitude complexes (16% vs 4%; however, this difference did not reach statistical significance, P=.10). Furthermore, late-onset patients showed a delay in octreotide response (5.4 vs 3.8minutes, P<.01), but this was not observed for early-onset patients or within the control group. Conclusions and InferencesPatients with ATTRm amyloidosis displayed abnormalities in their small bowel motility more frequently than non-amyloidosis patient controls, and the manometric pattern was probably best consistent with a combined neuromyopathic disorder. The delayed octreotide response in late-onset patients warrants further investigation.
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