Citations

AbstractBackgroundEarly life events have been found to be associated with irritable bowel syndrome (IBS) suggesting a role in development of functional disorders. The study aim was to identify potential perinatal risk factors for adult IBS.MethodsUtilizing a population‐based nested case–control design, cases who met modified Rome III criteria for IBS and age‐ and‐gender matched controls were identified using responses from prior mailed surveys to a random sample of Olmsted County residents. Medical records of eligible respondents were reviewed for perinatal events of interest. The association of early life events with subsequent case status was assessed using conditional logistic regression.Key ResultsOf 3 417 respondents, 513 were born in Olmsted County and 108 met criteria for IBS. Due to missing records, 89 pairs were included in the final analyses. Logistic regression revealed only birth weight as a predictor of IBS. Lower birth weight increased the odds for IBS (OR = 1.54 [95% CI = (1.12, 2.08), p = 0.008]). Median birth weight was 3.35 kg (range: 1.96–5.24) and 3.57 kg (range: 2.18–4.59) for cases and controls, respectively. Maternal age, delivery method, and antibiotic exposure were not associated with IBS status but this study was only powered to detect large odds ratios.Conclusions and InferencesLower birth weight was observed as a risk factor for IBS. It is not clear if in utero developmental delays directly lead to IBS or if low birth weight is a prospective marker for subsequent early life problems leading to IBS.

Abstract Background Gastrointestinal infections are risk factors for irritable bowel syndrome ( IBS ) and functional dyspepsia ( FD ). We investigated whether non‐enteric infections and antibiotic exposure are also associated with the development of functional gastrointestinal disorders ( FGID s). Methods In a nested case–control study, random samples of Olmsted County, MN , were mailed valid self‐report questionnaires from 1988 through 1994, and then follow‐up questionnaires from 1995 through 2003. Survey responders who did not report any FGID symptoms at baseline, but then reported such symptoms in at least one subsequent survey, were classified as new‐onset cases. Age‐matched controls were individuals who did not have symptoms at either the initial or subsequent surveys. Key Results The overall response rate was 78% to the initial survey and 52% to the follow‐up survey. Based on the responses, 316 participants had a new onset of an FGID (43 IBS constipation, 95 IBS diarrhea, 25 IBS mixed, and 153 other FGID s, including FD ) and 250 did not (controls). Around 76% (241/316) of cases reported a non‐enteric infection vs 66% (166/250) of the controls. The frequency of enteric infections was similar between the two groups. Of the new FGID cases, 83% had a non‐enteric infection that was treated with antibiotic. In a logistic regression model, treatment with antibiotics for a non‐gastrointestinal infection was associated with the development of an FGID (odds ratio = 1.90; 95% CI : 1.21–2.98; p = 0.005), after adjusting for age and sex. Conclusions & Inferences Based on a case–control study, treatment of a non‐gastrointestinal infection with antibiotics appears to be a risk factor for development of an FGID .

BackgroundChronic constipation (CC) is common in the community but surprisingly little is known about relevant gastro‐intestinal (GI) and non‐GI co‐morbidities.ObjectiveThe purpose of this study was to assess the epidemiology of CC and in particular provide new insights into the co‐morbidities linked to this condition.MethodsIn a prospective, population‐based nested case‐control study, a cohort of randomly selected community residents (n = 8006) were mailed a validated self‐report gastrointestinal symptom questionnaire. CC was defined according to Rome III criteria. Medical records of each case and control were abstracted to identify potential CC comorbidities.ResultsAltogether 3831 (48%) subjects returned questionnaires; 307 met criteria for CC. Age‐adjusted prevalence in females was 8.7 (95% confidence interval (CI) 7.1–10.3) and 5.1 (3.6–6.7) in males, per 100 persons. CC was not associated with most GI pathology, but the odds for constipation were increased in subjects with anal surgery relative to those without (odds ratio (OR) = 3.3, 95% CI 1.2–9.1). In those with constipation vs those without, neurological diseases including Parkinson’s disease (OR = 6.5, 95% CI 2.9–14.4) and multiple sclerosis (OR = 5.5, 95% CI 1.9–15.8) showed significantly increased odds for chronic constipation, adjusting for age and gender. In addition, modestly increased odds for chronic constipation in those with angina (OR = 1.4, 95% CI 1.1–1.9) and myocardial infarction (OR = 1.5, 95% CI 1.0–2.4) were observed.ConclusionsNeurological and cardiovascular diseases are linked to constipation but in the community constipation is unlikely to account for most lower GI pathology.

SummaryBackgroundEstimation of the prevalence of oesophageal narrowing and its clinical relevance in patients with oesophageal eosinophilia is probably underestimated by endoscopy.AimsTo determine the sensitivity and specificity of oesophagogastroduodenoscopy (EGD) for oesophageal narrowing when compared to a structured oesophagram.MethodsWe conducted a retrospective chart review at Mayo Clinic, Rochester of adult patients with eosinophilic oesophageal infiltration of >15 eosinophils/hpf with symptomatic dysphagia, who underwent a structured barium oesophagram. The sensitivity and specificity of EGD were evaluated against the gold standard of oesophagram. Demographic and multiple clinical factors were evaluated as potential predictors of oesophageal narrowing.ResultsOf the 58 patients identified, 34 (58.6%) had a narrowed oesophageal diameter (<21 mm). EGD had poor sensitivity (14.7%, 95% CI 5.0–31.1%) for detection of a narrowed oesophagus and only modest specificity (79.2%, 95% CI 57.8–92.9%). Even at a cut‐off diameter of EDmax ≤ 15 mm, EGD had a sensitivity of only 25.0% (95% CI 5.5–57.2%) for narrowed oesophagus. A history of >5 food impaction episodes, endoscopic rings, and female sex were the best predictors of oesophageal narrowing. 86% (6/7) patients with persistent dysphagia despite remission of histological eosinophilia responded to oesophageal dilation all of whom had radiological oesophageal narrowing and 71% of whom had no perceived oesophageal narrowing at EGD.ConclusionsSymptomatic oesophageal narrowing identified by barium oesophagography is common and under‐recognised at endoscopy in patients with oesophageal eosinophilia.

Objective IBS shows genetic predisposition, but adequately powered gene-hunting efforts have been scarce so far. We sought to identify true IBS genetic risk factors by means of genome-wide association (GWA) and independent replication studies. Design We conducted a GWA study (GWAS) of IBS in a general population sample of 11 326 Swedish twins. IBS cases (N=534) and asymptomatic controls (N=4932) were identified based on questionnaire data. Suggestive association signals were followed-up in 3511 individuals from six case-control cohorts. We sought genotype-gene expression correlations through single nucleotide polymorphism (SNP)-expression quantitative trait loci interactions testing, and performed in silico prediction of gene function. We compared candidate gene expression by real-time qPCR in rectal mucosal biopsies of patients with IBS and controls. Results One locus at 7p22.1, which includes the genes KDELR2 (KDEL endoplasmic reticulum protein retention receptor 2) and GRID2IP (glutamate receptor, ionotropic, delta 2 (Grid2) interacting protein), showed consistent IBS risk effects in the index GWAS and all replication cohorts and reached p=9.31×10 −6 in a meta-analysis of all datasets. Several SNPs in this region are associated with cis effects on KDELR2 expression, and a trend for increased mucosal KDLER2 mRNA expression was observed in IBS cases compared with controls. Conclusions Our results demonstrate that general population-based studies combined with analyses of patient cohorts provide good opportunities for gene discovery in IBS. The 7p22.1 and other risk signals detected in this study constitute a good starting platform for hypothesis testing in future functional investigations.

AbstractBackgroundThere is symptom overlap between gastro‐esophageal reflux disease (GERD) and functional dyspepsia (FD). We aimed to test the hypothesis that FD cases are now more likely mislabeled as GERD.MethodsIn subjects from Olmsted County, MN seen at Mayo Clinic: (i) Investigation of GERD and FD diagnosis rates between 1985 and 2009. (ii) Assessment of survey‐based upper gastrointestinal symptoms between 1988 and 2009. (iii) Analysis of patients reporting GERD and/or FD symptoms and subsequently receiving a consistent diagnosis of GERD and/or FD during a medical encounter. (iv) Assess the association between PPI use and GERD and/or FD symptoms and between actual diagnoses received.Key Results(i) Yearly GERD diagnosis rates rose between 1985 and 2009 (325–1866 per 100 000). FD diagnosis rates rose from 45 in 1985, to 964 in 1999 but decreased to 452 per 100 000 in 2009. (ii) Reported GERD symptoms did not significantly change between three survey waves in the years 1988–2009 (p = 0.052), whereas FD symptoms slightly increased (p = 0.01). (iii) 62.9% of subjects reporting GERD symptoms received a GERD diagnosis, however only 12.5% of subjects reporting FD symptoms received a FD diagnosis. (iv) PPI use was associated with documented GERD diagnosis (p < 0.001), however there was no significant association between GERD symptoms and PPI use (p = 0.078).Conclusions & InferencesWe have found evidence supporting a systematic bias away from diagnosing FD, favoring a GERD diagnosis.

AbstractBackgroundThe etiology of irritable bowel syndrome (IBS) is not been fully elucidated, but childhood trauma may disturb the brain–gut axis and therefore be important. Thus, we conducted a family based case–control study of IBS cases and their relatives with the aims to (i) determine the frequency of childhood trauma among IBS cases and controls as well as their relatives, and (ii) assess childhood trauma among IBS cases with affected relatives (familial IBS).MethodsOutpatients with IBS, matched controls, and their first‐degree relatives completed a self‐report version of Bremner' Early Trauma Inventory. Percent of cases and controls with a family history were compared and odds ratios were computed using chi‐squared test; recurrence risks to relatives were computed using logistic regression and generalized estimating equations.Key ResultsData were collected from 409 cases, 415 controls, 825 case relatives, and 921 control relatives. IBS cases had a median age of 50 and 83% were women. Of IBS cases, 74% had experienced any general trauma compared to 59% among controls, yielding an odds ratio of 1.56 (95% CI: 1.13–2.15, p < 0.008). There were no statistical differences between IBS relatives and control relatives with regards to lifetime trauma.Conclusions & InferencesIBS is associated with childhood trauma, and these traumas often occur prior to onset of IBS symptoms. This provides further insight into how traumatic childhood events are associated with development of adult IBS.