Phenome-wide Mendelian randomization analysis reveals multiple health comorbidities of coeliac disease.

BACKGROUND: Coeliac disease (CeD) has been associated with a broad range of diseases in observational data; however, whether these associations are causal remains undetermined. We conducted a phenome-wide Mendelian randomization analysis (MR-PheWAS) to investigate the comorbidities of CeD. METHODS: Single nucleotide polymorphisms (SNPs) associated with CeD at the genome-wide significance threshold and without linkage disequilibrium (R2 <0.001) were selected from a genome-wide association study including 12,041 CeD cases as the instrumental variables. We first constructed a polygenic risk score for CeD and estimated its associations with 1060 unique clinical outcomes in the UK Biobank study (N = 385,917). We then used two-sample MR analysis to replicate the identified associations using data from the FinnGen study (N = 377,277). We performed a secondary analysis using a genetic instrument without extended MHC gene SNPs. FINDINGS: Genetic liability to CeD was associated with 68 clinical outcomes in the UK Biobank, and 38 of the associations were replicated in the FinnGen study. Genetic liability to CeD was associated with a higher risk of several autoimmune diseases (type 1 diabetes and its complications, Graves' disease, Sjögren syndrome, chronic hepatitis, systemic and cutaneous lupus erythematosus, and sarcoidosis), non-Hodgkin's lymphoma, and osteoporosis and a lower risk of prostate diseases. The associations for type 1 diabetes and non-Hodgkin's lymphoma attenuated when excluding SNPs in the MHC region, indicating shared genetic aetiology. INTERPRETATION: This study uncovers multiple clinical outcomes associated with genetic liability to CeD, which suggests the necessity of comorbidity monitoring among this population. FUNDING: This project was funded by Karolinska Institutet and the Swedish Research Council.

Older age of celiac disease diagnosis and risk of autoimmune disease: A nationwide matched case-control study.

OBJECTIVES: Celiac disease (CeD) has been linked to an increased risk of other autoimmune diseases, yet the impact of delayed CeD diagnosis on risk of developing additional autoimmune diseases remains uncertain. We investigated this through a nationwide matched case-control study. METHODS: Using the ESPRESSO cohort with histophatology data from Sweden's 28 pathology departments, we assessed 46,575 biopsy-confirmed CeD cases from 1964 to 2017. We extracted 225,295 matched controls without histopathology information from the Swedish Total Population Register. Autoimmune disease was defined through diagnostic codes in the National Patient Register. Through conditional logistic regression we estimated odds ratio (OR) of autoimmune disease up until CeD diagnosis/matching date comparing CeD cases to controls across different age strata. RESULTS: A total of 3059 (6.6 %) CeD patients and 4076 (1.8 %) controls had earlier autoimmune disease. The overall OR for autoimmune disease in CeD was 3.50 (95%CI 3.32-3.70). The risk of autoimmune disease did not escalate with increasing age at CeD diagnosis. Compared with controls, the OR of autoimmune disease in CeD patients was 7.70 (95%CI 4.71-12.57) in those diagnosed with CeD in 0-4 years, 19.02 (95%CI 13.80-26.23) in 5-9 years, 6.18 (95%CI 5.14-7.44) in 10-14 years, 4.80 (95%CI 3.97-5.79) in 15-19 years, 4.24 (95%CI 3.55-5.07) in 20-29 years, 4.65 (95%CI 3.93-5.51) in 30-39 years, 3.67 (95%CI 3.30-4.09) in 40-59 years, and 1.67 (95%CI 1.50-1.85) in ≥60 years. CONCLUSIONS: This study revealed an increased risk of autoimmune disease among CeD patients compared with controls. However, older age at CeD diagnosis did not seem to escalate the risk of autoimmune diseases.

Clinical Data Do Not Reliably Predict Duodenal Histology at Follow-up in Celiac Disease: A 13 Center Correlative Study.

Validated nonbiopsy methods to assure duodenal mucosal healing in celiac disease are lacking, yet ongoing mucosal injury is associated with anemia, osteoporosis, and lymphoma. Most providers utilize clinical data as surrogates of mucosal status to avoid additional esophagogastroduodenoscopy. The reliability of such surrogates to predict mucosal recovery has been incompletely evaluated. The aim of this study was to rigorously assess patterns of histologic mucosal recovery at follow-up in celiac disease and to correlate findings with clinical data. Gastrointestinal pathologists from 13 centers evaluated initial and follow-up duodenal biopsies from 181 celiac disease patients. Marsh scores and intraepithelial lymphocytes (IELs)/100 enterocytes were assessed blindly. Histology at follow-up was correlated with symptoms, immunoglobulin A anti-tissue transglutaminase titers and gluten-free diet adherence. Fifty-six/181 (31%) patients had persistent villous blunting and 46/181 (25%) patients had just persistently elevated IELs at follow-up, with only 79/181 (44%) patients having complete histologic remission. IEL normalization (82/181; 45%) lagged villous recovery (125/181;69%). In a minority of patients, villous blunting was limited to proximal duodenal biopsies. No correlation was found between Marsh scores and symptoms, normalization of immunoglobulin A anti-tissue transglutaminase serology, or diet adherence. Children showed greater recovery of Marsh score ( P <0.001) and IELs ( P <0.01) than adults. Persistent mucosal injury is common in celiac disease, with discordant villous/IEL normalization. Pathologist awareness of expected findings in celiac disease follow-up biopsies, including their frequent lack of correlation with clinical data, is important for patient management, and has implications for eligibility criteria for therapeutics currently in development.

A Composite Morphometric Duodenal Biopsy Mucosal Scale for Celiac Disease Encompassing Both Morphology and Inflammation.

BACKGROUND & AIMS: Villus height to crypt depth ratio (Vh:Cd) and intraepithelial lymphocytes (IEL) are key measures of histology of the small intestine in celiac disease. Although the field of celiac disease has advanced, there remains no broadly accepted measure of mucosal injury. We assessed whether a composite Vh:Cd and IEL scale (VCIEL) can improve accuracy and statistical precision for assessing histology, compared with individual measures. METHODS: The formulation of the VCIEL composite histologic scale was based on combining the Vh:Cd and IEL measurements for individual patients with equal weighting, by converting each scale to a fraction of their standard deviation and summing the results. The VCIEL formula was applied to several clinical trials and the results for Vh:Cd and IEL were compared with those for VCIEL with regards to clinical significance (effect size) and statistical significance. RESULTS: For the ALV003-1021 trial, we observed an effect size and P value (analysis of covariance) of 1.37 and 0.038 for ΔVh:Cd, 1.17 and 0.005 for ΔIEL, and 1.86 and 0.004 for ΔVCIEL. For the similar gluten-challenge IMGX003-NCCIH-1721 trial, the corresponding results were 0.76 and 0.057 for ΔVh:Cd, 0.98 and 0.018 for ΔIEL, and 1.14 and 0.007 for ΔVCIEL. Similar improvements with the use of VCIEL over individual Vh:Cd and IEL measures were observed for other studies, including a nontherapeutic gluten challenge study. CONCLUSIONS: The composite VCIEL scale combining Vh:Cd and IEL values seems to improve accuracy and statistical precision compared with either component alone.

Persistent villous atrophy predicts development of complications and mortality in adult patients with coeliac disease: a multicentre longitudinal cohort study and development of a score to identify high-risk patients.

OBJECTIVE: Persistent villous atrophy (pVA) in coeliac disease (CD) despite a gluten-free diet (GFD) has unclear meaning. We aimed to (i) study the relationship between pVA and long-term outcomes and (ii) develop a score to identify patients at risk of pVA. DESIGN: This is a multicentre retrospective-prospective study consisting of a study cohort (cohort 1) and an external validation cohort (cohort 2) of patients with biopsy-proven CD diagnosed between 2000 and 2021. Cohort 1 was used to (i) compare long-term outcomes between patients with and without pVA (Marsh ≥3a) at follow-up biopsy and (ii) to develop a score to evaluate the risk of pVA, which was validated in cohort 2. RESULTS: Of 2211 patients, 694 (31%) underwent follow-up duodenal biopsy and were included in the study cohort (491F, 44±16 years). 157/694 (23%) had pVA. Risk of complications (HR 9.53, 95% CI 4.77 to 19.04, p<0.001) and mortality (HR 2.93, 95% CI 1.43 to 6.02, p<0.01) were increased in patients with pVA. A 5-point score was developed and externally validated (receiver operating characteristic area under the curve 0.78, 95% CI 0.68 to 0.89) to stratify patients by risk of pVA: low (0-1 points, 5% pVA), intermediate (2 points, 16% pVA) and high (3-5 points, 73% pVA). Predictors for pVA used in the score were age at diagnosis ≥45 years (OR 2.01, 95% CI 1.21 to 3.34, p<0.01), classical pattern of CD (OR 2.14, 95% CI 1.28 to 3.58, p<0.01), lack of clinical response to GFD (OR 2.40, 95% CI 1.43 to 4.01, p<0.001) and poor GFD adherence (OR 48.9, 95% CI 26.1 to 91.8, p<0.001). CONCLUSIONS: Risk of complications and mortality were increased in patients with pVA. We developed a score to identify patients at risk of pVA and in need of histological reassessment and closer follow-up.

Short and long-term follow-up and clinical outcomes in patients with celiac disease in a large private practice setting.

BACKGROUND: Celiac disease (CD) is caused by an immune response to gluten and treatment is adherence to a gluten-free diet. Guidelines from studies in large academic settings recommend registered dietitian (RD) referrals at time of diagnosis and periodic testing for micronutrient deficiencies. There is limited data to guide follow-up parameters in a large, community-based practice. The purpose of this study was to evaluate guideline adherence in this setting. METHODS: This retrospective study conducted in 2019 assessed CD care based on follow-up rates, micronutrient testing, symptoms, and serology results in cohorts with and without RD referrals. Patients in this study were followed at Rockford Gastroenterology Associates (RGA): a large, private GI practice. Patients were included if they had a diagnosis of CD from 1/2014 through 12/2018, based on positive serology and/or duodenal biopsy. Patient data was collected by chart review and analyzed through Microsoft Excel. Fisher's exact and Chi-square tests were used for the statistical analysis and were calculated through the Statistical Product and Service Solutions (SPSS) software. RESULTS: 320 patients were initially reviewed and a cohort of 126 patients met inclusion criteria. 69.8% had a RD referral. 65.9% had at least one lab test order for any of the 6 micronutrients. Of 63 patients tested for iron, 11 were iron deficient (8 with RD referral). Of 64 patients tested for vitamin D, 21 were deficient (17 with referral). 80.2% attended at least one follow-up appointment, but 34.9% had only one follow-up visit over a mean follow up duration of 5.82 months. 79 patients had follow-up data for symptoms or serology and were separated into 4 categories (with vs. without RD referral): (1) asymptomatic and negative serology (32% vs. 26%), (2) symptomatic and negative serology (28% vs. 16%), (3) asymptomatic and positive serology (27% vs. 32%), (4) symptomatic and positive serology (13% vs. 26%). Category 1 yielded a fisher exact test value of 2.62 (p = 0.466). CONCLUSIONS: RD referral, micronutrient testing, and close follow-up are important parameters that affect outcomes in patients with CD. Rates for dietitian referral, some micronutrient testing and follow-up visits were higher than 50%, though results from this study were not statistically significant. Further standardization of follow-up testing and monitoring for CD will help minimize discrepancies between community-based and large, academic GI practices.

Celiac Disease Presenting in a Community-Based Gastroenterology Practice: Obesity and Bone Disease Are Common.

BACKGROUND: The description of the clinical presentation of celiac disease (CeD) has usually come from studies at referral centers. Data about CeD presentation in the community are sparse. AIMS: We aim to describe the clinical presentation of patients with biopsy-proven CeD at a community-based adult gastroenterology practice and compare it to a referral center. METHODS: We performed a retrospective study of two cohorts of patients diagnosed with CeD between 2000-2007 (n = 117) and 2013-2016 (n = 91) in a community practice, and a third cohort (n = 188) diagnosed between 2000 and 2007 in a tertiary referral center. The clinical presentation, body mass index, tissue-transglutaminase levels, DEXA scan, vitamin D levels, and vaccine recommendations were assessed. RESULTS: Celiac disease presentation changed over time in the two community cohorts. Recently, fewer patients presented with diarrhea and anemia, but constipation and neurologic symptoms were more common. The most recent cohort had a higher proportion of patients who were overweight or obese than the first cohort. However, the body mass index in both community cohorts was higher than in the tertiary referral center. The frequency of osteopenia and osteoporosis was high in both community cohorts. The tertiary referral center patients were younger, presented with a higher proportion of diarrhea and a lower body mass index. CONCLUSIONS: The clinical presentation of CeD differs between the community setting and a tertiary referral center. Patients with CeD presenting to the community setting tended to be older, overweight, and to have a high proportion of mineral bone disease.

Anemia Etiology and the Response to a Gluten-Free Diet in Untreated Patients With Celiac Disease: A 2-Year Follow-Up.

INTRODUCTION: Anemia and micronutrient deficiencies are common in newly diagnosed patients with celiac disease (CeD). We aim to determine the prevalence and etiology of anemia in a cohort of patients with CeD in the United States and examine the effect of a gluten-free diet (GFD) on the laboratory parameters related to anemia in CeD. METHODS: We analyzed a prospectively collected cohort of adults with biopsy-proven CeD followed in a specialized CeD center between January 2000 and June 2016. We used the level of hemoglobin (Hb) and micronutrients suggested by the World Health Organization to establish the diagnosis of anemia or deficiencies. Demographic data and laboratory parameters related to anemia and micronutrients were recorded at the time of diagnosis and on a GFD. A celiac expert nutritionist or gastroenterologist evaluated all patients. RESULTS: In 572 patients with laboratory evaluation before starting a GFD, approximately 25% presented with anemia at the time of diagnosis of CeD. Iron deficiency was present in 50.8% of the cohort and in 78.8% of the patients with anemia. Within the anemic population, 84.4% of female patients as compared with 58.3% of male patients ( P = 0.02) showed iron deficiency. Folate deficiency (23.2%), vitamin B12 deficiency (11%), and anemia of chronic diseases (7.8%) were also part of both sexes' anemia etiology. Of the initially anemic patients, 81% and 89% normalized their Hb levels within 1 year and 2 years of beginning a GFD, respectively. All patients received appropriate supplementation when needed. DISCUSSION: Approximately 25% of individuals have anemia at CeD diagnosis. The anemia etiology included iron deficiency, vitamin deficiencies, and anemia of chronic diseases. Most of the patients will normalize their Hb levels and the anemia laboratory parameters 1 year after starting a strict GFD.

Nomenclature and diagnosis of seronegative coeliac disease and chronic non-coeliac enteropathies in adults: the Paris consensus.

OBJECTIVE: Differential diagnosis of villous atrophy (VA) without coeliac antibodies in adults includes seronegative coeliac disease (CD) and chronic enteropathies unrelated to gluten, ie. non-coeliac enteropathies (NCEs). There is currently no international consensus on the nomenclature and diagnostic criteria for these enteropathies. In this work, a Delphi process was conducted to address this diagnostic and clinical uncertainty. DESIGN: An international task force of 13 gastroenterologists from six countries was recruited at the 16th International Coeliac Disease Symposium, Paris, 2019. Between September 2019 and July 2021, a Delphi process was conducted through mail surveys to reach a consensus on which conditions to consider in the differential diagnosis of VA with negative coeliac serology and the clinical diagnostic approaches required for these conditions. A 70% agreement threshold was adopted. RESULTS: Chronic enteropathies characterised by VA and negative coeliac serology can be attributed to two main clinical scenarios: forms of CD presenting with negative serology, which also include seronegative CD and CD associated with IgA deficiency, and NCEs, with the latter recognising different underlying aetiologies. A consensus was reached on the diagnostic criteria for NCEs assisting clinicians in differentiating NCEs from seronegative CD. Although in adults seronegative CD is the most common aetiology in patients with VA and negative serology, discriminating between seronegative CD and NCEs is key to avoid unnecessary lifelong gluten-free diet, treat disease-specific morbidity and contrast poor long-term outcomes. CONCLUSION: This paper describes the Paris consensus on the definitions and diagnostic criteria for seronegative CD and chronic NCEs in adults.

The global burden of coeliac disease: opportunities and challenges.

Coeliac disease is a systemic disorder characterized by immune-mediated enteropathy, which is caused by gluten ingestion in genetically susceptible individuals. The clinical presentation of coeliac disease is highly variable and ranges from malabsorption through solely extra-intestinal manifestations to asymptomatic. As a result, the majority of patients with coeliac disease remain undiagnosed, misdiagnosed or experience a substantial delay in diagnosis. Coeliac disease is diagnosed by a combination of serological findings of disease-related antibodies and histological evidence of villous abnormalities in duodenal biopsy samples. However, variability in histological grading and in the diagnostic performance of some commercially available serological tests remains unacceptably high and confirmatory assays are not readily available in many parts of the world. Currently, the only effective treatment for coeliac disease is a lifelong, strict, gluten-free diet. However, many barriers impede patients' adherence to this diet, including lack of widespread availability, high cost, cross-contamination and its overall restrictive nature. Routine follow-up is necessary to ensure adherence to a gluten-free diet but considerable variation is evident in follow-up protocols and the optimal disease management strategy is not clear. However, these challenges in the diagnosis and management of coeliac disease suggest opportunities for future research.

Clinical classification and long-term outcomes of seronegative coeliac disease: a 20-year multicentre follow-up study.

BACKGROUND: Seronegative coeliac disease is poorly defined. AIMS: To study clinical phenotypes and long-term outcomes of seronegative coeliac disease in a multicentre cohort over 20 years. METHODS: Seronegative coeliac disease was diagnosed in HLA-DQ2/DQ8-positive patients with villous atrophy (VA), negative IgA endomysial (EmA), tissue transglutaminase (tTG) and deamidated-gliadin antibodies (DGP), clinical and histological response to a gluten-free diet (GFD), and no alternative causes for VA. In patients with IgA deficiency, coeliac disease was diagnosed through VA, positive IgG EmA/tTG/DGP and clinical/histological response to a GFD (coeliac disease+IgAd). Patients with seropositive coeliac disease served as controls. RESULTS: Of 227 patients previously diagnosed with seronegative coeliac disease, true seronegative coeliac disease was confirmed in 84, coeliac disease+IgAd in 48, and excluded in 55. Lack of follow-up duodenal biopsy precluded diagnosing seronegative coeliac disease in 40 patients. 2084 patients with seropositive coeliac disease served as controls. True seronegative coeliac disease had more severe symptoms at diagnosis and a higher risk of complications (HR 10.87, 95% CI 6.11-19.33, P < 0.001) and mortality (HR 2.18, 95% CI 1.12-4.26, P < 0.01) than seropositive coeliac disease. There were no differences between true seronegative coeliac disease and coeliac disease+IgAd. On multivariate analysis, age at diagnosis, lack of clinical response to a GFD, true seronegative coeliac disease, coeliac disease+IgAd, and classical presentation predicted complications. Age at diagnosis, complications and absence of clinical response to a GFD predicted mortality. CONCLUSIONS: Seronegative coeliac disease has a more aggressive disease phenotype than seropositive coeliac disease. These data argue against over-reliance on serology for the diagnosis of coeliac disease and support a strict clinical and histologic follow-up in seronegative coeliac disease.

Understanding celiac disease monitoring patterns and outcomes after diagnosis: A multinational, retrospective chart review study.

BACKGROUND: Long-term outcomes and monitoring patterns in real-world practice are largely unknown among patients with celiac disease. AIM: To understand patterns of follow-up and management of patients with celiac disease, and to characterize symptoms and villous atrophy after diagnosis. METHODS: A retrospective chart review study was performed using medical chart data of patients diagnosed with celiac disease. Three gastroenterology referral centers, with substantial expertise in celiac disease, participated in the United Kingdom, United States, and Norway. Demographic and clinical data were collected from medical charts. Descriptive analyses were conducted on patients with biopsy-confirmed celiac disease, diagnosed between 2008 and 2012, with at least one follow-up visit before December 31, 2017. Patient demographic and clinical characteristics, biopsy/serology tests and results, symptoms, and comorbidities were captured at diagnosis and for each clinic visit occurring within the study period (i.e., before the study end date of December 31, 2017). RESULTS: A total of 300 patients were included in this study [72% female; mean age at diagnosis: 38.9 years, standard deviation (SD) 17.2]. Patients were followed-up for a mean of 29.9 mo (SD 22.1) and there were, on average, three follow-up visits per patient during the study period. Over two-thirds (68.4%) of patients were recorded as having ongoing gastrointestinal symptoms and 11.0% had ongoing symptoms and enteropathy during follow-up. Approximately 80% of patients were referred to a dietician at least once during the follow-up period. Half (50.0%) of the patients underwent at least one follow-up duodenal biopsy and 36.6% had continued villous atrophy. Patterns of monitoring varied between sites. Biopsies were conducted more frequently in Norway and patients in the United States had a longer follow-up duration. CONCLUSION: This real-world study demonstrates variable follow-up of patients with celiac disease despite most patients continuing to have abnormal histology and symptoms after diagnosis.

What is the Optimal Method Assessing for Persistent Villous Atrophy in Adult Coeliac Disease?

BACKGROUND AND AIMS: Methods of assessing gluten-free diet (GFD) adherence in adults with coeliac disease (CD) include serological testing, dietitian evaluation, questionnaires and repeat duodenal biopsies. Persisting villous atrophy (VA) is associated with CD complications, however gastroscopy with biopsies is expensive and invasive. This study aimed to assess the abilities of a duodenal bulb (D1) biopsy and the Celiac Dietary Adherence Test (CDAT) to detect persisting VA in adults with CD. METHODS: A prospective observational study of adult CD patients referred for follow-up duodenal biopsies was performed. Quadrantic biopsies were taken from the second part of the duodenum (D2), in addition to a D1 biopsy. Patients underwent follow-up serological testing, and completed the CDAT and Biagi Score. These non-invasive adherence markers were compared against duodenal histology. RESULTS: 368 patients (mean age 51.0 years, 70.1% female) had D1 and D2 biopsies taken at follow-up gastroscopy. Compared to D2 biopsies alone, additional D1 biopsies increased detection of VA by 10.4% (p<0.0001). 201 patients (mean age 50.3 years, 67.7% female) completed adherence questionnaires and serology. When detecting VA, sensitivities and specificities of these markers were 39.7% and 94.2% for IgA- tTG, 38.1% and 96.4% for IgA-EMA, 55.6% and 52.2% for CDAT and 20.6% and 96.4% for the Biagi score. CONCLUSIONS: Bulbar biopsies increase detection of persisting VA by 10.4%. Serology, CDAT and Biagi performed poorly when predicting VA. The gold standard for predicting persisting VA remains repeat biopsy.

Evaluating Responses to Gluten Challenge: A Randomized, Double-Blind, 2-Dose Gluten Challenge Trial.

BACKGROUND & AIMS: Gluten challenge is used to diagnose celiac disease (CeD) and for clinical research. Sustained gluten exposure reliably induces histologic changes but is burdensome. We investigated the relative abilities of multiple biomarkers to assess disease activity induced by 2 gluten doses, and aimed to identify biomarkers to supplement or replace histology. METHODS: In this randomized, double-blind, 2-dose gluten-challenge trial conducted in 2 US centers (Boston, MA), 14 adults with biopsy-proven CeD were randomized to 3 g or 10 g gluten/d for 14 days. The study was powered to detect changes in villous height to crypt depth, and stopped at planned interim analysis on reaching this end point. Additional end points included gluten-specific cluster of differentiation (CD)4 T-cell analysis with HLA-DQ2-gluten tetramers and enzyme-linked immune absorbent spot, gut-homing CD8 T cells, interleukin-2, symptoms, video capsule endoscopy, intraepithelial leukocytes, and tissue multiplex immunofluorescence. RESULTS: All assessments showed changes with gluten challenge. However, time to maximal change, change magnitude, and gluten dose-response relationship varied. Villous height to crypt depth, video capsule endoscopy enteropathy score, enzyme-linked immune absorbent spot, gut-homing CD8 T cells, intraepithelial leukocyte counts, and HLA-DQ2-restricted gluten-specific CD4 T cells showed significant changes from baseline at 10 g gluten only; symptoms were significant at 3 g. Symptoms and plasma interleukin-2 levels increased significantly or near significantly at both doses. Interleukin-2 appeared to be the earliest, most sensitive marker of acute gluten exposure. CONCLUSIONS: Modern biomarkers are sensitive and responsive to gluten exposure, potentially allowing less invasive, lower-dose, shorter-duration gluten ingestion. This work provides a preliminary framework for rational design of gluten challenge for CeD research. ClinicalTrials.gov number, NCT03409796.

Healthcare Resource Utilization and Costs in Celiac Disease: A US Claims Analysis.

INTRODUCTION: Celiac disease (CeD) is a lifelong immune-mediated enteropathy in which dietary gluten triggers an inflammatory reaction in the small intestine. This retrospective cohort study examines healthcare resource utilization (HRU) and costs between patients with CeD and matched controls. METHODS: Patients with CeD (cases) with an endoscopic biopsy and ≥2 medical encounters with a CeD diagnosis between January 1, 2010, and October 1, 2015, were identified in the MarketScan databases. The date of the first claim with a CeD diagnosis on or after the endoscopic biopsy was the index date. Cases were matched 1:1 to patients without CeD (controls) on demographic characteristics and Deyo-Charlson Comorbidity Index score. Clinical characteristics, all-cause, and CeD-related HRU and costs (adjusted to 2017 US dollars) were compared between cases and controls during the 12 months before (baseline) and 24 months after (follow-up) the index date. RESULTS: A total of 11,008 cases (mean age 40.6 years, 71.3% women) were matched to 11,008 controls. During the follow-up, a higher proportion of cases had all-cause and CeD-related HRU including inpatient admissions, emergency department visits, gastroenterologist visits, dietician visits, endoscopic biopsies, and gastroenterology imaging (all P ≤ 0.002). Incremental all-cause and CeD-related costs were in the first ($7,921 and $2,894) and second ($3,777 and $935) year of follow-up, driven by outpatient services costs. DISCUSSION: In this US national claims database analysis, there was evidence of an increase in both all-cause and CeD-related HRU and related costs in patients with CeD compared with matched patients without CeD, suggesting a significant economic burden associated with CeD.

Exposure sources, amounts and time course of gluten ingestion and excretion in patients with coeliac disease on a gluten-free diet.

BACKGROUND: A major deficit in understanding and improving treatment in coeliac disease (CD) is the lack of empiric data on real world gluten exposure. AIMS: To estimate gluten exposure on a gluten-free diet (GFD) using immunoassays for gluten immunogenic peptides (GIP) and to examine relationships among GIP detection, symptoms and suspected gluten exposures METHODS: Adults with biopsy-confirmed CD on a GFD for 24 months were recruited from a population-based inception cohort. Participants kept a diary and collected urine samples for 10 days and stools on days 4-10. 'Doggie bags' containing » portions of foods consumed were saved during the first 7 days. Gluten in food, stool and urine was quantified using A1/G12 ELISA. RESULTS: Eighteen participants with CD (12 female; age 21-70 years) and three participants on a gluten-containing diet enrolled and completed the study. Twelve out of 18 CD participants had a median 2.1 mg gluten per exposure (range 0.2 to >80 mg). Most exposures were asymptomatic and unsuspected. There was high intra-individual variability in the interval between gluten ingestion and excretion. Participants were generally unable to identify the food. CONCLUSIONS: Gluten exposure on a GFD is common, intermittent, and usually silent. Excretion kinetics are highly variable among individuals. The amount of gluten varied widely, but was typically in the milligram range, which was 10-100 times less than consumed by those on an unrestricted diet. These findings suggest that a strict GFD is difficult to attain, and specific exposures are difficult to detect due to variable time course of excretion.

Association Between Inflammatory Bowel Diseases and Celiac Disease: A Systematic Review and Meta-Analysis.

BACKGROUND & AIMS: There is controversy over the association between celiac disease (CeD) and inflammatory bowel diseases (IBD). We performed a systematic review and meta-analysis to assess evidence for an association between CeD and IBD. METHODS: We searched databases including MEDLINE, EMBASE, CENTRAL, Web of Science, CINAHL, DARE, and SIGLE through June 25, 2019 for studies assessing the risk of CeD in patients with IBD, and IBD in patients with CeD, compared with controls of any type. We used the Newcastle-Ottawa Scale to evaluate the risk of bias and GRADE to assess the certainty of the evidence. RESULTS: We identified 9791 studies and included 65 studies in our analysis. Moderate certainty evidence found an increased risk of CeD in patients with IBD vs controls (risk ratio [RR] 3.96; 95% confidence interval [CI] 2.23-7.02) and increased risk of IBD in patients with CeD vs controls (RR 9.88; 95% CI 4.03-24.21). There was low-certainty evidence for the risk of anti-Saccharomyces antibodies, a serologic marker of IBD, in patients with CeD vs controls (RR 6.22; 95% CI 2.44-15.84). There was low-certainty evidence for no difference in risk of HLA-DQ2 or DQ8 in patients with IBD vs controls (RR 1.04; 95% CI 0.42-2.56), and very low-certainty evidence for an increased risk of anti-tissue transglutaminase in patients with IBD vs controls (RR 1.52; 95% CI 0.52-4.40). Patients with IBD had a slight decrease in risk of anti-endomysial antibodies vs controls (RR 0.70; 95% CI 0.18-2.74), but these results are uncertain. CONCLUSIONS: In a systematic review and meta-analysis, we found an increased risk of IBD in patients with CeD and increased risk of CeD in patients with IBD, compared with other patient populations. High-quality prospective cohort studies are needed to assess the risk of CeD-specific and IBD-specific biomarkers in patients with IBD and CeD.

Patients over Age 75 Are at Increased Risk of Emergency Department Visit and Hospitalization Following Colonoscopy.

BACKGROUND: The age to stop screening or surveillance colonoscopy is not well established, and unplanned hospital use after colonoscopy in the elderly is not well understood. AIMS: To evaluate unplanned emergency department (ED) visits and hospitalization in patients over 75 within 7 days of outpatient colonoscopy. METHODS: In this retrospective, single-center, cohort study, we reviewed outpatient screening or surveillance colonoscopies in patients ≥ 50 in a tertiary care academic medical center or affiliated facility between January 2008 and September 2013. Colonoscopies were divided by age based on USPSTF recommendations. The rate of ED visits and hospitalizations per colonoscopy for each age-group was determined. Predictors of ED visit and hospitalization were assessed through univariate and multivariate logistic regressions, and mortality following colonoscopy was evaluated using Kaplan-Meier analysis. RESULTS: A total of 30,409 colonoscopies were performed in 27,173 patients (51% male) by 40 endoscopists. ED visits occurred after 188 colonoscopies (0.62%). Age over 75 years was independently associated with ED visit (OR 1.58, 95% CI 1.05-2.37, p = 0.027) and hospitalization (OR 3.7, 95% CI 2.03-6.73, p < 0.001) within 7 days of colonoscopy. Higher number of medication classes, recent ED visit, polypectomy, and endoscopic mucosal resection were also independent variables associated with ED utilization after procedure. The mortality rate at the end of the follow-up (median 4.4; IQR 2.7-6 years) was 1.9, 8.6, and 15.8% for the age-groups 50-75, 76-85, and > 85 years, respectively. CONCLUSION: Patients over age 75 are 1.6 times as likely to use the ED and 3.7 times as likely to be hospitalized after colonoscopy. Further prospective studies are needed to assess the risk/benefit of nondiagnostic colonoscopy in geriatric patients.