Past, Present, and Future of Noninvasive Tests to Assess Gluten Exposure, Celiac Disease Activity, and End-Organ Damage

Although many biomarkers have been proposed, and several are in widespread clinical use, there is no single readout or combination of readouts that correlates tightly with gluten exposure, disease activity, or end-organ damage in treated patients with celiac disease. Challenges to developing and evaluating better biomarkers include significant interindividual variability-related to immune amplification of gluten exposure and how effects of immune activation are manifest. Furthermore, the current "gold standard" for assessment of end-organ damage, small intestinal biopsy, is itself highly imperfect, such that a marker that is a better reflection of the "ground truth" may indeed appear to perform poorly. The goal of this review was to analyze past and present efforts to establish robust noninvasive tools for monitoring treated patients with celiac disease and to highlight emerging tools that may prove to be useful in clinical practice.

Follow-Up of Celiac Disease in Adults: "When, What, Who, and Where"

For patients with celiac disease (CeD), a lifelong gluten-free diet is not a voluntary lifestyle choice-it is a necessity. The key end points in clinical follow-up are symptom resolution, the normalization of weight, prevention of overweight, seroconversion, and negation or minimization of increased long-term morbidity. For the latter, a surrogate endpoint is mucosal healing, which means the normalization of histology to Marsh 0-1. Ideally, celiac follow-up care includes a multidisciplinary approach, effective referral processes, improved access that leverages technological advances, and following guidelines with the identification of measurable quality indicators, ideally informed by evidence-based research. Face-to-face CeD care and telemedicine are considered the standards for this process, although published data are insufficient. Guidelines and statements on diagnosis are readily available. However, data are lacking on optimal clinic visit intervals and outcomes and quality indicators such as improvement of symptoms, function and quality of life, survival and disease control, and how to most effectively use healthcare resources. The results of future research should provide the basis for general recommendations for evidence-based standards of quality of care in CeD.

A13 THE RATE OF ADVERSE EVENTS AFTER COVID-19 VACCINATION IS SIMILAR IN PATIENTS WITH CELIAC DISEASE AND NON-CELIAC POPULATION: RESULTS OF A LARGE INTERNATIONAL CROSS-SECTIONAL STUDY

Background

Patients with celiac disease (CeD) reported increased COVID-19 vaccine hesitancy due to a fear of adverse events (AEs). However, the risk of AEs post-COVID-19 vaccination in patients with CeD is unknown.

Purpose

To assess whether the rate of common side effects (SEs) and AEs due to COVID vaccines are higher in patients with CeD compared to a non-CeD population.

Method

We conducted a collaborative international cross-sectional study in 16 countries between April 2022 and July 2022. An online survey was distributed to patients with CeD through patients’ local societies, and to non-CeD from the general population in each country through social media posts, word-of-mouth, and through academic institutions. We collected data on participant demographics, medical conditions, CeD diagnosis, GFD adherence, history of COVID-19 vaccinations (type and doses) and self-reported SEs and AEs post-COVID-19 vaccine. SEs included pain/swelling at the site, fatigue, fever, chills, nausea and/or headaches. AEs included thrombosis, myocarditis, anaphylactic reaction, and hospitalization related to the vaccine. Logistic regression models were used to assess predictors such as CeD diagnosis, age, gender, vaccine type and comorbidities on the likelihood of reporting SEs and AEs post-vaccine.

Result(s)

: A total of 17,795 participants completed the survey, 13,638 with CeD (median age of 45[27]) and 4,157 non-CeD controls (median age of 43[20]). There were no significant differences in sex between CeD and controls. Overall, CeD patients had similar odds of SEs compared with non-CeD individuals (aOR=1.02;95% CI=0.92-1.14). SEs were slightly increased only in the second dose of the vaccine in the CeD population compared to non-CeD individuals (aOR= 1.35; 95% CI=1.19-1.53). The most common reported SEs in CeD and controls were pain/swelling at the injection site (29% vs 23 %, p< 0.0001) and fatigue (29% vs 24%, p<0.0001). The odds of SEs were higher with Moderna Spikevax, AstraZeneca/Oxford and Johnson and Johnson vaccines than after the Pfizer vaccine (p< 0.0001). The overall rate of AEs post-vaccine was similar between patients with CeD and non-CeD individuals (aOR= 1.29; 95% CI= 0.89-1.87). Overall, female gender, older age, GFD adherence, respiratory conditions, obesity and receiving immunosuppressive medications increased the odds of SEs, while only age and a history of allergies increased the odds of AEs.

Conclusion(s)

In this large international study, patients with CeD reported similar rates of SEs and AEs post-COVID vaccine compared to non-CeD individuals. This information is highly relevant as it addresses the main concern leading to COVID-19 vaccine hesitancy in CeD patients.

Disclosure of Interest

None Declared

A11 RISK PERCEPTION AND KNOWLEDGE OF COVID-19 IN PATIENTS WITH CELIAC DISEASE

Background

Celiac disease (CeD) has been associated with an increased risk of respiratory infections, however, we recently demonstrated that the odds of contracting COVID-19 in patients with CeD is similar to that of the general population. Due to this discrepancy, how patients with CeD perceive their risk may differ from their actual risk.

Aims

The aim of this study was to investigate the risk perceptions for contracting COVID-19 in patients with CeD and to determine the factors that may influence their perceptions.

Methods

We distributed a survey throughout 10 countries between March and June 2020 and collected data on demographics, diet, COVID-19 testing, and risk perceptions of COVID-19 in patients with CeD. Participants were recruited through various celiac associations, clinic visits, and social media. Risk perception was assessed by asking individuals whether they believe patients with CeD are at an increased risk of contracting COVID-19 compared to the general population. Logistic regression was used to determine the influencing factors associated with COVID-19 risk perception, such as age, sex, adherence to a gluten-free diet (GFD), and comorbidities such as cardiac/respiratory conditions and diabetes. Data was presented as adjusted odds ratios (aORs).

Results

A total of 10,737 participants with CeD completed the survey. From them, 6,019 (56.1%) patients with CeD perceived they were at a higher risk or were unsure if they were at a higher risk of contracting COVID-19 compared to the non-CeD population. A greater proportion of patients with CeD had high levels of COVID-19 risk perceptions when compared to infections in general (56.1% vs 26.7%; p<0.0001). Consequently, 28.8% reported taking extra COVID-19 precautions as a result of their CeD. Members of celiac associations had lower rates of perceiving an increased risk of COVID-19 when compared to non-members (49.5% vs 57.4%, p<0.0001). Older age (aOR: 0.9; 95% CI: 0.9 to 1, p<0.001), male sex (aOR: 0.85; 95% CI: 0.76 to 0.94, p=0.001), and strict adherence to a GFD (aOR: 0.89; 95% CI 0.82 to 0.97, p=0.007) were associated with a lower perception of COVID-19 risk. Meanwhile, the presence of comorbidities was associated with a higher perception of COVID-19 risk (aOR: 1.34; 95% CI: 1.20 to 1.51, p<0.001).

Conclusions

Overall, a large proportion of patients with CeD, particularly females, those with comorbidities, or those not adhering to a strict GFD, believed they were or were unsure if they were at a higher risk of contracting COVID-19 due to their condition. As high levels of risk perception may increase an individual’s pandemic-related stress and contribute to negative mental health consequences, healthcare providers should maintain consistent communication with the celiac community and provide them with evidence-based recommendations.

Funding Agencies

None

The Risk of Contracting COVID-19 Is Not Increased in Patients With Celiac Disease

The World Health Organization declared coronavirus disease-2019 (COVID-19) a global pandemic in March 2020. Since then, there are more than 34 million cases of COVID-19 leading to more than 1 million deaths worldwide. Numerous studies suggest that celiac disease (CeD), a chronic immune-mediated gastrointestinal condition triggered by gluten, is associated with an increased risk of respiratory infections.^1-3 However, how it relates to the risk of COVID-19 is unknown. To address this gap, we conducted a cross-sectional study to evaluate whether patients with self-reported CeD are at an increased risk of contracting COVID-19.

Iron deficiency

Iron deficiency is one of the leading contributors to the global burden of disease, and particularly affects children, premenopausal women, and people in low-income and middle-income countries. Anaemia is one of many consequences of iron deficiency, and clinical and functional impairments can occur in the absence of anaemia. Iron deprivation from erythroblasts and other tissues occurs when total body stores of iron are low or when inflammation causes withholding of iron from the plasma, particularly through the action of hepcidin, the main regulator of systemic iron homoeostasis. Oral iron therapy is the first line of treatment in most cases. Hepcidin upregulation by oral iron supplementation limits the absorption efficiency of high-dose oral iron supplementation, and of oral iron during inflammation. Modern parenteral iron formulations have substantially altered iron treatment and enable rapid, safe total-dose iron replacement. An underlying cause should be sought in all patients presenting with iron deficiency: screening for coeliac disease should be considered routinely, and endoscopic investigation to exclude bleeding gastrointestinal lesions is warranted in men and postmenopausal women presenting with iron deficiency anaemia. Iron supplementation programmes in low-income countries comprise part of the solution to meeting WHO Global Nutrition Targets.

Relations between symptom severity, illness perceptions, visceral sensitivity, coping strategies and well-being in irritable bowel syndrome guided by the common sense model of illness

Irritable Bowel Syndrome (IBS) is a common condition affecting around 10-20% of the population and associated with poorer psychological well-being and quality of life. The aim of the current study was to explore the efficacy of the Common Sense Model (CSM) using Structural Equation Modelling (SEM) in an IBS cohort. One hundred and thirty-one IBS patients (29 males, 102 females, mean age 38 years) participating in the IBSclinic.org.au pre-intervention assessment were included. Measures included IBS severity (Irritable Bowel Syndrome Severity Scoring System), coping patterns (Carver Brief COPE), visceral sensitivity (Visceral Sensitivity Index), illness perceptions (Brief Illness Perceptions Questionnaire), psychological distress (Depression, Anxiety and Stress Scale), and quality of life (IBS Quality of Life scale; IBS-QoL). Using SEM, a final model with an excellent fit was identified (χ² (8) = 11.91, p = .16, χ²/N = 1.49, CFI > .98, TLI > .96, SRMR < .05). Consistent with the CSM, Illness perceptions were significantly and directly influenced by IBS severity (β = .90, p < .001). Illness perceptions in turn directly influenced maladaptive coping (β = .40, p < .001) and visceral sensitivity (β = .70, p < .001). Maladaptive coping and visceral sensitivity were significantly associated with psychological distress (β = .55, p < .001; β = .22, p < .01) and IBS-QoL (β = -.28, p < .001; β = -.62, p < .001). Based on these findings, we argue that to augment the adverse impact of IBS severity on IBS-QoL and psychological distress, psychological interventions will be best to target the mediating psychological processes including illness beliefs, visceral sensitivity and maladaptive coping.

Immunopathogenesis of celiac disease

Celiac disease is a chronic inflammatory disease caused by dietary gluten that affects 1% of Europeans and North Americans. Gluten is unusual because it is consumed in relatively large amounts, is partially resistant to luminal digestion in the human small intestine, and when absorbed, is susceptible to post-translational modification (deamidation) by mucosal transglutaminase. Deamidation of certain gluten peptides enhances their binding to HLA-DQ2 or HLA-DQ8 and creates neodeterminants capable of stimulating CD4+ T cells. Only 5% of individuals with HLA-DQ2 and 0.5% of those with HLA-DQ8 have celiac disease, so immuno-logic tolerance to gluten is the norm. The critical steps in the immunopathogenesis of celiac disease are broadly understood, but little is known regarding mechanisms of tolerance to gluten. The effectiveness of therapies being developed for celiac disease will test the accuracy of our current understanding of disease pathogenesis.

Aspiration in the context of upper gastrointestinal endoscopy

BACKGROUND

Pulmonary aspiration is a life-threatening complication of upper gastrointestinal endoscopy, the incidence of which has not been determined. Endoscopy-related aspiration has not been studied in procedures in which patients swallow a radiolabelled potential aspirate immediately before endoscopy and undergo nuclear scanning postprocedure.

METHODS

A pilot study was conducted in which 200 MBq of nonabsorbable technetium-99m phytate in 10 mL of water was administered orally to 50 patients who were about to undergo endoscopy. Gamma camera images were obtained to ensure that there had been no aspiration before endoscopy. After endoscopy, a repeat scan was performed. Fluid aspirated through the endoscope was also collected and analyzed for radioactivity using a hand-held radiation monitor.

RESULTS

No evidence of pulmonary aspiration was found in any of the patients studied. The mean estimated percentage of the initially administered radioactivity aspirated through the endoscope was 2.66% (range 0% to 10.3%).

CONCLUSION

The present pilot study confirms earlier observations that clinically significant aspiration in the context of upper gastrointestinal endoscopy is uncommon. The incidence of aspiration may, however, be different in acutely bleeding patients undergoing endoscopy. For logistic reasons, this group could not be studied.