Development of the Dietitian Integrated Evaluation Tool for Gluten-free Diets (DIET-GFD)

Development and Validation of a Tool for Assessing Adherence to Gluten-Free Diet in Patients With Celiac Disease

INTRODUCTION

Life-long adherence to gluten-free diet (GFD) and its assessment is essential for patients with celiac disease (CeD). We have developed and validated a tool for assessing adherence to GFD which can be used by both physicians and dietitians.

METHODS

Phase 1: Development, content validation, and assessment of reliability of tool. Phase 2: Validation of tool against standard dietary evaluation (SDE) (gold standard), immunoglobulin A - anti-tissue transglutaminase antibodies (IgA anti-tTG Ab), and gluten immunogenic peptides in urine. Overall, 380 biopsy-confirmed patients with CeD (derivation cohort: n = 100 [phase 1], n = 210 [phase 2] and independent validation cohort, n = 70) were recruited.

RESULTS

Of an initial 90-point questionnaire, 84 items (Celiac Disease: Compliance Assessment Test [CD-CAT.v1]) were retained after content validation and pilot testing. In phase 1, upon administering CD-CAT.v1 on 100 patients, a comprehensive 35-item tool (CD-CAT.v2; α = 0.86) was obtained after removing items with low test-retest reliability and item-rest correlation values. In phase 2, upon administering CD-CAT.v2 on 210 patients, 22 items were removed having low correlation values (R < 0.4) with SDE. Finally, a 13-item tool (CD-CAT.v3; α = 0.84) was obtained with high criterion validity with SDE ( r = 0.806, P < 0.001), moderate convergent validity with celiac disease adherence test ( r = 0.602, P = 0.007), and moderate to weak correlation with urine gluten immunogenic peptides ( r = 0.46, P = 0.001) and IgA anti-tTG Ab ( r = 0.39, P = 0.008), respectively. The final 13-item tool also strongly correlated with SDE ( r = 0.78, P < 0.001) in an independent validation cohort of 70 patients with CeD. Principal component analysis identified 3 relevant subscales with a cumulative variance of 62%. The sensitivity and specificity of CD-CAT.v3 were 80% and 91%, respectively, with an area under curve of 0.905 with SDE. The obtained cutoff score of <19 from the receiver operating characteristic curve was further categorized as 13 = excellent, 14-18 = very good, 19-28 = average, and >28 = poor adherence to GFD.

DISCUSSION

CD-CAT is a new and rapid tool for monitoring dietary adherence to GFD with high sensitivity and specificity, which can be administered by both physicians and dietitians.

Dietary adherence is not dependent on the mode of diagnosis in children with coeliac disease

AIM

To compare the adherence to gluten-free diet between children with serology-based and biopsy-proven coeliac disease.

METHODS

Medical records were retrospectively reviewed in 257 Swedish children diagnosed with coeliac disease between 2012 and 2019 at a tertiary hospital. Adherence to a gluten-free diet was systematically assessed by trained dietitians at follow-up. Mixed models were used to analyse the dietary adherence by mode of diagnosis (serology-based vs. biopsy-proven).

RESULTS

After mean 6.3 (SD 2.4) years, there was neither a difference in the dietary adherence over time depending on the mode of diagnosis (OR 0.64 [95% confidence interval (CI) 0.26, 1.60], p = 0.342), nor if coeliac disease was detected in screening studies (OR 0.74 [95% CI 0.25, 2.17], p = 0.584) or in risk-groups (OR 1.01 [95% CI 0.26, 3.91], p = 0.991) compared to clinically detected diagnosis. Non-adherence to a gluten-free diet increased with age (OR 1.19 [95% CI 1.06, 1.33], p = 0.003). There was no difference in the proportion of patients improving their dietary adherence from non-adherent to adherent over time (p = 0.322).

CONCLUSION

Mode of diagnosis did not influence the dietary adherence in Swedish children with coeliac disease, although adherence to a gluten-free diet was inversely associated with increasing age.

Gluten-Free Diet Adherence Tools for Individuals with Celiac Disease: A Systematic Review and Meta-Analysis of Tools Compared to Laboratory Tests

This systematic review aimed to find the tool that best predicts celiac individuals' adherence to a gluten-free diet (GFD). The Transparent Reporting of Multivariable Prediction Models for Individual Prognosis or Diagnosis (TRIPOD-SRMA) guideline was used for the construction and collection of data from eight scientific databases (PubMed, EMBASE, LILACS, Web of Science, LIVIVO, SCOPUS, Google Scholar, and Proquest) on 16 November 2023. The inclusion criteria were studies involving individuals with celiac disease (CD) who were over 18 years old and on a GFD for at least six months, using a questionnaire to predict adherence to a GFD, and comparing it with laboratory tests (serological tests, gluten immunogenic peptide-GIP, or biopsy). Review articles, book chapters, and studies without sufficient data were excluded. The Checklist for Critical Appraisal and Data Extraction for Systematic Reviews of Prediction Modeling Studies (CHARMS) was used for data collection from the selected primary studies, and their risk of bias and quality was assessed using the Prediction Risk of Bias Assessment Tool (PROBAST). The association between the GFD adherence determined by the tool and laboratory test was assessed using the phi contingency coefficient. The studies included in this review used four different tools to evaluate GFD adherence: BIAGI score, Coeliac Dietary Adherence Test (CDAT), self-report questions, and interviews. The comparison method most often used was biopsy (n = 19; 59.3%), followed by serology (n = 14; 43.7%) and gluten immunogenic peptides (GIPs) (n = 4; 12.5%). There were no significant differences between the interview, self-report, and BIAGI tools used to evaluate GFD adherence. These tools were better associated with GFD adherence than the CDAT. Considering their cost, application time, and prediction capacity, the self-report and BIAGI were the preferred tools for evaluating GFD adherence.

Nutrition Assessment and Management in Celiac Disease

Celiac disease (CeD) is the most common immune condition affecting the gastrointestinal tract; it is triggered by gluten and the only available treatment is a strict gluten-free diet (GFD). Therefore, for patients with CeD, adopting a GFD is not a lifestyle choice. The major problem is that a GFD is restrictive and, like all restrictive diets, it has the potential for adverse nutritional outcomes, especially if adopted for a long term. It is well known that GFD can be nutritionally inadequate and is frequently associated with vitamin and mineral deficiencies; it is also associated with excessive sugar and fat intake, particularly when gluten-free substitutes are consumed. Consequently, people with CeD are affected by higher rates of overweight and obesity and metabolic complications, such as fatty liver and cardiovascular disease. Therefore, assessment of nutritional status and diet quality at diagnosis and while on a long-term GFD is key in the management of CeD. This narrative review addresses nutritional considerations in CeD and management of common challenges associated with a GFD.

Gluten-free diet for pediatric patients with coeliac disease: A position paper from the ESPGHAN gastroenterology committee, special interest group in coeliac disease

BACKGROUND AND OBJECTIVE

Coeliac disease is a chronic, immune-mediated disorder for which the only treatment consists of lifelong strict adherence to gluten-free diet (GFD). However, there is a lack of evidence-based guidelines on the GFD dietary management of coeliac disease. This position paper, led by the Special Interest Group in coeliac disease of the European Society of Pediatric, Gastroenterology Hepatology, and Nutrition, supported by the Nutrition Committee and the Allied Health Professionals Committee, aims to present evidence-based recommendations on the GFD as well as how to support dietary adherence.

METHODS

A wide literature search was performed using the MeSH Terms: "diet, gluten free," "gluten-free diet," "diets, gluten-free," "gluten free diet," and "coeliac disease" in Pubmed until November 8th, 2022.

RESULTS

The manuscript provides an overview of the definition of the GFD, regulations as basis to define the term "gluten-free," which foods are naturally gluten-free and gluten-containing. Moreover, it provides recommendations and educational tips and infographics on suitable food substitutes, the importance of reading food labels, risk of gluten cross-contact at home and in public settings, nutritional considerations as well as factors associated to dietary adherence based on available evidence, or otherwise clinical expertise.

CONCLUSIONS

This position paper provides guidance and recommendations to support children with coeliac disease to safely adhere to a GFD.

Guidelines for best practices in monitoring established coeliac disease in adult patients

Coeliac disease (CeD) is an immunological disease triggered by the consumption of gluten contained in food in individuals with a genetic predisposition. Diagnosis is based on the presence of small bowel mucosal atrophy and circulating autoantibodies (anti-type 2 transglutaminase antibodies). After diagnosis, patients follow a strict, life-long gluten-free diet. Although the criteria for diagnosis of this disease are well defined, the monitoring phase has been studied less and there is a lack of specific guidelines for this phase. To develop a set of clinical guidelines for CeD monitoring, we followed the Grading of Recommendations Assessment, Development and Evaluation methodology. Statements and recommendations with the level of evidence were developed and approved by the working group, which comprised gastroenterologists, pathologists, dieticians and biostatisticians. The proposed guidelines, endorsed by the North American and European coeliac disease scientific societies, make recommendations for best practices in monitoring patients with CeD based on the available evidence. The evidence level is low for many topics, suggesting that further research in specific aspects of CeD would be valuable. In conclusion, the present guidelines support clinicians in improving CeD treatment and follow-up and highlight novel issues that should be considered in future studies.

The Gluten-Free Diet for Celiac Disease: Critical Insights to Better Understand Clinical Outcomes

The gluten-free diet (GFD) remains a complex paradigm in managing celiac disease (CeD) in children and adults, and there are many reasons why GFD adherence should be strict to improve outcomes. However, this is a challenging task for patients, since they need to have access to quality healthcare resources that facilitate optimal GFD adherence. Understanding the strengths and weaknesses of the GFD, tackling coexisting nutritional deficiencies, and dealing with complex situations, such as seronegative CeD or non-responsive CeD, all require the involvement of a multidisciplinary team. The short- and long-term follow-up of CeD patients should preferably be performed by a combined Gastroenterology and Nutrition service with well-defined quality standards and the multidisciplinary involvement of physicians, nurses, dietitians, and psychologists. Nutritional advice and counseling by an experienced dietitian can reduce the costs associated with long-term follow-up of CeD patients. Likewise, psychological interventions may be essential in specific scenarios where implementing and sustaining a lifelong GFD can cause a significant psychological burden for patients. This manuscript aims to provide guidelines to improve clinical practice in the follow-up and monitoring of CeD patients and provide information on the nutritional risks of an ill-advised GFD. Clinicians, biochemists, food technologists, dietitians, and psychologists with a global view of the disease have been involved in its writing.

Predictors of adherence to a gluten-free diet in celiac disease: Do knowledge, attitudes, experiences, symptoms, and quality of life play a role?

OBJECTIVES

This study aimed to identify the relationship between adherence to a gluten-free diet (GFD) and demographic characteristics, knowledge, attitudes, and beliefs regarding celiac disease (CD) and GFD, experiences of following a GFD, symptoms, and quality of life (QoL).

METHODS

Patients with CD were recruited from outpatient clinics. Adherence to GFD was assessed using the CD adherence test (CDAT) and GFD score (GFD-S). Knowledge, attitudes, experiences, symptoms, and QoL were assessed using existing questionnaires. A multivariate logistic regression was performed.

RESULTS

Overall, 116 patients with CD were included (48 ± 16 y; 70% female). Based on the CDAT, 58 patients (50%) were adequate adherers, but 86 patients (74%) were adequate adherers according to GFD-S. When adherence was measured using the CDAT, being female was associated with lower odds of adherence (odds ratio [OR]: 0.36; P = 0.028), and better emotional wellbeing was associated with higher odds of adherence (OR: 1.19; P < 0.001). When adherence was measured using GFD-S, membership in a support group (OR: 6.17; P = 0.002), stronger beliefs about the chronicity of CD (OR: 1.15; P = 0.059), and weaker beliefs on accident/chance causing CD (OR: 1.94; P = 0.05) were associated with greater odds of adherence. Difficulties when eating with family/friends (OR: 0.98; P = 0.005) and weaker beliefs on immunity causing CD (OR: 0.77; P = 0.031) were associated with lower odds of adherence.

CONCLUSIONS

The association between gender, attending support groups, attitudes, experiences, and QoL with adherence to a GFD should be considered by health care professionals managing patients with CD.

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 ¼ 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.