Non-Celiac Wheat Sensitivity: Permanent or Transient Condition?

Study Overview
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Brief Summary
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Non-Celiac Gluten Sensitivity (NCGS) has been recently included among the gluten-related diseases. Patients suffering from NCGS are diagnosed after carefully excluding celiac disease (CD), and immunoglobulin E (IgE)-mediated wheat allergy. Then, in the absence of sensitive and specific diagnostic biomarkers for NCGS, a monitoring of the patient during elimination and re-introduction of wheat by a double-blind placebo controlled (DBPC) challenge method has been suggested as diagnostic hallmark. Some studies seem to suggest that wheat components other than gluten can cause the symptoms, and therefore the term non-celiac wheat sensitivity (NCWS) has been proposed instead of NCGS. While it is well known that CD is a long-life condition and a strict adherence to the gluten-free diet must be maintained, it is unknown whether this is valid for NCWS. On the year 2012, the researchers published a retrospective study, including 276 patients with irritable bowel syndrome (IBS)-like symptoms who had been diagnosed with NCWS using a DBPC challenge during a ten-years period (2001-2011). The present prospective study aimed to evaluate: A) how many of these patients are still following a wheat-free diet, and B) which percentage was still suffering from NCWS, diagnosed by DBPC wheat challenge, in a subgroup of that cohort.

Detailed Description
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Non-Celiac Gluten Sensitivity (NCGS) has been recently included among the gluten-related diseases. Patients suffering from NCGS are diagnosed after carefully excluding celiac disease (CD) diagnosis by negative CD-specific serum antibodies and absence of intestinal villi atrophy, and excluding IgE-mediated wheat allergy, by negative serum specific IgE and/or skin prick test with wheat antigens. Then, in the absence of sensitive and specific diagnostic biomarkers for NCGS, a monitoring of the patient during elimination and re-introduction of wheat by a double-blind placebo controlled (DBPC) challenge method has been suggested as diagnostic hallmark. Obviously, this a cumbersome and time-consuming procedure which has been used in few studies. Despite an increasing percentage of the general population define themselves as gluten-sensitive, and by the year 2017 the market of the gluten-free products will be worth 6.6 billion of dollars, doubts persist about many aspects of NCGS. Some studies seem to suggest that wheat components other than gluten can cause the symptoms, and therefore the term non-celiac wheat sensitivity (NCWS) has been proposed instead of NCGS. Furthermore, while it is well known that CD is a long-life condition and a strict adherence to the gluten-free diet must be maintained, it is unknown whether this is valid for NCWS. On the year 2012, the researchers published a retrospective study, including 276 patients with irritable bowel syndrome (IBS)-like symptoms who had been diagnosed with NCWS using a DBPC challenge during a ten-years period (2001-2011). The present prospective study aimed to evaluate the persistence of the NCWS condition in that cohort and, consequently, the researchers estimated : A) how many of these patients are still following a wheat-free diet, and B) which percentage was still suffering from NCWS, diagnosed by DBPC wheat challenge, in a subgroup of that cohort.

Official Title
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Non-Celiac Wheat Sensitivity: Permanent or Transient Condition? A Follow-up Study

Conditions
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Non-Celiac Wheat Sensitivity

Intervention / Treatment
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* Other: Patients recruitment


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients previously diagnosed with NCWS by DBPC challenge. Exclusion Criteria: The 22 patients, included in the previous study, who tested positives for anti-endomysial antibodies (EmA) in the culture medium of the duodenal biopsies, even if the villi/crypts ratio in the duodenal mucosa was normal, were excluded from the present study.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Other: Patients recruitment|Between July and November 2016, the patients included in the previous retrospective study were contacted by phone, mail and e-mail and invited to come back to the respective clinics where they had been initially diagnosed as NCWS patients: the Department of Internal Medicine of the University Hospital of Palermo and the Department of Internal Medicine of the Hospital of Sciacca (province of Agrigento).|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| How many patients were still following a gluten-free or a wheat-free diet | A structured questionnaire was administered to evaluate how many patients were still following a gluten-free diet (GFD) and how many a wheat-free diet. | Between July and November 2016 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Evaluation of the effect of the GFD on IBS symptoms | The researchers administered a modified version of the IBS Global Assessment of Improvement (IBS-GAI) score. A responder was defined as a patient whose symptoms were either 'moderately improved' or 'substantially improved' compared with the period preceding the NCWS diagnosis. | Between July and November 2016 | 
| Evaluation of the severity of the IBS condition | The researchers administered the IBS Symptom Severity Scale (IBS-SSS), evaluating the change in total IBS-SSS score from the first evaluation (time of the NCWS diagnosis) and the follow-up evaluation (present study). A respondent was classified as a patient whose overall symptom severity on the IBS-SSS changed >50 points. | Between July and November 2016 | 
| Re-evaluation of the NCWS condition by DBPC-Wheat challenge | Finally, the repetition of the DBPC-wheat challenge will be proposed to the patients still on GFD. Those who will accept will be randomized to undergo the challenge. It will be performed with the same method used in the retrospective study. | Between July and November 2016 |