Is Gluten a Cause of Gastrointestinal Symptoms in People Without Celiac Disease?

Abstract

"The avoidance of wheat- and gluten-containing products is a worldwide phenomenon. While celiac disease is a well-established entity, the evidence base for gluten as a trigger of symptoms in patients without celiac disease (so-called 'non-celiac gluten sensitivity' or NCGS) is limited. The problems lie in the complexity of wheat and the ability of its carbohydrate as well as protein components to trigger gastrointestinal symptoms, the potentially false assumption that response to a gluten-free diet equates to an effect of gluten withdrawal, and diagnostic criteria for coeliac disease. Recent randomized controlled re-challenge trials have suggested that gluten may worsen gastrointestinal symptoms, but failed to confirm patients with self-perceived NCGS have specific gluten sensitivity. Furthermore, mechanisms by which gluten triggers symptoms have yet to be identified. This review discusses the most recent scientific evidence and our current understanding of NCGS."

[link] 

Prevalence of gluten-free diet adherence among individuals without celiac disease in the USA: results from the Continuous National Health and Nutrition Examination Survey 2009-2010.

Abstract

"OBJECTIVES:

Clinical inference suggests the prevalence of non-celiac gluten sensitivity is substantially higher than that of celiac disease in the USA. Unfortunately, there are currently no data supporting these claims. The authors analyzed nationally representative data to estimate the prevalence of adherence to agluten-free diet among participants without celiac disease and also to characterize the demographics and general health status of these participants.

STUDY DESIGN AND SETTING:

The Continuous National Health and Nutrition Examination Survey (NHANES) 2009-2010 enrolled 7762 individuals representing the civilian, non-institutionalized, US population free of celiac disease. Participants responded to interviewer administered questionnaires regarding current adherence to a gluten-free diet. Prevalence estimates were computed using SAS survey procedures.

RESULTS:

There were 49 individuals who reported current adherence to a gluten-free diet reflecting a weighted prevalence of 0.548% (95% CI 0.206-0.889). The prevalence of a gluten-free diet was higher in females (0.58%) than males (0.37%), although this was not statistically significant (p = 0.34). Participants reporting a gluten-free diet were older (46.6 vs. 40.5 years, p = 0.005), had higher high-density lipoprotein, lower iron and lower body mass index.

CONCLUSIONS:

The estimated national prevalence of non-celiac gluten sensitivity is 0.548%, approximately half that of celiac disease. Future studies are merited in order to better understand the population burden of non-celiac gluten sensitivity."

[link] 

Non-celiac gluten sensitivity: clinical relevance and recommendations for future research.

Abstract

"BACKGROUND:

There has been increasing interest in the entity of Non-Celiac Gluten Sensitivity(NCGS) in recent years; however, it still remains a controversial topic and its pathogenesis is not well understood. Celiac Disease, in contrast, is a well-studied condition that has become increasingly recognized as a prevalent condition arising from a heightened immunological response to gluten. Wheat allergy is an IgE-mediated condition capable of causing a variety of gastrointestinal symptoms. However, the number of patients who have neither celiac disease nor wheat allergy, but appear to derive benefit from a gluten-free diet, is also increasing substantially. The use of the term NCGS as a way of describing this condition has become increasingly prevalent in recent years.

PURPOSE:

In this review, we will focus on gastrointestinal manifestations of NCGS and discuss the evidence for the condition and its putative pathogenesis. We will discuss areas of controversy and areas for potential future research."

 [link]

Non-celiac gluten sensitivity: questions still to be answered despite increasing awareness.

Abstract

"Recently, the increasing number of patients worldwide who are sensitive to dietary gluten without evidence of celiac disease or wheat allergy has contributed to the identification of a new gluten-related syndrome defined as non-celiac gluten sensitivity. Our knowledge regarding this syndrome is still lacking, and many aspects of this syndrome remain unknown. Its pathogenesis is heterogeneous, with a recognized pivotal role for innate immunity; many other factors also contribute, including low-grade intestinal inflammation, increased intestinal barrier function and changes in the intestinal microbiota. Gluten and other wheat proteins, such as amylase trypsin inhibitors, are the primary triggers of this syndrome, but it has also been hypothesized that a diet rich in fermentable monosaccharides and polyols may elicit its functional gastrointestinal symptoms. The epidemiology of this condition is far from established; its prevalence in the general population is highly variable, ranging from 0.63% to 6%. From a clinical point of view, non-celiac gluten sensitivity is characterized by a wide array of gastrointestinal and extraintestinal symptoms that occur shortly after the ingestion of gluten and improve or disappear when glutenis withdrawn from the diet. These symptoms recur when gluten is reintroduced. Because diagnostic biomarkers have not yet been identified, a double-blind placebo-controlled gluten challenge is currently the diagnostic method with the highest accuracy. Future research is needed to generate more knowledge regarding non-celiac glutensensitivity, a condition that has global acceptance but has only a few certainties and many unresolved issues."

[link]