Characteristics of patients who avoid wheat and/or gluten in the absence of Celiac disease

Gluten-related Disorders From Bench to Bedside

Celiac disease, non-celiac gluten sensitivity, and wheat allergy comprise 3 of the main conditions with wheat- and gluten-containing foods as the symptom trigger. Distinguishing between these entities can be daunting. In this review, we compare and contrast celiac disease, non-celiac gluten sensitivity, and wheat allergy to allow clinicians to determine which diagnosis fits their patient to facilitate high-quality management and longitudinal care.

Investigation of the Factors Affecting Bone Mineral Density in Children with Celiac Disease

PURPOSE

Children with celiac disease (CD) are at an increased risk of low bone mineral density (BMD) owing to malabsorption of fat-soluble vitamins, inflammation, and malnutrition. This study aimed to determine the prevalence and risk factors for low BMD in Iranian children with CD.

METHODS

This prospective cohort study examined 149 Iranian children with CD between 2011 and 2018 at Zabol University of Medical Sciences. BMD was measured using dual-energy X-ray absorptiometry. Demographic, clinical, and laboratory data were collected from patients' medical records. Logistic regression analysis was performed to identify the factors associated with low areal BMD (BMD-Z <-2) in the lumbar spine and femoral neck. Descriptive data were analyzed using the mean, standard deviation, and relative frequency. Data were analyzed using the chi-square test, t-test, and analysis of variance.

RESULTS

Of the 149 children with CD, 27.5% had osteoporosis. The mean body mass index (BMI) Z score was -1.28±1.2. Lower BMI was associated with a higher likelihood of BMD-Z (odds ratio 2.17; p≤0.05).

CONCLUSION

Overall, the findings of this study showed that there was no correlation among Marsh classification, presence of specific human leukocyte antigens, and low BMD in Iranian children with CD. BMI can be a predictor of bone density in children with CD and may be applied clinically in early screenings to evaluate the bone health status in these children.

Self-reported nonceliac wheat sensitivity in an outpatient digestive endoscopy center: high frequency but insufficient medical approach

OBJECTIVE

'Self-reported wheat sensitivity' (SRWS) is a self-reported condition caused by wheat ingestion in the absence of celiac disease or wheat allergy. The aim of the study was to investigate the frequency and characteristics of SRWS in outpatients referred for digestive endoscopy.

METHODS

The study, performed at the University of Palermo, enrolled 496 outpatients.

RESULTS

Seven individuals (1.4%) had an already established diagnosis of celiac disease. The questionnaire was administered to the other 489 individuals: 98 subjects (20%) were SRWS, the remaining 391 served as controls (i.e. not-SRWS). SRWS patients were younger (P < 0.001), with a higher percentage of females (P = 0.002) than not-SRWS. 'gastroesophageal reflux disease and ulcer-like dyspepsia' and 'chronic unexplained diarrhea' were more frequently the reasons for the endoscopy study in SRWS than in not-SRWS (P = 0.002, and P = 0.05, respectively). Food allergies/intolerances (P = 0.04), milk allergy/intolerance (P = 0.0001), GERD (P = 0.0001), IBS (0.0001), anxiety (P = 0.005) and depression (P = 0.04) were the previous medical diagnoses reported more frequently in SRWS patients than in not-SRWS. In the SRWS group, 38% of the patients had already undergone previous upper endoscopy and 24% colonoscopy. After these investigations, 58% of SRWS patients received no diagnosis, and the other 42% were informed that they 'were not suffering from celiac disease or wheat allergy'. Finally, 28.6% SRWS patients had followed a gluten-free diet (GFD), and 71.4% of them referred being asymptomatic on GFD.

CONCLUSIONS

Our data showed a high frequency of SRWS in outpatients referred to a digestive endoscopy center and a lack of medical accuracy in identifying a possible gluten-related disease.

REGISTRATION

The study was registered on Clinicaltrials.gov (registration number: NCT04154137), accessible at: https://clinicaltrials.gov/ct2/show/NCT04154137?term=non+celiac+wheat&draw=2&rank=1.

"The Gluten-Free Diet and Its Relationship with Metabolic Syndrome: Dietary Friend or Foe?"

PURPOSE OF REVIEW

Celiac disease (CD) is a prevalent digestive illness as well as a budding area of research in the field of gastroenterology. While investigations are underway to find new and improved pharmacological therapies for CD, the gluten-free diet (GFD) remains the only option to effectively manage the condition.

RECENT FINDINGS

While the GFD is recommended for patients diagnosed with CD and other gluten-related conditions, studies show the number of individuals on the GFD surpasses the projected number of patients with these medical indications (1). The implications of widespread adoption of this dietary approach are still being determined, with many patients believing this diet will improve overall health and cardiovascular risk. This review analyzes the relationship between a GFD and metabolic syndrome in both non-celiac and celiac patients, concluding that although the diet may slightly improve overall cardiac risk factors, weight, and/or insulin resistance, its use in the absence of a gluten-related disorder is controversial.

Non-Celiac Gluten Sensitivity in the Context of Functional Gastrointestinal Disorders

Gluten-free diets are increasingly chosen in the Western world, even in the absence of a diagnosis of celiac disease. Around 10% of people worldwide self-report gluten-related complaints, including intestinal and extra-intestinal symptoms. In most cases, these subjects would be labeled as patients suffering from irritable bowel syndrome (IBS) who place themselves on a gluten-free diet even in the absence of celiac disease. In some instances, patients report a clear benefit by avoiding gluten from their diet and/or symptom worsening upon gluten reintroduction. This clinical entity has been termed non-celiac gluten sensitivity (NCGS). The symptoms referred by these patients are both intestinal and extra-intestinal, suggesting that similarly to functional gastrointestinal disorders, NCGS is a disorder of gut-brain interaction. It remains unclear if gluten is the only wheat component involved in NCGS. The mechanisms underlying symptom generation in NCGS remain to be fully clarified, although in the past few years, the research has significantly moved forward with new data linking NCGS to changes in gut motility, permeability and innate immunity. The diagnosis is largely based on the self-reported reaction to gluten by the patient, as there are no available biomarkers, and confirmatory double-blind challenge protocols are unfeasible in daily clinical practice. Some studies suggest that a small proportion of patients with IBS have an intolerance to gluten. However, the benefits of gluten-free or low-gluten diets in non-celiac disease-related conditions are limited, and the long-term consequences of this practice may include nutritional and gut microbiota unbalance. Here, we summarize the role of gluten in the clinical features, pathophysiology, and management of NCGS and disorders of gut-brain interaction.

Characteristics and Maternal-Fetal Outcomes of Pregnant Women Without Celiac Disease Who Avoid Gluten

BACKGROUND

Gluten avoidance among patients without celiac disease has become increasingly popular, especially among young and female demographics; however, no research has explored gluten avoidance during pregnancy, when nutrition is particularly important.

AIMS

To determine whether avoiding gluten in pregnancy is associated with any medical, obstetric, or neonatal characteristics.

METHODS

In this single-center retrospective cohort study, we identified women with singleton pregnancies who avoid gluten based on antenatal intake questionnaire responses and inpatient dietary orders, excluding those with celiac disease. Certain demographic, medical, obstetric, and neonatal characteristics were compared to matched controls who do not avoid gluten.

RESULTS

From July 1, 2011 to July 1, 2019, 138 pregnant women who avoid gluten were admitted for delivery of singleton gestations. Compared to controls, gluten-avoidant women had fewer prior pregnancies (p = 0.005), deliveries (p < 0.0005), and living children (p < 0.0005), higher rates of hypothyroidism (OR = 3.22; p = 0.001) and irritable bowel syndrome (OR = 6.00; p = 0.019), higher second trimester hemoglobin (p = 0.018), and lower body mass index at delivery (p = 0.045). Groups did not differ in any obstetric or fetal characteristics.

CONCLUSIONS

Gluten avoidance in pregnancy is common and, in women without celiac disease, is associated with higher rates of hypothyroidism and irritable bowel syndrome, fewer pregnancies, term births, and living children, and lower peripartum BMI, but is not associated with any obstetric or neonatal comorbidities. Avoiding gluten does not appear to adversely affect maternal or fetal health, but reasons for gluten avoidance, as well as long-term maternal and pediatric outcomes after gluten avoidance in pregnancy, warrant further study.

Autoimmune and Allergic Disorders are More Common in People With Celiac Disease or on a Gluten-free Diet in the United States

GOALS

We analyzed demographics, lifestyle patterns, and clinical characteristics of people with celiac disease (CD) and people without CD avoiding gluten (PWAG) to better understand associations with medical conditions and consumer behavior.

BACKGROUND

Clinical significance of CD and gluten avoidance in the general population is incompletely understood. Recently, a high incidence of CD in adolescents with susceptibility genotypes, similar to other autoimmune or allergic disorders, and regional differences in consumer practices of gluten avoidance were reported.

METHODS

Among 22,277 participants in the National Health and Nutrition Examination Survey 2009-2014, we identified persons with CD by testing CD serology or by both a health care provider diagnosis and adherence to a gluten-free diet. Similarly, PWAG were defined as adherent to a gluten-free diet without a CD diagnosis. Consumer behavior and characteristics of both groups, CD and PWAG were compared with those without these conditions, using survey-weighted generalized logistic regression.

RESULTS

Participants with CD considered nutrition very important when grocery shopping and tended to have more constipation and thyroid disease. PWAG tended to spend more money on groceries, purchase organic foods, and check food labels more frequently during grocery shopping. They also reported having more food allergies, asthma, and thyroid disease.

CONCLUSIONS

Our study confirms that CD and PWAG share comorbidities of autoimmune nature. PWAG had more autoimmune/allergy-related disorders that may be associated with non-celiac gluten sensitivity a self-justifiable reason to be on the diet.

Going Against the Grains: Gluten-Free Diets in Patients Without Celiac Disease-Worthwhile or Not?

While the gluten-free diet (GFD) is the only known effective therapy for celiac disease, in recent years it has become increasingly popular in the USA and worldwide, with many believing it to be more "healthful" and others claiming that it has beneficial effects for health conditions, many extraintestinal, other than celiac disease. This review examines the evidence for use of the GFD in patients without celiac disease who self-report intestinal and/or extraintestinal symptoms (non-celiac gluten sensitivity), as well as for enhancement of athletic performance and treatment of autism, rheumatoid arthritis, and psychiatric disorders. Overall, the evidence for use of GFDs in conditions other than celiac disease is poor. Though non-celiac gluten sensitivity may ultimately emerge as a biomarker-defined condition, a large proportion of patients with apparent non-celiac gluten sensitivity have, after careful investigation, an alternative diagnosis. In light of this, and coupled with the potential physical and psychological harms associated with the avoidance of gluten, initiating a GFD should not be encouraged for people who have these other conditions or are seeking physical/athletic enhancement.

Gluten-free diet in French adults without coeliac disease: sociodemographic characteristics, motives and dietary profile

The number of people avoiding gluten is growing in many Western countries. However, little information is available on their sociodemographic and dietary profiles. We aimed to describe sociodemographic, behavioural and dietary profiles of participants avoiding gluten in the NutriNet-Santé cohort. Participants of the NutriNet-Santé cohort – excluding coeliac patients – who completed a questionnaire about food exclusions, with complete data on sociodemographic characteristics and dietary intake were included (n 20 456). Food group consumptions and nutrient intakes according to self-reported avoidance of gluten were estimated using ANCOVA adjusted for age, sex and daily energy intake. Based on principal component analysis, three dietary patterns (DP) were identified. Association between DP and avoidance of gluten was investigated using multivariate logistic regression. All data were weighted on the French census. A total of 10·31 (95 % CI 9·90, 10·73) % of the participants declared avoiding gluten, of which 1·65 % totally. They were more likely to be women, older persons, non-smokers, to have a lower educational level and declared more food intolerances. They had higher consumption of fruit, vegetables and lower consumption of dairy products, salty/sweet and fatty foods and alcohol. After adjustments on confounders, a healthy dietary pattern was positively associated with total gluten avoidance (ORQuintile5vsQuintile1 = 14·44, 95 % CI 8·62, 24·19). Our study highlighted that, in this population, individuals who avoid gluten from their diet tend to have a diet more favourable to health. These results can serve as a basis for future studies investigating the potential consequences of a gluten-free diet in non-coeliac population.

Duodenal and Rectal Mucosa Inflammation in Patients With Non-celiac Wheat Sensitivity

BACKGROUND & AIMS

Studies of non-celiac gluten or wheat sensitivity (NCGWS) have increased but there are no biomarkers of this disorder. We aimed to evaluate histologic features of colon and rectal tissues from patients with NCGWS.

METHODS

We performed a prospective study of 78 patients (66 female; mean age, 36.4 years) diagnosed with NCGWS by double-blind wheat challenge at 2 tertiary care centers in Italy, from January 2015 through September 2016. Data were also collected from 55 patients wither either celiac disease or self-reported NCGWS but negative results from the wheat-challenge test (non-NCGWS controls). Duodenal and rectal biopsies were collected and analyzed by immunohistochemistry to quantify intra-epithelial CD3+ T cells, lamina propria CD45+ cells, CD4+ and CD8+ T cells, mast cells, and eosinophils and to determine the presence and size of lymphoid nodules in patients with NCGWS vs patients with celiac disease or non-NCGWS controls.

RESULTS

Duodenal tissues from patients with NCGWS had significantly higher numbers of intra-epithelial CD3+ T cells, lamina propria CD45+ cells, and eosinophils than duodenal tissues from non-NCGWS controls. Duodenal tissues from patients with NCGWS and dyspepsia had a higher number of lamina propria eosinophils than patients with NCGWS without upper digestive tract symptoms. Rectal mucosa from patients with NCGWS had a larger number of enlarged lymphoid follicles, intra-epithelial CD3+ T cells, lamina propria CD45+ cells, and eosinophils than rectal mucosa from non-NCGWS controls. Duodenal and rectal mucosal tissues from patients with celiac disease had more immunocytes (CD45+ cells, CD3+ cells, and eosinophils) than tissues from patients with NCGWS or non-NCGWS controls.

CONCLUSIONS

We identified markers of inflammation, including increased numbers of eosinophils, in duodenal and rectal mucosa from patients with NCGWS. NCGWS might therefore involve inflammation of the entire intestinal tract. Eosinophils could serve as a biomarker for NCGWS and be involved in its pathogenesis. Clinicaltrials.gov: NCT01762579.

The Effect of Gluten Free Diet on Components of Metabolic Syndrome: A Randomized Clinical Trial

Background: This study aimed to assess the effects of Gluten free diet (GFD) on components of metabolic syndrome (MES). Materials and Methods: In this randomized clinical trial, 50 subjects diagnosed with MES were randomly divided into two groups (n=25). The first group received a GFD and the second group continued their regular diet. Biochemical markers of MES and blood pressure were measured before and after 8-week intervention. Results: Forty five subjects completed the study. A post-hoc comparison of the groups showed no effects of the GFD and control diet on LDL cholesterol, total cholesterol, fasting insulin, HOMA-IR, systolic and diastolic blood pressure levels. The GFD reduced fasting blood glucose, waist circumference (WC) and serum triglyceride concentration significantly compared with the control diet (p<0.05). Conclusion: Short-term GFD reduced WC and improved glycemic control and Triglyceride level in subjects with the metabolic syndrome.

Regional and National Variations in Reasons for Gluten Avoidance

BACKGROUND

Although studies have assessed the prevalence of celiac disease (CD), less is known about the prevalence of gluten avoidance because of nonceliac gluten sensitivity (GS). The avoidance of foods other than gluten is also understudied in these 2 groups.

METHODS

Participants visiting a web site for information about a newly developed portable gluten detection device (Nima) were instructed to complete questions about food and gluten avoidance patterns. We assessed the relative proportion of CD and GS across world regions and United States (US) regions and determined the distribution of food avoidance patterns.

RESULTS

CD was reported in 6474 respondents and GS in 2597 respondents. Within the United States, the majority of avoiders of gluten reported having CD (69.8%), with the highest ratio of CD to GS in the Northeast (CD: 74.3%; GS: 25.7%) and the lowest in the West (CD: 67.1%; GS: 32.9%) (P<0.0001). Compared with the United States, all other countries had lower proportions of GS, with the lowest in Argentina (CD: 94.7%; GS: 5.3%; P<0.0001). Food avoidances other than gluten were reported by 25% of respondents, with avoidance in all categories more common in GS than CD (P<0.0001).

CONCLUSION

There is a significant difference in the relative rates of CD and GS within the United States and worldwide. Food avoidance other than gluten seems to be a more common component of GS than CD. Future research should focus on the causes of these international and US regional differences and the significance of other food avoidances.

Skepticism Regarding Vaccine and Gluten-Free Food Safety Among Patients with Celiac Disease and Non-celiac Gluten Sensitivity

BACKGROUND

There has been a marked increase in the adoption of the gluten-free (GF) diet.

AIMS

To query individuals with celiac disease (CD) and non-celiac gluten sensitivity (NCGS) on their beliefs toward the health effects of gluten, and safety of vaccines and GF food products.

METHODS

We distributed a Web-based survey to individuals with CD and NCGS on a CD center e-mail list. We used univariate and multivariate analysis to compare responses of respondents with CD and NCGS.

RESULTS

The overall response rate was 27% (NCGS n = 217, CD n = 1291). Subjects with NCGS were more likely than those with CD to disagree with the statement that "vaccines are safe for people with celiac disease" (NCGS 41.3% vs. CD 26.4% (p < 0.0001), and were more likely to decline vaccination when offered (30.9 vs. 24.2%, p = 0.007). After adjusting for age and gender, NCGS subjects were more likely than CD subjects to avoid genetically modified (GMO) foods (aOR 2.30; 95% CI 1.71-3.10), eat only organic products (aOR 2.87; 95% CI 2.04-4.03), believe that the FDA is an unreliable source of information (aOR 1.82, 95% CI 1.26-2.64), and believe a GF diet improves energy and concentration (aOR 2.52; 95% CI 1.86-3.43).

CONCLUSIONS

Subjects with NCGS were more likely than those with CD to have doubts about vaccine safety and believe in the value of non-GMO and organic foods. Our findings suggest that the lack of reliable information on gluten and its content in food and medications may reinforce beliefs that result in a detriment to public health.

Characteristics and comorbidities of inpatients without celiac disease on a gluten-free diet

OBJECTIVES

Despite the increasing popularity of gluten-free diet (GFD), the demographic characteristics and medical features of patients without celiac disease on this diet have not been extensively investigated.We aimed to characterize the medical conditions and demographic backgrounds of hospitalized patients without celiac disease who adhere to a GFD, to further understand their reasons for gluten avoidance.

MATERIALS AND METHODS

We performed an observational cohort study on all inpatients at Columbia University Medical Center on a GFD in 2011-2016, excluding those with celiac disease, compared with age-matched and sex-matched inpatients on a regular diet. We determined the odds ratio (OR) of being on a GFD for various comorbidities using conditional logistic regression.

RESULTS

Of 769 inpatients on a GFD, most (63.6%) did not have celiac disease. Gluten-avoiding patients were more likely to be non-Hispanic Whites [OR: 2.92; 95% confidence interval (CI): 2.31-3.70]. They had a lower prevalence of hypertension (OR: 0.38; 95% CI: 0.27-0.52) and diabetes (OR: 0.58; 95% CI: 0.32-0.75) and higher prevalence of inflammatory bowel disease (OR: 1.56; 95% CI: 1.02-2.41), irritable bowel syndrome (OR: 6.16; 95% CI: 2.11-10.23), hyperthyroidism (OR: 2.73; 95% CI: 1.22-6.10), hypothyroidism (OR: 2.06; 95% CI: 1.39-3.06), lupus (OR: 2.87; 95% CI: 1.13-7.29), and autism spectrum disorder (OR: 23.42; 95% CI: 5.29-103.73).

CONCLUSION

Nonceliac gluten-avoiding patients have higher prevalences of inflammatory bowel disease, irritable bowel syndrome, thyroid disease, lupus, and autism spectrum disorder, suggesting patients with these disorders have turned to a GFD for perceived benefit, despite a scant evidence basis.

Fructan, Rather Than Gluten, Induces Symptoms in Patients With Self-Reported Non-Celiac Gluten Sensitivity

BACKGROUND & AIMS

Non-celiac gluten sensitivity is characterized by symptom improvement after gluten withdrawal in absence of celiac disease. The mechanisms of non-celiac gluten sensitivity are unclear, and there are no biomarkers for this disorder. Foods with gluten often contain fructans, a type of fermentable oligo-, di-, monosaccharides and polyols. We aimed to investigate the effect of gluten and fructans separately in individuals with self-reported gluten sensitivity.

METHODS

We performed a double-blind crossover challenge of 59 individuals on a self-instituted gluten-free diet, for whom celiac disease had been excluded. The study was performed at Oslo University Hospital in Norway from October 2014 through May 2016. Participants were randomly assigned to groups placed on diets containing gluten (5.7 g), fructans (2.1 g), or placebo, concealed in muesli bars, for 7 days. Following a minimum 7-day washout period (until the symptoms induced by the previous challenge were resolved), participants crossed over into a different group, until they completed all 3 challenges (gluten, fructan, and placebo). Symptoms were measured by Gastrointestinal Symptom Rating Scale Irritable Bowel Syndrome (GSRS-IBS) version. A linear mixed model for analysis was used.

RESULTS

Overall GSRS-IBS scores differed significantly during gluten, fructan, and placebo challenges; mean values were 33.1 ± 13.3, 38.6 ± 12.3, and 34.3 ± 13.9, respectively (P = .04). Mean scores for GSRS-IBS bloating were 9.3 ± 3.5, 11.6 ± 3.5, and 10.1 ± 3.7, respectively, during the gluten, fructan, and placebo challenges (P = .004). The overall GSRS-IBS score for participants consuming fructans was significantly higher than for participants consuming gluten (P = .049), as was the GSRS bloating score (P = .003). Thirteen participants had the highest overall GSRS-IBS score after consuming gluten, 24 had the highest score after consuming fructan, and 22 had the highest score after consuming placebo. There was no difference in GSRS-IBS scores between gluten and placebo groups.

CONCLUSIONS

In a randomized, double-blind, placebo-controlled crossover study of individuals with self-reported non-celiac gluten sensitivity, we found fructans to induce symptoms, measured by the GSRS-IBS. Clinicaltrials.gov no: NCT02464150.

Non-celiac gluten sensitivity: people without celiac disease avoiding gluten-is it due to histamine intolerance?

INTRODUCTION

Food intolerance/malabsorption is caused by food ingredients, carbohydrates (mainly lactose and fructose), proteins (gluten), and biogenic amines (histamine) which cause nonspecific gastrointestinal and extra-intestinal symptoms. Here we focus on possible etiologic factors of intolerance/malabsorption especially in people with non-celiac gluten sensitivity (NCGS) or the so-called people without celiac disease avoiding gluten (PWCDAG) and histamine intolerance.

METHODS

Recognizing the recently described symptoms of NCGS (PWCDAG) we review correlations and parallels to histamine intolerance (HIT).

RESULTS

We show that intestinal and extra-intestinal NCGS (PWCDAG) symptoms are very similar to those which can be found in histamine intolerance.

CONCLUSIONS

After a detailed diagnostic workup for all possible etiologic factors in every patient, a targeted dietary intervention for single or possibly combined intolerance/malabsorption might be more effective than a short-term diet low in fermentable oligo-, di- and monosaccharides and polyols (FODMAP) or the untargeted uncritical use of gluten-free diets.

Depression and insomnia among individuals with celiac disease or on a gluten-free diet in the USA: results from a national survey

BACKGROUND

There is uncertainty regarding the prevalence of psychiatric illnesses in patients with celiac disease (CD) and people who avoid gluten (PWAG) without a diagnosis of CD.

PARTICIPANTS AND METHODS

We obtained data from 22 274 participants from the 2009-2014 National Health and Nutrition Examination Survey to compare the prevalence of depression, insomnia, quality-of-life variables, and psychotropic medication use in CD participants and PWAGs to controls. We used multivariable logistic regression to assess for independent associations between CD/PWAG status and the outcomes of these variables.

RESULTS

Depression was present in 8.2% of controls compared with 3.9% of participants with CD (P=0.18) and 2.9% of PWAGs (P=0.002). After adjustment for age, sex, race, income, and access to healthcare, PWAGs maintained lower odds of depression compared with controls (odds ratio=0.25; 95% confidence interval: 0.12-0.51; P=0.0001). The prevalence estimates of sleep difficulty among controls (27.3%) compared to participants with CD or PWAGs were 37.7% (P=0.15) and 34.1% (P=0.11). Those with diagnosed CD had increased odds of sleep difficulty (odds ratio=2.41; 95% confidence interval 1.04-5.60), but this was no longer significant after multivariable adjustment (P=0.17).

CONCLUSION

Among a nationally representative US sample, participants with CD overall showed no increased odds of depression or sleep difficulty. PWAGs showed lower odds of depression compared with controls. Future research should investigate the relationship between a diagnosis of CD and the development of psychiatric conditions.

Non-coeliac gluten sensitivity

Irritable bowel syndrome-like symptoms in response to wheat ingestion is common and well described, but whether the reaction is due to gluten (i.e., non-coeliac gluten sensitivity), other wheat proteins, or FODMAPs (mostly fructans) alone or in combinations has not been clearly defined. Exclusion of coeliac disease in the presence of negative serology, and normal villous architecture but increased density of intraepithelial lymphocytes on duodenal biopsies, is difficult. Furthermore, the confidence by which a positive diagnosis is made or non-coeliac gluten sensitivity is excluded by blinded placebo-controlled rechallenge with wheat protein is reduced by strong nocebo responses generally found in patients with self-reported non-coeliac gluten sensitivity. The absence of a clear biological mechanism of action and difficulties with the design and interpretation of research studies have plunged this entity into even deeper controversy. In the absence of clarity in its diagnosis, the epidemiology, prognosis, and therapeutic approaches to a patient who may be gluten sensitive remain to be determined. Adequate understanding of the issues surrounding the controversy and further research will slowly unravel the truth behind the problem.

Self-Reported Food Hypersensitivity: Prevalence, Characteristics, and Comorbidities in the Norwegian Women and Cancer Study

BACKGROUND

This study aims to investigate the prevalence of self-reported food hypersensitivity, (SFH), the characteristics of women with SFH, and whether SFH is associated with multiple health complaints among the participants of the Norwegian Women and Cancer study (NOWAC).

METHODS

We conducted a cross-sectional study among 64,316 women aged 41-76 years. The women were randomly selected from the Norwegian Central Person Register. Information on SFH and all covariates except age and place of residence was collected by questionnaires in 2002-2005.

RESULTS

The prevalence of SFH in our study sample was 6.8% (95% confidence interval: 6.7-7.0). Logistic regression analysis showed a negative association between SFH and age (odds ratio [OR] 0.97). The odds of SFH increased among women living in or near urban centers, women with more than 9 years of education, women who did not have full-time work, women who had experienced poor economic conditions in childhood, those living without a partner, and those who did not consume alcohol or smoke (OR varied from 1.10 to 1.70). Women with a low body mass index had higher odds of SFH (OR 1.37) than those with a moderate body mass index. SFH was positively associated with poor self-perceived health (OR 2.56). The odds of SFH increased with the number of concurrent health complaints, with an OR for 5-6 comorbidities of 4.93.

CONCLUSION

We found an association between SFH, poor health, and different socio demographic and lifestyle characteristics. Women with SFH had increased odds of reporting multiple health complaints.

Less Hidden Celiac Disease But Increased Gluten Avoidance Without a Diagnosis in the United States: Findings From the National Health and Nutrition Examination Surveys From 2009 to 2014

OBJECTIVE

To investigate the trends in the prevalence of diagnosed celiac disease (CD), undiagnosed CD, and people without celiac disease avoiding gluten (PWAG) in the civilian noninstitutionalized US population from 2009 to 2014.

PATIENTS AND METHODS

We studied the occurrence of CD and PWAG in the 2009 to 2014 National Health and Nutrition Examination Surveys. The serum of all participants aged 6 years or older from the National Health and Nutrition Examination Surveys from 2009 to 2014 was tested for CD serology at Mayo Clinic. Participants were interviewed for a diagnosis of CD and the use of a gluten-free diet (GFD). The design effects of the survey and sample weights were incorporated in all statistical analyses.

RESULTS

In the US general population, the prevalence of CD did not change significantly from 0.7% (95% CI, 0.6%-0.8%) in 2009 to 2010 to 0.8% (95% CI, 0.4%-1.2%) in 2011 to 2012 to 0.7% (95% CI, 0.3%-1.0%) in 2013 to 2014. However, the prevalence of undiagnosed CD decreased from 0.6% in 2009 to 2010 to 0.3% in 2013 to 2014. In contrast, the prevalence of PWAG increased significantly from 0.5% (95% CI, 0.2%-0.9%) in 2009 to 2010 to 1.0% (95% CI, 0.6%-1.4%) in 2011 to 2012 to 1.7% (95% CI, 1.1%-2.4%) in 2013 to 2014 (P=.005 for trend).

CONCLUSION

Although the overall prevalence of CD remained stable from 2009 to 2014, the proportion of individuals with CD that is hidden considerably decreased. Moreover, the proportion of individuals without CD but following a GFD increased markedly from 2009 to 2014. Long-term health consequences of a GFD warrant further investigation.

Nonceliac Gluten Sensitivity

Nonceliac gluten sensitivity (NCGS) refers to a clinical phenotype in which patients experience intestinal and extraintestinal symptoms related to ingesting a gluten-containing diet after a diagnosis of celiac disease (CD) or wheat allergy has been excluded. CD, an autoimmune disease characterized by villous atrophy triggered by the ingestion of gluten, has increased in prevalence in recent decades, although the majority of patients remain undiagnosed. There is now an increasing public awareness of NCGS and growing interest in the health effects of gluten among health professionals and the lay public. Several randomized controlled trials have explored NCGS but have left many questions unanswered surrounding the pathophysiology, biomarkers, and established diagnostic approach to patients with this condition. Future studies are necessary to establish biomarkers and to elucidate the pathophysiology of this condition because at present, NCGS likely comprises a heterogeneous patient population. In this review, we outline the clinical trials of NCGS as well as the approach to patients with possible NCGS as recommended by an international expert panel. Because maintaining a gluten-free diet has important health, social, and economic consequences, it is necessary for medical professionals to provide practical and evidence-based advice to patients with this condition.

From coeliac disease to noncoeliac gluten sensitivity; should everyone be gluten free?

PURPOSE OF REVIEW

Gluten-free diets (GFDs) have seen a disproportional rise in use and popularity relative to the prevalence of established gluten-related disorders such as coeliac disease or immunoglobulin E wheat allergy. This entity has been termed noncoeliac gluten sensitivity (NCGS). This review aims to provide a current perspective on the emerging evidence for and against NCGS, along with the associated need for a GFD.

RECENT FINDINGS

NCGS and the benefits of a GFD are reported amongst patients with irritable bowel syndrome, inflammatory bowel disease, and nonintestinal disorders such as neuropsychiatric diseases and fibromyalgia. However, no reliable biomarkers currently exist to diagnose NCGS and hence confirmatory testing can only be performed using double-blind placebo-controlled gluten-based challenges. Unfortunately, such tests are not available in routine clinical practice. Furthermore, recent novel studies have highlighted the role of other gluten-based components in contributing to the symptoms of self-reported NCGS. These include fermentable oligo, di, mono-saccharides and polyols, amylase trypsin inhibitors, and wheat germ agglutinins. Therefore, NCGS is now seen as a spectrum encompassing several biological responses and terms such as 'noncoeliac wheat sensitivity' have been suggested as a wider label to define the condition.

SUMMARY

Despite the rising use of a GFD further studies are required to clearly establish the extent and exclusivity of gluten in NCGS.

Celiac disease and non-celiac gluten sensitivity

Celiac disease is a multisystem immune based disorder that is triggered by the ingestion of gluten in genetically susceptible individuals. The prevalence of celiac disease has risen in recent decades and is currently about 1% in most Western populations. The reason for this rise is unknown, although environmental factors related to the hygiene hypothesis are suspected. The pathophysiology of celiac disease involves both the innate and adaptive immune response to dietary gluten. Clinical features are diverse and include gastrointestinal symptoms, metabolic bone disease, infertility, and many other manifestations. Although a gluten-free diet is effective in most patients, this diet can be burdensome and can limit quality of life; consequently, non-dietary therapies are at various stages of development. This review also covers non-celiac gluten sensitivity. The pathophysiology of this clinical phenotype is poorly understood, but it is a cause of increasing interest in gluten-free diets in the general population.

Practical insights into gluten-free diets

Coeliac disease is a global disease, and the only currently available treatment is a gluten-free diet (GFD). Although conceptually simple, the diet changes are substantial and have a profound effect on a patient's life. Untreated coeliac disease is associated with complications, including excess mortality, most of which can be avoided with a strict GFD. However, there are many barriers, including availability, cost and safety of gluten-free foods, and gluten cross-contamination. The GFD can be restrictive in social situations, leading to poor quality of life and, ultimately, nonadherence. As the number of patients with coeliac disease increases worldwide, clinicians need to be aware of the challenges patients face. Heightened awareness by physicians, dietitians and other providers can help maximize successful treatment, improve outcomes, and reduce health-care costs and disease burden. Routine follow-up is necessary to reinforce the need for a GFD, provide social and emotional support, and achieve mucosal healing, leading to reduced risk of complications. Unfortunately, there is wide variation in follow-up practices. The objective of this Review is to increase awareness of the challenges, management and follow-up of patients with coeliac disease to help them achieve GFD adherence and prevent complications whilst preserving their quality of life.

Noncoeliac gluten sensitivity: a diagnostic dilemma

PURPOSE OF REVIEW

Noncoeliac gluten sensitivity (NCGS) has gained attention as an emerging clinical entity. Data regarding the epidemiology, pathogenesis, and management of NCGS are scattered in view of the diagnostic uncertainty surrounding the disorder. We aim to provide a current perspective of NCGS and its associated controversies.

RECENT FINDINGS

NCGS consists of a spectrum of intestinal and extraintestinal symptoms related to the ingestion of gluten-containing food, yet in the absence of coeliac disease or wheat allergy. To date, no specific biomarker exists for NCGS, thereby leaving the diagnosis to be confirmed by dietary elimination followed by double-blind placebo-controlled gluten-based rechallenges. Unfortunately, this technique is cumbersome, not readily-available in routine clinical practise, and can still leave the diagnosis of NCGS open to debate as to whether the effects demonstrated can be specifically attributed to the gluten-protein per se or rather coexisting nongluten components, such as fermentable carbohydrates and amylase-trypsin inhibitors.

SUMMARY

Physicians are increasingly being posed with the dilemma of patients presenting with self-reported NCGS. However, this appears to be the tip of the iceberg and future studies are in need of delineating which gluten-based component is responsible for each individual patient's complaint.

The spectrum of noncoeliac gluten sensitivity

The past 5 years have seen an increase in the use of a gluten-free diet outside a diagnosis of coeliac disease or IgE-mediated wheat allergy. This trend has led to the identification of a new clinical entity termed noncoeliac gluten sensitivity (NCGS). In this Review, we discuss the evidence for NCGS as demonstrated by the results of double-blind, placebo-controlled dietary rechallenge studies. Furthermore, the characteristic phenotype of individuals with NCGS is described as well as the symptom manifestations commonly reported after gluten exposure, which include intestinal symptoms consistent with IBS, and extraintestinal symptoms such as neurological dysfunction, psychological disturbances, fibromyalgia and skin rash. Moreover, emerging evidence suggests that NCGS can be associated with organic gastrointestinal pathologies, such as IBD, in which its presence might be a reflection of severe or stricturing disease. However, NCGS is not without its controversies and uncertainties, in particular pertaining to whether it is gluten or nongluten components of the grain evoking symptoms; evidence suggests that fermentable carbohydrates, amylase trypsin inhibitors and wheat-germ agglutinin can also be responsible culprits. Finally, we discuss the novel techniques that might help diagnose NCGS in the future.

Nonceliac Gluten Sensitivity

Nonceliac gluten sensitivity (NCGS) is the clinical term used to describe gastrointestinal (GI) and/or extraintestinal symptoms associated with gluten ingestion. The prevalence of NCGS is unknown. The condition has clinical features that overlap with those of celiac disease (CD) and wheat allergy (WA). The pathophysiologic process in NCGS is thought to be through an innate immune mechanism, whereas CD and WA are autoimmune- and allergen-mediated, respectively. However, dietary triggers other than gluten, such as the fermentable oligosaccharides, disaccharides, monosaccharides, and polyols, have been implicated. Currently, no clinical biomarker is available to diagnose NCGS. Exclusion of CD and WA is necessary in the evaluation of a patient suspected to have NCGS. The onset of symptoms in patients with NCGS can occur within hours or days of gluten ingestion. Patients with NCGS have GI and extraintestinal symptoms that typically disappear when gluten-containing grains are eliminated from their diets. However, most patients suspected to have NCGS have already initiated a gluten-free diet at the time of an evaluation. A gluten elimination diet followed by a monitored open challenge of gluten intake to document recurrence of GI and/or extraintestinal symptoms can sometimes be helpful. If NCGS is strongly suggested, then a skilled dietitian with experience in counseling on gluten-free diets can provide proper patient education. Additional research studies are warranted to further our understanding of NCGS, including its pathogenesis and epidemiology, and to identify a biomarker to facilitate diagnosis and patient selection for proper management.

Cost Effectiveness of Routine Duodenal Biopsy Analysis for Celiac Disease During Endoscopy for Gastroesophageal Reflux

BACKGROUND & AIMS

Some patients with refractory gastroesophageal reflux disease (GERD) actually have undiagnosed celiac disease. These patients often undergo an esophagogastroduodenoscopy (EGD) to determine the etiology and severity of GERD. Performing routine duodenal biopsy analysis during an EGD could identify patients with celiac disease. We evaluated the cost effectiveness of this approach.

METHODS

We performed a systematic search of the MEDLINE database to identify publications through March 2014 on patients who underwent a duodenal biopsy analysis during an EGD for GERD. Data collected were used to construct a decision tree to calculate the cost effectiveness of an EGD with and without celiac disease tests.

RESULTS

Among 10,000 patients with refractory GERD who underwent an EGD, we predicted a biopsy strategy would detect 70% of patients with celiac disease if the prevalence of celiac disease was 1% in this cohort. Biopsy analysis at the start of the EGD procedure would increase the remaining quality-adjusted life years (QALYs) by 0.0032, and increase the lifetime cost by $389/patient. Compared with no biopsy, the biopsy strategy cost $55,692.86/case of celiac disease detected, and $121,875/QALY gained. The incremental cost-effectiveness ratio for the biopsy strategy met the threshold of less than $50,000/QALY when 1 of the following parameters was met: when the utility of living with GERD was less than 0.88, when the prevalence of celiac disease in patients with refractory GERD was greater than 1.8%, when biopsy analysis detected celiac disease with more than 98.1% specificity, when the cost of a gluten-free diet was less than $645.85/y, or if the cost of proton pump inhibitor therapy was more than $5874.01/y.

CONCLUSIONS

Based on base-case values, it is not cost effective to perform a biopsy analysis to detect celiac disease in patients undergoing an EGD for refractory GERD. However, the approach becomes cost effective when the prevalence of celiac disease in this population is 1.8% or greater.

Celiac disease

This review will focus on the pathogenesis, clinical manifestations, diagnosis, and management of celiac disease (CD). Given an increasing awareness of gluten-related disorders, medical professionals of all varieties are encountering patients with a diagnosis of CD or who are thought to have food intolerance to gluten. The prevalence of CD among the general population is estimated to be 1% in Western nations, and there is growing evidence for underdiagnosis of the disease, especially in non-Western nations that were traditionally believed to be unaffected. The development of serologic markers specific to CD has revolutionized the ability both to diagnose and monitor patients with the disease. Additionally, understanding of the clinical presentations of CD has undergone a major shift over the past half century. Although it is well understood that CD develops in genetically predisposed subjects exposed to gluten, the extent of other environmental factors in the pathogenesis of the disease is an area of continued research. Currently, the main therapeutic intervention for CD is a gluten-free diet; however, novel nondietary agents are under active investigation. Future areas of research should also help us understand the relationship of CD to other gluten-related disorders.

Non-celiac gluten sensitivity: a work-in-progress entity in the spectrum of wheat-related disorders

Non-celiac gluten sensitivity is an undefined syndrome with gastrointestinal and extra-intestinal manifestations triggered by gluten in patients without celiac disease and wheat allergy. The pathogenesis involves immune-mediated mechanisms requiring further research. Symptoms disappear in a few hours or days after gluten withdrawal and recur rapidly after gluten ingestion. Besides gluten, other wheat proteins as well as fermentable oligo-, di-, mono-saccharides and polyols (FODMAPs) may contribute to this syndrome. This syndrome occurs mainly in young women, being rare in children. Its prevalence ranges from 0.6% to 6%, based on primary or tertiary care center estimates. No biomarker is available, but half of patients tests positive for IgG anti-gliadin antibodies, which disappear quickly after gluten-free diet together with symptoms. Also, genetic markers are still undefined. Although currently limited to a research setting, double-blind, placebo-controlled, cross-over trial strategy is recommended to confirm the diagnosis. Treatment is based on dietary restriction with special care to nutrient intake.

Systematic review: noncoeliac gluten sensitivity

BACKGROUND

Noncoeliac gluten sensitivity (NCGS) is a controversial emerging disorder. Despite reported symptoms related to the ingestion of gluten, NCGS remains a diagnosis based on the exclusion of coeliac disease, given the absence of reliable biomarkers.

AIM

To evaluate the prevalence, diagnostic exclusion of coeliac disease and the efficacy of a gluten-free diet (GFD) for NCGS patients.

METHODS

A PubMed search was performed up to December 2014. According to consensus diagnostic criteria, NCGS was defined as self-reported gluten intolerance, negative coeliac serology and absence of villous atrophy. Studies evaluating the impact of a GFD on patients with irritable bowel syndrome (IBS) were also included.

RESULTS

Prevalence rates of NCGS (0.5-13%) differed widely. Seventeen studies, including 1561 patients (26 children), met the inclusion criteria for NCGS. HLA haplotypes could not be linked to histology [normal or lymphocytic enteritis (LE)] in 1123 NCGS patients. HLADQ2/DQ8 haplotypes were present in 44% of NCGS patients. After advanced diagnostic techniques in 189 NCGS patients combining LE and HLADQ2/DQ8 haplotypes, 39 (20%) were reclassified as coeliac disease. There was a higher than expected family history of coeliac disease and autoimmune disorders in NCGS patients. A GFD resulted in variable results for variable, but significantly improved stool frequency in HLADQ2 positive diarrhoea-predominant IBS patients.

CONCLUSIONS

Prevalence rates for NCGS are extremely variable. A subset of NCGS patients might belong in the so-called 'coeliac-lite' disease. The benefit of a GFD for NCGS patients is currently controversial. HLADQ2 positive diarrhoea-type IBS patients might gain symptom improvement from a GFD.

A study evaluating the bidirectional relationship between inflammatory bowel disease and self-reported non-celiac gluten sensitivity

BACKGROUND

Non-celiac gluten sensitivity and the associated use of a gluten-free diet (GFD) are perceived to belong to the spectrum of irritable bowel syndrome (IBS). However, recent reports suggest substantial use of a GFD in inflammatory bowel disease (IBD). We assessed the bidirectional relationship between IBD and self-reported non-celiac gluten sensitivity (SR-NCGS).

METHODS

A cross-sectional questionnaire screened for SR-NCGS and the use of a GFD in 4 groups: ulcerative colitis (n = 75), Crohn's disease (n = 70), IBS (n = 59), and dyspeptic controls (n = 109). We also assessed diagnostic outcomes for IBD in 200 patients presenting with SR-NCGS.

RESULTS

The prevalence of SR-NCGS was 42.4% (n = 25/59) for IBS, followed by 27.6% (n = 40/145) for IBD, and least among dyspeptic controls at 17.4% (n = 19/109); P = 0.015. The current use of a GFD was 11.9% (n = 7/59) for IBS, 6.2% (n = 9/145) for IBD, and 0.9% (1/109) for dyspeptic controls; P = 0.02. No differences were established between ulcerative colitis and Crohn's disease. However, Crohn's disease patients with SR-NCGS were significantly more likely to have stricturing disease (40.9% versus 18.9%, P = 0.046), and higher mean Crohn's Disease Activity Index score (228.1 versus 133.3, P = 0.002), than those without SR-NCGS. Analysis of 200 cases presenting with SR-NCGS suggested that 98.5% (n = 197) could be dietary-related IBS. However, 1.5% (n = 3) were found to have IBD; such patients had associated alarm symptoms, and/or abnormal blood parameters, prompting colonic investigations.

CONCLUSIONS

SR-NCGS is not only exclusive to IBS but also associated with IBD, where its presence may be reflecting severe or stricturing disease. Randomized studies are required to further delineate the nature of this relationship and clarify whether a GFD is a valuable dietetic intervention in selected IBD patients.

Risk of low bone mineral density and low body mass index in patients with non-celiac wheat-sensitivity: a prospective observation study

BACKGROUND

Non-celiac gluten sensitivity (NCGS) or 'wheat sensitivity' (NCWS) is included in the spectrum of gluten-related disorders. No data are available on the prevalence of low bone mass density (BMD) in NCWS. Our study aims to evaluate the prevalence of low BMD in NCWS patients and search for correlations with other clinical characteristics.

METHODS

This prospective observation study included 75 NCWS patients (63 women; median age 36 years) with irritable bowel syndrome (IBS)-like symptoms, 65 IBS and 50 celiac controls. Patients were recruited at two Internal Medicine Departments. Elimination diet and double-blind placebo controlled (DBPC) wheat challenge proved the NCWS diagnosis. All subjects underwent BMD assessment by Dual Energy X-Ray Absorptiometry (DXA), duodenal histology, HLA DQ typing, body mass index (BMI) evaluation and assessment for daily calcium intake.

RESULTS

DBPC cow's milk proteins challenge showed that 30 of the 75 NCWS patients suffered from multiple food sensitivity. Osteopenia and osteoporosis frequency increased from IBS to NCWS and to celiac disease (CD) (P <0.0001). Thirty-five NCWS patients (46.6%) showed osteopenia or osteoporosis. Low BMD was related to low BMI and multiple food sensitivity. Values of daily dietary calcium intake in NCWS patients were significantly lower than in IBS controls.

CONCLUSIONS

An elevated frequency of bone mass loss in NCWS patients was found; this was related to low BMI and was more frequent in patients with NCWS associated with other food sensitivity. A low daily intake of dietary calcium was observed in patients with NCWS.

Predictors of dietary gluten avoidance in adults without a prior diagnosis of celiac disease

OBJECTIVE

Prior studies have shown that dietary gluten avoidance (DGA) is relatively common in children without previously diagnosed celiac disease (CD), and several clinical predictors of DGA have been found. However, available data on predictors of DGA in adults without diagnosed CD are limited. The aim of this study was to determine the independent predictors of DGA in this population.

METHODS

We performed a structured medical record review of 376 patients, ages ≥ 20 y, who had never been formally diagnosed with CD, presenting for an initial CD evaluation (ICD-9-CM 579.0) between January 2000 and December 2010 at two large Boston teaching hospitals. We collected data including demographic characteristics, medical history, history of CD serology before referral, and self-reported DGA. Predictors of DGA were determined using multivariable logistic regression.

RESULTS

Mean age was 47 (SD = 17) years. We found that 41 patients (10.9%; 95% confidence interval [CI], 7.9-14.5) had avoided gluten at some time in their lives. Most patients had subjective abdominal complaints or bowel movement changes. History of CD seropositivity before referral was noted in 14%. Independent predictors of DGA (P < 0.05) were lactose intolerance (odds ratio [OR], 2.8; 95% CI, 1.1-7.5), food allergy (OR, 3.8; 95% CI, 1.04-13.7), and history of positive serology of less-specific CD markers before the referral (OR, 3.2; 95% CI, 1.3-7.9).

CONCLUSIONS

Gluten avoidance is common in a clinic population of adults without prior CD diagnosis. The recognized predictors suggest that DGA may associate with conditions presenting with nonspecific gastrointestinal complaints and perhaps with the perceived benefits of DGA among patients with prior history of positive CD serology.

An Italian prospective multicenter survey on patients suspected of having non-celiac gluten sensitivity

BACKGROUND

Non-celiac gluten sensitivity (NCGS) is still an undefined syndrome with several unsettled issues despite the increasing awareness of its existence. We carried out a prospective survey on NCGS in Italian centers for the diagnosis of gluten-related disorders, with the aim of defining the clinical picture of this new syndrome and to establish roughly its prevalence compared with celiac disease.

METHODS

From November 2012 to October 2013, 38 Italian centers (27 adult gastroenterology, 5 internal medicine, 4 pediatrics, and 2 allergy) participated in this prospective survey. A questionnaire was used in order to allow uniform and accurate collection of clinical, biochemical, and instrumental data.

RESULTS

In total, 486 patients with suspected NCGS were identified in this 1-year period. The female/male ratio was 5.4 to 1, and the mean age was 38 years (range 3-81). The clinical picture was characterized by combined gastrointestinal (abdominal pain, bloating, diarrhea and/or constipation, nausea, epigastric pain, gastroesophageal reflux, aphthous stomatitis) and systemic manifestations (tiredness, headache, fibromyalgia-like joint/muscle pain, leg or arm numbness, 'foggy mind,' dermatitis or skin rash, depression, anxiety, and anemia). In the large majority of patients, the time lapse between gluten ingestion and the appearance of symptoms varied from a few hours to 1 day. The most frequent associated disorders were irritable bowel syndrome (47%), food intolerance (35%) and IgE-mediated allergy (22%). An associated autoimmune disease was detected in 14% of cases. Regarding family history, 18% of our patients had a relative with celiac disease, but no correlation was found between NCGS and positivity for HLA-DQ2/-DQ8. IgG anti-gliadin antibodies were detected in 25% of the patients tested. Only a proportion of patients underwent duodenal biopsy; for those that did, the biopsies showed normal intestinal mucosa (69%) or mild increase in intraepithelial lymphocytes (31%). The ratio between suspected NCGS and new CD diagnoses, assessed in 28 of the participating centers, was 1.15 to 1.

CONCLUSIONS

This prospective survey shows that NCGS has a strong correlation with female gender and adult age. Based on our results, the prevalence of NCGS seems to be only slightly higher than that of celiac disease.