Introduction

Non-coeliac gluten/wheat sensitivity (NCGWS) is characterized by gastrointestinal and extra-intestinal symptoms triggered by gluten/wheat ingestion in patients without coeliac disease (CD) or wheat allergy. There are controversies on the mechanism leading to this phenomenon, including media influence and the presence of a nocebo effect. Moreover, after the COVID-19 pandemic, a decrease in the rates of NCGWS diagnosis has been noted. The only treatment available for the management of NCGWS is a gluten/wheat-free diet (GFD), yet long-term outcomes are poorly understood. This study aimed to evaluate post-pandemic trends in NCGWS and the long-term GFD adherence in patients with NCGWS. The secondary goals are the assessment of the perceived efficacy of GFD and the need of further medical support.

Aims & Methods

We retrieved data from gluten-free products vendors up to September 2024 (top 6 retailer in the UK) and gluten free products customers up to July 2021, using a questionnaire. Subsequently, patients with self-reported NCGWS referred to a tertiary center clinic from 2006 to 2018 completed a questionnaire regarding their dietary habits and further need of medical advice for symptoms related to their diagnosis. The Biagi score was used to assess their adherence to a GFD. We compared the dietary adherence scores to age and sex matched controls cohort of patients with CD to validate the results.

Results

The marked data analysis showed a persistent rise in the sales of gluten free products, from £200B in 2014 vs £600B in 2024. Moreover, NCGWS patients account for 9.7% of the total number of buyers and for 26% of the spent for GF products.
In our cohort, out of 186 patients with NCGWS, 111 answered the questionnaire (response rate 59.7%, female 82.0%, average age 54 ± 13 years). Of these 111, 58 are not currently following a GFD. Out of the 53/111 patients following a GFD, only 27/53 (50,9%) are adhering strictly (Biagi score 3-4), 2/53 had a Biagi score of 2 (3,8%) indicating poor adherence to a gluten free diet, and 24/53 (45,2%) voluntarily ate gluten (Biagi 1-0). Only two patients report that gluten/wheat is not causing them any symptoms if eaten. The average time patients remained on a gluten free diet was 141±58 months. Compared to patients with CD those with NCGWS on a GFD showed a significantly lower adherence to a GFD (Biagi score of 0-1 NCGS: 73.9% vs CD: 8.1%, p<0.05; Biagi score 3-4, NCGWS: 24.3% vs CD: 90.1%, p<0.05). After being discharged, 40 patients (36.0%) sought medical advice again, but no significant correlation was found between the adherence to a GFD and need for further medical intervention.

Conclusion

Self-reported NCGWS is still consistently present among general population. Unlike CD, the vast majority of patients with self-reported NCGWS do not continue a GFD or significantly reduce their level of adherence. Still, NCGWS patients account for a vast part of the expenses in the gluten-free market. However, over a third of NCGWS sought further medical advice to manage their symptoms. These findings underline the need of a better understanding of this condition and the challenges in the management of these patients.

References

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