Systematic review and meta-analysis of the action of gut microbiota and nutrology in celiac disease: state of the art

Introduction: Celiac disease (CD) is one of the most common disorders related to diet, with a global prevalence of about 1%. The aggravations caused by CD promote an imbalance in the gut microbiota (GM). However, it is not yet known specifically how the gut microbiota plays a role in the pathogeny of this disease, and whether microbiota dysbiosis would be the cause or consequence of CD. Objective: The present study aimed to correlate the main results of the action of the gut microbiota and functional nutrition for the treatment of celiac disease. Methods: This study followed the rules of PRISMA. The research was carried out from June 2021 to 2022 and developed at Scopus, PubMed/Medline, Science Direct, Google Scholar, and Ovid. The quality of the evidence was classified according to the GRADE. The Cochrane instrument was adopted to assess the risk of bias of included studies. For data analysis, Minitab 18® statistical program was used. A common descriptive statistical analysis was performed. The One-Way test (ANOVA) was applied, adopting the α level lower than 0.05 with a statistically significant difference for the 95% CI. Results: The present study found thirteen (13) important clinical studies, of which 12 were Randomized Controlled Studies (RCTs) and one (1) Cross-Sectional Observational study of the total of 113 studies evaluated, showing a high quality of scientific evidence in the studies addressed, with a level of scientific evidence AI. Also, the analyzed studies showed high homogeneity in the results (high association=>50%) to studies with larger sample sizes (greater precision), presenting 98.65%. The present study showed that certain diets/probiotics can promote the improvement of GM as well as DC, especially in patients on a gluten-free diet (GFD). Therefore, patients who follow a GFD may be prone to nutritional deficiencies. Conclusion: According to the results, although some studies have a small sample size, the main randomized clinical studies showed that the modulation of nutrients/probiotics and the gut microbiota improve the inflammatory process of celiac disease, especially in patients with a gluten-free diet.