Cognitive impairment in coeliac disease improves on a gluten-free diet and correlates with histological and serological indices of disease severity.

Alimentary pharmacology & therapeutics. 2014;40(2):160-70

Plain language summary

Coeliac disease (CD) is an inflammatory autoimmune disorder caused by the ingestion of gluten. While CD is known to primarily affect the bowel, there is reported evidence of potential neurological side effects. Cognition may be impaired in undiagnosed CD patients because of nutrient deficiencies, systemic inflammation and changes in the gut microbiome. CD patients often report a mild cognitive impairment, brain fog, characterised by difficulty concentrating, short-term memory and confusion. The aim of this study was to investigate the relationship between gut mucosal healing and cognitive function in eleven patients recently diagnosed with CD commencing a strict gluten-free diet. The findings of this study showed that in newly diagnosed CD patients, cognitive functioning improved with a gluten-free diet and was correlated with mucosal healing. Based on this study, the authors conclude that cognition is impaired in people with untreated coeliac disease and may affect the performance of everyday tasks. This finding also introduces the possibility of using cognitive tests to provide a marker of intestinal healing.

Abstract

BACKGROUND Mild impairments of cognition or 'Brain fog' are often reported by patients with coeliac disease but the nature of these impairments has not been systematically investigated. AIM: This longitudinal pilot study investigated relationships between cognitive function and mucosal healing in people with newly diagnosed coeliac disease commencing a gluten-free diet. METHODS Eleven patients (8 females, 3 males), mean age 30 (range 22-39) years, were tested with a battery of cognitive tests at weeks 0, 12 and 52. Information processing efficacy, memory, visuospatial ability, motoric function and attention were tested. Small bowel biopsies were collected via routine gastroscopy at weeks 12 and 52 and were compared to baseline Marsh scores. Cognitive performance was compared to serum concentrations of tissue transglutaminase antibodies, biopsy outcomes and other biological markers. RESULTS All patients had excellent adherence to the diet. Marsh scores improved significantly (P = 0.001, Friedman's test) and tissue transglutaminase antibody concentrations decreased from a mean of 58.4 at baseline to 16.8 U/mL at week 52 (P = 0.025). Four of the cognitive tests assessing verbal fluency, attention and motoric function showed significant improvement over the 12 months and strongly correlated with the Marsh scores and tissue transglutaminase antibody levels (r = 0.377-0.735; all P < 0.05). However, no meaningful patterns of correlations were found for nutritional or biochemical markers, or markers of intestinal permeability. CONCLUSIONS In newly diagnosed coeliac disease, cognitive performance improves with adherence to the gluten-free diet in parallel to mucosal healing. Suboptimal levels of cognition in untreated coeliac disease may affect the performance of everyday tasks.

Lifestyle medicine

Fundamental Clinical Imbalances : Neurological ; Digestive, absorptive and microbiological
Patient Centred Factors : Mediators/Gluten
Environmental Inputs : Diet
Personal Lifestyle Factors : Nutrition
Functional Laboratory Testing : Tissue biopsy

Methodological quality

Allocation concealment : Not applicable

Metadata