Mediterranean diet adherence and cognitive function in older, UK adults: The EPIC-Norfolk study

Background In Mediterranean countries, adherence to a traditional Mediterranean dietary pattern (MedDiet) is associated with better cognitive function and reduced dementia risk. It is unclear if similar benefits exist in non-Mediterranean regions. Objective To examine associations between MedDiet adherence and cognitive function in an older, UK population. To investigate whether associations differed between individuals with high versus low cardiovascular disease (CVD) risk. Design We conducted an analysis in 8009 older individuals with dietary data at Health Check 1 (1993-1997) and cognitive function data at Health Check 3 (2006-2011) of the European Prospective Investigation of Cancer, Norfolk (EPIC-Norfolk). Associations were explored between MedDiet adherence and global and domain specific cognitive test scores and risk of poor cognitive performance in the entire cohort, and when stratified according to CVD risk status. Results Higher MedDiet adherence defined by the Pyramid MedDiet score was associated with better global cognition (β±SE=-0.012±0.002; P<0.001), verbal episodic memory (β±SE=-0.009±0.002; P<0.001), and simple processing speed (β±SE=-0.002±0.001; P=0.013). Lower risk of poor verbal episodic memory (OR(95%CI)=0.784 (0.641,0.959); P=0.018), complex processing speed (OR(95%CI)=0.739 (0.601,0.907); P=0.004), and prospective memory (OR(95%CI)=0.841 (0.724,0.977); P=0.023) was also observed for the highest versus lowest Pyramid MedDiet tertiles. The effect of a one-point increase in Pyramid score on global cognitive function was equivalent to 1.7 fewer years of cognitive ageing. MedDiet adherence defined by the MEDAS score (mapped using both binary and continuous scoring) showed similar, albeit less consistent, associations. In stratified analyses, associations were evident in individuals at higher CVD risk only (P<0.05). Conclusions Higher adherence to the MedDiet is associated with better cognitive function and lower risk of poor cognition in older, UK adults. This evidence underpins the development of interventions to enhance MedDiet adherence, particularly in individuals at higher CVD risk, aiming to reduce the risk of age-related cognitive decline in non-Mediterranean populations

Feasibility and acceptability of a multi-domain intervention to increase Mediterranean diet adherence and physical activity in older UK adults at risk of dementia: Protocol for the MedEx-UK randomised controlled trial

Introduction Dementia prevalence continues to increase, and effective interventions are needed to prevent, delay or slow its progression. Higher adherence to the Mediterranean diet (MedDiet) and increased physical activity (PA) have been proposed as strategies to facilitate healthy brain ageing and reduce dementia risk. However, to date, there have been no dementia prevention trials in the UK focussed on combined dietary and PA interventions. This study aims to: (1) assess feasibility and acceptability of a theory-underpinned digital and group-based intervention for dementia risk reduction in an 'at risk' UK cohort; (2) evaluate behaviour change responses to the intervention; and, (3) provide information on cognitive, neurological, vascular and physiological outcomes to inform the design of a follow-on, full-scale efficacy trial. Methods One hundred and eight participants aged 55 to 74 years with a QRISK2 score of ≥10% will be recruited to take part in this 24-week multi-site study. Participants will be randomised into three parallel arms: (1) Control; (2) MedDiet; and, (3) MedDiet+PA. The study will evaluate a personalised website, group session and food delivery intervention to increase MedDiet adherence and PA in older adults at risk of dementia. Diet and PA will be monitored prior to, during and following the intervention. Feasibility, acceptability and hypothesised mediators will be assessed in addition to measures of cognitive function, brain structure/perfusion (MRI), vascular function and metabolic markers (blood, urine and faecal) prior to, and following, the intervention. Discussion This trial will provide insights into the feasibility, acceptability and mechanism of effect of a multi-domain intervention focussed on the MedDiet alone and PA for dementia risk reduction in an 'at risk' UK cohort. Ethics and dissemination The study has received NHS REC and HRA approval (18/NI/0191). Findings will be disseminated via conference presentations, public lectures, and peer-reviewed publications. Trial registration details ClinicalTrials.gov NCT03673722

Amelogenesis Imperfecta; Genes, Proteins And Pathways

Amelogenesis imperfecta (AI) is the name given to a heterogeneous group of conditions characterised by inherited developmental enamel defects. AI enamel is abnormally thin, soft, fragile, pitted and/or badly discoloured, with poor function and aesthetics, causing patients problems such as early tooth loss, severe embarrassment, eating difficulties and pain. It was first described separately from diseases of dentine nearly 80 years ago, but the underlying genetic and mechanistic basis of the condition is only now coming to light. Mutations in the gene AMELX, encoding an extracellular matrix protein secreted by ameloblasts during enamel formation, were first identified as a cause of AI in 1991. Since then, mutations in at least eighteen genes have been shown to cause AI presenting in isolation of other health problems, with many more implicated in syndromic AI. Some of the encoded proteins have well documented roles in amelogenesis, acting as enamel matrix proteins or the proteases that degrade them, cell adhesion molecules or regulators of calcium homeostasis. However, for others, function is less clear and further research is needed to understand the pathways and processes essential for the development of healthy enamel. Here, we review the genes and mutations underlying AI presenting in isolation of other health problems, the proteins they encode and knowledge of their roles in amelogenesis, combining evidence from human phenotypes, inheritance patterns, mouse models and in vitro studies. An LOVD resource (http://dna2.leeds.ac.uk/LOVD/) containing all published gene mutations for AI presenting in isolation of other health problems is described. We use this resource to identify trends in the genes and mutations reported to cause AI in the 270 families for which molecular diagnoses have been reported by 23rd May 2017. Finally we discuss the potential value of the translation of AI genetics to clinical care with improved patient pathways and speculate on the possibility of novel treatments and prevention strategies for AI

GABA system dysfunction in autism and related disorders: From synapse to symptoms

Autism Spectrum Disorders (ASDs) are neurodevelopmental syndromes characterised by repetitive behaviours and restricted interests, impairments in social behavior and relations, and in language and communication. These symptoms are also observed in a number of developmental disorders of known origin, including Fragile X Syndrome, Rett syndrome, and Fetal Anticonvulsant Syndrome. While these conditions have diverse etiologies, and poorly understood pathologies, emerging evidence suggests that they may all be linked to dysfunction in particular aspects of GABAergic inhibitory signalling in the brain. We review evidence from genetics, molecular neurobiology and systems neuroscience relating to the role of GABA in these conditions. We conclude by discussing how these deficits may relate to the specific symptoms observed