Exploring the associations between lifestyle and dietary patterns with preclinical alzheimer's disease: findings from...

Modifiable lifestyle factors play an important role in maintaining brain health. This study aimed to investigate lifestyle behaviours, with a special focus on dietary patterns, associated with preclinical Alzheimer's disease, and to evaluate the urinary diet-polyphenol metabolites as objective biomarkers of plant-based food consumption by integration of the targeted metabolomics with self-reported dietary assessments.

We conducted a case-control study including 50 individuals diagnosed with preclinical Alzheimer's disease and 48 cognitively healthy controls (aged 55-75 years, both sexes). Demographic characteristics, cardiovascular risk factors, physical activity, cognitive and social engagement, and dietary patterns were assessed. The 24-hour urine samples were analysed by targeted ultra-high-performance liquid chromatography coupled to triple quadrupole tandem mass spectrometry (UHPLC-QqQ-MS/MS).

Dietary patterns characterised by higher daily consumption of vegetables and nuts and lower of processed foods, consistent with the MIND diet score, were associated with better cognitive outcomes. These associations were strengthened by engagement in cognitively stimulating activities. Urinary polyphenol metabolites, including anthocyanins, stilbenes, and gut microbiota-derived metabolites of dietary flavan-3-ols such as valerolactones and phenolic acids, were positively associated with the consumption of plant-based foods.

Lifestyle modifications combining plant-rich dietary patterns with cognitive stimulation may support cognitive resilience in individuals with preclinical Alzheimer's disease diagnosis. Urinary polyphenol metabolites represent objective biomarkers that can enhance the accuracy of diet-brain health assessments.