Dietary patterns among 70-year-olds in relation to CSF-biomarkers for Alzheimer’s disease

Objectives: Evidence suggests that diet could be a modifiable factor in the prevention of Alzheimer´s disease (AD). High quality dietary patterns, such as the Mediterranean diet, has been suggested as protective, and lower quality dietary patterns, such as the western diet, has been suggested as a risk factor. Studies on the associations between dietary patterns and biomarker pathways for AD, are still limited. The aim of this study is to investigate the relation between dietary patterns and CSF-biomarkers of relevance for AD in a sample of 70-year-olds from the general population.

Methods: Data was derived from the population based Gothenburg H70 Birth Cohort Studies in Gothenburg, Sweden (n=1203). There were 273 non-demented participants with dietary- and CSF data (49% women).  CSF levels of β-amyloid (Aβ)42, total tau, and phosphorylated tau were measured with ELISA-based methods. Dietary intake was determined by the diet history method. Dietary intake was divided into food groups, and energy and nutrient intake were calculated. Statistical analyses were performed using general linear models, adjusted for energy intake, APOE4, BMI, education, and physical activity level

Results: Lower levels of β-amyloid in CSF were associated with a higher intake of fast food, fiber, fiber rich bread and cereals among men (p=0,041). Among women, lower levels of β-amyloid were associated with a higher intake of sweets (p=0.022), before adjusting for covariates, but not after. Higher levels of total tau and phosphorylated tau were associated with a higher margarine intake (primarily butter based) among men (p=0.048). Among women, higher tau-levels were associated with a higher intake of soda (p=0.003).

Conclusions: Preliminary results indicate that the intake of lower quality foods, such as fast food, butter based margarines and soda, was related to more pathological levels of the CSF-biomarkers. In men, we also found a relation between fibre, fibre rich bread and cereals and more pathological levels. Fibre are considered healthy, but the dietary quality of fibre rich bread and cereals can vary. Further analyses will be conducted using a Mediterranean dietary index and principal component analyses (PCA) to investigate dietary patterns associated with CSF-biomarkers of amyloid and tangle pathology and neurodegeneration.