Dietary patterns among older adults - With focus on dementia and related biomarkers

Abstract

Background and aim: Diet is a lifestyle factor that can influence healthy ageing and the risk of developing dementia. Studies investigating dietary patterns among older adults in relation to dementia, and dementia-related factors, can provide insights that will enable precision nutrition in dementia prevention strategies. The aim of this thesis was to investigate nutrient- and dietary intake among older adults, to explore associations between dietary patterns and dementia-related biomarkers, and to investigate potential gene-dietary pattern interactions in relation to incident dementia. Method: Data were derived from the population-based Gothenburg H70 Birth Cohort Studies, including the Prospective Population Study of Women in Gothenburg, Sweden. There were five birth cohorts of 70-year-olds (n= 2 246) that participated in the dietary examinations between 1971 – 2016. Results: Findings from paper I showed that the intake of healthy foods and alcohol increased among 70-year-olds between 1971 – 2016, and that the proportion of 70-year-olds at risk of an inadequate nutrient intake decreased over time. In paper II, we found associations between higher adherence to a western dietary pattern and preclinical Alzheimer’s disease (pathological alterations but no apparent symptoms). In paper III, we found interactions between dietary patterns and APOE ε4 (genetic risk factor for Alzheimer’s disease) status in relation to incident dementia, where APOE ε4 carriers with a high adherence to a western dietary pattern had an increased risk of dementia, whilst APOE ε4 non-carriers with a high adherence to a healthy dietary pattern had a reduced risk of dementia. In paper IV, we found associations between higher adherence to a low-fiber/high-alcohol dietary pattern and thinner cortical thickness (a marker of neurodegeneration), and associations between higher adherence to a Mediterranean-like dietary pattern and better white matter microstructural integrity (an early marker of cerebrovascular alterations). Conclusion: The findings from this thesis provide insights on dietary intake among older adults, and dietary patterns that may influence the risk of developing dementia.