Interaction of food patterns, vascular brain changes, brain network organization and cognition in a vascular risk population

Abstract

Cerebral small vessel disease (CSVD) contributes to cognitive deterioration and functional impairment among the elderly population. CSVD is characterized by several imaging markers, including white matter hyperintensities (WMH) and cortical thickness. Given that a majority of older individuals exhibit signs of CSVD on brain MRI, it becomes imperative to identify risk factors and implement preventive mechanisms to promote successful aging. This thesis focused on the investigation of WMH as imaging marker of CSVD in order to gain insights into the disease. The research involved the data analysis from a large, population-based cohort to quantify CSVD markers and assess microstructural brain damage. The first part of the thesis revealed several important findings regarding the association between the prevalence and location of WMH and other imaging characteristics. The findings from study 1 revealed that cortical regions with a higher proportion of connections to WMH demonstrated reduced thickness, suggesting a direct structural link between WMH burden and cortical thinning. In study 2, the white matter surrounding WMH exhibited an increase in free-water, indicating compromised microstructural integrity. Notably, the damage to the white matter was most pronounced in the closest proximity to the WMH, emphasizing that WMH is the end stage of a gradually deteriorating white matter. These findings shed light on the intricate relationship between WMH, cortical thinning and microstructural abnormalities in CSVD and contribute to our understanding of the disease’s underlying mechanisms. The second part of the thesis delved into the clinical aspects of CSVD and microstructural brain damage, with specific focus on the role of nutrition and coffee consumption. A food-frequency questionnaire was utilized to assess adherence to different dietary patterns, and nutritional behavior was then associated with imaging markers of brain structure and cognition. The findings of study 3 unveiled the associations between nutritional behavior, brain structure and cognitive function. One notable result was the link between healthy nutrition and a reduced risk of metabolic syndrome, which, in turn, contributed to the preservation of brain structure. Similarly, the cognitive performance was significantly better in individuals with a healthier diet. In study 4, it was demonstrated that a moderate coffee consumption was associated with preserved white matter structure and higher cortical thickness. The findings of studies 3 and 4 emphasize the significance of nutrition in maintaining brain health and suggest that adopting a healthy diet may serve a protective factor against CSVD-related deterioration.