Implications of Cardiovascular Ageing for Cerebral Perfusion and Cognitive Performance

Abstract

The aim of this thesis is to examine how common manifestations of cardiovascular ageing, Orthostatic Hypotension and Atrial Fibrillation, affect cerebral perfusion and cognitive function in Irish adults. Associations between Orthostatic Hypotension, Atrial Fibrillation and cognitive function are examined in this thesis. In addition, mechanisms by which Orthostatic Hypotension and Atrial Fibrillation may impact on brain health are studied by examining their impact on cerebral perfusion.

Five quantitative studies are presented in this thesis, which use data from The Irish Longitudinal Study on Ageing (TILDA), a large population representative cohort study of Irish adults over the age of 50.

In this thesis, individuals with Atrial Fibrillation are found to be more likely to have Orthostatic Hypotension. In addition, Orthostatic Hypotension is found to be associated with cognitive decline in an Irish population, and cerebral haemodynamics in response to orthostasis are also impaired. While Atrial Fibrillation was not found to be robustly associated with cognitive decline, it was found to impair cerebral haemodynamics in response to orthostasis.

Impaired cerebral haemodynamics in response to standing in individuals with Orthostatic hypotension and Atrial Fibrillation demonstrated in this thesis may contribute to cognitive decline.