On longevity and the aging process : a magnetic resonance imaging study of the brain

Abstract

The aim of this thesis was to investigate the radiological phenotype of the human brain in familial longevity with regard to brain structure. This study was performed as part of the Leiden Longevity Study __ a study population consisting of offspring of long-lived Dutch people who are genetically predisposed to become long-lived as well and their environmentally and age-matched spouses. Dedicated MR imaging techniques were applied to study the phenotype of the human brain on the macrostructural as well as microstructural level. Both features which are most likely caused by early development and a lower susceptibility to known age-related structural brain changes on the macro- as well as microstructural level are hallmarks of the brain phenotype in longevity. The contributing mechanisms have yet to be identified but may involve homeostatic control and body function. Keeping in mind that there is a gradual transition from healthy brain aging to what is generally accepted as __normal__ brain aging and pathological brain changes as disease correlates, our study results implicate that the brains of offspring of nonagenarian siblings are less susceptible to neurodegenerative brain changes such as (vascular) dementia, Alzheimer__s disease and cerebrovascular disease. Our findings should be considered as starting points for future studies on the functional implications of the presented results and studies on the underlying pathways of brain structure preservation in human longevity.