PET and SPECT studies of ageing and cardiovascular risk factors for alzheimer’s disease

Abstract

Positron emission tomography (PET) and single-photon emission computerized tomography (SPECT) have been widely used to document local brain metabolism and regional cerebral blood fl ow reductions associated with ageing-related neurodegenerative disorders such as Alzheimer’s disease (AD), the most common form of dementia. Cardiovascular risk factors (CVRF), such as hypertension, diabetes, dyslipidemia, obesity, and smoking, are highly prevalent in the elderly population and have a signifi cant impact on cognitive performance. These conditions are nowadays recognized as important risk factors for AD. In this chapter, we review PET and SPECT studies which have investigated the impact of CVRF on brain functioning and evaluate how such evidence has helped to provide new insights about the pathophysiology of dementing disorders, particularly AD. We also highlight future directions in this fi eld of research, including longitudinal functional imaging studies to document changes in CVRF-related brain hypoactivity patterns, as well as PET studies assessing possible AD-like brain amyloid deposition abnormalities in proportion to the degree of cardiovascular risk in humans.