Cerebral CO2 reactivity, cholesterol, and high-density lipoprotein cholesterol in the elderly

Cholesterol and its subfractions play a role in the development of atherosc lerosis. Cerebral CO2 reactivity reflects the compensatory capacity of cere bral arterioles, The authors investigated the relationship between total ch olesterol, high-density lipoprotein (HDL), their ratio, and cerebral CO2 re activity in 826 participants from the Rotterdam Study. Cerebral CO2 reactiv ity increased significantly with increasing levels of HDL and decreased sig nificantly with an increasing total cholesterol/HDL ratio. This suggests th at blood lipids may also affect smaller cerebral blood vessels.