No abstract

We used transcranial Doppler (TCD) to investigate whether there are cerebral circulation differences between young and elderly subjects in response to postprandial postural changes. Preprandial and postprandial systolic and diastolic blood pressure, heart rate, mean middle cerebral artery (MCA) velocity (V_mean MCA), systolic/diastolic MCA velocity ratio (V_s/V_d MCA) and pulsatility index (PI) were determined in 15 healthy elderly subjects (mean age 74.3 ± 6.5 years) and in 10 younger subjects (mean age 31.6 ± 7.2 years) in the supine position and after a postural change. As compared with young subjects, elderly ones showed a greater postprandial systolic pressure decline (p < 0.05) associated with a significant decrease of V_mean MCA (p < 0.05), and a greater increase of V_s/V_d and PI (p < 0.05 both). We conclude that, as compared with young subjects, elderly ones have reduced cerebrovascular adaptive response to pressure modifications induced by postprandial postural changes.