Abnormal Pressure Passive Dilatation of Cerebral Arterioles in the Elderly With Isolated Systolic Hypertension

The aim of this study was to investigate the cerebrovascular adaptability to 2 sequential pressor stimuli in elderly patients with isolated systolic hypertension. Ten healthy elderly normotensive subjects (68 to 82 years), 10 elderly subjects with isolated systolic hypertension (63 to 82 years), and 10 young normotensive subjects (24 to 40 years) took part in the study. A pressor reaction, using sequential cold pressor and handgrip stimulation, was induced. The cerebrovascular response to the pressor stimulation was measured by transcranial Doppler determination of the mean flow velocity in the middle cerebral arteries. In all of the subjects, blood pressure increased during handgrip (+12 mm Hg, P