Comparison of ambulatory blood pressure and cardiovascular reflexes in elderly hypertensives, elderly normotensives and young hypertensives.

Thirteen elderly hypertensives (EH) underwent ambulatory blood pressure (BP) monitoring and measurement of cardiovascular reflexes. The results were compared with elderly normotensives (EN) and young hypertensives (YH) in studies using the same protocol. There was a greater disparity between casual systolic BP (SBP) and ambulatory awake SBP in EH than EN or YH. Variability of SBP was greater in the elderly than in the young, whilst baroreflex activity was reduced in the elderly, more markedly so in EH. Response to tilt and pressor tests were similar in EH and EN. EH showed greater changes in response to tilt and dynamic exercise than YH. The results suggest an exaggerated response to casual BP measurement in EH. The reduced baroreflex activity in EH could be associated with greater degenerative changes. The EH are exposed to greater peaks of BP than EN in response to pressor stimuli.