Circadian variation in blood pressure: implications for the elderly patient.

In most people, blood pressure (BP) displays a characteristic diurnal pattern, with a decline during sleep and a sharp increase around the time of awakening. The early morning surge in BP is synchronous with an increase in the risk of catastrophic cardiovascular events, including acute myocardial infarction, sudden cardiac death, and stroke. Although most clinical investigations have centered on modulating or even preventing the morning surge, emerging data suggest that it may be important to avoid nocturnal hypotension, especially in elderly patients and in those with established atherosclerotic disease.