Essential hypertension in the elderly: circadian variation of arterial pressure

Summary

Continuous 24-hour arterial pressure (BP) recordings (Del Mar Avionics Pressurometer II) in elderly essential hypertensive patients revealed that while all patients had daytime ambulatory systolic pressure significantly lower than in the office, two different patterns emerged during the night. In 14 patients both systolic and diastolic pressures continued to fall to significantly lower lev­els than daytime ambulatory BP. However, in seven other patients, systolic pressures increased to similar levels as the office BP recording, although diastolic pressures remained unchanged. The prev­alence of clinical cardiovascular complications was 43% in those with a nocturnal drop in pressure and 100% in those patients with a nocturnal increase in pressure (x ², 6.46; p < 0.025). We conclude that, in elderly patients, outpatient office BP recording may give a misleading impression of the in­dividual’s integrated arterial pressure. The presence or absence of a nocturnal fall in pressure may be helpful in predicting a patient’s risk of developing future cardiovascular complications.