Experience with noninvasive ambulatory 24-hour blood pressure recording in a community hospital

In 40 subjects (23 treated with antihypertensive medication), 24-h ambulatory blood pressure was measured with an oscillometric blood pressure monitor (Spacelabs model 90202). We studied applicability in the out-patient department with regard to patient tolerance, correlation with mercury manometer measurements, 24-h blood pressure variability and the use in detecting "white-coat" hypertension. The measurements were tolerated quite well except for complaints of sleep disturbance and local irritation from the cuff. The average percentage of missed measuring points was 9.2%. Correlation between blood pressure with the mercury manometer and the Spacelabs monitor (averages of three consecutive readings) was: systolic 0.87 and diastolic 0.73 (P less than 0.001). No evidence for systematic error between the two methods was found. Diurnal blood pressure variation was significant with an average night-time drop of 12 +/- 15 mmHg systolic and 12 +/- 11 mmHg diastolic. "Office" blood pressure measured with the Spacelabs monitor was in the hypertensive range for 28 patients (systolic greater than or equal to 160 and/or diastolic greater than or equal to 95 mmHg). Only 15 of these subjects still met the hypertension criteria on the basis of mean daytime ambulatory blood pressure values. When ambulatory blood pressures during arbitrary 3-h periods of the daytime were studied, the number of patients with established hypertension did not change. The patients with this "office" or "white-coat" hypertensive response could not be distinguished on the basis of variability in daytime blood pressure.(ABSTRACT TRUNCATED AT 250 WORDS)