Comparison of clinic and home blood pressure measurements.

The blood pressures of 26 treated hypertensive patients were monitored throughout a 4-min interview with a physician and during a further 6 min of silence. During the period of conversation, the systolic pressure did not change significantly but diastolic pressure rose by 5.6 mm Hg. During the subsequent period of silence the mean systolic/diastolic blood pressure fell by 19.7/11.3 mm Hg. After a training course, 20 of the patients measured their blood pressure at home for one week. There was no significant difference between the mean systolic pressure taken in the home and that measured after 5 min of quiet rest in the clinic. The mean clinic diastolic blood pressure after 5 min of quiet rest was 3.1 mm Hg higher than that measured at home. Since hypertensive cardiovascular complications are more closely related to home than to casual clinic measurements, and since the blood pressure after 5 min of quiet rest in the clinic closely approximates the home measurement, we suggest that clinic blood pressure be taken only after 5 min of quiet rest.