Value of patient-recorded home blood pressure series in distinguishing sustained from office hypertension: effects on diagnosis and treatment of mild hypertension. Bath District Hypertension Study Group.

To identify the incidence and magnitude of office hypertension and determine its effect on diagnosis and treatment, 104 patients with a systolic blood pressure greater than or equal to 160 mmHg and a diastolic blood pressure greater than or equal to 95 mmHg on three consecutive office visits recorded a home BP series with an electronic sphygmomanometer. At the fourth office visit the blood pressure was measured independently by the patient and doctor using electronic and mercury sphygmomanometers, respectively, and compared with the mean blood pressure of the home series. In 80% of patients, the fourth office blood pressure was higher than the mean blood pressure of the home series. An office rise greater than or equal to 10/5 mmHg occurred in some 60% of patients, greater than or equal to 20/10 mmHg in 36% and 30/15 mmHg in 19% of patients. Office falls in blood pressure occurred in 20% of patients but averaged 3/2 mmHg. Treatment decisions based on the mean blood pressure of the home series resulted in treatment not being started in 25 patients (24%) who would have received treatment on their fourth office blood pressures. A patient-recorded home series provides a representative sample of blood pressure distinguishing patients with sustained hypertension from those with office hypertension and reducing the over diagnosis and over treatment of mild hypertension.