Relationship Between Level of Blood Pressure Measured Casually and by Portable Recorders and Severity of Complications in Essential Hypertension
The relationship of the degree of severity of cardiovascular complications, graded according to ocular funduscopic, electrocardiographic, and roentgenographic (heart size) criteria to arterial blood pressure levels was investigated in 124 patients with essential hypertension. Blood pressure levels were determined both by casual measurements and by means of a portable semiautomatic blood pressure recorder worn during the patient's normal daily activities.
Statistical analysis of the data showed a significant correlation between the overall severity of hypertensive complications and the average casual systolic and diastolic blood pressures; the correlation with the corresponding pressure readings obtained with the portable recorder, however, was significantly higher. The relationship between the average pressures obtained with the portable recorder and the severity of complications was quantitative: the higher the mean systolic and diastolic pressures, the greater the average degree of severity.
No correlation was found between severity of complications and variability of the systolic or diastolic pressures recorded by the patient or between severity and duration of hypertension as best determined from the medical history. A low but significant correlation was found with age.
Few patients with hypertensive complications had mean recorder blood pressure levels below 120/80 mm Hg. On the other hand, all the patients whose mean recorder pressures exceeded 160/100 mm Hg had some degree of hypertensive complications. Attempts to predict overall severity of hypertensive complications in individual cases from the patients' mean recorder blood pressure levels and age demonstrated that patients in class II (moderate severity) could be distinguished from those in class 0 (no hypertensive complications) with great accuracy.
The results of the study support the view that the severity of cardiovascular complications essential hypertension is mainly determined by the average level of the arterial blood pressure. It is suggested that portable recorder measurements should aid in selecting patients likely to benefit from antihypertensive therapy and in guiding such treatment.
- © 1966 American Heart Association, Inc.