Impact of the daily blood pressure load on the development of hypertensive heart disease.

Blood pressure (BP) load is a method of data analysis for 24-hour BP recordings that calculates the percentage of elevated pressures above a defined threshold value. This paper reviews the relevance of BP load to indexes of hypertensive target organ disease and the usefulness of the load in assessing antihypertensive therapy. Studies that have assessed the range of BP load and the associations between the load and indexes of hypertensive target organ disease in untreated subjects were included in this review. Additional data from a therapeutic trial have been newly evaluated to assess the effects of lisinopril monotherapy on systolic and diastolic BP load in 30 mild-to-moderately hypertensive patients. BP load, whether taken as a percentage of elevated pressures over the day and night, or as integrated areas under the BP curve, predicts pathological indexes of hypertensive heart disease. In the therapeutic evaluation of BP load, lisinopril reduced systolic BP load from 75 to 44% (p < 0.001) and diastolic BP load from 56 to 29% (p < 0.001). The data have shown a close relationship between BP load and indexes of hypertensive disease. This finding and the ease of use in clinical therapeutic trials suggest that BP load reduction is a worthwhile parameter to follow in studies of antihypertensive drugs.