Ambulatory blood pressure measurements, prognostic implications

Repeated measurements of the arterial pressure made in free ranging non-hospitalized individuals, termed "ambulatory blood pressures", have been shown to provide useful additional information to that obtained from measurements made in a physician's office or hospital. In general, the average of measurements made throughout the day (and night) correlates better with the severity of hypertensive target organ involvement than does the office pressure. This may be so because the ambulatory pressure is more representative of the individual's overall pressure load, and avoids the potential pressor effect of the artificial circumstances of the medical environment. We hypothesized that ambulatory pressure measurements would also provide additional prognostic information to that obtained from measurements made in the office. To test this hypothesis we have reviewed the clinical course of 1076 hypertensive patients for whom we had adequate baseline clinical information, including both office and ambulatory blood pressure readings, and at least one year of follow up. These patients were treated with standard antihypertensive therapy aimed lowering the office pressure below 140/90 mmHg, and were followed regularly in the clinic or by their primary physicians with periodic reassessment of their cardiovascular status. After a maximum of 10 years of follow up we found that individuals with higher office pressures, had a greater cardiovascular morbidity than did those with lower office pressures. Morbidity was further increased in older patients and in those who had evidence of target organ involvement or had had a prior clinical cardiovascular event.(ABSTRACT TRUNCATED AT 250 WORDS)