Current status of ambulatory blood pressure monitoring.

During the past few years, 24 h ambulatory blood pressure (BP) monitoring has become an essential tool in the management of hypertensive patients. Individuals who exhibit increases in BP only in the office setting (white coat hypertension) can now avoid unnecessary drug therapy. For patients with treated hypertension, ambulatory BP monitoring has provided a means to detect individuals at increased risk of experiencing a cardiovascular event independent of the office BP reading. Alternatives to BP monitoring, such as self-measurement in the home, do exist, but the interpretation of findings reported by patients must be scrutinized carefully to take into account the use of nonvalidated devices and the possibility of "reporting bias". Automated BP recording devices have recently been introduced into the office setting and are likely to become more commonplace over the next few years. The Canadian Hypertension Education Program recommends the assessment of hypertensive patients with ambulatory BP monitoring in accordance with specific guidelines for the diagnosis of hypertension and the detection of a white coat effect in treated patients who are having difficulty reaching target BP levels.