Ambulatory Blood Pressure Monitoring in Hypertension

Ambulatory blood pressure monitoring generates a greater interest among investigators and clinicians because of its potential to 1) study the mechanisms involved in cardiovascular control in daily life (particularly if monitoring is performed on a beat-to-beat basis) and 2) improve the diagnosis of hypertension, the estimate of the patient's risk and the assessment of the efficacy of antihypertensive treatment. This paper will discuss the evidence pros and cons the latter indications of this approach. It will be shown that 24 hour blood pressure values correlate more closely than clinic blood pressure with various measures of the end organ damage of hypertension, suggesting that it may reflect better than traditional blood pressure measurements the cardiovascular consequences of this condition. Wider use of ambulatory blood pressure monitoring in the medical practice, however, must await a more clear demonstration of its prognostic importance, by longitudinal studies based on cardiovascular morbidity and mortality or on surrogate end points with undisputable clinical significance (e.g. left ventricular hypertrophy). It must also await clear definition of ambulatory blood pressure normality based on population studies. Until then ambulatory blood pressure monitoring should be employed to resolve special problems, e.g. identification of white coat hypertension and false non response to treatment.