Blood pressure variability as a risk factor.

Blood pressure variability is clinically relevant because of the evidence that the degree of blood pressure fluctuation may independently contribute to organ damage and to the cardiovascular risk of hypertensive patients. This review will focus on the evidence available to support this concept. As such, data obtained from cross-sectional studies, longitudinal studies in humans and experimental studies in animals will be discussed. The possibility of antagonizing an excessive degree of blood pressure variability by administering drugs to provide a long-lasting and smooth antihypertensive action will also be discussed, as will the usefulness of mathematical indices aimed at quantifying the homogeneity of the blood pressure reduction by treatment.