Visit-to-visit variability: Prognostic significance?

Hypertension is the most prevalent treatable risk factor for stroke. Treatment of hypertension is based on usual blood pressure, which is evaluated by repeated measurement. When only few measurements show high blood pressure, this is considered as a background noise generally due to white coat effect. Rothwell et al. challenged this notion and presented data from post-hoc analyses of three randomized trials and one meta-analysis, where 3 parameters are strongly associated with the risk of stroke: visit-to-visit variability of systolic blood pressure, increased residual variability in treated patients, and episodic hypertension. These findings are not proof of a causal link between variability and vascular risk. However, a new window has been opened in clinical practice, giving new implications in the choice of treatment, and, for next trials, highlighting the importance of including variability and patients with episodic hypertension. © 2012 Elsevier Masson SAS.