3c.01: Adverse Prognostic Value of Persistent Office Blood Pressure Elevation in White Coat Hypertension.

OBJECTIVE Stratification of cardiovascular (CV) risk is of fundamental importance in white coat hypertension (WCH) to identify individuals in need of closer follow up and perhaps antihypertensive drug treatment. DESIGN AND METHOD In subjects representative of the general population of Monza (Italy), the risk of CV and all-cause mortality was assessed over 16 years in stable and unstable WCH individuals, i.e, those in whom ambulatory BP normality was associated with a persistent or non persistent office BP elevation at two consecutive visits, respectively. Data were compared with those from an entire normotensive group, i.e ambulatory and persistent office BP normality. RESULTS Compared to the normotensive group, the risk of CV and all cause death was not significantly different in unstable WCH, whereas in stable WCH the risk was increased also when data were adjusted for baseline confounders, including ambulatory BP(hazard ratio 12.39 p = 0.0021 for CV, and 1.91 p = 0.0178 for all cause death). At a multivariable analysis, office BP was among the factors indipendently predicting death, and results were superimposable with use of Monza population-and guidelines-derived cutoff values for ambulatory BP normality (125/79 and 130/80 mmHg, respectively). CONCLUSIONS Thus, only when office BP is persistently elevated does WCH reflect the existence of an abnormal long term mortality risk. This means that in WCH office BP is prognostically relevant and that repeated collection of office BP values should be regarded as necessary.