WHITE-COAT HYPERTENSION AS A CAUSE OF CARDIOVASCULAR DYSFUNCTION

Background The increasing use of 24 h ambulatory blood pressure monito ring has allowed diagnosis of white-coat hypertension, in which blood pressures are higher on clinic measurements than on ambulatory monitor ing. Treatment is not generally thought to be necessary for this disor der. However, there is evidence that patients with white-coat hyperten sion develop renal impairment and left ventricular hypertrophy. We und ertook this study to assess whether white-coat hypertension, in the ab sence of cardiovascular structural abnormalities, is associated with c ardiovascular functional abnormalities. Methods Cardiovascular functio n was assessed by ultrasonography in three groups of patients classifi ed as normotensive, persistently hypertensive, or white-coat hypertens ive (23, 20, and 22 patients, respectively) on the basis of ambulatory blood pressure monitoring, carried out for 28 h with recordings taken every 15 min during the day and every 20 min during the night, acid c linic measurements, made with a semi-automatic oscillometric device. R esults Similar abnormalities of diastolic left ventricular function we re identified in the patients with persistent hypertension and those w ith white-coat hypertension; both groups differed in these indices fro m the normotensive group (E/A ratios 0.94 [SD 0.23], 1.06 [0.21], and 1.24 [0.31] respectively; ANOVA p<0.005). In addition, the white-coat and persistently hypertensive groups, when compared with the normotens ive group, showed similar abnormalities of elasticity, compliance, and stiffness (stiffness index 4.32 [1.90], 4.53 [1.38], and 3.27 [0.95] respectively; ANOVA p<0.05) of the large arteries. Interpretation Func tional cardiovascular abnormalities were identified in white-coat hype rtensive patients who had no identifiable structural abnormalities. Su ch functional abnormalities can be reversed by antihypertensive treatm ent. We propose that patients with white-coat hypertension might benef it from antihypertensive treatment as well as those with persistent hy pertension. This hypothesis should be addressed in prospective clinica l trials.