Impact of nocturnal fall in blood pressure on early cardiovascular changes in essential hypertension

Objective. To evaluate in a selected population of subjects with a recent diagnosis of hypertension whether a blunted nocturnal fall in blood pressure is associated with more advanced cardiac and vascular damage. Methods. One hundred and eleven recently diagnosed and never-treated patients with mild essential hypertension underwent 24-h ambulatory blood pressure monitoring (ABPM), echocardiography and carotid ultrasonography. Results. The 78 patients with normal (> 10%) night-time fall in systolic blood pressure (SBP) and diastolic blood pressure (DBP) (dippers) were similar to the 33 patients with a small (≤ 10%) fall (non-dippers) for age, sex, body surface area, smoking habit, clinic and 24-h blood pressure. There were no differences between dippers and non-dippers in left ventricular mass index (104 versus 105 g/m²), common carotid internal diameter (5.8 versus 5.9 mm), intima-media thickness (0.66 versus 0.64 mm) and carotid plaques prevalence (25 versus 29%). Furthermore, no differences were found in the correlation of daytime and night-time SBP and DBP with left ventricular mass and carotid wall thickness. When the 77 men and 34 women were analysed separately, similar results were obtained. Conclusion. These results suggest that a blunted reduction in night-time blood pressure does not play a major role in the development of cardiovascular changes during the early phase of essential hypertension.