RELATION OF CIRCADIAN BLOOD-PRESSURE CHANGES TO LEFT-VENTRICULAR HYPERTROPHY IN ESSENTIAL-HYPERTENSION

Aim of the study was to answer the question whether changes in the diurnal blood pressure pattern will show a relation to hemodynamic, echocardiographic or endocrine parameters in men and women with essential hypertension. Therefore we conducted 24-h blood pressure measurements (Delmar Avionics), invasive hemodynamic measurements, and 2D-guided M-mode echocardiography in 20 female and 46 male untreated essential hypertensives. In addition, we determined noradrenaline, adrenaline, and plasma renin activity. The female and male study group were divided into two groups according to presence (>>dippers<<) or absence (>>non-dippers<<) of a nocturnal reduction of mean blood pressure (BP) by 10% or more of daytime values. In both sex groups dippers and non-dippers were characterized by similar casual blood pressure, body weight, and body surface area. No significant differences were observed between the two groups with regard to renal and systemic vascular resistance. Furthermore, endocrine parameters were comparable in both groups. However, cardiac structural adaptation in both groups revealed gender-related disparities. Female non-dippers were characterized by a higher left ventricular mass than female dippers (255 +/- 68 vs 184 +/- 81 g, p < 0,05). Yet, no significant differences were found between male dippers and male non-dippers (234 +/- 48 vs 240 +/- 54 g). Further analyses with regard to relative and posterior wall thickness showed again no significant differences between the two male groups. However, female non-dippers were characterized by a higher relative wall thickness (0.45 +/- 0.06 vs 0.39 +/- 0.06 mm, p < 0.05) and posterior wall thickness (1.1 +/- 0.1 vs 0.89 +/- 0.2 mm, p < 0.05) than female dippers. Summing up, dippers and non-dippers are hemodynamically characterized by a similar renal and systemic hemodynamic profile. However, development of left ventricular hypertrophy in female hypertensives is much more blood pressure-related than in male hypertensives.