RELATIONSHIP BETWEEN SYSTEMIC HEMODYNAMICS AND AMBULATORY BLOOD-PRESSURE LEVEL - ARE SEX-DEPENDENT

Sex-related differences in systemic hemodynamics were analyzed by mean s of cardiac index and systemic vascular resistance according to the l evel of daytime ambulatory blood pressure. In addition, we assessed th e relations between ambulatory blood pressure measurements and systemi c hemodynamics namics in male and female patients. We prospectively in cluded 52 women and 53 men referred to our unit for evaluation of arte rial hypertension. Women and men were grouped according to the level o f daytime mean arterial pressure: <110 or greater than or equal to 10 mm Hg. Patients underwent noninvasive evaluation of resting hemodynami cs (impedance cardiography) and 24-hour ambulatory blood pressure moni toring. Compared with women men with lower daytime blood pressure had a 12% higher systemic vascular resistance index (P=NS) and a 14% lower cardiac index (P<.02), whereas men with higher daytime blood pressure had a 25% higher vascular resistance (P<.003) and a 21% lower cardiac index (P<.0004). Furthermore, in men systemic vascular resistance cor related positively with both daytime and nighttime systolic and diasto lic blood pressures, whereas cardiac index correlated negatively only with daytime diastolic blood pressure. In contrast, women did not exhi bit any significant correlation between hemodynamic parameters and amb ulatory blood pressure measurements. In conclusion, sex-related differ ences in systemic hemodynamics were more pronounced in the group with higher daytime hypertension. The relations between systemic hemodynami cs and ambulatory blood pressure level depended on the sex of the pati ent. In men a progressive circulatory impairment underlies the increas ing level of ambulatory blood pressure, but this was not observed in w omen.