Combined effects of gender and hypertension on the geometric design of large arteries. Sexual differences in normal and hypertensive forearm arteries

The effects of sex, hypertension, morphologic status, and heart rate were assessed on the large arteries of 46 normotensive subjects (23 men and 23 women) and 50 hypertensive patients (25 men and 25 women) by means of pulsed Doppler determination of diameter and blood velocity of the brachial artery. Compared to men, women had lower height, weight, and forearm volume (P less than 0.001), higher heart rate (P less than 0.001), and lower brachial artery diameter (P less than 0.001) both in the normotensive and hypertensive groups. Compared to normotensives, hypertensives of the same sex showed an increase in brachial artery diameter, only significant in men (P less than 0.001), and an increase in heart rate, only significant in women (P less than 0.001). The multiple regression analysis of brachial artery diameter showed significant coefficients for sex and hypertension (P less than 0.001), and for age and heart rate (P less than 0.05); the multiple regression analysis of blood velocity showed that only the coefficient of hypertension was significant (P less than 0.05). The study of first-order interactions between the independent variables revealed that effect of sex on arterial diameter did not depend on the other variables. In contrast the effects of age and heart rate were influenced by the presence or the absence of hypertension, and arterial caliber was positively related to age in normotensive subjects (P less than 0.05) but not in hypertensive patients, and negatively related to heart rate in hypertensive patients (P less than 0.001) but not in normotensive subjects.