Effects of race and sex on blood pressure and hemodynamic stress response as a function of the menstrual cycle

Abstract

OBJECTIVE: To examine the influence of race and sex on responses to cardiovascular stress during two menstrual cycle phases. METHODS: Subjects were exposed to two stressors, a mirror star-tracing task and a speaking task. Blood pressure, heart rate, and impedance cardiography measures of reactivity were recorded. Women were examined both during the follicular and during the luteal phase of their menstrual cycle with men matched for the number of days between testing sessions (approximately 6 weeks). The subjects were 33 black and white women and 37 black and white men who were healthy, normotensive, and not being administered medication. RESULTS: For black women, the reactivity of the diastolic blood pressure (DBP) to the speaking task was less in the luteal phase than it was in the follicular phase, whereas for white women (and men) there was no difference between the two phases (testing sessions) (P < 0.04). Women had greater heart rate reactivities in both menstrual phases than did men (P < 0.05). During the stage of preparing to speak, black and white women had greater DBP reactivities than did men; however, their DBP responses were attenuated during the luteal phase compared with the follicular phase (P < 0.05). In reponse to the mirror star task, white men and women had greater DBP than did blacks (P < 0.05) whereas blacks had less of a decrease in stroke volume than did whites (P < 0.04). CONCLUSIONS: The present investigation confirms results from previous studies on the effects of sex and menstrual cycle on the response to hemodynamic stress. Our findings also suggest that racial differences in stress reactivity may influence this phenomenon.