White-coat hypertension and sex.

OBJECTIVES: To compare, by sex, selected behavioral and biologic characteristics among normotensive, white-coat hypertensive, and essential hypertensive patients, and to assess the similarities and differences in these characteristics between men and women diagnosed as having white-coat hypertension. METHODS: The subjects of this study were 764 men (80 normotensives, 112 white-coat hypertensives, and 572 essential hypertensives) and 442 women (53 normotensives, 81 white-coat hypertensives and 308 essential hypertensives) who were a nonrandom subset of a larger cohort of patients being assessed to determine the prognostic significance of ambulatory blood pressure measurements. Physician-measured technician-measured and ambulatory (average awake and asleep) blood pressures, daytime blood pressure variability, the difference between awake and sleeping blood pressures, cholesterol levels, plasma renin activity (PRA) and anthropometric and demographic characteristics were compared across the patient classifications within each sex group and between male and female white-coat hypertensives using one-way analysis of variance. Student's t tests and chi squared analysis. RESULTS: Among men, cholesterol levels of normotensives were significantly lower than those of either white-coat or essential hypertensives (P < 0.05 and P < 0.01, respectively). White-coat hypertensives were significantly younger than the essential hypertensives. The ambulatory and technician-measured blood pressures of the white-coat hypertensives were similar to those of the normotensives, as were most measures of variability of blood pressure. Among women, there were no differences in cholesterol level; however, white-coat hypertensives had lower PRA than did the essential hypertensives (P < 0.01) In contrast to the men, women with white-coat hypertension were similar in age to those with essential hypertension, and 10 years older than normotensives (P < 0.01). The ambulatory blood pressures of white-coat hypertensives were similar to those of normotensives, but their technician-measured blood pressures were intermediate between those of the normotensive and essential hypertensive groups. The daily variability of diastolic blood pressure among the white-coat-hypertensive women was greater than that of the normotensive women and similar to that of the essential hypertensive women. For all other measures of variability, data for white-coat-hypertensive women were similar to those for the normotensive women. There was no anthropometric or demographic difference among the patients either for men or for women. White-coat-hypertensive women were older than white-coat-hypertensive men and had higher systolic blood pressures and variabilities of blood pressure (P < 0.05). They also had lower PRA. CONCLUSIONS: These results are consistent with the ideas that the phenomenon of white-coat hypertension is similar for the two sexes, women may exhibit white-coat hypertension at a greater age than do men, and women with white-coat hypertension may further exhibit a broader white-coat effect, reflected in blood pressures measured by other medical personnel.