[24-hour blood pressure in normotensive elderly women and elderly women with white-coat hypertension].

BACKGROUND Changes in the behavior of the circadian rhythm can be deleterious, leading to target-organ damage, which suggests that they can have a prognostic significance and, eventually, can also demand therapeutic intervention. OBJECTIVE To describe and compare the circadian rhythms of blood pressure (BP) in normotensive elderly women and in those with white-coat hypertension (WCH). METHODS A cross-sectional study was carried out in sample of 36 patients, aged 60-83 years, submitted to ambulatory blood pressure monitoring (ABPM) for a period of 24 hours. Nineteen normotensive elderly women and 17 with WHC were compared regarding the nocturnal dipping and the BP variability, morning increase in systolic blood pressure (SBP), pulse pressure, post-prandial hypotension and correlation of 24-hour BP means. The statistical analysis used the Student's t test, Chi-square test, Fisher's exact test and Pearson's linear correlation. RESULTS The elderly women with WCH presented higher levels of SBP than the normotensive ones, between 8 am-12 pm (133 +/- 8.0 mmHg vs 123 +/- 9.0 mmHg, respectively, p < 0.001). The BP variability was higher in the WCH group only during the wakefulness period (between 7 am-11 pm, p = 0.02). A positive correlation was observed between the BMI and the SBP means at night, only in the elderly women with WCH (r = 0.578; p = 0.015 and r = 0.488; p = 0.055, respectively). CONCLUSION The elderly women with WCH presented higher SBP and diastolic blood pressure (DBP) means during the wakefulness period. In the early hours of the morning, the elderly women with WCH presented significantly higher SBP means.