[Analysis of arterial pressure variability among individuals with white coat hypertension and essential arterial hypertension using blood pressure ambulatory monitoring].

OBJECTIVES

To compare patients with "white coat" hypertension (WCH) and essential hypertension for variability in blood pressure (BP) taken in the clinic.

DESIGN

Crossover study.

SETTING

La Orden Health Centre, Huelva.

PATIENTS: 126 people with light-to-moderate hypertension, de novo or not, being monitored but not treated by drugs. Two groups were formed: WCH defined by mean daily systolic and distolic pressures below 135 and 85 mmHg, and hypertension when the BP was over 140 and/or 90 mmHg.

MEASUREMENTS AND MAIN

RESULTS

BP was taken in the clinic in two periods: by day (7 a.m. to midnight) and at night (00.01 to 06.59), with readings every 15 and 30 minutes, respectively. Variability was compared by analysing: a) variability indices (VI), and b) coefficients of variation (CV) in BP. A regression test and multiple correlation was used. Both groups (hypertension and WCH) contained 63 people (average age: 53.4 +/- 10 and 50 +/- 10). No significant differences between the two groups in the VI were observed, except greater variability in the VI of the nocturnal systolic pressure of the hypertension group. The CV was higher in the WCH group for all pressures, with differences for 24-hour and day-time systolic pressure. The VI of systolic pressure correlated significantly with its overall clinical systolic pressure in the 24-hour period, with the day and night-time readings and with age in the day-time period.

CONCLUSIONS

Variability in the blood pressure of people with essential hypertension and WCH does not differ. Variability in systolic pressure shows positive correlation with clinical systolic pressure and, to a lesser extent, with age.