[Noninvasive ambulatory monitoring of arterial pressure in hypertensive patients: inside or outside the hospital?].

To investigate whether hospitalization may influence the circadian rhythm of blood pressure (BP), 15 untreated patients with essential hypertension underwent noninvasive ambulatory blood pressure monitoring twice, at home and in the hospital, in a random order, 11 days apart. During the hospital session, which took place on the ninth day of hospitalization, patients were allowed to move freely in the hospital area, to receive visits by friends and relatives and to engage in social activities with other inpatients. Home sessions were performed during a usual working day in 14 of 15 patients. Average 24-hour systolic/diastolic BP was 151/93 mmHg (DS 19/10) at home and 154/93 mmHg (DS 21/7) in the hospital; average daytime (6am-10pm) values were 155/97 mmHg (DS 19/10) at home and 157/96 mmHg (DS 20/5) in the hospital; average night-time (10pm-6am) values were 146/88 mmHg (DS 21/12) at home and 150/89 mmHg (DS 23/10). These values did not show any statistical differences (analysis of variance) due to status (home vs hospital), period or sequence. The hourly BP averages of the hospital recording did not differ significantly from the corresponding averages of the home recording. The correlation between hospital and home 24-hour averages of systolic and diastolic BP was close (r = 0.87 and r = 0.78, respectively; p less than 0.01). The chronobiological analysis (single cosinor) showed a statistically significant circadian rhythm of systolic BP in 10/15 patients at home and in 8/15 patients in the hospital (p = NS), and a statistically significant rhythm of diastolic BP in 9/15 patients at home and in 10/15 patients in the hospital (p = NS).(ABSTRACT TRUNCATED AT 250 WORDS)