INVESTIGADORES
PEREZ LLORET Santiago
congresos y reuniones científicas
Título:
MORNING BLOOD PRESSURE AND HEART RATE IN DIPPER AND NON-DIPPER NORMOTENSIVE OR HYPERTENSIVE SUBJECTS.
Autor/es:
PEREZ-LLORET S; RISK M; CARDINALI D; SANCHEZ, R; RAMIREZ A
Lugar:
Milan, Italia
Reunión:
Congreso; Congreso de la Sociedad Europea de Hipertension; 2005
Resumen:
OBJECTIVE: To evaluate heart rate and blood pressure (BP) morning surge changes in normotensive (NT) or hypertensive (HT) subjects exhibiting  or not BP dipping. METHODS: This is a transversal observational study including 332 subjects. After a 24 h ABPM (Spacelabs 90207), mean blood pressure (MBP) and heart rate (HR) 24h rhythm were fitted with 12, 8, 6, 4, 3, 2 and 1.5 h harmonics (Fast Fourier Transform). Subjects were classified as hypertensive (139 subjects) if mean day-time systolic and/or diastolic BP was greater than 135/85mmHg or were on antihypertensive treatment. Daytime and nighttime periods were defined from the subjects’ logbook. The morning surge was defined as the two hours period after the subjects’ reported awakening time. Additionally, subjects were classified as non-dippers (72 NT and 51 HT) if dipping was lower than 10% of their respective day-time systolic BP. Data were expressed as Mean±SEM and analyzed by a two-way ANOVA, with hypertension diagnosis and dip status as main factors. Adjustments for age, gender, BMI and pharmacological treatment were performed. RESULTS: HT (54.0±1.2 yr) and non-dipper (53.0±1.3 yr) subjects were significantly older than NT (46.0±1.0 yr; p<0.001) and dippers (48.0±1.0 yr; p<0.005). Nighttime MBP was significantly higher in HT (95.4±0.8mmHg) as compared to NT (79.2±0.6 mmHg; p<0.001) and lower in dippers (82.9±0.5mmHg) as compared to non-dippers (91.7±0.7mmHg; p<0.001). No differences were found in HR. In hypertensive subjects, MBP surge was significantly higher in non-dippers (113.6±1.5mmHg) than in dippers (107.3±1.1mmHg; p=0.001). Similarly, HR surge was significantly higher in non-dipper (15.7±1.5bpm) as compared to dippers (12.7±1.2bpm; p=0.05). In this group of subjects (n=51), MBP surge failed to show a significant correlation with MBP rhythm amplitude or integrity (R2). In contrast,  morning HR surge showed a significant correlation with HR rhythm amplitude (r=0.5;p<0.001) and integrity (r=0.4; p=0.005). CONCLUSIONS: An impaired nocturnal BP fall seems to be associated with a higher morning BP surge in hypertensive subjects. The increased BP surge was related to the HR surge but was unrelated to BP rhythm disturbances. The increased BP surge could be the consequence of the increased sympathetic activity found in hypertension and, by this way, could explain the end-organ damage.