[Variations in blood pressure at rest and during the day in 40 ambulatory hypertensive patients]

Forty patients considered to be hypertensive on the basis of occasional blood pressure recordings obtained during three out-patient consultations (BP-C) underwent hourly blood pressure recordings throughout the day under standardized conditions at rest and lying down, but with normal daily activities between measurements. The average of the hourly measurements provides a basal blood pressure profile independent on non-standardizable factors of everyday life such as physical exercise and emotion without being artificially influenced by prolonged rest. The average ambulatory blood pressure (BP-A) is much lower than the BP-C. In particular, practically normal values (148-90) were observed in the group of patients with moderate but undiscutable hypertension (165/98) on the BP-C readings. During the same day, variations of 10 to more than 30% of systolic and diastolic pressures were observed in over 3/4 of the patients; the highest values were recorded between 8 and 12 o'clock in about 70% of cases, most commonly at the first reading at 8 or 9 o'clock in the morning. This study shows that large variations of blood pressure are observed during the daytime even when repeated recordings are made under standardised conditions. This method of determining the day time blood pressure profile is a different approach to the study of hypertension than that based on ambulatory measurements made with a portable blood pressure recorder.