CURRENT ADVANCES IN THE CHRONOBIOLOGY OF BLOOD PRESSURE

OTERO-LOSADA ME; MILEI J.

Recent Advances in Cardiology

Intech Open Access Publisher

Año: 2013;

Biologic rhythms are viewed as adaptive adjustments of our ancestors to cyclic changes in their environment during the 24-h day, the month, and the year. Cycles of day and night resulting from the earth?s rotation movement around its axis have clearly influenced all life forms. Most organisms have evolved to synchronize their activities with it as an adaptive response bringing them an evolutive advantage. Some have chosen day or night, while others escaped daily temporal constraints altogether by living in constant conditions such as deep in the oceans or in natural caves [1]. Many organisms have developed biological clocks to time their metabolic processes rather than simply responding to the daily light-dark transitions. Rhythmic patterns have been observed in most biological functions and oscillations with a peak and trough have been demonstrated for many bodily functions, including arterial blood pressure, heart rate, vascular tone, coagulation, and fibrinolysis among many others [2]. Depending on cycle length, these oscillations can be circadian, infradian, ultradian, circannual or seasonal. Chronobiology adds a new dimension, namely, biologic time, to medicine. Improper blood pressure control throughout the entire 24 h can increase the risk of end-organ injury and cardiovascular events. Shallow declines in nocturnal compared with diurnal blood pressure (dipping) have been associated with cardiovascular disease [3]. A tendency of progression in the visual field defect in patients with primary open-angle glaucoma or