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Circadian variation in blood pressure: dipper or nondipper
1Département de Pharmacologie, Centre de Recherche, Centre Hospitalier de l'Université de Montréal, Quèbec, Canada. pierre.larochelle@umontreal.ca
Insights
Cardiovascular events often occur after waking due to blood pressure surges. Certain medications, like long-acting angiotensin II receptor blockers, may help manage this morning blood pressure increase.
Area of Science:
- Cardiovascular Medicine
- Chronobiology
- Pharmacology
Background:
- Increased cardiovascular events post-awakening highlight the importance of cardiovascular disease chronopathology.
- Blood pressure exhibits circadian rhythms, decreasing during sleep and surging upon waking.
- This morning surge is linked to endocrine and hematologic changes potentially triggering cardiovascular events.
Purpose of the Study:
- To investigate the relationship between circadian blood pressure patterns and cardiovascular events.
- To explore the role of antihypertensive medications in modulating morning blood pressure surges.
- To clarify pathophysiologic processes underlying cardiovascular chronopathology.
Main Methods:
- Observational studies on blood pressure circadian variations.
- Analysis of hypertensive patients with blunted nighttime blood pressure decrease (nondippers).
- Pharmacological studies on the effects of long-acting medications on blood pressure rhythms.
Main Results:
- The absence or blunting of nighttime blood pressure decrease (nondipping) in hypertensive patients is associated with increased morbidity.
- Circadian variations in blood pressure, endocrine, and hematologic parameters are implicated in cardiovascular event onset.
- Long-acting angiotensin II receptor blockers demonstrate a 24-hour effect on blood pressure and may reduce the morning surge.
Conclusions:
- Circadian variations in cardiovascular parameters, particularly blood pressure, are critical in disease onset.
- Nondipping status in hypertension is a marker of increased cardiovascular risk.
- Pharmacological interventions targeting circadian rhythms, such as with long-acting ARBs, offer potential therapeutic strategies.
Abstract:
Awareness of an increased incidence of cardiovascular events shortly after awakening has heightened interest in the chronopathology of cardiovascular diseases. Blood pressure varies according to cycles characterized by a reduction during sleep and an increase on awakening. The surge in blood pressure coincides with the circadian nature of various endocrine and hematologic parameters that also have a putative role in triggering the onset of cardiovascular events. The nighttime decrease is absent or blunted in some hypertensive patients (termed nondippers), an effect associated with increased morbidity. Drugs can influence the effect of these circadian patterns. Research efforts are focused on clarifying an underlying pathophysiologic process that could be modified by pharmacologic or other means. Long-acting angiotensin II receptor blockers have an effect on blood pressure over 24 hours due to their long half-life, but could also limit the morning surge in blood pressure through an effect on the renin-angiotensin-aldosterone and noradrenergic systems.