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[Morning rise in blood pressure: before or following awakening?]
1Medizinische Poliklinik, Universität Münster.
Insights
Morning blood pressure surges, linked to cardiovascular events, occur after waking, not during sleep. This suggests taking fast-acting blood pressure medications upon waking may be more effective than pre-sleep doses.
Area of Science:
- Cardiology
- Chronobiology
- Pharmacology
Context:
- Cardiovascular events often peak in the morning, coinciding with a sharp rise in blood pressure.
- The timing of this morning blood pressure surge relative to awakening is crucial for understanding its potential causal link to events.
- Current antihypertensive strategies may not optimally target this critical morning rise.
Purpose:
- To investigate whether the morning blood pressure increase begins before or after waking.
- To analyze the dynamics of blood pressure changes in the immediate post-awakening period.
- To inform the timing of antihypertensive medication for better cardiovascular event prevention.
Summary:
- Ambulatory blood pressure monitoring in normotensive and hypertensive individuals revealed no significant rise during sleep, but a steep increase after waking.
- Blood pressure increased significantly within the first hour post-awakening in both groups.
- The rate of blood pressure increase was related to the time between waking and getting up, with no phase difference from heart rate rises.
Impact:
- Findings suggest that rapidly acting antihypertensives administered *after* awakening, rather than long-acting ones before sleep, may be more effective in attenuating the morning blood pressure surge.
- This timing adjustment could lead to improved prevention of morning cardiovascular events.
- Individualized medication timing based on waking patterns may optimize therapeutic outcomes.
Abstract:
The coincidence of the circadian peak of cardiovascular events with the morning blood pressure rise suggests causal connections. Rapidly acting antihypertensives taken before getting up may attenuate the increase early enough, if the onset does not occur before awakening. In 111 normotensives and in 109 subjects with untreated essential hypertension ambulatory blood pressure monitoring was performed to study whether the onset of the blood pressure rise occurs before or after waking up. The individual 24 h blood pressure profiles obtained by intermittent readings at intervals of 15 minutes were synchronized by the time of waking up. The resulting blood pressure curves showed no substantial blood pressure rise during sleep, but steep increases after awakening: Within the first hour after waking up blood pressure increased from 107.3 + 11.4/62.3 +/- 9.6 mm Hg (mean + sd) to 121.4 +/- 16.0/75.3 + 12.6 mm Hg in normotension and from 124.7 + 16.0/72.7 + 12.2 mm Hg to 140.3 + 17.2/84.5 + 13.3 mm Hg in hypertension. The velocity of this increase was dependent on the lag between waking up and getting up. There was no phase difference between early morning blood pressure and heart rate rises. Thus to attenuate the morning blood pressure increase, rapidly acting drugs after awakening may be considered instead of long acting antihypertensives administered prior to sleep.