Many people with hypertension believe that taking their blood pressure once a day during the day is sufficient, but it is not. A single measurement during the day often does not reflect the true blood pressure level and does not detect the signs of high blood pressure in the early morning.
What makes blood pressure high in the morning?
Early morning hypertension stems from the diurnal pattern of blood pressure. Controlled by the body’s biological clock, blood pressure is constantly changing dynamically over a 24-hour period.
Even in people with normal blood pressure, the blood pressure level will show a more obvious circadian rhythm, which can be simply summarized as “two peaks and a valley”.
Early in the morning, after waking up, blood pressure rises significantly from 8:00 to 10:00, showing a peak, and then falls;
In the afternoon, between 17:00 and 18:00, blood pressure rises again from a trough to a peak;
At night, between 2:00 and 3:00, blood pressure is at its lowest, with another trough, and so on.
Therefore, we generally recommend that patients have their blood pressure taken at least once in the early morning. For example, home blood pressure measurements taken within one hour of waking up, before taking medication, and before breakfast can be called early morning blood pressure.
What are the risks of early morning hypertension?
Elevated blood pressure in the morning can cause serious damage to the heart, brain, kidneys, and blood vessels.
Early morning hypertension is the primary risk factor for a high incidence of cardiovascular events, and it is even more important to control early morning blood pressure in Asian populations. Epidemiological surveys show that approximately 40% of myocardial infarctions and 29% of sudden cardiac deaths occur in the early morning hours.
Early morning hypertension is also the strongest independent risk factor for stroke, with the incidence of stroke three to four times higher than at other times of the day. Therefore, it is especially important for stroke patients or those at high risk of stroke to keep their blood pressure under control in the early morning.
In addition, the relative risk of carotid atherosclerosis is increased 5-fold in patients with early morning hypertension. It may also aggravate renal impairment in patients with chronic kidney disease.
However, early morning blood pressure is not well controlled in about 60% of our patients with controlled blood pressure in the office, and is essentially a blind spot for blood pressure management. Therefore, it is imperative to recognize and manage early morning hypertension.
How to deal with the morning peak of hypertension?
For the antihypertensive treatment of early morning hypertension, there are three points to note.
The first is the rational choice of antihypertensive drugs.
Recent medical research has confirmed that long-acting angiotensin-converting enzyme inhibitors (ACEⅠ) such as lenopril, enalapril, perindopril, angiotensin II receptor antagonists such as candesartan, olmesartan, valsartan, cloxartan and long-acting calcium antagonists such as nifedipine controlled-release tablets, amlodipine, felodipine, etc. can be taken only once a day to achieve 24-hour stable blood pressure control. It is very useful to prevent blood pressure fluctuations and control the increase of blood pressure in the early morning, and can be used as the first choice of antihypertensive drugs.
The second is to grasp the correct time to take medication.
For patients with early morning hypertension, taking antihypertensive drugs around 7 a.m. can significantly inhibit the climb of blood pressure and reduce the risk of cardiovascular disease caused by increased blood pressure, so patients should take antihypertensive drugs in the early morning.
Third, drug therapy should be closely combined with non-drug therapy.
Non-pharmacological therapy focuses on limiting the intake of salt and fat, quitting smoking and alcohol, carrying out sports and maintaining an optimistic mood, which patients should do in their daily life.