Nocturnal hypertension

The article was written by MSc La Thi Thuy - Interventional Cardiologist, Cardiology Center - Vinmec Central Park International General Hospital

Physiologically, blood pressure during the day will fluctuate in a pattern: blood pressure is usually lower at night during sleep, begins to rise a few hours before waking, blood pressure will continue to rise during the day, often reaching peaks in the mid-afternoon, then in the late afternoon and evening, blood pressure begins to drop again.

1.What is nocturnal hypertension? Nocturnal hypertension was defined as mean nighttime blood pressure (from bed to waking) ≥ 120/70 mmHg (or > 110/65 mmHg according to the 2017 ACC/AHA update). For a normal healthy person, blood pressure at night is 10-20% lower than during the day.
2. Causes and consequences of nocturnal hypertension Blood pressure in the body is partly regulated by the autonomic nervous system, the normal pattern of which is higher blood pressure during the day and lower at night.
In case of abnormal blood pressure patterns, such as high blood pressure at night or early in the morning, it is possible that you have a health problem. May be related to the following conditions:
Uncontrolled high blood pressure Sleep apnea syndrome Kidney disease Diabetes mellitus Thyroid problems Nervous system abnormalities: insomnia, confusion Cognitive dysfunction, senility, post-stroke patients Cardiovascular disease Asians are more likely to have nocturnal hypertension due to a high-salt diet and greater sensitivity to salt. In patients with hypervolemia (high salt intake), based on urinary sodium excretion pressure, blood pressure is not only elevated during the day but also elevated at night to increase sodium excretion from the kidneys.
Increased salt sensitivity due to impaired renal function, due to sympathetic hyperactivity and activation of the RAA system. These processes are further advanced by aging, stress, obesity, diabetes, and sleep disorders (insomnia and sleep apnea syndrome).

Nocturnal hypertension may be the first manifestation of hypertension as a consequence of sympathetic hyperactivity and is often associated with cardiovascular events (stroke, coronary artery disease, heart failure) or injury. other organ damage (renal failure, cognitive impairment, and peripheral artery disease) because it goes undetected for a long time.
In addition, nocturnal hypertension can be an advanced stage of hypertension. The supine position during sleep increases venous return leading to increased left ventricular preload and increased left ventricular wall tension according to Laplace's law.
Circulatory volume is further increased by displacement of interstitial fluid from lower body soft tissues, which further increases preload. The combination of increased intravascular volume and increased blood pressure can lead to worsening renal function due to increased glomerular pressure and increased filtration.
In addition, factors that can influence abnormal blood pressure patterns include:
Night shift work Smoking Smoking Anxiety disorders Stress Patient is taking antihypertensive medication but is Short duration of action < 24 hours

Nocturnal hypertension is diagnosed by continuous blood pressure monitoring (Holter blood pressure) with at least 6 blood pressure measurements during the night. The 24-hour BP change generally follows a pattern, with a peak in the early morning and a decrease at night, known as a depression.
There is a difference in the diagnostic threshold: for the US guidelines, nocturnal blood pressure is defined as the mean blood pressure during the night ≥ 110/65 mmHg. For European guidelines this figure is 120/70 mmHg.
Blood pressure fluctuation is defined as the percentage of blood pressure drop during the night, there are 4 levels: Deep depression (reduce > 20%), depression (decrease 10-20%), loss of valley (decrease 0-10%) , reverse or increase (decrease < 0%).

To date, it has not been possible to determine which drug class or time of administration is favorable on nocturnal hypertension. However, the treatment of choice in this patient population may be long-acting drugs.
The benefit of conversion to systolic blood pressure remains controversial as this oscillation may be associated with hypoxemia, a reduction in coronary perfusion that can lead to cardiovascular and cerebral events especially in the elderly. age.
Goals: After controlling daytime blood pressure <130 mmHg, goal of evening BP treatment <110/65 mmHg.
Nocturnal hypertension is strongly associated with increased circulating volume and increased activity of the autonomic nervous system and renin-angiotensin system and associated factors. Therefore, this is the main goal in the treatment of nocturnal hypertension.
Volume overload: Salt restriction, diuretics, aldosterone antagonists, ARNI, SGLT2 inhibitors Advanced vascular disease: Calcium channel blockers alone or in combination with Renin-angiotensin system inhibitors Increase systemic activity Sympathomimetic : Beta/alpha blocker, renal neurectomy, especially in patients with sleep apnea Insomnia: using melatonin to regulate sleep Vinmec International General Hospital is one of the hospitals that not only ensures Professional quality assurance with a team of leading medical doctors, a system of modern technological equipment. The hospital provides comprehensive, professional medical examination, consultation and treatment services, with a civilized, polite, safe and sterile medical examination and treatment space. Customers when choosing to perform tests here can be completely assured of the accuracy of test results.