OVERVIEW

What is hypertension?

Hypertension, as the name suggests, refers to blood pressure exceeding the normal range.

Hypertension is a very common chronic disease and one of the most important risk factors for many cardiovascular diseases. Clinically, it is mainly characterized by elevated systemic arterial pressure^[1].

If a normal adult occasionally has a high blood pressure reading, there is no need to worry too much. They can remeasure after resting quietly for at least 20 minutes or take multiple measurements over several days. Generally, if systolic blood pressure is consistently above 140 mmHg or diastolic blood pressure is above 90 mmHg in three separate measurements (on different days) without taking antihypertensive medication, hypertension should be suspected^[1].

On November 13, 2022, the "Chinese Guidelines for the Clinical Management of Hypertension" (referred to as the "Guidelines"), jointly formulated by the National Center for Cardiovascular Diseases and other authoritative institutions, recommended lowering the diagnostic threshold for hypertension in Chinese adults to systolic blood pressure ≥ 130 mmHg and/or diastolic blood pressure ≥ 80 mmHg^[4].

Once diagnosed with hypertension, it is necessary to actively control blood pressure through lifestyle changes and medication.

If blood pressure is poorly controlled, it can damage blood vessels, the heart, brain, kidneys, eyes, and other organs, leading to various complications, affecting the patient's quality of life, and even causing death.

Hypertension is divided into two main categories: primary hypertension and secondary hypertension.

• Primary hypertension is more common and usually requires lifelong treatment to control blood pressure.
• Secondary hypertension, if diagnosed and treated early, may be curable in some patients.

Is hypertension common?

Yes.

From 2012 to 2015, the prevalence of hypertension among Chinese residents aged 18 and above was 27.90%, meaning that nearly 28 out of every 100 Chinese residents may have elevated blood pressure^[2].

Many people do not fully understand the dangers of hypertension, and even fewer adhere to medical advice and take medication regularly. Less than half of patients achieve good blood pressure control.

Therefore, the current situation of hypertension in China is characterized by "three highs and three lows": high incidence, high disability rate, high mortality rate; low detection rate, low medication adherence, and low control rate.

What are the types of hypertension?

Based on etiology, hypertension can be divided into two main categories: primary hypertension and secondary hypertension^[1]:

Primary hypertension:

Primary hypertension refers to systolic blood pressure above 140 mmHg or diastolic blood pressure above 90 mmHg without taking antihypertensive medication. It is influenced by both genetic and environmental factors and generally requires lifelong medication to control blood pressure. If blood pressure remains poorly controlled for a long time, it may damage the structure and function of vital organs such as the heart, brain, and kidneys, eventually leading to organ failure.

Primary hypertension accounts for the vast majority of hypertension cases, with about 95% of hypertension being primary^[1]. Therefore, when people generally refer to hypertension, they usually mean "primary hypertension" of unknown cause.

Secondary hypertension:

Secondary hypertension refers to elevated blood pressure caused by certain identifiable diseases or factors, such as kidney disease, renal artery stenosis, hyperthyroidism, primary aldosteronism, pheochromocytoma, Cushing's syndrome, or drug effects^[1].

In treating secondary hypertension, if the underlying cause is cured early, blood pressure may significantly decrease or even return to normal. Without treating the underlying cause, simply lowering blood pressure is often ineffective. Therefore, early diagnosis and active treatment can improve cure rates and prevent disease progression.

SYMPTOMS

What are the symptoms of high blood pressure?

Most patients with high blood pressure show no obvious symptoms in the early or mild stages and often only discover it during blood pressure measurements. This is precisely why hypertension is so dangerous—by the time complications like heart attacks or strokes occur, accompanied by symptoms such as dizziness or headaches, it is often too late.

Therefore, even healthy adults should develop the habit of regularly measuring their blood pressure to stay informed. If abnormal blood pressure is detected, seek medical attention promptly to avoid serious complications.

• Some hypertensive patients may experience dizziness or headaches, possibly related to cerebrovascular spasms.
• Some may have symptoms like chest tightness or shortness of breath, which could result from decreased heart diastolic function.
• Others may feel palpitations or discomfort, possibly due to the heart needing greater contraction force to pump blood.

However, these symptoms alone do not confirm hypertension—blood pressure monitoring is necessary for diagnosis. If symptoms persist even after blood pressure normalizes, seek medical evaluation to rule out other conditions.

What are the consequences of high blood pressure?

If left uncontrolled for a long time, hypertension can cause persistent damage to blood vessels and multiple organs, with the heart, kidneys, eyes, and brain being the most vulnerable.

1. Heart damage:

   • Chronic hypertension can stimulate myocardial cell hypertrophy and interstitial fibrosis, leading to left ventricular hypertrophy and dilation, resulting in hypertensive heart disease (structural and functional changes caused by high blood pressure).
   • Left ventricular hypertrophy also reduces coronary blood flow reserve, causing myocardial ischemia during increased oxygen demand (e.g., intense exercise).
   • Hypertensive heart disease often coexists with coronary atherosclerosis, increasing the risk of myocardial infarction.

2. Brain damage:

   • Long-term hypertension can cause cerebral blood vessel ischemia and degeneration, forming microaneurysms that may rupture and lead to cerebral hemorrhage.
   • Hypertension accelerates cerebral atherosclerosis; ruptured plaques can trigger cerebral thrombosis, causing strokes.

3. Kidney damage:
   Chronic hypertension can cause glomerular necrosis, leading to kidney failure, especially in diabetic patients. Malignant hypertension (sudden, severe blood pressure spikes) can rapidly progress to kidney failure or even death.

4. Eye damage:
   Prolonged hypertension may cause retinal arteriole spasms and hardening. Sudden blood pressure spikes can lead to retinal hemorrhage or even blindness.

Although hypertension poses severe risks, standardized treatment can effectively control blood pressure in most cases, with some secondary hypertension even being curable. Maintaining blood pressure within a healthy range significantly reduces the risk of these complications.

CAUSES

What Causes Hypertension?

Secondary hypertension may result from the following causes^[3]:

1. Kidney diseases: Glomerulonephritis, chronic pyelonephritis, renal artery stenosis, renal tumors, etc.
2. Endocrine disorders: Pheochromocytoma, primary hyperaldosteronism, Cushing's syndrome, etc.
3. Cardiovascular conditions: Aortic valve insufficiency, aortic coarctation, Takayasu's arteritis, etc.
4. Brain disorders: Brain tumors, traumatic brain injury, brainstem infections, etc.
5. Medications: Oral contraceptives, antidepressants, glucocorticoids, etc.
6. Others: Obstructive sleep apnea hypopnea syndrome (snoring or breathing pauses during sleep, daytime drowsiness).

The exact cause of primary hypertension remains unclear, but it is closely associated with the following risk factors^[1]:

1. Genetics: Hypertension has a strong familial tendency. If parents have hypertension, their children face a significantly higher risk.

2. Lifestyle habits:

   • Diet: Sodium intake is positively correlated with elevated blood pressure, so hypertensive patients should limit daily salt intake.
   • Smoking: Smoking severely damages blood vessels, posing greater risks for hypertensive individuals and significantly increasing the likelihood of heart attacks and strokes. Quitting smoking and avoiding secondhand smoke are essential.
   • Alcohol: Substances in alcohol can narrow or block blood vessels, forcing blood to flow under higher pressure, thereby raising blood pressure.

3. Stress: Chronic psychological stress or negative emotions like anxiety, tension, and depression can easily elevate blood pressure.

4. Weight: Weight gain is a major risk factor for hypertension. Studies show that individuals with abdominal obesity (fat mainly accumulated around the abdomen) are more prone to hypertension.

How Does Hypertension Develop?

Three main mechanisms contribute to elevated blood pressure:

1. Increased cardiac output (more, faster, or stronger blood flow):
   For example, during intense exercise, emotional stress, or hyperthyroidism (an endocrine disorder), the heart beats harder, pumping more blood at a faster rate, naturally raising blood pressure.
2. Reduced arterial flexibility and elasticity:
   Decreased arterial elasticity leads to increased pulse pressure. In elderly individuals with atherosclerosis, blood vessels lose their normal elasticity, like rusted or aging pipes, unable to expand with blood flow, resulting in higher blood pressure—often manifesting as elevated systolic pressure.
3. Increased blood volume in circulation:
   In patients with impaired kidney function, sodium and water retention increases blood volume, raising blood pressure. This is akin to increased water pressure in a pipe when more water is added.
   High salt intake elevates sodium levels in the blood, requiring more water to dilute it, thereby increasing blood volume and pressure.

Any of these three factors can raise blood pressure. Managing hypertension involves addressing them—for example, some medications dilate blood vessels, while reducing salt intake decreases blood volume.

Is Hypertension Related to Cervical Spondylosis?

For most people, hypertension is unrelated to cervical spondylosis—they simply happen to have both conditions.

One subtype of cervical spondylosis, sympathetic cervical spondylosis, may cause dizziness, headaches, palpitations, and other symptoms resembling hypertension. In rare cases, compressed joints may irritate surrounding sympathetic nerves, triggering vascular spasms and temporary blood pressure elevation. However, this type of cervical spondylosis is very uncommon.

DIAGNOSIS

How is hypertension diagnosed?

In adults, hypertension is diagnosed if systolic blood pressure is consistently above 140 mmHg and/or diastolic blood pressure is consistently above 90 mmHg, measured on three separate occasions^[1].

In most cases, hypertension is primary (essential) hypertension.

If a patient's symptoms or manifestations lead a doctor to suspect secondary hypertension, further tests may be recommended to confirm the diagnosis.

What tests are needed if hypertension is suspected?

First, the doctor will inquire about health status, smoking history, alcohol consumption, and family history. Additional tests may also be recommended to confirm the diagnosis and assess overall health.

• Blood tests: Measure kidney function, blood sugar, lipid levels, etc. High hemoglobin increases blood viscosity, raising the risk of thrombosis.
• Urine tests: Evaluate kidney function.
• Electrocardiogram (ECG): Assess potential heart damage or complications.
• Echocardiogram: Check for structural effects of high blood pressure on the heart.
• Fundus examination: Detect retinal vascular changes to assess systemic arterial impact.

How is the severity of hypertension determined?

First, hypertension is classified into three grades—the higher the grade, the greater the risk.

• Mild (Grade 1): Systolic 140–159 mmHg or diastolic 90–99 mmHg.
• Moderate (Grade 2): Systolic 160–179 mmHg or diastolic 100–110 mmHg.
• Severe (Grade 3): Systolic ≥180 mmHg or diastolic ≥110 mmHg.

If systolic and diastolic pressures fall into different grades, the higher grade applies.

Second, additional risk factors increase danger:

• Risk factors: Male >55 years, female >65 years, smoking, alcohol, diabetes, hyperlipidemia, family history of cardiovascular disease, obesity, physical inactivity, hyperhomocysteinemia.
• Organ damage: Left ventricular hypertrophy, kidney dysfunction, carotid artery thickening/plaque, retinopathy.
• Hypertension-related diseases: Cerebrovascular disease, peripheral artery disease, cardiovascular disease, kidney disease, diabetes.

Generally, organ damage or related diseases indicate high risk, requiring aggressive treatment. Grade 3 hypertension is considered very high risk.

Is uncontrolled blood pressure resistant hypertension?

Not necessarily.

Resistant hypertension is defined as blood pressure remaining above 140/90 mmHg despite lifestyle changes and taking maximally tolerated doses of three antihypertensive drugs (including a diuretic) for at least 4 weeks, or requiring four drugs to control. It’s more common in older, obese, diabetic, or kidney disease patients^[2].

However, "resistant hypertension" requires ruling out "pseudo-resistant" causes first:

1. Incorrect measurement: Improper posture, wrong cuff size, etc.
2. Medication issues:
   • Irregular dosing or non-adherence.
   • Suboptimal drug selection/dosing or combination.
   • Use of blood pressure-raising drugs (e.g., oral contraceptives, steroids).
3. Unhealthy lifestyle/uncontrolled risk factors: High salt intake, obesity, smoking, heavy drinking, hyperlipidemia, chronic stress, insomnia.
4. Other causes:
   • Kidney dysfunction.
   • Chronic pain.
   • Poorly managed anxiety/depression.

Only after excluding these factors can resistant hypertension be diagnosed.

Even if diagnosed, patients should not lose hope. Specialized hypertension clinics can adjust treatment plans and lifestyle while ensuring strict medication adherence.

TREATMENT

Is treatment necessary for diagnosed hypertension?

Yes.

In the early stages or mild cases of hypertension, patients often show no obvious symptoms, leading some to believe that treatment is unnecessary. However, once symptoms become noticeable, they are often accompanied by life-threatening conditions such as sudden heart attacks, heart failure, or strokes. Hence, hypertension is also called the "silent killer."

In addition to medication, managing hypertension requires lifestyle changes, such as a low-salt, low-fat diet, weight loss, increased exercise, and maintaining a regular schedule, all of which can help lower blood pressure to some extent.

Which department should I visit for hypertension?

Generally, you should see a cardiologist or visit a hypertension clinic. If you experience dizziness, you may consult a neurologist; for proteinuria, a nephrologist; for electrolyte imbalances, an endocrinologist; and for blurred vision, an ophthalmologist.

How is primary hypertension treated?

• Lifestyle modifications: Recommended for all hypertensive patients. This includes a low-salt, low-fat diet, increased physical activity, weight loss, quitting smoking and alcohol, reducing stress, and maintaining a regular routine.
• Antihypertensive medication: There are various types of blood pressure-lowering drugs, each with different effects. Patients should consult a doctor to choose the most suitable medication. Do not self-medicate with over-the-counter drugs or blindly trust recommendations from pharmacy staff or other patients.
• Managing other chronic conditions: If you have diabetes, hyperlipidemia, hyperuricemia, or other chronic diseases, they should also be treated to prevent complications like cardiovascular diseases, kidney diseases, or eye conditions, thereby improving quality of life.
• Treating complications of hypertension: If complications have already developed, merely controlling blood pressure is insufficient. Active treatment of these complications is crucial to minimize damage and maintain a good quality of life.

How is secondary hypertension treated?

• Treating the underlying cause: The disease causing hypertension is called the "primary condition." Treating it addresses the root cause of secondary hypertension.
• Antihypertensive medication: If the primary condition is difficult to cure in the short term or has caused irreversible hypertension, blood pressure-lowering drugs are necessary to control it.

Other treatments are similar to those for primary hypertension.

Can hypertension be cured?

Primary hypertension (not caused by another disease) cannot be cured. Most patients require long-term medication to control blood pressure. Some mild or early-stage hypertensive patients may normalize their blood pressure through weight loss, dietary improvements, and increased exercise, but they must maintain a healthy lifestyle to sustain normal blood pressure.

Secondary hypertension (caused by another disease) can potentially be cured if detected and treated early, provided the underlying condition is fully resolved.

Why hasn't my blood pressure dropped after taking medication?

Lowering blood pressure too quickly is not ideal. Typically, blood pressure gradually normalizes within days to months of starting medication. Thus, not seeing an immediate drop in blood pressure after a few days is normal, as the drug concentration in the blood has not yet reached therapeutic levels—this does not mean the medication is ineffective.

If blood pressure remains uncontrolled after a month of consistent medication, consult your doctor to adjust the treatment plan.

Additionally, it is important to follow your doctor's instructions strictly—do not alter dosages or skip doses. Maintaining a healthy lifestyle while on medication is also essential.

DIET & LIFESTYLE

What should hypertensive patients pay attention to in their diet?

• Reduce sodium intake: In addition to table salt, foods with excessively high salt content such as pickles, cured meat, and fermented bean curd (also called tofu cheese in some places) should also be consumed sparingly.
• Reduce fat intake: Eat less or avoid fatty meat and animal organs, and reduce daily cooking oil usage.
• Quit smoking and limit alcohol: Excessive alcohol consumption can worsen hypertension, and smoking may increase disease risks for hypertensive patients.

What should hypertensive patients pay attention to in daily life?

• Weight management: Overweight or obese patients should actively control their weight within the normal range, as weight loss benefits hypertension, diabetes, and abnormal blood lipids.
• Emotional control: Anger, irritability, tension, and excessive stress are detrimental to blood pressure control. Maintaining a balanced and relaxed mindset is essential for effective management.
• Regular exercise: Exercise helps with weight loss, improves cardiovascular adaptability, and stabilizes blood pressure. It is recommended to exercise 3–5 times a week for about 30 minutes each session. Hypertensive patients should avoid intense workouts and opt for aerobic activities like jogging, brisk walking, swimming, or tai chi.

When should hypertensive patients seek medical attention?

Abnormally high blood pressure: When systolic blood pressure exceeds 180 mmHg or diastolic blood pressure exceeds 120 mmHg, it is a critical condition for most people. Untreated, it may be life-threatening. In such cases, bring your usual antihypertensive medication and seek emergency care immediately.

If severe headaches, blurred vision, difficulty breathing, or similar symptoms persist after ruling out medication side effects, organ damage due to hypertension may be occurring, requiring immediate medical attention.

How to measure blood pressure with an electronic monitor?

• Avoid smoking, drinking alcohol, or consuming coffee for at least 30 minutes before measurement. Empty your bladder beforehand.
• Rest quietly for at least 5 minutes before measuring.
• Stay silent during measurement, preferably sitting with feet flat and the arm to be measured resting on a table.
• Locate the brachial artery at the elbow (a pulsating vessel slightly toward the inner side of the elbow crease). Position the center of the cuff's airbag over the artery, ensuring the cuff is at heart level.
• Measure on bare arms by rolling up sleeves. The cuff should neither be too tight nor too loose—adjust so one or two fingers can fit between the cuff and arm.
• Press the "Start" button to begin. Most monitors display systolic (higher number), diastolic (lower number), and pulse rate.

How do smoking and alcohol affect blood pressure?

Excessive alcohol worsens hypertension, and smoking increases disease risks for hypertensive patients^[2].

Alcohol contains vasoconstrictive substances that narrow or block blood vessels, forcing blood to flow under higher pressure and raising blood pressure.

Smoking severely damages blood vessels, posing greater risks for hypertensive patients, significantly increasing the likelihood of heart attacks and strokes. Quitting smoking and avoiding secondhand smoke are crucial.

PREVENTION

Can hypertension be prevented? How to prevent it?

The cause of primary hypertension is unknown, making it difficult to prevent. However, the risk can be reduced by avoiding risk factors:

• Maintain a balanced diet, low in salt and fat, and consume plenty of fresh vegetables and fruits.
• Quit smoking and drinking, and avoid exposure to secondhand smoke.
• Exercise regularly and maintain a healthy weight.
• Reduce mental stress and maintain psychological balance.
• Patients with diabetes or hyperlipidemia should strive to control blood sugar and lipid levels.
• Take medications as prescribed by a doctor and avoid misuse of drugs.

Prevention of secondary hypertension:

• Actively treat underlying conditions that may cause elevated blood pressure.
• Maintain a healthy lifestyle and monitor blood pressure regularly.