Stage 1 No objective evidence of organ damage

Stage 1 | > No objective evidence of organ damage Stage 2 | > At least one sign of organ damage | > | > Left ventricular hypertrophy (X-ray, ECG, ultrasound) Retinal artery stenosis | > | > Proteinuria and/or slight elevation of serum creatinine (106~177 mmol/L) | > | > Ultrasound or X-ray shows atherosclerotic plaque (carotid, aortic, iliac, femoral arteries) Stage 3 | > Clinical manifestations of organ damage | > | > Heart: Angina pectoris, myocardial infarction, heart failure | > | > Brain: Transient ischemic attack (TIA), stroke, hypertensive encephalopathy | > Fundus: Retinal hemorrhage, exudates with or without papilledema | > | > Kidney: Serum creatinine >177 mmol/L, renal failure | > Vessels: Arterial dissection, occlusive arterial disease Section 2 Clinical Types (1) Critical Hypertension Refers to blood pressure exceeding the normal range but not yet reaching the threshold for hypertension. Critical hypertension is very common; in a recent nationwide blood pressure survey, the prevalence was 5.26%, while the prevalence of confirmed hypertension was only 6.62%. According to the 1993 WHO/ISH classification, critical hypertension—including critical isolated systolic hypertension—is categorized as a subtype of mild hypertension. Patients with critical hypertension exhibit greater blood pressure fluctuations, with more pronounced SBP elevation, resulting in a larger pulse pressure. (2) Hypertensive Emergency Hypertensive patients may experience a sudden and dramatic rise in blood pressure within a short period (hours to days), often accompanied by dysfunction of the heart, brain, and kidneys. Based on clinical presentation, it can be divided into: ① Malignant hypertension. Approximately 3%–4% of moderate to severe hypertensive patients may develop malignant hypertension, with clinical features mainly characterized by markedly elevated blood pressure. Diastolic pressure >16.9 kPa (130 mmHg), retinal hemorrhage and exudation with papilledema (Grade IV); renal insufficiency, possibly with cardiac and cerebral dysfunction. Without timely treatment, death may result from renal failure, stroke, or heart failure. ② Hypertensive crisis. Hypertensive patients experience a sharp increase in blood pressure over a short period, accompanied by symptoms such as headache, irritability, palpitations, excessive sweating, nausea, vomiting, pallor or flushing, and blurred vision. Systolic pressure can reach as high as 33.8 kPa (260 mmHg), with diastolic pressure above 15.6 kPa (120 mmHg). ③ Hypertensive encephalopathy. Along with a sudden and marked rise in blood pressure, central nervous system dysfunction appears. Clinical manifestations include severe headache, vomiting, and altered mental status. In milder cases, only irritability and confusion occur; in severe cases, seizures, epileptiform attacks, or coma may develop. (3) Senile Hypertension With advancing age, the prevalence of hypertension gradually increases. Among people aged 60 and above, 40%–45% have hypertension, half of whom have isolated systolic hypertension (i.e., systolic pressure ≥21.3 kPa (160 mmHg), diastolic pressure <12 kPa (90 mmHg)). Epidemiological observations indicate that elevated systolic pressure is one of the major risk factors for cardiovascular mortality. In senile hypertension, apart from some cases evolving from pre-senile diastolic hypertension, most cases arise due to thickening of the vascular intima and media, reduced arterial elasticity, and decreased compliance. These changes result in lower arterial distensibility during systole, allowing systolic pressure to rise. During diastole, however, the vessel cannot maintain intravascular pressure, leading to lower diastolic pressure and a wider pulse pressure. Clinically, senile hypertension exhibits the following characteristics: ① Greater blood pressure variability. ② Prone to orthostatic hypotension, especially during antihypertensive treatment. ③ Higher risk of heart failure. Section 3 Clinical Examination (1) Physical Examination In addition to routine examinations, the following should also be included: assessment of carotid and upper/lower limb arterial pulses; presence of vascular bruits in the neck and abdomen; abdominal masses, renal enlargement, and abdominal aortic pulsation; fundus examination, bilateral upper limb blood pressure, height, weight, etc. (2) Routine Laboratory Tests Complete blood count, urinalysis, fasting blood glucose, potassium, creatinine, blood urea nitrogen, cholesterol, triglycerides, chest X-ray or radiograph, electrocardiogram. (3) Other Examinations Echocardiography, microalbuminuria testing, glucose tolerance test, and blood insulin concentration measurement, etc. (4) Cardiovascular Risk Factors Individuals with obvious cardiovascular risk factors require antihypertensive treatment even if their hypertension is mild. Common cardiovascular risk factors include: age, gender (male, postmenopausal female), family history of early cardiovascular disease, elevated blood pressure, smoking, high total cholesterol, high LDL cholesterol, low HDL cholesterol, left ventricular hypertrophy, prior cardiovascular events, prior cerebrovascular events, diabetes, kidney disease, microalbuminuria, obesity, and a sedentary lifestyle. (5) Ambulatory Blood Pressure Monitoring Clinically, blood pressure is usually measured using sphygmomanometers in hospitals or at home, known as spot blood pressure monitoring. However, this method cannot reliably reflect blood pressure fluctuations or changes under daily activity and rest conditions. In recent years, portable ambulatory blood pressure monitors (ABPM) have been increasingly used clinically. The commonly used method involves indirect measurements every 15 or 20 minutes, automatically recording blood pressure and heart rate. Normal blood pressure exhibits distinct diurnal variations, with ambulatory blood pressure curves showing two peaks and one trough: nighttime blood pressure is lowest, rising rapidly after morning activities, with peaks between 6:00–10:00 and 16:00–20:00, followed by a gradual decline. Hypertensive patients’ diurnal blood pressure curves are similar, but the overall levels are higher and the fluctuations are more pronounced. The morning rise in blood pressure explains why some acute cardiovascular events, such as acute myocardial infarction, sudden death, and stroke, occur more frequently shortly after waking up. Section 4 Points to Note (1) How to Measure Blood Pressure Measuring blood pressure is relatively simple; many people think it’s easy to learn and no further study is needed. In fact, human error sometimes leads to false alarms or delays in treatment. To ensure accurate blood pressure readings, one must understand many details.

1. Issues with sphygmomanometers “To do a good job, one must first sharpen one’s tools.” When measuring blood pressure, the first question is which type of sphygmomanometer to choose. Currently, there are three types available on the market: desktop, dial, and electronic. Desktop sphygmomanometers have low error rates and are suitable for home use; in addition to the unit “millimeters of mercury,” they also display the international unit “kilopascals” (kPa, 1 kPa = 7.5 mmHg). Dial sphygmomanometers are ideal for medical personnel because of their portability and are often kept in emergency kits for outdoor use. Electronic sphygmomanometers must be regularly calibrated against desktop models, as the sensitivity of their internal sound sensors can often cause measurement errors. After purchasing a sphygmomanometer, it is essential to test it and calibrate it against a standard device; after a period of use, recalibration is necessary, otherwise measurement errors are likely to occur. A local metrology bureau once sampled sphygmomanometers used in medical institutions in the area, finding a pass rate of only 65%, indicating that calibration work still faces many problems and deserves attention.
2. Requirements for Blood Pressure Measurement What specific requirements are there for measuring blood pressure? Generally, these include environmental requirements, requirements for the person being measured, and requirements for the measurer. Environmental requirements: the environment should be quiet, with a comfortable room temperature, preferably around 21°C. Requirements for the person being measured: no eating for half an hour before measurement; eating can raise blood pressure by 0.7–1.1 kPa (5–8 mmHg); no smoking or drinking—most people’s blood pressure rises after drinking, while a few see a decrease; bowel and bladder emptying; no change in body position for 5 minutes before measurement; sit upright and remain seated for 15 minutes before measurement; if still feeling anxious, take several deep breaths. Requirements for the measurer: ① Measure blood pressure in the right upper arm’s brachial artery, as this location is convenient and representative of aortic blood pressure. Position the patient’s right upper arm extended on the table, palm up, without making a fist, with the arm at a 45° angle to the chest and parallel to the heart; the lower edge of the cuff should be aligned with the fourth intercostal space. Improper sitting posture results in higher readings, while the arm positioned below heart level yields lower readings. The lower edge of the cuff should be 2 cm above the elbow crease, otherwise it won’t properly cover the artery and readings will be too high; the sleeve shouldn’t be too tight (it’s best to remove one sleeve), as tying the cuff directly to the sleeve makes readings unreliable; after securing the cuff, there should be enough space to fit two fingers—too tight cuffs inflate readings. Also, pay attention to the stethoscope: don’t use it backward. The earpieces of the stethoscope should face forward; using it backward reduces the sound of the heartbeat, leading to inaccurate readings. Some testers place the stethoscope under the cuff, where the pressure is too great, distorting the artery and lowering diastolic readings. ② After completing the above steps, turn on the sphygmomanometer and set the maximum inflation level, inflating quickly—if too slow or uneven, readings will be inaccurate.
3. Often-overlooked blood pressure data Blood pressure consists of systolic pressure, diastolic pressure, and pulse pressure difference. When analyzing clinical significance, the latter two are often ignored; many people judge hypertension solely based on systolic pressure, perhaps because they generally equate elevated systolic pressure with hypertension. It should be understood that diastolic pressure and pulse pressure difference are even more important in preventing and treating cardiovascular diseases, especially hypertension. High diastolic pressure and small pulse pressure difference are key features of primary hypertension in young and middle-aged adults; mistakenly assuming systolic pressure is not high can have dangerous consequences. Such blood pressure patterns significantly increase the incidence of cardiovascular and cerebrovascular diseases. Pulse pressure difference, also known as pulse pressure, is another often-overlooked metric, with a normal range of 4.0–5.3 kPa (30–40 mmHg). Increased pulse pressure can be seen in aortic valve insufficiency, hypertension, aortic atherosclerosis, hyperthyroidism, severe anemia, and other conditions. Decreased pulse pressure is observed in hypotension, pericardial effusion, constrictive pericarditis, severe pericarditis, severe mitral stenosis, aortic stenosis, and severe cardiac dysfunction. (2) Spot Blood Pressure vs. Baseline Blood Pressure Blood pressure measured when the subject is completely unprepared is called spot blood pressure. Time, location, the subject’s mental state, and the attitude of medical staff can all affect spot blood pressure readings. Baseline blood pressure refers to the blood pressure of a patient in a “relatively stationary” state. For example, blood pressure measured before getting out of bed in the morning can be considered baseline blood pressure. The level of baseline blood pressure is related to the prognosis of hypertension: the higher the baseline, the worse the prognosis. Hypertensive patients’ baseline blood pressure fluctuates more than that of healthy individuals. To address the issue of large fluctuations in spot blood pressure, the following three methods can be adopted: ① The subject must be in a fully rested state, and medical staff should repeatedly measure blood pressure multiple times to more accurately reflect the true situation. ② Evidence suggests that blood pressure readings taken by medical staff are consistently higher than those measured by family members or the patients themselves; this phenomenon is often referred to as the white coat effect. In such cases, family members or patients can repeatedly measure blood pressure to correct any deficiencies in the readings. ③ Use fully automatic blood pressure recording devices to measure blood pressure. (3) Ambulatory Blood Pressure Monitoring Using ambulatory blood pressure recorders to measure blood pressure changes over a 24-hour period is called ambulatory blood pressure monitoring. Ambulatory blood pressure includes systolic pressure, diastolic pressure, mean arterial pressure, heart rate, as well as their highest and lowest values, and percentages equal to or greater than 21.3/12.6 kPa (160/95 mmHg) or 18.7/12.0 kPa (140/90 mmHg), among others. Compared with spot blood pressure, ambulatory blood pressure has the following advantages: ① It eliminates the randomness of spot measurements, avoiding the influence of emotions, exercise, eating, smoking, drinking, and other factors, thus providing a more objective and realistic reflection of blood pressure conditions. ② Ambulatory blood pressure provides more detailed blood pressure data, accurately reflecting the patterns of blood pressure changes throughout the day. ③ For patients with mild or borderline hypertension who initially show no symptoms, it increases the detection rate and enables timely treatment. ④ Ambulatory blood pressure can guide drug therapy. In many cases, it can be used to assess the effectiveness of medication, helping to select drugs and adjust dosages and administration times. ⑤ It can determine whether hypertensive patients have target organ damage (organs susceptible to hypertension-related harm). Hypertensive patients with left ventricular hypertrophy, retinal vascular lesions, or renal dysfunction tend to have smaller differences between day and night blood pressure. ⑥ It can predict the timing of sudden cardiovascular and cerebrovascular events during the day. When blood pressure suddenly rises in the early morning, cardiovascular and cerebrovascular events are most likely to occur. ⑦ Ambulatory blood pressure is important for prognosis assessment. Compared with regular blood pressure, 24-hour blood pressure The mortality rate and the incidence of first cardiovascular events are both higher in individuals with elevated blood pressure than in those with low 24-hour blood pressure. Especially for individuals under 50 years of age with diastolic blood pressure <16.0 kPa (105 mmHg) who have no prior history of cardiovascular disease, ambulatory blood pressure monitoring is particularly meaningful, as it can guide medication selection and predict the occurrence of cardiovascular events. Many hemodynamic parameters, including systolic blood pressure, diastolic blood pressure, heart rate, and the occurrence of cardiovascular events such as myocardial infarction, sudden cardiac death, and stroke, all exhibit distinct and similar circadian rhythms. For example, during the early morning hours, many of these parameters begin to rise toward their peak values, while the incidence of adverse events is also at its highest during this time. This phenomenon appears to be mediated by neurohumoral factors or the blood coagulation system, which necessitates that any antihypertensive medication used clinically should provide 24-hour blood pressure-lowering protection—especially during the early morning—rather than merely reducing a single spot measurement or the average 24-hour dynamic blood pressure value. Ambulatory blood pressure monitoring also provides an effective means for evaluating the efficacy of non-pharmacological blood pressure-lowering measures. Scherrer et al. demonstrated through ambulatory blood pressure monitoring that weight loss can indeed reduce blood pressure in obese hypertensive patients. Montfans et al. found that behavioral therapies such as relaxation therapy, yoga, and stress management do not lower the 24-hour dynamic blood pressure in hypertensive patients. In summary, with the application of ambulatory blood pressure monitoring, people’s understanding has improved regarding the variability of blood pressure, the impact of environmental stimuli on blood pressure, the ability to distinguish high-risk from low-risk patients among those with similar clinic-measured blood pressure values, and the observation of the effects of antihypertensive treatment, thereby providing new avenues for clinical and epidemiological research on hypertension. However, the technology of ambulatory blood pressure monitoring itself still has numerous limitations; it is not yet a strictly dynamic measurement, there is no unified standard for ambulatory blood pressure values, and the examination cost is relatively high. Therefore, further experience needs to be accumulated before this method can be widely used in clinical practice. Ambulatory blood pressure monitoring has revealed that blood pressure changes regularly over the course of 24 hours. This regular change in blood pressure—the characteristic of circadian rhythm—is that blood pressure rises during the day and falls at night, with some evidence suggesting that higher nighttime blood pressure values are a sign of poor prognosis. (4) White Coat Hypertension Some patients become anxious when they see a doctor; as soon as the doctor indicates that blood pressure is about to be measured, their blood pressure immediately rises, but returns to normal after they leave the doctor's office. This is known as white coat hypertension, meaning that the presence of medical personnel causes a reflexive increase in the patient's blood pressure. Practice has proven that white coat hypertension does indeed exist, and even among individuals who have been taking antihypertensive medications for life, many may not actually have hypertension. Therefore, experts recommend that patients, especially women, undergo 24-hour ambulatory blood pressure monitoring before being diagnosed by a physician and treated as hypertensive patients, in order to prevent misdiagnosis and mistreatment. (5) Pseudo-Hypertension Some elderly patients have very high blood pressure readings when measured indirectly with a conventional sphygmomanometer, but their readings are normal when measured directly. Such “hypertension” is referred to as pseudo-hypertension. Pseudo-hypertension can be confirmed by direct arterial pressure measurement. Although its incidence is not high, it tends to increase with age. Therefore, for hypertensive patients with very stiff peripheral arteries and high blood pressure, if no obvious signs of damage to vital organs such as the brain, heart, or kidneys are found, the possibility of pseudo-hypertension should be considered. Patients with pseudo-hypertension often have arteriosclerosis in the vessels of their organs, leading to insufficient organ perfusion; moreover, their diastolic blood pressure is usually not very high, making them less tolerant of antihypertensive treatment, and they may experience severe complications when taking antihypertensive medications. Therefore, such patients should not undergo aggressive antihypertensive treatment before confirmation. Once diagnosed, treatment should simultaneously address arteriosclerosis and insufficient organ perfusion, eliminate risk factors for arteriosclerosis, reverse arteriosclerosis, and thereby protect the function of vital organs such as the brain, heart, and kidneys. (6) Iatrogenic Hypertension Iatrogenic hypertension refers to hypertension caused by improper medication use by physicians, resulting in blood pressure exceeding normal levels. It is also known as drug-induced hypertension. Although this type of hypertension is not common in clinical practice, understanding it helps differentiate it from primary hypertension and other secondary hypertension caused by various factors.
4. Oral contraceptives: Some women have a potential risk of increased blood pressure after taking oral contraceptives, with an incidence of around 18%. Blood pressure can gradually return to normal after discontinuation of the medication.
5. Monoamine oxidase inhibitors: This class of drugs includes various hydrazine-based antidepressants, such as iproniazid and pargyline.
6. Other drugs: Mainly divided into four categories. The first category comprises drugs with glucocorticoid effects, such as glucocorticoids and licorice; the second category consists of nonsteroidal anti-inflammatory drugs, such as indomethacin; the third category includes hypertension caused by drugs that damage internal organs, such as phenacetin; the fourth category comprises drugs that directly cause vasoconstriction, such as ergotamine, physostigmine, and related alkaloids. Although hypertension caused by the aforementioned drugs is rare in clinical practice, hypertensive patients should use these drugs with caution. When antihypertensive treatment is ineffective, the potential adverse effects of these drugs should also be ruled out. (7) Latent Hypertension Among certain healthy individuals, some do not exhibit any symptoms of hypertension in daily life, but their blood pressure rises above the normal range when subjected to stressors such as fatigue or excitement, which is referred to as latent hypertension. If patients with latent hypertension can be identified early, their onset and progression can be controlled through non-pharmacological therapies. (8) Altitude Hypertension Individuals who live long-term in high-altitude areas often experience elevated blood pressure (particularly diastolic blood pressure), which quickly returns to normal after returning to the plains without undergoing antihypertensive treatment. This is known as altitude hypertension. There are no precise statistics on the overall incidence, but it is significantly higher than the prevalence of hypertension among residents of non-high-altitude areas. Clinically, altitude hypertension mainly manifests as symptoms and signs of general cardiovascular and cerebrovascular diseases, such as palpitations, shortness of breath, cardiac enlargement, arrhythmia, and heart failure, accompanied by elevated blood pressure and sometimes even hypertensive crisis. In treating altitude hypertension, in addition to administering standard cardiotonic, diuretic, vasodilator medications and controlling infection, antihypertensive treatment should also be administered. For those whose long-term active treatment shows little effect or who develop severe organ damage, timely transfer to non-high-altitude areas for treatment is also very important. (9) Sleep-Related Hypertension Among hypertensive patients, there is a special type of hypertension called sleep-related hypertension. This type of hypertension often occurs during sleep or upon waking, with elevated blood pressure. The underlying cause may be related to shallow and slow breathing during sleep, apnea, fluctuations in heart rate, decreased blood oxygen saturation, increased carbon dioxide concentration, and subsequent increased sympathetic activity. It is commonly seen in patients with obstructive sleep apnea syndrome and snorers with sleep apnea. (10) Orthostatic Hypertension Orthostatic hypertension refers to a condition in which a patient's blood pressure rises when standing or sitting, but remains normal when lying down. This type of hypertension accounts for 4.2% of hypertensive patients in China and 10% in foreign countries. A characteristic of this condition is that it generally lacks typical features of hypertension; most cases are discovered during routine physical examinations or by chance, with diastolic blood pressure often being the main component of the elevation, and the fluctuation range being relatively large. In severe cases, patients may experience palpitations, easy fatigue, and difficulty falling asleep. Blood tests show that plasma renin activity is higher than normal, even exceeding that of typical hypertensive patients. The mechanism of orthostatic hypertension is generally believed to be related to excessive filling of the "gravity vascular pool" in veins and venous sinuses. Orthostatic hypertension generally has a good prognosis and does not lead to long-term adverse outcomes, but during diagnosis, it is important to confirm whether it is truly orthostatic hypertension to avoid unnecessary or incorrect treatment measures that could affect the patient's physical and mental health. (11) Refractory Hypertension Treatment for hypertension varies depending on the type, with individualized approaches based on syndrome differentiation. Some cases can be effectively managed with non-pharmacological therapies alone, while others can achieve normal blood pressure with just one common medication. However, there are also several cases where combination therapy fails to control blood pressure, with blood pressure remaining above 20.0/13.3 kPa (150/100 mmHg). This is referred to as refractory hypertension. In fact, there are currently many effective antihypertensive drugs available, so true refractory hypertension is quite rare. Most cases of uncontrolled blood pressure are due to patients not adhering to prescribed medication regimens, failing to limit sodium intake, or taking medications improperly, rather than being truly refractory hypertension. Therefore, careful handling is required in such situations. (12) Blood Pressure Anxiety Disorder Blood pressure anxiety disorder refers to a condition in which patients pay excessive attention to their blood pressure readings, repeatedly measuring their blood pressure multiple times a day without being able to settle down. It is commonly seen in elderly individuals. Japanese scholars have found that with the widespread use of automatic blood pressure monitors in households, people can conveniently measure their own blood pressure at home, but this can sometimes lead to a vicious cycle of anxiety about blood pressure readings, which in turn causes blood pressure to rise. This situation is very similar to white coat hypertension. According to reports, doctors at the Tokyo Geriatric Medical Center in Japan have observed a sudden increase in patients visiting the clinic due to anxiety about rising blood pressure, as many people have recently purchased automatic blood pressure monitors for home use. For example, a 74-year-old woman once discovered during a casual blood pressure measurement that her systolic blood pressure had reached 21.3 kPa (160 mmHg). Her younger family members, concerned about her health, bought her an automatic blood pressure monitor. As a result, she began measuring her blood pressure multiple times a day at home, sometimes more than ten times a day. During these measurements, her systolic blood pressure sometimes reached as high as 25.3 kPa (190 mmHg), causing her to lose sleep at night. She carried her measurement records to various hospitals, seeking treatment, but despite taking antihypertensive medications, her blood pressure did not decrease. Finally, after heeding the doctor's advice that "there is no need to measure blood pressure at home several times a day," her blood pressure gradually stabilized. Chapter 3: Traditional Chinese Medicine Treatment Section 1: Discussions by Past Physicians on Conditions Similar to Hypertension This disease falls under the categories of "headache" and "dizziness" in traditional Chinese medicine. As early as the "Plain Questions" section of the "Inner Canon of the Yellow Emperor," it is recorded: "All wind-related dizziness is attributed to the liver." The "Difficult Questions" states: "True headache originates in the brain." The "Spiritual Pivot" mentions: "When the marrow sea is deficient, the brain spins and the ears ring." The "Classic of the Central Treasury" says: "When liver qi rebels, there is headache, deafness, and red cheeks; the pulse is floating and rapid, the flanks are full, and there is dizziness." The "Classified Treatise on Disease Diagnosis and Treatment" notes: "In old age, kidney essence declines, and water cannot nourish wood." All these indicate that dizziness and headache are closely related to the brain, liver, and kidneys. Zhu Danxi believed that without phlegm there is no dizziness, and without fire there is no vertigo. Li Dongyuan stated: "All headaches are treated with wind-dispelling medicines; broadly speaking, only wind can reach the highest peaks." The "Compendium of Ancient and Modern Medical Systems" says: "Headaches caused from within include wind-cold-phlegm-dampness, stagnation of qi in the five zang organs... Qi-blood-phlegm-stagnation and diseases of the five zang organs are all internal evils." The "Zhang's Medical Compendium" specifically discusses blood stasis-related headaches: when external pathogenic factors invade, blood clots and pulses constrict, small collaterals contract, and pain arises. Ye Tianshi believed that elderly headaches are often caused by the failure of clear yang to ascend, allowing fire qi to take advantage of the void and rise upward. The "Treatise on Blood Disorders" records: "Stagnant blood attacks the heart, causing heart pain and dizziness." All these demonstrate that headaches and dizziness are related to pathogenic factors such as wind, fire, phlegm, and blood stasis. Section 2: Traditional Chinese Medicine's Understanding of the Etiology and Pathogenesis of Hypertension