Hypertension (hypertension) is a clinical syndrome characterized by increased arterial blood pressure (systolic and/or diastolic) in the body circulation (systolic blood pressure ≥ 140 mm Hg and diastolic blood pressure ≥ 90 mm Hg), which may be accompanied by functional or organic damage to the heart, brain, kidneys and other organs. Hypertension is the most common chronic disease and the most important risk factor for cardiovascular and cerebrovascular diseases. Blood pressure in normal individuals fluctuates within a certain range in response to changes in the internal and external environment. In the overall population, blood pressure levels rise gradually with age, more markedly with systolic blood pressure, but after age 50 diastolic blood pressure shows a decreasing trend and pulse pressure increases. Blood pressure should be measured using standard measurement methods and validated instruments (including in-office blood pressure measurement, automated in-office blood pressure measurement, home self-measurement, and ambulatory blood pressure monitoring). Four methods of measuring blood pressure: 1. Office blood pressure measurement: Upper arm blood pressure measurement device electronic blood pressure (oscillometric sphygmomanometer) is superior to the auscultatory sphygmomanometer (Class C). When the average office blood pressure of systolic blood pressure ≥ 140 mmHg or diastolic blood pressure ≥ 90 mmHg is high, when the systolic blood pressure in 130-139 mmHg and/or diastolic blood pressure in 85-89 mmHg is normal high value (Class C). 2.Automated office blood pressure monitoring: When using automated office blood pressure monitoring, the threshold of elevated blood pressure is systolic blood pressure ≥ 135 mmHg or diastolic blood pressure ≥ 85 mmHg (grade D). 3, ambulatory blood pressure monitoring: ambulatory blood pressure monitoring, when the patient is awake, the average blood pressure ≥ 135mmHg or diastolic blood pressure ≥ 85mmHg or if the 24-hour average blood pressure ≥ 130mmHg or diastolic blood pressure ≥ 80mmHg, is hypertension (grade C). 4, home self-measurement of blood pressure: average systolic blood pressure ≥ 135mmHg or diastolic blood pressure ≥ 85mmHg can be diagnosed as hypertension (Class C). However, if the office blood pressure is elevated and the home self-measured blood pressure is <135/85 mmHg, before making the diagnosis of white coat hypertension, it is recommended to repeat home blood pressure monitoring to determine the home blood pressure <135/85 mmHg; or perform 24-hour ambulatory blood pressure monitoring to determine the average blood pressure <130/80 mmHg and the average ambulatory blood pressure <135/85 mmHg when awake.