We often hear people around us say “high blood pressure”, but how high is blood pressure really considered “high blood pressure”?
In fact, there is a clinical standard.
The human blood pressure is a continuous normal distribution, the normal human blood pressure is: systolic blood pressure <120mmHg and diastolic blood pressure <80mmHg. when the systolic blood pressure ≥120~139mmHg and (or) diastolic blood pressure 80~89mmHg, then the normal high blood pressure.
In contrast, the current definition of hypertension in China is: systolic blood pressure ≥ 140 mmHg and/or diastolic blood pressure ≥ 90 mmHg on three non-same-day office measurements without the use of antihypertensive drugs.
Blood pressure measurement chart for patients with hypertension
Depending on the level of elevated blood pressure, it was further divided into grade 1, grade 2 and grade 3.
Grade 1 hypertension: i.e., mild hypertension with a systolic blood pressure of 140 to 159 mmHg and/or a diastolic blood pressure of 90 to 99 mmHg.
Grade 2 hypertension: i.e., moderate hypertension with a systolic blood pressure of 160 to 179 mmHg and/or a diastolic blood pressure of 100 to 109 mmHg.
Grade 3 hypertension: i.e. severe hypertension with systolic blood pressure ≥ 180 mmHg and/or diastolic blood pressure ≥ 110 mmHg.
The same hypertension, why some will be inherited and some will not, and even cured?
That is because, depending on the cause of hypertension, hypertension is divided into primary hypertension and secondary hypertension.
Primary hypertension, also known as “hypertension”, accounts for more than 90% of all hypertension and is the most important risk factor for cardiovascular disease.
It often coexists with other cardiovascular risk factors and can damage the structure and function of important organs, such as the heart, brain, and kidneys, eventually leading to the failure of these organs.
As for the cause of the emergence of primary hypertension, there are several factors, mostly the result of the interaction of genetic and environmental factors, but it is not clear exactly through which pathway genetic and environmental factors raise hypertension.
Diagram of heart damage due to hypertension
Secondary hypertension, also known as “symptomatic hypertension,” is an increase in blood pressure caused by some defined disease or cause and accounts for about 5% of all hypertension.
Although this type of hypertension does not account for a high percentage of cases, the absolute number is still relatively high.
When the primary disease is cured, the blood pressure will follow or return to normal.
For example, primary aldosteronism, pheochromocytoma, renal vascular hypertension, and renin-secreting tumors can be cured or improved by surgery, and the symptoms of “high blood pressure” that were previously present in people with these diseases will come down after the disease is cured.
What are the epidemiological characteristics of hypertension?
At present, about one in four adults in China has hypertension, and the total number of people with hypertension is as high as 244 million.
In terms of the epidemiological distribution of hypertension prevalence, the most striking features are the age and regional differences.
First, the prevalence of hypertension tends to increase significantly with age.
According to the national survey from 2012 to 2015, the prevalence of hypertension in the ages of 18 to 24, 25 to 34, and 35 to 44 was 4.0%, 6.1%, and 15.0%, respectively, and 35 to 44 was the age group with the fastest increasing prevalence of hypertension; and the number of people with hypertension in the age group of 65 to 74 had exceeded 50%.
Second, the phenomenon of high in the north and low in the south still exists, but the difference is now changing, showing a higher prevalence of hypertension in large and medium-sized cities, such as 35.9%, 34.5% and 29.1% of residents in Beijing, Tianjin and Shanghai, respectively.
The prevalence of hypertension among residents in rural areas increased faster than in urban areas, and the results of the 2012-2015 national survey showed that the prevalence in rural areas (crude rate 28.8%, standardized rate 23.4%) surpassed that in urban areas (crude rate 26.9%, standardized rate 23.1%) for the first time.
In addition, the prevalence of hypertension varied among different ethnic groups, with Tibetans, Manchus and Mongolians having a higher prevalence of hypertension than the Han Chinese population, while Hui, Miao, Zhuang and Buyi all had a lower prevalence of hypertension than the Han Chinese population.
References
[1]Guidelines for the prevention and treatment of hypertension in China (2018 revised edition) [J]. Chinese Journal of Cardiovascular,2019,24(1):24-56.
[2]Zhao Dong. Current epidemiology of hypertension in Chinese adults[J]. Chinese Journal of Cardiovascular,2020,25(06):513-515.
[3]Ge Junbo,Xu Yongjian,Wang Chen. Internal Medicine. 9th edition [M]. Beijing. People’s Health Publishing House.2018.247-250.