The National Hypertension Education Program (NHBPEP) reports that in children and adolescents, hypertension is defined as blood pressure between the 90th and 95th percentile in childhood as “prehypertension” when the systolic and/or diastolic blood pressure measurements are ≥95th percentile on multiple measurements. In adolescents, a blood pressure of ≥120/80 mmHg must be considered prehypertensive. In general, the diagnosis is made when the blood pressure is greater than 90/60 mmHg in newborns, 100/60 mmHg in infants, 110/70 mmHg in preschoolers, and 110/80 mmHg in school-age children, and has been repeatedly confirmed. The diagnosis of hypertension in children should be more careful and cautious compared to adults. First, the growth rate of each child varies, so the height and gender of the child should be taken into account along with the age factor. A tall child may have normal blood pressure even if it is slightly higher than the same age group; conversely, a short child may have hypertension even though his or her blood pressure is still normal for the same age group. In addition, there are subtle gender differences in blood pressure. Second, children’s blood pressure is more susceptible to psychological factors. Many children are nervous and scared when they see a doctor, and some may even cry, all of which can lead to high blood pressure values in the side, which is known as “white coat hypertension. To reduce this phenomenon, measurements should be taken several times (usually more than three times) at different times, and children should be kept as relaxed as possible and the measurement environment should be kept quiet. Finally, blood pressure measurement in children should be done by a medical professional, using a stethoscope with a cuff. Various blood pressure measuring devices suitable for adults are very easy to use, but they have a large error for children and are not recommended at this time. Why should I pay attention to hypertension in children? Like hypertension in adults, hypertension in children is divided into two categories: primary hypertension and secondary hypertension. The former refers to a category of hypertension where the cause is not yet clear. The latter, as the name implies, refers to hypertension that is secondary to disease factors. Primary hypertension accounts for the majority of adults but is relatively uncommon in children. 80% of children under 10 years of age have secondary hypertension. In older adolescents with hypertension, the proportion of primary hypertension is higher. Primary hypertension in children may be asymptomatic or mild, so it is difficult to detect, or it may be detected on physical examination but usually does not attract parental attention. In fact, mild childhood hypertension, although it may not significantly affect the affected child for quite some time, is slowly damaging various organs of the body, such as blood vessels, heart, kidneys and brain. A growing body of research now concludes that primary hypertension in children, if left untreated, can contribute to a large extent to the development of hypertensive disease in adulthood. In addition, such children are significantly more likely to develop coronary artery disease, often referred to as “coronary artery disease,” in the future. Secondary hypertension in children is a sign of an underlying disease. These include kidney disease, cardiovascular disease, endocrine disease, and lead poisoning. For example, glomerulonephritis, pyelonephritis, nephrotic syndrome, renal artery stenosis, aortitis, aortic constriction, pheochromocytoma, primary aldosteronism, and lead poisoning may be the “culprits” of hypertension. Therefore, if this type of hypertension is not given sufficient attention, the diagnosis and treatment of the primary disease may be delayed, resulting in adverse consequences. Which children are at risk for hypertension? As mentioned above, secondary hypertension is caused by the primary disease and can be clinically diagnosed as primary hypertension if the primary disease is ruled out one by one. Primary hypertension is influenced by many factors, mainly genetics, obesity and lifestyle and mental status. Generally speaking, if one of the parents has primary hypertension, the chances of the child having hypertension increase. Some data show that more than 50% of children with primary hypertension have a relevant family history. In addition, obesity is also an important cause of hypertension. According to studies, obese children are nearly nine times more likely to develop hypertension than normal children! Some statistics show that the average blood pressure of children in the United States has increased over the last decade, in large part due to the increased percentage of obese and overweight children. In addition, lifestyle is an important influencing factor. Poor dietary habits such as high salt and low potassium, high fat and high sugar, and chronic lack of physical activity can all contribute to high blood pressure. Mental status is also very influential on blood pressure in children, which involves social factors. Family discord, excessive academic tasks, and prolonged game playing can cause emotional stress in children. The brain and central nervous system of children are in a period of imperfect development and are easily excited and fatigued. When subjected to adverse stimuli, the brain excitation and inhibition dysregulation, through a series of feedback pathways thus leading to an increase in blood pressure. Foreign studies have been done on the effect of playing games on blood pressure. They followed up 1400 students in two nearby schools and compared the blood pressure information before and after the video games, and found that the proportion of nervous hypertension was higher in children who often played video games than in other children. Children also had a much greater increase in blood pressure when playing video games. How should hypertension in children be prevented and treated? The main symptoms of hypertension in children are dizziness, headache, nausea, and blurred vision, which may manifest as convulsions in severe cases. Children with secondary hypertension may also show symptoms of pre-existing diseases, such as swelling and hematuria in the case of acute glomerulonephritis. Prof. Sun said that if children occasionally complain of similar symptoms, parents may want to take them to the hospital for a checkup, especially for the aforementioned susceptible children, which should be brought to the attention of parents. Generally speaking, the problem of secondary hypertension will be solved when the primary disease is relieved. Primary hypertension, on the other hand, should be addressed primarily from both a lifestyle and a psychiatric perspective. The first aspect of lifestyle, especially for the aforementioned children who are susceptible to hypertension, is dietary control. This includes avoiding a salty diet to reduce salt intake, appropriately limiting “three high” foods (high sugar, high fat, high protein), supplementing with foods rich in potassium (such as bananas) and eating more vegetables and fruits. The daily salt intake recommended by the United Nations World Health Organization is 6g, which is about the amount of a toothpaste cap. Clinical practice also shows that limiting salt intake is an important non-pharmacological treatment for hypertension in children. Second, strengthen physical exercise and encourage children to exercise more. Exercise can not only consume excessive heat in the body, but also increase lung capacity, enhance cardiopulmonary function and myocardial fiber contraction, which is beneficial to the physical and mental development of children. These methods are also beneficial for obese children to reduce their weight and control their blood pressure while helping them to control their weight. In terms of mental regulation, first of all, we should avoid giving children excessive mental stress. Family education should be loose rather than tight, and children should be given appropriate free space. Secondly, for children who love to play video games, they should strictly control the game time and never indulge. Again, creating a warm and quiet living environment is also conducive to children’s emotional stability. For some severe hypertension or hypertension that is difficult to control by the above-mentioned regulation methods, it should be controlled with antihypertensive drugs under the guidance of a doctor. In conclusion, the scientific attitude towards children’s hypertension should be “pick up heavily and put down gently”. In other words, parents should be vigilant and pay enough attention to it, while medical professionals should examine it carefully and diagnose it cautiously. However, in terms of prevention and treatment, prevention is the main focus, supplemented by treatment; and in terms of treatment, diet control is the main focus, supplemented by drug treatment. Finally, it is hoped that by raising awareness of hypertension in children, the whole society can care for children’s health in a more subtle and comprehensive way!