For decades, arterial hypertension was regarded as a typical disease of adulthood, strictly related with aging and associated with clinically evident other diseases such as diabetes, ischemic heart disease and/or chronic kidney disease. However, the first measurements of blood pressure in hospitalized children started already 100 years ago when Cook and Briggs from John Hopkins Hospital reported that hospitalized children aged up to 2 years had systolic blood pressure in range from 75 to 90 mmHg and preschool children had systolic blood pressure in the range from 90-110 mmHg. In next decades when strict relations between blood pressure values and cardiovascular risk was documented, blood pressure measurements became routine clinical practice in adults. It is important to note that this analysis was ordered by insurance company Kaiser Permanente and was published in 1925 (1). In Poland, Aleksander Januszkiewicz from Vilnius University stated already in 1922 that “sphygmomanometric measurement of blood pressure” should be routine clinical practice. He also published results of first population study of blood pressure measurements in young adults and adolescents in Poland made in 1920s in Vilnius by Zajączkowski and Łobza (2, 3). They measured blood pressure in 2700 army recruits and 303 male, “non-army” adolescents in age 16-20 years. Blood pressure was measured several times using Korotkov sphygmomanometer, in lying position, at least 1-2 hours after physical exercise. According to Januszkiewicz report, normal systolic blood pressure was in the range of 101-130 mmHg. Systolic blood pressure above 140 mmHg was noted in 10.5% of recruits and in 6.6% of non-army adolescents.

In the same time i.e. in years 1928-1932, normative values of blood pressure in adolescents and adults were published in United States. It was found that systolic blood pressure values rise with age and until age of 30 years are higher in males than in females. In 1924 Stocks published normative values of blood pressure including children below 10 years of age. He reported blood pressure values in age strata from 5 to 39 years in two-year intervals (4). Interestingly, these values are similar to normative values used nowadays. Stocks made few interesting observations and noted that systolic blood pressure rises from adolescence until 39^th year of age and that diastolic blood pressure is relatively stable. Thus, it leads to increase of pulse pressure. In Poland, the first pediatric report on blood pressure is from 1925 when Matylda Biehler in her handbook “Principles of diagnosis of pediatric diseases” cited results of the study by dr Nobècourt, who measured blood pressure in children with Riva-Rocci method (5). In the same handbook she also noted that in children in age below 4 years “blood pressure is difficult to estimate, is elevated during crying and lowered during sleep”. Biehler proposed also an algorithm to calculate blood pressure in relations to age: blood pressure = 80 + (2 x X); where X is the age in years.

The next step in understanding character of blood pressure distribution in pediatric population is from reports published in 1952 by Hamilton et al. They published referential values of blood pressure based on measurements done in patients, including children from 10 years of age, who were referred to departments of dermatology, orthopedics and because of venous atheroembolic disease (6). Although blood pressure measured in hospitalized patients cannot be regarded as source data for construction of normative referential values, this study gave few important results. First, they found that in every age strata, including children, blood pressure values have normal distribution and there is no strictly defined threshold dividing normal and abnormal blood pressure values. Second, it indicates that those subjects who have highest blood pressure will suffer in future from hypertensive disease. However, those who have normal blood pressure will have normal blood pressure in future or risk of increase of blood pressure will be lower. Third, Hamilton et al. made in 180 subjects second blood pressure measurements after 3 weeks to 4 months. They found that mean blood pressure values were significantly lower than those obtained during first measurement and the difference was higher the higher was first blood pressure measurement. These historical reports which evidence normal distribution of blood pressure in population gave arguments for advocates of polygenic etiology of arterial hypertension in discussion with advocates of monogenic origin of arterial hypertension.

In the next decade first reports of normative blood pressure values expressed as percentile charts were published. In 1966 Londe published normative values of blood pressure based on measurements done in 1473 healthy children and adolescents in age range 4-15 years and presented values of 80^th and 90^th percentile for systolic and diastolic blood pressure (7). In the same time, in Poland Mira Pyżuk and Napoleon Wolański published percentile charts of systolic and diastolic blood pressure for children and adolescents in age from 3 to 18 years (8, 9). However, the percentile charts were combined both for girls and boys because, as authors claimed “the differences between blood pressure values in boys and girls were statistically negligible”.

The important step in description of the pediatric hypertension was done in 1970s when the first report of the US Task Force for Blood Pressure in Children and Adolescents was published. In this publication known as “The First Report”, pediatric blood pressure normative values based on data obtained in population studies were published and definition of arterial hypertension in childhood based on percentile distribution and cut-off of 95^th percentile was proposed. Because of white coat effect, it was proposed to define arterial hypertension when elevated blood pressure was found on three independent measurements. Since then, the next Task Force Reports were published in 10 years intervals. The last, the 4^th Task Report was published in 2004 (10). Task Force Reports include both normative blood pressure values and guidelines for the diagnosis and management of blood pressure in children and adolescents. The normative values of blood pressure presented in the Task Force Reports are based on results obtained in NHANES studies. The next, 5^th Task Report is prepared to be published in 2016.

Normative values of blood pressure based on sphygmomanometric auscultatory measurements published in the Task Force Reports became the most often used referential data. In 2009 European Society of Hypertension published pediatric guidelines of diagnosis and management of hypertension in children and adolescents and now new, updated European guidelines are prepared to be published in 2016 (11).