Childhood hypertension not only exists but is a growing problem and blood pressure control should be included as soon as possible in the protocol of regular pediatric check-ups. This is explained by the specialist in nutritional epidemiology María Dolores Marrodán, director of the Epinut research group at the Complutense University of Madrid, after noting that, in Spain, the percentage of children with high blood pressure has grown by two percentage points over the last decade.
"If in 2013 high blood pressure affected 3.17% of boys and 3.05% of girls of school age, in 2022 it already reached 5.3% of boys and girls between 9 and 16 years old", details Marrodán from the data of investigations in which he has participated.
And she explains that the last of these works – which concluded in the doctoral thesis of María Sánchez Álvarez, which she directed – also shows that hypertension does not affect the entire child population equally, but is concentrated in children with obesity and , especially among those who eat poorly, in those who have a poor quality diet.
“We have seen that the quality of the diet plays a fundamental role, that more than whether they eat a lot or a little or putting children on a diet, what is important is to watch what they eat, because having a low-quality diet doubles the risk of hypertension and alteration in other components of the metabolic syndrome, such as elevated glucose, triglyceride or cholesterol levels”, he says.
Specifically, the study authored by Sánchez, Marrodán and Consuelo Prado found that among the children who followed a quality diet according to the KIDMED index (which measures adherence to the Mediterranean diet) none were hypertensive. Among those with medium dietary quality, the rate was 4.7%. And among schoolchildren with a poor-quality diet, it rose to 8.1%.
In the first investigation, that of 2013, they had already verified that hypertension does not affect all obese children equally, but is concentrated in those who accumulate more abdominal fat, in those in which the ratio between the waist circumference and height is greater than 0.5.
But, emphasizes Marrodán, the increase in the prevalence of childhood hypertension does not only have to do with diet and excess weight. Sleep habits are also decisive. “Not sleeping the necessary hours, which at those ages are between 8 and 10, practically doubles the risk of having high blood pressure or any other component of metabolic syndrome, or both,” he emphasizes.
And he explains that this has to do with the fact that lack of sleep alters hormonal regulation, increases the concentration of cortisol and ghrelin and decreases leptin, and this increases the feeling of hunger and has an impact on stress levels.
Another factor that affects is physical activity. “Doing one hour of intense physical exercise or extracurricular sports three times a week decreases the risk of childhood hypertension by around 20%, so that physical activity, together with a quality diet and sufficient sleep are factors of important prevention," he says.
The epidemiologist stresses that the prevalence that hypertension is reaching among children and adolescents, without being alarming, is beginning to be worrying because there are many studies that associate having high blood pressure in childhood with hypertension, cardiovascular problems, and other associated diseases in adults.
And, despite this, he believes that it is an underdiagnosed problem because measuring blood pressure in children is more complex than in adults. First of all, because there are no single limit values for systolic and diastolic blood pressure (in adults it is 130/80 mmHg), but it depends on the age, sex and height of the child and some tables must be applied to determine whether or not normal values are exceeded.
“But the fact that it is something more complex does not mean that pediatricians and primary care physicians stop assessing blood pressure; It is necessary that its measurement be included in routine pediatric check-ups and that the doctors who care for children know how to take and interpret it”, emphasizes Marrodán.
