The cardiovascular health of children and adolescents around the world is worsening. A scientific study published this Wednesday revealed that childhood hypertension, a key risk factor for the development of cardiovascular and kidney problems, has almost doubled in the last two decades: at the beginning of this century, 3.4% of boys and 3% of girls suffered from this disorder, but in 2020 they were already 6.5% and 5.8% respectively. “It is deeply worrying,” admits Peige Song, researcher at Zhejiang University (China) and author of this study published in the journal The Lancet Child and adolescent health. According to their calculations, today 114 million children under 19 worldwide live with hypertension.
Scientists attribute this increase to worsening lifestyle habits and, above all, to the increase in obesity. The research, which examined up to 83 studies with nearly 444,000 children and adolescents from 21 countries, revealed that the prevalence of hypertension was eight times greater among obese children: 19% of children with excess body fat had high blood pressure, while the prevalence in those with a healthy weight was 2.4%. “The fact that we are identifying these patterns (of hypertension) in increasingly younger populations highlights the urgent need for early detection, prevention and intervention strategies,” warns Song.
Hypertension occurs when blood pressure, or the force exerted by blood against the wall of the arteries as the heart pumps, is too high for a prolonged period. When this happens, the heart is put under excessive strain which, over time, can lead to heart complications, and the arteries can also become stiffer and narrower, causing insufficient blood flow, or rupture and cause bleeding.
In reality, it is a risk factor traditionally associated with adulthood, but its increasingly frequent appearance at such an early age has alerted the scientific community: “Numerous studies have shown that childhood hypertension, if untreated, can persist into adulthood and significantly increase the risk of cardiovascular complications in later life,” warns Song. High blood pressure in adults, if not controlled with medications or lifestyle changes, can cause heart and cerebrovascular problems, such as heart attacks and strokes, and even kidney failure.
In practice, what the upward trend in childhood hypertension data reflects, the scientist argues, is “a deterioration in cardiovascular health at a younger age.” And he attributes much of this phenomenon to “factors linked to the modern lifestyle, such as diets rich in salt and ultra-processed foods, increasingly sedentary habits and, above all, the marked increase in childhood obesity”. The researcher points out that these behaviors not only increase blood pressure, but also “accelerate metabolic and vascular changes that can lead to serious cardiovascular problems in adulthood.”
The footprint of obesity
It is not the first time that the scientific community has drawn attention to the impact that unhealthy lifestyle habits and, above all, childhood obesity can have, in the short, medium and long term, on the health of children. An example is the appearance of adult diseases, such as hypertension, at increasingly younger ages. But experts also warn that it is especially excess body fat that leaves a mechanical, metabolic and psychological imprint that can perpetuate lifelong health problems.
Ignacio Fernández Lozano, president of the Spanish Society of Cardiology, assures that research like this, in which he did not participate, helps to illustrate trends and shows with data what specialists have been perceiving for some time during the consultation: “It is worrying because we see that the cardiovascular health of children and adolescents is worsening. Hypertension is an adult disease and that it begins to manifest itself at such an early age is alarming”, he complains.
This early cardiovascular risk, explains Pedro Arango, pediatric nephrologist at the Sant Joan de Déu hospital in Barcelona, has already begun to translate into “signs of organ damage”. “In pediatrics we are increasingly seeing damage to the retina or ventricular hypertrophy of the heart linked to hypertension,” he explains.
The “good news” in this area, Song notes, is that hypertension in children is modifiable. “With early diagnosis, better nutrition, increased physical activity and policies that encourage healthier environments, there is a real opportunity for prevention,” he agrees. And it also calls for diagnostic strategies for childhood hypertension to be improved and made more flexible to improve early diagnosis.
Hypertension disguised as a white coat
This call to refine diagnostic methods is not trivial. The meta-analysis demonstrated that estimates of the prevalence of childhood and adolescent hypertension depend, to a large extent, on blood pressure measurement methods. That is, the data varies depending on whether the data is collected from repeated measurements in the office or externally (for example via blood pressure monitors at home).
How and where it is measured, in fact, reveals phenomena such as masked hypertension – which can only be diagnosed when measurements are included outside the consultation – or white coat hypertension, which occurs when high blood pressure is identified when measured in the health center, but not outside this healthcare environment. The meta-analysis identified that the former affects 9.2% of children and adolescents worldwide and the prevalence of the latter is 5.2%. “Both conditions illustrate the complexity that measuring blood pressure in children can involve,” Song assumes.
Masked hypertension, in which a child’s blood pressure appears normal in the office but is elevated outside of it, can lead to “underdiagnosis, as these children may be told they are fine when they are not,” explains the researcher. But on the other hand, white coat hypertension, which only manifests itself punctually during the visit and not outside of it, can also “generate unnecessary worries or even excessive treatment,” he admits. “These findings highlight the limitations of isolated in-office measurements and the importance of off-site monitoring, especially for children with borderline (between normal and pathological) blood pressure.”
Another phenomenon studied in the meta-analysis is prehypertension, defined as blood pressure that is higher than normal but does not reach the hypertensive range. “It’s an important warning sign,” Song sums up. Research confirms that approximately 8.2% of children under 19 fall into this category, although it is more frequent among adolescents: in these age groups it rises to 12%, compared to 7% in younger children. “(Adolescence) is a crucial time for surgery and an opportunity to prevent long-term complications,” Song says.
