High blood pressure is the second main modifiable risk factor for dementia. Despite this, almost 7 in 10 (66%) Brazilians diagnosed with high blood pressure do not control the disease.
The warning about the lack of adequate treatment for the chronic disease and its consequences was addressed last month in the capital of São Paulo at the 1st Big Data Abraz — the acronym refers to the Brazilian Alzheimer’s Association.
At the time, an estimate was released that the country has 1.7 million people aged 60 or over with some type of dementia — equivalent to 6% of the population in this age group. Alzheimer’s alone accounts for 55% of these cases (966,594).
Other data presented indicated the risk of hypertension and, above all, the lack of control of the condition.
In total, it is estimated that 38 million adults have high blood pressure — about a quarter of the population over 18 years old. Considering the condition alone, without taking into account whether it is being controlled or not, it is projected to increase the death rate from dementia by 72% in ten years.
Furthermore, the condition can increase the risk of developing dementia by up to 45%, in the age group of 50 to 75 years, according to research published at the end of 2022 and whose data were also discussed at the event in São Paulo. Among the authors of the work is the professor of geriatrics at FMUSP (USP Faculty of Medicine) Claudia Suemoto.
This study also points out that 48% of dementia cases in the country are attributed to modifiable factors, that is, they are not genetic and can be altered, for example, by changing lifestyle habits. The first of them is education (7.7% prevalence) and the second is high blood pressure (7.6%).
Changing these factors, according to research, can reduce cases of dementia in poor places by up to 54%.
However, 25 million hypertensive patients, the majority of the population, do not follow medical instructions to keep the condition under control.
“Even in younger individuals who undergo early diagnosis and control, high blood pressure increases the risk of dementia”, says cardiologist Erika Campana, associate professor at the Department of Chest Diseases at Uerj (State University of Rio de Janeiro) and specialist at the SBC (Brazilian Society of Cardiology).
“And, unfortunately, we only have a third of hypertensive patients under control. Often, when a late diagnosis is made, it is no longer possible to stop the process.”
For Campana, the asymptomatic nature of hypertension is the main barrier to control. “It is very important, because it leads to the perception that nothing is happening, mainly because the most serious symptoms can appear in a medium to long term period.”
According to Polyana Piza, neurologist and coordinator of the Clinical Specialties Program at Hospital Israelita Albert Einstein, there is a correlation between neurodegenerative diseases and chronic diseases, such as hypertension. “We see in chronic hypertensive patients the cognitive changes typical of vascular dementia or Alzheimer’s earlier than would be expected, that is, hypertension is a risk factor for dementia and is also a stressor, it worsens the neurodegenerative condition.”
Therefore, it is important to map the prevalence of hypertension as soon as possible, even in younger people, to avoid this possible cognitive decline in the future. “At first, high blood pressure does not usually present classic symptoms, which can be a determining factor for people to seek help,” she says.
This was the case of real estate agent Francisco Nóbrega. He was just 43 years old when he suffered a heart attack in June last year. The day before, he had spent the day at sea surfing, his favorite sport. Upon arriving at the hospital, his blood pressure was 240 to 140 mmHg (considered well above normal, 120 to 80).
“Before that, I didn’t have any health problems. I went to the hospital once with high blood pressure [140 por 100 mmHg], but the doctors said I had abused it over the weekend, ate a lot of barbecue, drank beer. But after you suffer [o infarto]he sees life with new eyes”, he says. In his family, his parents were hypertensive and an uncle and grandfather also suffered heart attacks at a young age, aged between 45 and 55.
Piza, from Einstein, states that recently several studies have sought to better understand the causes that lead to the association of hypertension with neurological risk. According to her, there is a barrier called blood-brain, which acts as a “filter” for substances that enter the brain via the bloodstream.
“This protection exists because the brain is very vulnerable to toxins. Substances that are toxic to the body at a much lower level are already harmful to the central nervous system [que inclui o encéfalo e a medula espinhal]. Therefore, this barrier exists”, he states. “In chronic hypertensive individuals, however, this barrier is broken, due to blood pressure, damaging the cells of the nervous system early and leading to cognitive loss.”
Another way in which high blood pressure accelerates cognitive decline is its association with cardiovascular diseases, especially strokes. According to the neurologist, there is a difference between dementia of neurodegenerative origin, which includes Alzheimer’s, and vascular dementia.
“Vascular dementia originates from small ischemic strokes [quando há obstrução de uma artéria cerebral] which, in a diffuse amount, end up interfering with cognition. And, in patients who have vascular changes, even without having suffered a stroke, but with changes in the vessel wall, we call it leukoaraiosis, or white matter disease, which, in large quantities, also leads to significant cognitive changes”, he explains. .
The increased prevalence of some other risk factors, such as obesity and diabetes, especially in young people and women, is also a concern. “Strokes themselves are related to lifestyle habits. Diabetes, blood pressure, obesity, high cholesterol, they go together. So it is necessary to think about re-education in terms of lifestyle”, says Piza.
According to experts, these factors can be avoided by controlling hypertension through medication and monitoring.
“Thinking about the context of the treatment itself, our biggest bottleneck is convincing the patient that they have to undergo continuous treatment, daily monitoring and changing lifestyle habits”, assesses Campana.
The main reason for patients not adhering to treatment, according to a recent study presented at the European Congress of Cardiology, on August 25th to 28th in Amsterdam, was forgetfulness, reports Campana. The second, not feeling anything. “It is important to observe these results because many of the patients, when asked why they didn’t tell the doctor about their forgetfulness, responded that they didn’t want to bother the doctor, or were afraid of being scolded”, reports the doctor.
Nóbrega monitors his blood pressure every day, in addition to taking medication to control it. According to him, it is important not to forget to take exams regularly to detect any changes early. “Hypertension, it’s silent, it doesn’t give you a warning beforehand. And it’s something that when it comes, it’s all at once.”