This is good news for public health. While Alzheimer’s disease and other dementia affect 50 million people worldwide, and that figure could triple by 2030, a new study shows that adopting a healthy lifestyle, which protects against cardio Vascular, also helps preserve the health of the brain.
The work coordinated by the EpiAgeing team of the epidemiology and statistics research center of the National Institute of Health and Medical Research (Inserm) is published Thursday, August 8 in the British Medical Journal . They conclude that 50-year-olds who adhere to Life’s Simple 7 recommendations (a cardiovascular health score built from seven parameters) subsequently develop fewer dementias. For each point gained on this score from 0 to 14, the risk of brain damage decreases by 11%. Clearly, even small improvements in lifestyle are paying off.
Adopted by the American Heart Association (AHA) in 2010, Life’s Simple 7 has four behavioral parameters (smoking, diet, physical activity and body mass index) and three biological parameters (fasting blood glucose, total cholesterol and blood pressure), identified as the most important for the health of the heart and arteries.
Each being rated 0 (level at risk), 1 (intermediate level) or 2 (optimal level), the tool allows to calculate a score from 0 to 14, reflecting the level of protection against cardiovascular diseases – mainly myocardial infarction and cerebrovascular accidents. The Life’s Simple 7 is available free on the AHA website, about 100 000 people have created a profile.
According to these criteria, optimal cardiovascular health (maximum score) corresponds to an individual who has never smoked or stopped for more than one year, with a normal weight (body mass index less than 25 kg / m 2 ), a varied and healthy diet, and physical activity in line with World Health Organization recommendations (more than 150 minutes per week of moderate intensity activity or 75 minutes of sustained intensity).
Biologically, total cholesterol is less than 200 milligrams per deciliter (mg / dl), fasting glucose level is below 100 mg / dl and normal blood pressure – less than 120/80 mm mercury (mmHg).
To evaluate whether this score is as predictive of the risk of Alzheimer’s disease and other dementias, Séverine Sabia, researcher at Inserm and the University College of London, and her colleagues have calculated – with slightly modified for the purpose of the study – at nearly 7,900 British officials in the Whitehall cohort at the age of 50. With an average follow-up of twenty-five years, 347 cases of dementia were recorded.Read also Alzheimer’s: 1 million patients, 2 million caregivers, 20 billion euros in costs … and 0 treatment
Compared to the group with a low level of cardiovascular health (score from 0 to 6), individuals with an intermediate level (score of 7 to 11) and those with an optimal level (12 to 14) had a level of risk decreased by 39% and 43%, respectively.
This neuroprotective effect was found in people who developed cardiovascular disease, but also in those who remained free from cardiovascular events. “Our results suggest that at age 50, the seven Life’s Simple 7 parameters synergistically contribute to the protection against Alzheimer’s disease and other dementias. The risk reduction is evident from an intermediate level of the score, “ says Séverine Sabia.
“Never too late to get started”
In August 2018, Cécilia Samieri’s team (Inserm, Bordeaux Population Health Research Center) published in the Journal of the American Medical Association a similar study based on the French cohort of the Three Cities, launched in 2000, which includes 10,000 people aged 65 and over. The Life’s Simple 7 score was measured at the age of 65, and was predictive of dementia risk with a follow-up of 15 years. “We had obtained the same amplitude of results with a risk reduction of 10% per additional point to the score, but the strength of this new study is to have applied these parameters earlier, at 50 years,” said Cecilia Samieri.
For the researcher from Bordeaux, these results are in line with current conceptions of Alzheimer’s disease, with risk factors that accumulate throughout life and are particularly important from the forties.
“Dementia and cardiovascular diseases are environmental pathologies with common determinants. With a perfect lifestyle, 80% would be preventable, but this study shows that it’s never too late to get started , “said Professor Claire Mounier-Vehier (Heart Institute Lung, CHU Lille), who did not participate in this work. The cardiologist, outgoing president of the French Federation of Cardiology, also notes that “even a moderate observance is effective, which can reconcile the concept of prevention and pleasure . “
Should we already translate Life’s Simple 7 and offer it to the population, to encourage the French to improve their lifestyle and thus lower their risk of heart disease or dementia?
“One of the strengths of this tool is to deliver a positive message, encouraging the accumulation of good attitudes rather than scare the risks ,” continues Cecilia Samieri. But for now, it’s more for research than for mainstream use. “ With regard to food and physical activity, the criteria are difficult to evaluate themselves objectively, she said, and would probably fit. “In cardiology, doctors are working on different tools to stratify risks as finely as possible, but we must also model scores accessible to the general public,” said Claire Mounier-Vehier.
“The Life’s Simple 7 test is part of the current movement, which seeks to take into account the overall health risks, even if it is less precise on certain items, the quantification of LDL cholesterol [” bad cholesterol “] for example “ Says Thierry Couffinhal, professor of cardiology and director of a research unit Inserm (Bordeaux), who will soon test this score among patients in his department.
Beyond primary prevention, the aim of which is to prevent illnesses by reducing existing risk factors, and secondarily, to prevent recurrence of accidents, a prevention strategy, which is more fundamental and upstream, is emerging. “It’s a population-based approach, which aims to prevent the appearance of risk factors, for example by promoting physical activity, banning smoking in public places, reducing the salt content food, “ says Claire Mounier-Vehier. A more behavioral, less medicated conception of health. A whole revolution.