It’s rare a ray of hope: recent studies show that the rate of new cases of Alzheimer’s disease tends to be stable or decreasing in Western Europe and the United States. The likely cause: the improvements in the standard of living (eating, physical activity) of the people living in these areas that reduce both cardiovascular risk and dementia.
Over a hundred years after the identification of Alzheimer’s disease, there is still no treatment that can cure or effectively alter the course of the neuro-degenerative disease. But it’s not all bad news. Indeed, while 7.7 million new cases of dementia are reported each year — one every four seconds — a stabilizing trend has appeared in rich countries when it comes to Alzheimer’s disease, according to all recent studies in Sweden, Spain, the Netherlands, the UK and the US.
The decline in the incidence (rate of new cases) of Alzheimer’s disease and related dementia in people over 65 years is “a trend,” says Professor Philippe Amouyel, epidemiologist at the CHU Pasteur Institute in Lille, France. However, he says, that the total number of cases will continue to rise as humans live increasingly longer due to longer life expectancy. “We have stemmed the flow, but without stopping it completely,” says David Reynolds of the British Association Alzheimer’s Research UK (ARUK). He nonetheless believes that the economic and social burden of dementia is not going to decrease. The annual global cost of dementia has already reached 818 billion dollars, according to the 2015 report of the experts of Alzheimer’s Disease International, an organization funded in 1984 to fight Alzheimer’s disease.
Alzheimer’s disease, age-related and the most common cause of dementia, would be responsible for 60-70% of cases. Vascular dementia is the second cause. However, the association of these two diseases is common, according to experts. The causes of the disease involving abnormal proteins in the brain are still being debated. Recently, pollution was mentioned.
On its own, the United Kingdom has seen a 20% drop in the overall incidence rate of dementia for over two decades. According to a study published in April in the journal Nature Communications, the country had 209,000 new cases in 2015, well below the 251,000 envisaged in the 1991 forecast.
Among the hypotheses that could explain this decline: an improvement in living standards and education, and cardiovascular risk reduction, including better management of hypertension and high cholesterol. “Anything that helps to reduce cardiovascular risk seems beneficial, such as physical activity, healthy eating, abstinence from smoking,” says Professor Amouyel.
Moreover, according to some studies, everything that makes the brain work such as higher education or activities ranging from crosswords or sudoku, reading or DIY activities helps reduce the risk of dementia, he adds. Meanwhile, other factors may yet reverse the trend in the wrong direction like the progression of diabetes, obesity and physical inactivity, warn the experts.