Cerebrovascular accident (CVA), after-effects of Covid, Alzheimer’s… According to a large study published this Friday March 15, in The Lancet Neurology, pathologies that strike the nervous system have become the main cause of health problems worldwide. In 2021, 3.4 billion people – or 43% of the world’s population – were affected by a neurological disorder, according to research carried out by hundreds of scientists under the aegis of the Institute for Health Metrics and Evaluation (IHME), the reference organization for health statistics.
This type of condition thus overtakes cardiovascular pathologies – such as myocardial infarction or heart failure – which nevertheless remain the leading cause of mortality in the world, according to the World Health Organization (WTO), with 19.8 million deaths compared to 11 million for neurological pathologies.
In total, these are responsible for the loss of 443 million years of healthy life – an indicator intended to go beyond simple life expectancy, calculating the period during which a person can live without being limited in activities of daily life – of the entire world population. By comparison, in 1990, researchers estimated that neurological conditions accounted for the loss of 375 million years of healthy life. This figure has therefore jumped by 18% in 31 years.
Strokes at the top of neurological conditions
At the top of the list are strokes, by far. These have caused the loss of 160 million years of healthy life. This is followed by neonatal encephalopathy – a form of pathology which affects a child from birth -, Alzheimer’s type dementias, then the neurological consequences of diabetes. Also called diabetic neuropathy, this type of pathology has affected 206 million people worldwide, a figure which has tripled since 1990, according to the authors of the study.
Meningitis and epilepsy are next in the ranking. In addition, the neurological consequences of Covid (cognitive impairment and Guillain-Barré syndrome) are in 20th place, representing 2.48 million years of healthy life lost in 2021.
But the most common neurological disorders in 2021 remain tension-type headaches (around 2 billion cases) and migraines (around 1.1 billion cases).
At the origin of this increase in neurological diseases, the aging of the population. Especially since the vast majority of neurological disorders cannot be cured and therefore potentially persist for years until death, the researchers explain. Added to this is increased exposure to environmental risk factors.