In 2021, 3.4 billion people experienced a nervous system condition, according to a major new analysis from the Global Burden of Disease, Injuries, and Risk Factors Study (GBD) The total number of DALYs is increasing in large part due to aging and growing populations worldwide. The most prevalent neurological disorders in 2021 were tension-type headaches (around 2 billion cases), migraine, Alzheimer's disease and other dementias.