3.4 billion people worldwide suffer from neurological problems – that's 43 percent of humanity. This is the latest release in the “Global Burden of Disease” study series for 2021. According to the analysis, stroke, brain damage in newborns, migraines, dementia and nerve damage caused by diabetes contributed the most. Global Burden of Neurological Diseases.
The study, led by Jaime Steinmetz of the University of Washington in Seattle, was published in the journal “The Lancet Neurology.” Overall, the number of cases of diseases of the nervous system worldwide has increased by 59 percent since 1990, Steinmetz cited in a report in the special issue. An international panel of authors evaluated scientific studies published on the topic between January 1980 and October 2023. Developmental trends of individual diseases were analyzed from 1990 to 2021.
An important method of Global Burden of Disease studies is the Daley concept. Tally refers to “disability-adjusted life years.” The years a person is disabled or limited by disease, as well as disease-related deaths, are compared to a hypothetical healthy life expectancy. As the present work describes, the number of tallies increased from 375 million in 1990 to 443 million in 2021 due to the 37 neurological diseases taken into account.
Decline with age
However, during this time the world's population increased and, on average, became older. Taking this into account statistically, tallies from neurological diseases have fallen by 27 per cent and deaths by 34 per cent since 1990 – a figure that varies widely for individual diseases. With the global prevalence of diabetes, nerve damage associated with the disease increased by 92 percent during the study period. Neurological diseases caused by sepsis (plus 70 percent) and malaria (plus 54 percent) became significantly more common in newborns. On the other hand, deaths due to stroke (39 percent), meningitis or encephalitis (62 percent), rabies (70 percent reduction) and tetanus (93 percent) decreased significantly.
Another finding of the work: the burden of neurological diseases is more unevenly distributed in the world. They are lowest in high-income countries in the Asia-Pacific region, such as Japan and South Korea, as well as Australia and New Zealand, and highest in West and Central Africa. The global average is 5,637.6 deaths and 139 deaths per 100,000 people per year. Germany fares best with 3,299.4 tallies and 71.7 deaths per 100,000 people per year. Better medical service may work here compared to most parts of the world.
“Health loss due to diseases of the nervous system disproportionately affects many poor countries, due to the high prevalence of diseases among newborns and children under five years of age,” said Tarun Dua of the World Health Organization (WHO), another author of the study. . Many diseases diagnosed for the first time primarily affect children, whose cases account for 18 percent of neurological diseases worldwide. Brain damage, meningitis and damage to the neural tube are the most serious diseases in newborns.
Gender differences
The frequencies of neurological diseases are also equally distributed between the sexes. While Covid-19, multiple sclerosis and migraines affect women significantly more than men, the opposite is true for attention deficit hyperactivity disorder, traumatic brain injury and autism spectrum disorder.
The study also identifies several modifiable risk factors for preventable neurological diseases. By eliminating the most important risk factors — especially high blood pressure and air pollution — up to 84 percent of strokes can be prevented, Dalys said.
“Neurological diseases cause great suffering to affected people and families and deplete the human capital of societies and economies,” WHO Director-General Tedros Adhanom Ghebreyesus said in a statement. “This study should be an urgent call to strengthen targeted interventions so that increasing numbers of people with neurological diseases can access the high-quality care, treatment and rehabilitation they need.”
