Lancet Neurol

More than 1 in 3 people affected by neurological conditions worldwide

March 20, 2024

Neurological conditions are now the leading cause of ill health and disability worldwide. The overall amount of disability, illness, and premature death (known as disability-adjusted life years, DALYs) caused by neurological conditions increased by 18% from 1990 to 2021, according to a study published in Lancet Neurology.

The World Health Organization (WHO) contributed to the analysis, noting that over 80% of neurological deaths and health loss occur in low- and middle-income countries, and access to treatment varies widely: high-income countries have up to 70 times more neurological professionals per 100,000 people compared to low- and middle-income countries.

WHO also says that eliminating key risk factors—most importantly, high systolic blood pressure and ambient and household air pollution—could prevent up to 84% of stroke DALYs.

Key takeaways:

• Researchers estimated nervous system health loss caused by 37 unique conditions and their associated risk factors globally, regionally, and nationally from 1990 to 2021 in 204 countries and territories.
• Unlike previous surveys, researchers included neurodevelopmental disorders, late-life neurodegeneration, and newly emergent conditions, such as cognitive impairment following COVID-19.
• Globally, the 37 conditions affecting the nervous system were collectively ranked as the leading group cause of DALYs in 2021 (443 million, 95%), affecting 3.40 billion individuals or 43.1% of the global population; global DALY counts attributed to these conditions increased by 18.2% between 1990 and 2021.
• The ten conditions with the highest age-standardized DALYs in 2021 were stroke, neonatal encephalopathy, migraine, Alzheimer's disease and other dementias, diabetic neuropathy, meningitis, epilepsy, neurological complications due to preterm birth, autism spectrum disorder, and nervous system cancer.
• Diabetic neuropathy was the fastest growing neurological condition. The number of people with diabetic neuropathy has more than tripled globally since 1990, rising to 206 million cases in 2021.
• Other conditions such as neurological complications from COVID-19 (for example, cognitive impairment and Guillain-Barré syndrome) didn't previously exist and now account for over 23 million cases.
• However, improved prevention resulted in a 25% decrease since 1990 in the neurological burden and health loss due to other conditions such as tetanus, rabies, meningitis, neural tube defects, stroke, neurocysticercosis, encephalitis, and neonatal encephalopathy.
• Overall, neurological conditions cause more disability and health loss in men compared to women, but there are some conditions like migraine or dementia where women are disproportionately affected.

Sources:

GBD 2021 Nervous System Disorder Collaborators. (2024, March 5). Lancet Neurol. Global, regional, and national burden of disorders affecting the nervous system, 1990-2021: a systematic analysis for the Global Burden of Disease Study 2021. https://pubmed.ncbi.nlm.nih.gov/38493795/

(2024, March 14). World Health Organization. News release. Over 1 in 3 people affected by neurological conditions, the leading cause of illness and disability worldwide. https://www.who.int/news/item/14-03-2024-over-1-in-3-people-affected-by-neurological-conditions--the-leading-cause-of-illness-and-disability-worldwide