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The Global Prevalence of Brain Disease

Brain disease impacts billions of people around the world — and research is essential to bring that number to zero.

Brain disease is a global issue, and a new study released by The Lancet Neurology shows its impact is significant. Over 1 in 3 people around the world are affected by neurological conditions, meaning it is now the leading cause of illness and disability worldwide

Based on 2021 data from the Global Burden of Disease, Injuries, and Risk Factor Study (GBD), the findings indicate a growing issue. The overall amount of disability, illness, and premature death (known as disability-adjusted life years, DALYs) caused by neurological conditions has increased by 18% since 1990.

At the American Brain Foundation, we’ve always approached brain disease as a global issue. We are committed to research that is focused on the whole brain, which will make a difference for people around the world. Just as the different parts of the brain and different brain diseases are interconnected, all people are connected on a global level. By investing in research, we can save lives worldwide.

A Comprehensive Look

Neurological conditions have a range of causes, symptoms, and outcomes. Some are treatable or preventable, while others cause lifelong disability or have high mortality rates. This recent report provides the most comprehensive estimate of neurological health loss globally. The study examined a category of 37 unique conditions, which was expanded from a previous grouping of 15 conditions.

The ten neurological conditions with the greatest DALYs were stroke, neonatal encephalopathy (neurological dysfunction in an infant at or around delivery), migraine, Alzheimer’s disease and other dementias, diabetic neuropathy (nerve damage as a symptom of diabetes), meningitis, epilepsy, neurological complications due to preterm birth, autism spectrum disorder, and nervous system cancer.

Global Disparities

While brain diseases, disorders, and injuries impact people around the world, the study notes global and regional disparities for certain populations. Over 80% of neurological deaths and health loss occur in low- and middle-income countries. DALY rates were highest in western and central sub-Saharan Africa and lowest in Australasia and high-income Asia Pacific. For children under 5 years old, DALY rates were approximately 18 times higher in sub-Saharan Africa than in Australasia. 

These disparities are likely due to limited access to specialized treatment and rehabilitation services. High-income countries have up to 70 times more neurological professionals per 100,000 people than low- and middle-income countries.

Not only do certain populations have a lack of access to healthcare and neurological care, but they are also often underrepresented in research studies and careers in medicine and research. The American Brain Foundation supports research in neurodisparities with our annual Next Generation Research Grant. We aim to reduce neurological health care disparities by investing in research that helps us understand how social determinants and environment influence brain health.

The Importance of Investing in Research

In 2021, 3.4 billion individuals — 43.1% of the global population — were affected by a neurological condition, and these conditions caused 11.1 million deaths. 

Quantifying the global burden helps raise brain health on the public health agenda. The findings of this study show that these conditions have been under-recognized, their rates are increasing, and they are unevenly distributed geographically and socioeconomically. As the leading cause of overall global disease burden, nervous system health loss should be a public health priority.

The study makes clear what the American Brain Foundation has always known: Investing in research is the only way to achieve better treatments, prevention strategies, and cures for brain diseases.

Many brain diseases do not have cures, and access to quality medical care is limited in some places. Because of that, it’s important to gain a better understanding of risk factors that we have the power to change. If we can reduce the impact of these risk factors — through individual contributions, targeted interventions, and policy options — we could potentially decrease the burden of certain neurological conditions and increase brain health at all levels.

As referenced in the study, in 2022, the World Health Organization adopted a global action plan to promote brain health, improve diagnosis, treatment, and prevention of neurological disorders, and foster research in these areas. Its ultimate goal is to reduce the stigma, impact, and burden of neurological disorders, as well as improve the quality of life of all people affected by these conditions.

We believe worldwide awareness and effort is necessary for advancing advocacy, research, and the public health approach. The American Brain Foundation is committed to doing our part in these efforts. While the numbers may be alarming, this study only further motivates us to continue fulfilling our mission and investing in brain disease research.

The American Brain Foundation is committed to finding cures for brain diseases. Donate today to make a difference. With your help, we can all experience life without brain disease.