Global brain health—the time to act is now

Abstract

The recently published 2021 Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) data on neurological disorders represents a comprehensive analysis of 37 neurological conditions, amounting to a staggering 443 million disability-adjusted life-years (DALYs) affecting 43·1% of the global population.1GBD 2021 Nervous System Disorders CollaboratorsGlobal, regional, and national burden of disorders affecting the nervous system, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021.Lancet Neurol. 2024; (published online March 14.)https://doi.org/10.1016/S1474-4422(24)00038-3Google Scholar The ten leading conditions, in descending order, are stroke, neonatal encephalopathy, migraine, dementias, diabetic neuropathy, meningitis, idiopathic epilepsy, neurological complications from preterm birth, autism spectrum disorder, and nervous system cancer. Interestingly, data disaggregation shows that the burden of neurological disorders lies largely with low-income and middle-income countries (LMICs).1GBD 2021 Nervous System Disorders CollaboratorsGlobal, regional, and national burden of disorders affecting the nervous system, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021.Lancet Neurol. 2024; (published online March 14.)https://doi.org/10.1016/S1474-4422(24)00038-3Google Scholar, 2Knauss S Stelzle D Emmrich JV Korsnes MS Sejvar JJ Winkler AS An emphasis on neurology in low and middle-income countries.Lancet Neurol. 2019; 18: 1078-1079Summary Full Text Full Text PDF PubMed Scopus (13) Google Scholar In addition, the 2019 global burden of psychiatric disorders was estimated at 125 million DALYs.3GBD 2019 Mental Disorders CollaboratorsGlobal, regional, and national burden of 12 mental disorders in 204 countries and territories, 1990–2019: a systematic analysis for the Global Burden of Disease Study 2019.Lancet Psychiatry. 2022; 9: 137-150Summary Full Text Full Text PDF PubMed Scopus (1098) Google Scholar Although there exists some overlap between the nervous system burden quantified recently and the mental health figures for 2019, most notably because of the inclusion of autism spectrum and attention-deficit hyperactivity disorders in both studies, other highly prevalent conditions are not reflected in either study—ie, alcohol and drug use disorders and self-harm.1GBD 2021 Nervous System Disorders CollaboratorsGlobal, regional, and national burden of disorders affecting the nervous system, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021.Lancet Neurol. 2024; (published online March 14.)https://doi.org/10.1016/S1474-4422(24)00038-3Google Scholar, 3GBD 2019 Mental Disorders CollaboratorsGlobal, regional, and national burden of 12 mental disorders in 204 countries and territories, 1990–2019: a systematic analysis for the Global Burden of Disease Study 2019.Lancet Psychiatry. 2022; 9: 137-150Summary Full Text Full Text PDF PubMed Scopus (1098) Google Scholar Irrespective of some gaps, the message is clear: the burden from global brain disorders is enormous and increasing further, disproportionately affecting LMICs and surpassing any other disease category, including cancer and cardiovascular diseases. Sadly, resource allocation to the global brain health agenda, including mental health, is disproportionate to its burden and remains virtually absent. Concerted action regarding brain health seems of paramount importance in the light of global health efforts, social change, demographic transition, and increasing disease burden. For example, all countries—even in sub-Saharan Africa, which has one of the youngest populations in the world—are experiencing rapid demographic shifts towards an ageing population. In addition, governments are increasing the statutory retirement age, which means people older than 60 years are staying in the workforce for longer. These trends have important and far-reaching implications for global economic and social development—eg, affecting the knowledge economy, which is an important factor in countries' competitiveness. An immediate focus on brain health is, therefore, required. Brain health transcends traditionally separate disciplines, including neurology, neurosurgery, mental health, and neurodevelopment. However, despite the ever-growing socioeconomic importance of brain health and the increased use of the term brain health in multiple settings, this term has been a cause of debate. The definition currently proposed by WHO states: “Brain health is the state of brain functioning across cognitive, sensory, social-emotional, behavioural, and motor domains, allowing a person to realize their full potential over the life course, irrespective of the presence or absence of disorders.”4WHOOptimizing brain health across the life course: WHO position paper.https://www.who.int/publications/i/item/9789240054561Date accessed: December 7, 2023Google Scholar This definition suggests that brain health is not a binary concept involving optimal or suboptimal functioning but encompasses a spectrum ranging from good brain health and wellbeing to disorders and consequent disabilities. The WHO Intersectoral Global Action Plan on epilepsy and other neurological disorders (WHO IGAP) provides evidence-based guidance to countries to achieve optimal brain health, with clear, measurable targets.5WHOIntersectoral global action plan on epilepsy and other neurological disorders 2022–2031.https://www.who.int/publications/i/item/9789240076624Date accessed: December 7, 2023Google Scholar The goal of the WHO IGAP is to “reduce the stigma, impact, and burden of neurological disorders including their associated mortality, morbidity, and disability, and to improve the quality of life of people with neurological disorders, carers, and their families”. The WHO IGAP states that “to achieve the vision and goals of the IGAP, the prevention, treatment, and care of epilepsy and other neurological disorders should be strengthened” with an interdisciplinary and multisectoral focus “wherever possible, using existing entry points and synergies to achieve the best results for all”.5WHOIntersectoral global action plan on epilepsy and other neurological disorders 2022–2031.https://www.who.int/publications/i/item/9789240076624Date accessed: December 7, 2023Google Scholar For example, ideas around mental health care systems and systems for chronic disease might also work for neurological disorders—eg, epilepsy, dementia, and stroke.6Patel V Saxena S Lund C et al.Transforming mental health systems globally: principles and policy recommendations.Lancet. 2023; 402: 656-666Summary Full Text Full Text PDF PubMed Google Scholar, 7Patel V Re-imagining the care delivery system for chronic conditions.Lancet Reg Health Southeast Asia. 2023; 13100232Google Scholar In addition, efforts to promote optimal brain health, in combination with preventive measures, coincide with managing risk factors for other high-burden non-communicable diseases, creating an advantageous situation for advancing brain health in collaboration with other disciplines and sectors.8Ding C Wu Y Chen X et al.Global, regional, and national burden and attributable risk factors of neurological disorders: the Global Burden of Disease study 1990–2019.Front Public Health. 2022; 10952161Crossref Scopus (44) Google Scholar At a time when the world is not on track to meet UN Sustainable Development Goal 3.4 (reducing premature mortality from non-communicable diseases), optimising brain health provides an overarching framework to drive progress on several fronts. However, it is impossible to address the large burden of global brain disorders unless radical change happens now. Such change should include the scaling up of evidence-based interventions through better integration of health-care services, including diagnostic and management approaches that transcend disease categories and provide a continuum of care tailored to the needs of the individual. In addition, there is a need for concerted action that targets known risk factors to reduce the incidence of brain disorders and promote brain health. Large investment in prevention—eg, through improved brain health (digital) literacy—will be necessary. Innovative solutions to gaps and needs (eg, human resources, digital technology, big data, community engagement, and financing) must be sought, and research in different global contexts must be promoted to generate new knowledge on brain health, especially novel strategies for prevention and care. National and global implementation of the WHO IGAP must be strongly supported, including a call for a research agenda, measurable indicators, implementation pathways, and monitoring and evaluation plans. Recommendations for WHO IGAP implementation need to be developed with consideration of national and regional particularities and entry points, on the basis of brain health principles such as equity and approaches involving life course and human rights. ASW, SG, SC, and KBP contributed equally to authorship. This study was not funded. We thank colleagues from WHO (Katrin Seeher, Neerja Chowdhary, and Nicoline Schiess) for their support in drafting the manuscript. TD is a staff member of WHO. ASW received funding from the German Federal Ministry of Education and Research for her work on brain health. The authors alone are responsible for the views expressed in this article, which do not necessarily represent the views, decisions, or policies of the institutions with which the authors are affiliated. We declare no competing interests.

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