Apoplexy and dementia present risk factors in common, most of which can be managed. It is estimated that about 35% of dementia cases could be prevented by stroke prevention.
In the opening speech of this year's EAN (European Academy of Neurology) Congress, held virtually in May 2020, the President of the EAN, Prof. Claudio L. Bassetti, emphasized the high burden caused by neurological diseases: worldwide, they rank first in terms of causes of disability and second in terms of causes of death.1,2 Nearly half of disability-adjusted life years (DALYs) of all neurological diseases are caused by stroke (42%) and 10% by dementia.3 Since apoplexy doubles the probability of developing dementia4 and 90% of all strokes are preventable5,6, minimizing the risk of apoplexy at the population level would be essential.7
The worldwide burden of disease caused by apoplexy and dementia is increasing. If current trends continue, 200 million apoplexy survivors and 106 million dementia patients can be expected by 2050 - and in each subsequent year, we may observe 30 million new strokes, 12 million apoplexy deaths, and almost 5 million deaths from dementia.8 It is therefore urgent to address the limitations of current prevention strategies.
The WSO (World Stroke Organization) has called for joint prevention of apoplexy and dementia, which has been supported by all major international organizations for neurological and cardiovascular health. The current issue of Lancet Neurology also takes up the key points of the global WSO declaration once again.8
A growing body of evidence suggests that entire populations have a better cognitive function and lower rates of dementia when they experience better education and fewer vascular risk factors (e.g. reduced smoking prevalence).7 Years ago, a large cohort study had already shown that controlling only five lifestyle factors (smoking, physical activity, diet, alcohol consumption, weight) could reduce the risk of stroke by 47% in women and 35% in men.9
Therefore, according to the WSO, the focus should be on population-wide strategies, particularly on reducing lifelong exposure to risk factors for apoplexy, dementia, cardiovascular complications, and other risk factors associated with non-communicable diseases (including environmental factors such as air pollution).
The potential of education and motivation strategies has also been underused. Ideally, community interventions (such as health workers in low and middle-income countries or qualified teachers in high-income countries), pharmacological, and non-pharmacological interventions should be combined.
A growing understanding of pathophysiology has revealed the interrelation between cerebrovascular diseases and neurodegeneration. This has resulted in new therapeutic targets for the protection of the endothelium, the blood-brain barrier (BBB), and other components of the neurovascular unit (NVU). Targeting the amyloid angiopathy aspects of inflammation and genetic manipulation is also seen as promising by some scientists.7
The WSO further recommends that the classification of people into those at low, medium, and high risk of apoplexy and cardiovascular disease be abandoned and advocates instead for a holistic approach to prevention.
The organization also emphasizes the role of policymakers in implementing these cornerstones: for example, by introducing taxes on smoking, sugar, or alcohol to reduce their consumption and promote healthy behavior, or by tackling problems such as air pollution. The authors also see a need for change in societal determinants, from socio-economic differences and inequitable access to health care facilities to issues such as junk food availability. In the current Lancet article, it is stated that "revenues from such taxation could and should be reinvested in public health to further improve prevention, research, and healthcare".8
References:
1. European Academy of Neurology Congress 2020. https://multiplesclerosisacademy.org/2020/05/29/european-academy-of-neurology-congress-2020/.
2. Feigin, V. L. et al. The global burden of neurological disorders: translating evidence into policy. Lancet Neurol 19, 255–265 (2020).
3. Nichols, E. et al. Global, regional, and national burden of Alzheimer’s disease and other dementias, 1990–2016: a systematic analysis for the Global Burden of Disease Study 2016. The Lancet Neurology 18, 88–106 (2019).
4. Kuźma, E. et al. Stroke, and dementia risk: A systematic review and meta-analysis. Alzheimer's Dement 14, 1416–1426 (2018).
5. O’Donnell, M. J. et al. Risk factors for ischaemic and intracerebral hemorrhagic stroke in 22 countries (the INTERSTROKE study): a case-control study. Lancet 376, 112–123 (2010).
6. Feigin, V. L. et al. Global burden of stroke and risk factors in 188 countries, during 1990-2013: a systematic analysis for the Global Burden of Disease Study 2013. Lancet Neurol 15, 913–924 (2016). 7. Hachinski, V. et al. Preventing dementia by preventing stroke: The Berlin Manifesto. Alzheimer’s & Dementia 15, 961–984 (2019).
8. Brainin, M. et al. Global prevention of stroke and dementia: the WSO Declaration. The Lancet Neurology 19, 487–488 (2020).
9. Chiuve Stephanie E. et al. Primary Prevention of Stroke by Healthy Lifestyle. Circulation 118, 947–954 (2008).