A two-part Series published in this week's special stroke edition of The Lancet reviews the progress made in treatments for those who have had a full-blown stroke or minor stroke or transient ischemic attack (TIA), and stresses the need for immediate intervention with the appropriate medication and/or surgical procedure in those cases. It also highlights the improvements made in stroke rehabilitation care over the past two decades, but notes the large evidence gaps remain.
In the first paper Professor Peter M Rothwell, John Radcliffe Hospital, Oxford, and University of Oxford, UK, and colleagues say that, without improvements in prevention, the burden of stroke will continue to increase over the next 20 years due largely to the ageing world population, especially in developing countries. Stroke causes 1 in 10 of all deaths worldwide and will rise from sixth to fourth in the list of largest causes of disability by 2030. Costs of stroke care are extremely high, with 4% of health-care spending in developed countries allocated; the UK spends some £9 billion (GBP) on treating stroke, while in the USA the estimate is US$40 billion. The indirect costs—related to dementia, depression, falls, fractures, and epilepsy—are also immense.
Primary prevention (ie, preventing a first stroke) is the most important aspect of reducing the burden of stroke, but around 1 in 3 strokes occur in people with previous stroke or TIA, and these recurrent strokes are usually more severe than first strokes and more likely to cause dementia. Yet use of a range of interventions now available has more than halved the risk of a second stroke in those with previous stroke or TIA over the last 25 years.
Rothwell and colleagues say: "Secondary prevention with antiplatelet agents, antihypertensives, statins and anticoagulation, and carotid endarterectomy as appropriate should be initiated urgently after TIA or minor stroke because of the high risks of early stroke recurrence."
They add that, for long-term secondary prevention, most guidelines recommend aspirin plus dipyridamole or clopidogrel as the first-line approach after cerebral ischaemia of arterial origin (some 80% of cases). With a cardiac origin (eg, embolism from atrial fibrillation) (the other 20%), new interventions such as factor Xa and thrombin inhibitors are challenging the current standard of vitamin K anatagonists.
Finally, the authors conclude that lipid-lowering (using statins) and blood-pressure lowering treatments are warranted after both types of cerebral ischaemia, each with the capacity to reduce the risk of recurrent stroke by around 20%.
In the second paper, Professor Peter Langhorne, Royal Infirmary, Glasgow, and Glasgow University, UK, and colleagues assess the developments in stroke rehabilitation care in the past two decades, looking at the progression from assessment, through to goal setting, intervention, and eventual re-assessment of recovery. The most common effect of stroke is reduced mobility, while impairment of speech, language and other functions is also common.
The authors say: "Evidence of impairment-focused therapies enhancing true neurological repair in the human brain is still scarce. By contrast, strong evidence shows that task-oriented training can assist the natural pattern of functional recovery, which supports the view that functional recovery is driven mainly by adaptive strategies that compensate for impaired body functions."
They note that evidence supports the provision of stroke rehabilitation in well coordinated multi-disciplinary stroke units (that include physiotherapy) and through teams that continue the same function in the patient's home. Constraint-induced movement therapy (a treatment that emphasises repeated practice with the affected limb) and robotics (the use of robotic devices to assist repeat practice of skills) are potentially beneficial treatments for motor recovery of the arm. To improve gait, fitness training, high-intensity therapy, and repetitive task-training are all promising. Occupational therapy can improve activities of daily living, but there is little clear evidence on how best to improve loss of speech functions.
The authors add that there is a lack of consistency between researchers and clinicians in the use of terminology that describes changes in motor ability after stroke. They say: "The substantial growth in the number of clinical trials of rehabilitation in the past 10 years shows the increased interest of rehabilitation clinicians in evidence-based care and the success of the development of research capacity across the many groups of health professionals who deliver rehabilitation to people with stroke."
They conclude: "Several ongoing trials of repetitive task training, early mobilisation, treadmill training, physical fitness training, and speech and language training for aphasia and dysarthria are high-quality, multicentre, multidisciplinary studies of complex interventions… The results of these trials will hopefully provide better information to guide future practice."
See also Lancet Editorial on Stroke (link below)
A second and indirectly related Editorial in this week's Lancet discusses salt intake and risk of cardiovascular disease, criticising a recent paper in the Journal of the American Medical Association (JAMA), in which lower urinary sodium excretion surprisingly predicted higher cardiovascular disease (CVD) mortality, leading to assertions of a lack of proven benefit of a low salt diet.
The Editorial concludes: "This study is disappointingly weak and contributes little to our understanding of salt and disease. It is likely to confuse public perceptions of the importance of salt as a risk factor for high blood pressure, heart disease, and stroke. Questions of intervention and outcome, such as sodium intake and CVD events, cannot be answered by small observational studies. It is dangerous to jump to conclusions on the basis of single studies and ignore the totality of evidence. At a time when CVD is the world's leading cause of death and excess dietary sodium has convincingly been shown to be a serious public health hazard, the results of this work should neither change thinking nor practice."
Professor Peter M Rothwell, John Radcliffe Hospital, Oxford, and University of Oxford, UK. T) +44 1865 231610 E) peter.rothwell@clneuro.ox.ac.uk
Professor Peter Langhorne, Academic Royal Infirmary, Glasgow, and Glasgow University, UK. T) +44 141 211 4976 E) peter.langhorne@glasgow.ac.uk
The Lancet Press Office. T) +44 (0) 20 7424 4949 E) tony.kirby@lancet.com
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The Lancet