World Stroke Awareness Day
There are 15 million people worldwide who suffer a stroke each year. According to the World Health Organization (WHO), stroke is the second leading cause of death for people above the age of 60 years, and the fifth leading cause in people aged 15 to 59 years old. Each year, nearly six million people worldwide die from stroke and one in four people worldwide will have a stroke in their lifetime. Stroke claims more than twice as many lives as AIDS. In fact, stroke continues to be responsible for more deaths annually than those attributed to AIDS, tuberculosis and malaria combined.
Incidence and Epidemiology
Most of the population of South Africa (SA) is undergoing a rapid epidemiological transition with increased exposure to, and development of, stroke risk factors, together with ageing. In SA, stroke is responsible for 25 000 deaths annually and 95 000 years (sic) lived with disability (Benjamin; Bryer & Lucas, et al. 2016). In 2000, stroke was the third most common cause of death in SA, after HIV/AIDS and coronary artery disease. Black women had the highest mortality rate from stroke (160 per 100 000), while mortality was lowest in white men (72 per 100 000). Deaths in the black population were double those in the white population. The risk of stroke increases with age: there are more stroke deaths in older South Africans, where stroke is the most common cause of death of people older than 50 years (Emberson; Lees & Lyden, et al. 2014). The Southern African Stroke Prevention Initiative (SASPI) study provided the only community-based data on the prevalence of stroke in SA.
Classification of Stroke
Stroke and its aetiology are fundamentally classified into two major types: brain ischaemia and brain haemorrhage (due to ICH and SAH). Ischaemia followed by recirculation into the infarcted area may convert into haemorrhagic infarcts and may aggravate cerebral oedema owing to disruption of the blood-brain barrier.
Acute ischaemic strokes (AIS) however, may be secondary to atherosclerosis, thrombosis (i.e. local in situ obstruction of an artery from arteriosclerosis, dissection or fibromuscular dysplasia), embolism (i.e. particles of debris originating elsewhere that block arterial access to a particular brain region) or systemic hypoperfusion (Emberson; Lees & Lyden, et al. 2014).
Blood disorders causing coagulopathy are an uncommon primary cause of stroke. Transient ischaemic attack (TIA) is traditionally defined clinically by the temporary nature of the associated neurological symptoms, which usually last a few minutes. Most signs and symptoms disappear within an hour, though rarely symptoms may last up to 24 hours. The signs and symptoms of a TIA resemble those found early in a stroke and may include sudden onset of e.g. weakness, numbness or paralysis in your face, arm or leg, typically on one side of the body (Mayo Foundation for Medical Education and Research: 1998-2020). Despite its global impact, the term stroke is not consistently defined in clinical practice, in clinical research or in assessment of the public’s health. Advances in basic science, neuropathology, and neuroimaging have improved the understanding of ischaemia, infarction, and haemorrhage in the CNS (Sacco; Kasner; Broderick, et al. An updated definition of stroke for the 21st century: (A statement for healthcare professionals from the American Heart Association/American Stroke Association. https://doi.org/10.1161/STR.0b013e318296aeca).
As stated previously, stroke is the second-leading cause of death worldwide after ischaemic heart disease (Naghavi; Foreman; Shibuya; Aboyans, et al. 2012). During 2010, stroke was responsible for 5.3 million deaths or 1 in 10 deaths worldwide. The absolute number of people affected by stroke has been increasing yearly since 1990, along with the numbers of disabled stroke survivors and deaths related to stroke (Krishnamurth; Feigin; Forouzanfar; Mensah; Connor & Bennett, et al. Global and regional burden of first-ever ischaemic and haemorrhagic stroke during 1990–2010: findings from the Global Burden of Disease Study 2010. Lancet Glob Health. 2013; 1:e259–81). It is estimated that, if current trends continue, by 2030 there will be 20 million annual stroke deaths and 70 million stroke survivors worldwide.
Management of Stroke
Unfortunately, most SA patients with stroke seen in primary healthcare settings struggle to regularly access basic medicine, such as aspirin, statins, and antihypertensive and antidiabetic medications. Despite the high disease burden, some progress has been made and stroke is no longer a hopeless condition. Devoted units for patients who have suffered a stroke were the first step in improving care, with several randomised trials showing that death and handicap could be prevented in 50 patients for every 1 000 admitted (Krishnamurthi; Feigin, & Fourzanfar, et al. 2010) & Whitehead;.Baalbergen: 2019).
In the same study was found that intravenous thrombolysis indicates the next step forward, with death and disability prevented in 143 patients for every 1 000 treated with intravenous recombinant tissue plasminogen activator therapy within 3 hours of symptom onset (Emberson; Lees & Lyden, et al. 2014). It was later evident that the 3-hour time window for thrombolysis administration could be increased to 4.5 hours; and, if the trial entry and exclusion criteria were met, up to 30% of all AIS patients could benefit.
The most recent evolution has been mechanical thrombectomy, performed in the catheterisation laboratory, where the occluding cerebral vessel clot is extracted. Thrombectomy is a highly effective treatment, preventing death and disability in 200 patients for every 1 000 treated.
Post-stroke rehabilitation should be delivered by an interdisciplinary team experienced in the rehabilitation process, with the aim of improving patient outcomes by decreasing the chance of developing secondary complications and maximising a patient’s independence.