The stroke chain of survival captures the key milestones in the stroke survivor journey. The chain spans from the time from stroke symptom recognition through to rehabilitation (see Figure 1). Understanding the key elements on the stroke patient journey can help better contextualise the role of the community pharmacist in this chain. This CPD article relates to the three main points on the stroke chain of survival, where the community pharmacist is directly involved in stroke care:
Insert Figure 1
A stroke occurs when blood supply to part of the brain is interrupted or reduced, preventing brain tissue from getting oxygen and nutrients (> 24 hours). Whereas a TIA (or mini stroke) is a sudden onset of focal neurological symptoms of stroke (numbness, weakness, slurred speech), which last less than 24 hours (or sudden monocular blindness), then cease. Within the stroke community differing opinions exist on the nuanced differences between the conditions. However, broadly speaking, duration of symptoms, cause and prognosis differ between a stroke and TIA.
Globally, stroke was the second-leading cause of death and the third leading cause of death and disability in 2019. Stroke is the leading cause of disability and the second leading cause of death in Ireland, with approximately 8,000 strokes occurring each year.
There are two primary causes of stroke: a blocked artery (ischaemic stroke) or a blood vessel leaking or bursting (haemorrhagic stroke). Ischaemic accounts for approximately 85% of all strokes.
An ischaemic stroke occurs when the brain’s blood vessels become narrowed or blocked, causing severely reduced blood flow (ischaemia).
Figure 2: Depiction of ischaemic stroke (image from Irish National Audit of Stroke: National Report 2019).
A Haemorrhagic stroke occurs when a blood vessel in the brain leaks or ruptures.
Figure 3: Depiction of haemorrhage stroke (image from Irish National Audit of Stroke: National Report 2019).
Stroke symptoms can commonly be described using the FAST acronym. However more recent screening tools, such as BEFAST include a greater array of symptoms, which of which are atypical.
Figure 4: (a) FAST and (b) BEFAST acronyms for stroke symptom recognition
Stroke is a time sensitive emergency. Approximately two million neurons die every minute a large vessel occlusion stroke remains untreated. Each hour that goes by where stroke/TIA treatment fails to occur, the brain loses as many neurons as it would during roughly 3.6 years of typical aging. This is the key point when it comes to these cerebrovascular diseases. For haemorrhagic stroke rapid blood pressure management can be a key treatment option.
Transient Ischaemic attack (TIA)
The highest risk of stroke is within the four weeks post TIA.
Stroke/TIA risk factors can be divided into those that are modifiable and non-modifiable:
| Non-modifiable |
| Age |
| Low birth weight |
| Race/ethnicity |
| Sex |
| Genetic factors |
| Modifiable | |
| Hypertension | Other cardiac conditions |
| Dyslipidaemia | Asymptomatic carotid artery stenosis |
| Atrial fibrillation | Obstructive sleep apnoea |
| Diabetes | Sickle cell disease |
| Obesity | Other factors, for example migraine |
| Physical inactivity | Diet and nutrition |
| Smoking | |
Key point: Maximum gain in stroke prevention is by early intervention
Stroke can be prevented through effective management of risk factors. Primary stroke prevention strategies are predominantly targeted at behavioural (for example, smoking cessation and lifestyle modifications), and pharmacological interventions (i.e., preventative medications). There is also a need to consider interrelating structural factors that support, or hinder, prevention actions and behaviours of individuals. These are summarized in Figure 5.
Figure 5: Action plan for governments and other policy makers for primary stroke prevention measures at the population (i.e., socioeconomic, environmental, and behavioural), and individual levels
In the context of primary prevention three key behavioural and lifestyle areas can be targeted:
As pharmacists we can play a key role engaging with our patients around these areas; we can individually discuss any of these factors relevant to individuals or take part in health promotion activities to reach wider audiences.
In terms of pharmacological management, four main conditions are targeted: dyslipidaemia; atrial fibrillation; hypertension; and diabetes.
High total cholesterol is a risk factor for cardiovascular disease and ischaemic stroke. Strong evidence recommends lifestyle modification and prescription of a statin to control lipid levels. However alternatives to stations such as ezetimibe, fibrates, PCSK 9 inhibitors are also available.
Atrial fibrillation is an age-related condition, which is a key risk factor for stroke. Having atrial fibrillation is associated with a five-fold increased risk of stroke. Atrial-fibrillation related strokes have twice the mortality rate of non-AF-related strokes. Furthermore, among those who survive functional outcomes are poorer. Once atrial fibrillation is identified management can be initiated, which typically involves an anticoagulant. Again, pharmacists have an essential role in this context in the screening and detection of atrial fibrillation, stroke risk identification, and stroke risk reduction, alongside patient counselling and medicines optimisation.
The type of stroke, ischaemic or haemorrhagic, usually determines the nature of secondary pharmacological prevention. Pharmacological secondary prevention concerns:
In this context, pharmacists, as members of the multidisciplinary team (MDT) have a key role in shared decision making, contraindications and adherence to secondary prevention medications.
In cases where thrombolysis is not administered, initial treatment typically involves aspirin at a dosage of 300mg daily for a maximum of two weeks. For individuals allergic to aspirin, clopidogrel at a dose of 75mg once daily is an alternative. Subsequently, a decision regarding long-term management is necessary. Options for ongoing prevention include clopidogrel 75mg once daily, aspirin 75mg once daily, or a combination of aspirin 75mg once daily with dipyridamole MR 200mg twice daily. Clinical efficacy between clopidogrel and aspirin plus dipyridamole is comparable, with the latter offering potential advantages such as reduced pill burden and a more favourable side effect profile from the patient’s perspective. Aspirin alone is deemed superior to dipyridamole monotherapy, while the benefits of aspirin or dipyridamole alone are notably less compared to dual therapy. Antiplatelet therapy is typically lifelong following a stroke or transient ischemic attack (TIA), although some individuals discontinue after two years. Nevertheless, evidence suggests that the benefits persist beyond this timeframe.
In most cases anticoagulants are not initiated until two weeks after the ischaemic event. This is due to the risk of haemorrhagic transformation. Haemorrhagic transformation (HT) or haemorrhagic conversion is a medical complication that can occur in the brain following an acute ischemic stroke, a condition in which blood flow to the brain is blocked. If a patient has a contraindication to anticoagulants, antiplatelet agents can be considered. However, they offer significantly less benefit than anticoagulants in this context. Anticoagulant options include warfarin or a direct oral anticoagulant (apixaban, rivaroxaban, edoxaban, dabigatran).
Hypertension increases the risk of recurrence of haemorrhagic and ischaemic stroke/TIA. The effective management of hypertension for secondary prevention of the three conditions is vital. A recent meta-analysis showed that intensive BP lowering to levels <130/80 mmHg significantly reduced the risk of recurrent stroke compared to standard management with BP levels <140/90 mmHg. Although these are generally the limits considered, guidelines vary and adaption for individual circumstances can be required. Relevant hypertension guidelines, such as the European Society of Cardiology and the National Institute for Health and Care Excellence, should be followed in this context.
Lipid modification is important for the secondary prevention of vascular disease including stroke. Although the relationship between cholesterol and stroke is less certain than hypertension, available evidence favours cholesterol reduction after an ischaemic stroke. Some evidence suggest that statin therapy reduces ischaemic stroke risk but can increase the risk of haemorrhagic stroke. Hence, statins are usually not initiated until 48 hours after ischaemic stroke and should not be used in the initial weeks after haemorrhagic stroke, unless compelling indications exist.
High-intensity station therapy, for example atorvastatin 80 mg daily, is typically recommended, or the maximum tolerated dose. Treatment goals for ischaemic stroke and TIA is to have LDL-cholesterol < 1.8 mmol/l. If targets are not achieved ezetimibe can be considered.
This stroke type can be induced by anticoagulants, antiplatelets, thrombolysis and cocaine. Therefore, medications that precipitated the initial bleed should be avoided. There is also a risk of haemorrhagic transformation after ischaemic stroke. This condition can be precipitated by antiplatelet agents and statins. Blood pressure reduction is crucial in the context of haemorrhagic stroke.
Consider the impact of aphasia or reduced cognitive function post stroke when counselling stroke survivors. In terms of aphasia, you may need to adapt your communication style when counselling the stroke survivor on their medications. The Irish Association for Speech and Language therapists have great resources for aphasia awareness (see iaslt.ie > Supporting People’s Communication & Swallowing > Aphasia). Providing written as well as oral information and encouraging the stroke survivor to have a family member/carer present for the consultation may also facilitate more effective communication. In terms of dysphagia, alternative formulations may need to be sourced and discussed with prescribers. Finally, stroke survivors and family members can be signposted to their local stroke support group, such as the Irish Heart Foundation and Croi.
The role of the community pharmacist in stroke/TIA prevention and care is multi-faceted. The community marks the point of departure and return of the stroke survivor. Community pharmacists have a broad-ranging and beneficial role in stroke/ TIA care and prevention. Their accessibility and range of interventions, including screening, detection, risk factor modifications, and medicines optimisation, show that the community pharmacist has a core function in stroke/TIA prevention, and the holistic care of a stroke survivor. There is also the potential to reduce re-hospitalisation, mortality rates and economic burden through these roles, undertaken by the community pharmacist.
References available on request.
