Understanding transient ischaemic attack

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1 chemistanddruggist.co.uk/update UPDATE Module 1679 PREMIUM CPD CONTENT FOR 1 per week Buy UPDATEPLUS for 52+VAT Visit chemistanddruggist.co.uk/update-plus for full details This module covers: Causes, symptoms and management of transient ischaemic attack (TIA) Information about risk factors for stroke after a TIA Treatments such as antiplatelet therapy and surgery The role of pharmacists in TIA management NOVEMBER» Blood disorders and wounds Understanding anaemia Nov 2 Transient ischaemic attack Nov 16 Woundcare Nov 23 Genetic bleeding disorders Nov 30 Understanding transient ischaemic attack Sagal Hashi Traditionally a transient ischaemic attack (TIA) has been defined as a mini stroke, with signs and symptoms that are resolved within 24 hours. Generally, the symptoms of a TIA do not last longer than 10 to 30 minutes and are normally fully resolved within an hour. Advances in neuroimaging have meant that the definition of a TIA has started to move away from the arbitrary 24-hour timeframe and towards a more tissue-based diagnosis. Up to a third of patients with TIA symptoms lasting less than 24 hours have been found to have an infarction (permanent tissue injury) on early imaging. Thus 2009 guidelines from the American Heart Association (AHA) and the American Stroke Association (ASA), define a TIA as a transient episode of neurologic dysfunction caused by focal brain, spinal cord, or retinal ischemia, without acute infarction. TIAs are caused by a temporary reduction or cessation of cerebral blood flow. Symptoms depend on where the neurovascular disruption occurs and are a result of partial or total occlusion, usually because of an acute thromboembolic event or atherosclerosis. The aetiology of a TIA is usually the same as a stroke: large artery atherosclerosis cardiac sources, most commonly secondary to atrial fibrillation (AF) small vessel disease, leading to lacunar events (without any outside symptoms): these arise from atherosclerotic process, for example, hypertension and hypercholesterolemia other causes, such as dissection, hypoperfusion, sickle cell anaemia and infarcts/ TIAs of undetermined causes. A TIA should always be treated as a medical Coloured angiogram of the left carotid artery (black, centre) in the neck of a 56-year-old patient. This artery has severe stenosis (narrowing, lower centre), which reduces the blood flow to the brain and can cause a stroke emergency, as the diagnosis of TIA is always retrospective. Unfortunately, a large proportion of TIAs remain undiagnosed, with about half never receiving medical attention. Major strokes are often preceded by TIAs, but these are not reported by patients because of a lack of awareness. The incidence of TIA preceding stroke is hard to be sure of, but the 90-day risk of stroke after a TIA has been reported as being as high as 17 per cent, with the greatest risk apparent in the first week. 1, 2 Approximately 20,000 people in the UK will have a first TIA each year. 3 In 2005, the national audit office for reducing brain damage reported that more than 900,000 people in England were living with the effects of stroke, with half of these dependent on other people for help with everyday activities. 3 This is why TIAs are sometimes referred to as a warning sign: appropriate management of a TIA is essential to reduce the stroke burden. TIA symptoms/presentation TIAs have the same presentation as stroke, but the symptoms will resolve. As with stroke, the pattern of impairment can aid diagnosis. Patients may present with the following: sudden numbness or weakness of the face, arm or leg, especially on one side of the body sudden confusion, trouble speaking or understanding sudden trouble seeing in one or both eyes sudden trouble walking, dizziness loss of balance or coordination. In people with sudden onset of neurological symptoms, a validated tool such as FAST (Face Arm Speech Time) should be used outside hospital to screen for a diagnosis of stroke or TIA. This test is aimed at early recognition of symptoms: Face: Has their face fallen to one side? Can they smile? Arms: Can they raise both arms and keep them there? Speech: Is their speech slurred? Time to call 999 if you see any single one of these signs. 14 Chemist+Druggist

2 DID YOU KNOW? UPDATE users can upgrade to UPDATEPLUS for only 20+VAT Visit chemistanddruggist.co.uk/update-plus for full details Stroke risk The national stroke strategy recommends that care pathways should be in place to ensure that patients with suspected TIA are immediately referred for urgent specialist assessment and investigation, so that a secondary prevention management plan can be established. Once a TIA has been diagnosed, doctors often use an algorithm to identify risk of stroke following a TIA known as an ABCD2 score. This tool focuses on five key clinical indicators (see right). Higher ABCD2 scores are associated with a greater risk of stroke. Patients with an ABCD2 score of four or above are considered high risk. Patients with crescendo TIA (two or more TIAs in a week) are also automatically considered high risk. Differential diagnosis of TIA This is almost identical to that of a stroke, and examples include hypoglycaemia, seizure, brain tumours, migraine, worsening of an old stroke, systemic infection, alcohol excess, vestibular dysfunction, subdural haemorrhage, demyelinating disease, Bell s palsy and benign paroxysmal positional vertigo. Risk factors As stroke and TIA have the same pathophysiology, they are also subject to the same risk factors, which include: hypertension diabetes hypercholesterolemia smoking atrial fibrillation alcohol consumption obesity and lack of physical exercise psychological stress. Hypertension In the acute ischaemic stroke setting, blood pressure is not usually lowered unless it is a medical emergency such as hypertensive encephalopathy. An exception would be a candidate for thrombolysis, where blood pressure must be less than 185/140mmHg. However, hypertension in patients with a TIA is one of the most important modifiable risk factors, with approximately 50 per cent of strokes caused by hypertension. Often blood pressure remains poorly controlled in a large proportion of patients after a TIA, and under-treatment and poor adherence are important factors. There is a critical role for community pharmacists to continue to assess their patients understanding of the importance of medication and how this can contribute to reducing their overall stroke risk factors. Blood pressure control should be tailored to the individual patient. However, aiming below 140/90mmHg, with tighter control in diabetic patients, is recommended for most patients. Table 1. ABCD2 scoring table Classification Risk factors Points A Age 60 years 1 B Blood pressure: systolic 140mmHg or diastolic 90mmHg 1 C D Clinical features: any unilateral weakness Speech impairment without weakness Duration 60 minutes Duration 10 to 59 minutes D2 Diabetes 1 Meta-analyses of randomised controlled trials have shown that blood pressure lowering is associated with a 30 to 40 per cent reduction in stroke risk. 2 The Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure stresses the importance of lifestyle modifications in managing hypertension. The following changes can reduce blood pressure and should be recommended to all patients: weight loss (maintain a normal BMI) salt restriction, consuming no more than 100mmol per day increased consumption of fruits, vegetables and low-fat dairy products regular aerobic physical activity limited alcohol consumption. Smoking Smoking is an independent risk factor for stroke and there is strong and consistent evidence of it increasing stroke risk. Patients should be given advice on all smoking cessation services. Hypercholesterolemia High cholesterol is an associated stroke risk factor. Patients who have presented with stroke or TIA should be counselled on lifestyle changes to lower total cholesterol and the addition of a statin to bring it below 4mmol/l. Atrial fibrillation When TIAs are caused by a blood clot originating in the heart, due to AF, then anticoagulation therapy should be started if there are no contraindications. Anticoagulation in AF Age is a risk factor for atrial fibrillation (AF) with a 0.5 per cent risk at age 50 to 59 years, to nearly 9 per cent at age 80 to 89 years. There is also a 30 to 43 per cent risk of a recurrent stroke within five years after the first stroke. The risk of stroke in people with non-valvular AF can be reduced with anticoagulation. The decision regarding which agent to use should be based on the potential benefit (prevention of stroke) versus the risk (bleeding risk) on an individual patient basis. Patients diagnosed with an ischaemic stroke should not be routinely anticoagulated for AF within the first two weeks of their stroke symptoms. They are usually treated with aspirin 300mg for two weeks then anticoagulated. As TIAs have fully resolved, then early anticoagulation for AF is recommended if there are no other contraindications. Warfarin Numerous trials have shown warfarin s superiority over aspirin and placebo for the prevention of stroke in patients with AF. Warfarin is a drug with variable dosing, but the INR (international normalised ratio) should be kept in the range of two to three. Good INR control is essential in providing stroke prevention. Novel oral anticoagulants (NOACs) Rivoroxaban, dabigatran and apixaban have all been reviewed by Nice in They are licensed for stroke prevention in the treatment of non-valvular AF in patients with one or more of the following risk factors: prior stroke or TIA, age 75 years or over, hypertension, diabetes mellitus, symptomatic heart failure. NOAC treatments are summarised in table 2 on the final page of this PDF. The decision about whether to start treatment with one of these NOACs should be made after an informed discussion between the clinician and the patient about the risks and benefits of the NOAC compared with warfarin. For people who are taking warfarin, the potential risks and benefits of switching to a NOAC should be considered in light of their level of INR control. Management and investigations A detailed neurological assessment is an essential criterion for the diagnosis of TIA, focusing on the neurovascular distribution suggested by patients symptoms. Nice guidelines recommend that patients deemed as having high risk TIAs should be started on aspirin therapy. They should also see a stroke specialist within 24 hours of symptom onset. If the specialist is unsure which area of the brain was affected by the TIA, the person should also have an urgent brain scan. (Nice suggests that urgent means within 24 hours of symptom onset.) This Chemist+Druggist

3 Don t fall behind STAY UP TO DATE Keep your CPD UP to DATE with UPDATEPLUS from C+D Training UPDATEPLUS is a unique CPD package With UPDATEPLUS you ll get a new learning module every week plus access to our online library and bite- sized learning Try it for FREE today Visit chemistanddruggist.co.uk/ update-plus and start your free trial can either be an MRI (magnetic resonance imaging) or CT (computed tomography), although MRI is preferred. Anyone at lower risk of stroke should also be started on daily aspirin. They should be assessed by a specialist as soon as possible (within a week). Again, if the specialist is unsure which area of the brain was affected, the person should have a brain scan within a week of symptom onset. Patients should have detailed assessments of their stroke risk factors and treatment should be optimised. Carotid endarterectomy Carotid endarterectomy (CEA) is a surgical procedure used to unblock carotid arteries, the main blood vessels that supply the head and neck. In the UK, approximately 45,000 strokes are attributed to carotid artery disease. Carotid imaging is required to define the extent of carotid artery narrowing to determine whether surgery is needed. People with stable neurological symptoms from acute non-disabling stroke or TIA who have symptomatic carotid stenosis of 50 to 99 per cent (according to the NASCET North American Symptomatic Carotid Endarterectomy Trial criteria), should be assessed and referred for carotid endarterectomy within one week of onset of stroke or TIA symptoms. They should undergo surgery within a maximum of two weeks of onset of symptoms. They should also receive best medical treatment (control of blood pressure, antiplatelet agents, cholesterol lowering through diet and drugs, and lifestyle advice). TIA patients with carotid stenosis of less than 50 per cent using NASCET criteria should not have routine surgery but be given best medical treatment. Antiplatelet therapy If there are no contraindications, then all patients should be placed on an antiplatelet agent post TIA, such as: 4 clopidogrel 75mg once daily monotherapy is used for long-term secondary prevention of ischaemic stroke aspirin 75mg once daily, plus dipyridamole M/R 200mg twice daily is recommended for TIA prevention clopidogrel 75mg once daily. Should be used in TIA patients if aspirin is not tolerated dipyridamole monotherapy should be used as the last line, if neither aspirin or clopidogrel can be tolerated by the patient. There is, however, variation in local practice, with a large number of clinicians opting for clopidogrel monotherapy for the treatment of TIAs and strokes, as they essentially have the same aetiology and pathophysiology. Further pharmacist involvement It is essential that pharmacists should be able to recognise, and counsel patients about how to recognise, a TIA. Half of all MURs must be in patients that fall within the national target groups. One of these target groups is high risk drugs, which includes antiplatelets and anticoagulants. TIA and stroke patients should be on antiplatelets or anticoagulants, and are an important group for community pharmacists to target for MURs to ensure they have greater understanding of the importance of their medication. During these sessions, it is essential to educate patients about stroke symptoms and the need to call emergency services immediately if any of these develop. Information about the NHS stroke Act Fast campaign and how to order support materials can be found on the NHS Choices website at nhs.uk/actfast/pages/stroke.aspx Sagal Hashi is a specialist stroke pharmacist at University College London Hospitals NHS Foundation Trust References 1. Guidelines for the prevention of stroke in patients with stroke or TIA. Stroke 2011;42: Rothwell PM, Warlow CP. Timing of TIAs preceding stroke: time window for prevention is very short. Neurology 2005;64: Diagnosis and initial management of stroke and TIA: Nice clinical guideline 68: issued July 2008 (guidance.nice.org.uk/cg68). 4. Nice TA210 Vascular disease clopidogrel and dipyridamole (Review of TA90): quick reference guide. 15 December Coull A: Lovett J: Rothwell P, for the Oxford Vascular Study. Population-based study of early risk of stroke after TIA or minor stroke: implications for public education and organisation of services. BMJ 2004;328: tool.pdf 7. Early assessment and treatment of people who have had a stroke or TIA. Information about Nice clinical guideline 68. Issue date: July 2008, cg68publicinfo.pdf 18 Chemist+Druggist

4 Looking for tips to get the most out of your MURs? Try» C+D s popular MUR Zone chemistanddruggist.co.uk/mur-zone 5 minute test Sign up to take the 5 Minute Test and get your answers marked online: chemistanddruggist.co.uk/update Take the 5 Minute Test 1. The symptoms of a TIA usually last about 60 to 90 minutes. 2. TIAs are caused by a temporary reduction or cessation of cerebral blood flow. 3. The 90-day risk of stroke after a TIA has been shown to be around 46 per cent. 4. Approximately 20,000 people in the UK will have a first TIA each year. 5. TIA symptoms include sudden numbness or weakness of the face, arm or leg and sudden confusion. 6. When assessing TIA patients, those with a ABCD2 of six or below are considered to be at low risk of stroke. 7. Approximately 25 per cent of strokes are Reflect What are the causes of a TIA? What investigations and assessments are carried out in patients who have had a TIA? How can stroke risk be reduced after a TIA? Plan This article discusses the causes, symptoms and management of transient ischaemic attack. Information about risk factors for stroke after a TIA, treatments such as surgery and antiplatelet therapy and the role of the pharmacist in TIA management are also included. Act Read the Update article and the suggested reading (below), then take the 5 Minute Test (above). Update and Update Plus subscribers can then access their answers and a pre-filled CPD logsheet at co.uk/mycpd. Read more about TIAs on the NHS Choices website tinyurl.com/tiattack1 Revise your knowledge of antiplatelet and anticoagulant therapy from the BNF sections 2.8 and 2.9 Read the MUR tips for secondary caused by hypertension. 8. Nice guidelines recommend that patients deemed as high risk TIAs should be started on aspirin therapy. 9. In the UK approximately 45,000 strokes are attributed to carotid artery disease. 10. Dipyridamole monotherapy is recommended first line for stroke prevention in TIA patients. SIGN UP TO UPDATEPLUS Sign up for Update Plus, C+D s premium CPD package for pharmacists and pharmacy technicians. Go to chemistanddruggist.co.uk/ update-plus and sign up for 52+VAT today that s just 1+VAT a week Tips for your CPD entry on understanding anaemia prevention of ischaemic stroke/tias on the C+D website tinyurl.com/tiattack2 Identify any patients who may benefit from an MUR or more information about reducing stroke risk Find out more about the Act Fast campaign on the NHS Choices website. Consider displaying some of the information. Make sure your counter assistants can also recognise stroke or TIA symptoms tinyurl.com/tiattack3 Evaluate Are you now confident in your knowledge about TIAs? Can you recognise the symptoms and give advice to patients about their treatments or lifestyle to help reduce stroke risk? ASK THE EXPERT November is blood disorders and wounds month and our expert is on hand to answer your queries. From anaemia to transient ischaemic attacks submit your questions by steve.titmarsh@ubm.com A CASE FOR A QUIET CONVERSATION THE CASE: A man in his mid 20 s comes to the counter and asks for a word in private. He says he s concerned as he s recently noticed that he s starting to lose his hair. THE CONVERSATION: Most men feel uncomfortable talking about hair loss, so offering to take him to a consulting room or quiet area is a good starting point. Ask questions and check it is hereditary hair loss. If it is, REGAINE Foam can be a good recommendation as it is scientifically proven to help stop and even reverse hair loss, 1 and results show that 9 out of 10 men said it helped them keep or re-grow hair. 2 Furthermore, REGAINE works best on men who are just starting to lose their hair. 3 5% Minoxidil FOAM REGAINE for Men Extra Strength Scalp Foam 5% w/w cutaneous foam Confidence begins with a conversation REGAINE for Men Extra Strength Scalp Foam 5% w/w Cutaneous Foam (minoxidil) for treatment of alopecia androgenetica in men. Legal cat: Triple pack: P; Single pack: GSL. MA Holder: McNeil Products Ltd, Foundation Park, Maidenhead, Berks, SL6 3UG. Information about this product, including adverse reactions, precautions, contra-indications, and method of use can be found at References: 1. REGAINE for Men Extra Strength Scalp Foam 5% w/w Cutaneous Foam SmPC. 2. Olsen EA et al. J Am Acad Dermatol 2007; 57: Khandpur S et al. J Dermatol 2002; 29: Date of preparation: February 2013 ID: UK/RE/

5 Table 2: Summary of novel oral anticoagulants Drug name Dosing Mechanism of action Dabigatran (Pradaxa) Rivoraxaban (Xarelto) Apixaban (Eliquis) 150mg bd 110mg bd (if dose is reduced) 20mg od 5mg bd 2.5mg bd (if dose is reduced) Direct thrombin Direct factor Xa Direct factor Xa Trial name RE-LY Rocket-AF Aristotle Additional dosing information Dose reduction in patients aged 80 years and over and those on verapamil and with renal impairment. Individual assessment on dose reduction in patients with an increased bleeding risk and low CHADS score (a prediction tool for stroke in AF patients). Not suitable in patients with creatine clearance less than 30 ml/min Do not open capsule, swallow whole. Not suitable for blister packs. Note also licensed for venous thromboembolism prophylaxis (different dosing) Must be taken with food Dose reduction in patients with renal impairments Not recommended in patients with a creatine clearance less than 15ml/min Dose reduction in patients aged 80 years and over, body weight less than 60kg, or serum creatinine greater than 1.5mg/dL 20 Chemist+Druggist