Stroke prevention

By: Dr Michael B. Fawale

1. Stroke Prevention Dr Michael B. Fawale Medicine Department, OAU, Ile-Ife [email protected]

2. Stroke Prevention Stroke is best treated by prevention! Up to 90% of strokes are preventable Stroke prevention hinges on risk modification Treatment of cardiovascular risk diseases Lifestyle modification

3. Stroke Prevention Primary prevention of stroke refers to the treatment of individuals with no previous history of stroke Secondary prevention refers to the treatment of individuals who have already had a stroke or transient ischemic attack (TIA). Most primary and secondary stroke prevention recommendations focus on ischemic stroke, but some apply to hemorrhagic stroke, or to cerebral venous thrombosis.

4. Secondary Prevention of Stroke

5. Secondary Prevention of Stroke Secondary prevention can be summarized by the mnemonic A, B, C, D, E, as follows: A - Antiaggregants (aspirin, clopidogrel , extended-release dipyridamole , ticlopidine ) and anticoagulants (warfarin) B - Blood pressure–lowering medications C - Cessation of cigarette smoking, cholesterol-lowering medications, carotid revascularization D - Diet E - Exercise

6. Transient Ischemic Attack The epidemiology essentially mirrors that of stroke > 10% of TIAs will develop CI within 90 days (4-8% of CI will recur within 90 days) 2.6% of TIAs will develop other major CV events within 90 days 10-15% of patients have a stroke within 3 months, with half occurring within 48 hours CF: Amaurosis fugax , transient stoke-like syndromes

7. Transient Ischemic Attack C ontroversy exists regarding the need for admission Admission to a "rapid evaluation unit" or "observation unit", dropped the 90-day stroke risk from 10 % to 4-5% No controversy regarding the need for urgent evaluation, risk stratification, and initiation of stroke prevention therapy

8. Initial Evaluation Level of consciousness and neurologic examination are usually at the patient's baseline. Initial assessment is aimed at excluding conditions that can mimic a TIA, eg , ICH, hypoglycemia , seizure. Laboratory studies- within 24 hours RPG, ECG, CT, FBC , coagulation studies, E,U.Cr . MRI preferred to CT Echo, carotid and vertebral doppler uss

9. Risk Stratification – ABCD 2 A ge ≥ 60 years (1 ) B lood pressure 140/ 90 mm Hg on first evaluation (1 ) C linical symptoms of focal weakness with the spell (2) or speech impairment without weakness (1 ) D uration ≥ 60 minutes (2) or 10 to 59 minutes (1 ) D iabetes (1).

10. Risk Stratification – ABCD 2 2-day risk of stroke % for scores of 0 or 1 1.3 % for 2 or 3 4.1 % for 4 or 5 8.1 % for 6 or 7

11. Decision to Admit If presents within 72 hours, hospitalize if: ABCD 2 score of 3 ABCD 2 score of 0 to 2 and uncertainty that diagnostic workup can be completed within 2 days as an outpatient ABCD 2 score of 0 to 2 and other evidence that indicates the patient's event was caused by focal ischemia - AHA

12. Management Admit for Restoration of Vital Signs Cardiac monitoring, pulse oximetry Intravenous access Management of hypertension, hyperglycemia etc Non- cardioembolic TIA Aspirin (50-325 mg/d), combination aspirin/extended-release dipyridamole , and clopidogrel

13. Management Cardioembolic TIA Atrial fibrillation, Complete heart block, MI, DCM, RHD After a TIA, long-term anticoagulation with warfarin (goal INR, 2-3) is typically recommended. LMW heparin if warfarin is interrupted Aspirin , 325 mg/d Mechanical prosthetic valves, warfarin (goal INR 2.5-3.5), aspirin, 75-100 mg/d Bioprosthetic valves, warfarin (goal INR 2-3 )

14. Management

15. Management Carotid Stenosis C arotid endarterectomy (CEA) if Ipsilateral severe (70% to 99 %) for asymptomatic carotid stenosis Ipsilateral moderate (50% to 69%) for symptomatic stenosis depending on patient-specific factors - age, sex, and comorbidities (CAS – an alternative) Stenosis <50%, no indication for CEA/CAS CEA within 2 weeks is reasonable

16. Antiplatelets Aspirin A 15% relative risk reduction in vascular events (stroke, death, MI) compared with placebo Dose varies from 75mg to 325 mg daily Clopidogrel - 75 mg daily Had a relative risk reduction of ~ 9% for stroke, death, and MI compared with aspirin

17. Ticlopidine – 250 mg twice daily Relative risk reduction of ~ 9% for stroke, death, and MI compared with aspirin Side effects (diarrhea, skin rash, and reversible agranulocytosis ) limit use Dipyridamole – 200mg b.d Aspirin + extended-release dipyridamole is more effective than aspirin alone. Antiplatelets

18. Primary Prevention of Stroke

19. Prevention Risk modification Hypertension Antihypertensive therapy reduces stroke risk by about 38% Reduction of diastolic BP by 6 mmHg reduces stroke risk by more than 33% Reduction of systolic BP by 3mmHg reduces risk by 8% Diabetes No demonstrated benefit in stroke reduction with tight glycemic control BP control and statins reduce stroke risk in DM

20. Prevention Aspirin - 25% risk reduction Carotid endarterectomy : symptomatic atherosclerotic stenosis of > 70% in the carotid artery High Blood Cholesterol Stroke risk reduction of 27% to 32% is achieved with statins 25% reduction in TIAs Smoking Cessation Reduces risk by 50% within 1 y; to baseline after 5 years

21. Prevention Avoid alcohol drinking Recommendation: No drinks at all Weight control An average weight loss of 5.1 kg reduced systolic BP by 4.4 mmHg and diastolic BP by 3.6 mmHg Exercise Recommendation: 30 minutes of moderate-intensity activity daily

22. Atrial fibrillation ( nonvalvular ) RR = 2.6 – 4.5 Warfarin vs control: 64% risk reduction Aspirin vs placebo: 19% risk reduction Warfarin vs aspirin: 39% risk reduction

23. Asymptomatic carotid stenosis RR = 2.0 50% reduction with endarterectomy Aggressive management of other identifiable vascular risk factors

24. Weight Control No clinical trial has tested the effects of weight reduction on stroke risk An average weight loss of 5.1 kg reduced systolic BP by 4.4 mmHg and diastolic BP by 3.6 mmHg Therefore, weight reduction is reasonable as a means of reducing stroke risk Don’t just advise, set SMART weight management goals

25. Physical activity Mechanisms: BP, DM, weight, plasma fibrinogen, platelet activity & plasma tPA activity and HDL-cholesterol. Recommendation (The 2008 Physical Activity Guidelines for Americans ): At least 150 minutes per week of moderate intensity or 75 minutes per week of vigorous intensity aerobic physical activity or an equivalent combination of moderate and vigorous intensity aerobic activity

26. Sickle Cell Disease Screening with TCD starting at age 2 years Optimal interval not yet established, more frequently in younger children and with borderline abnormal TCD velocities Transfusion therapy (target reduction of Hb S from a baseline of >90% to <30 %) Reduced risk from 10% to 1% Hydroxyurea or bone marrow transplantation

27. < 15% Saturated fatty acids Polyunsaturated fatty acids Monounsaturated fatty acids 8%-10% < 10% Recommended Daily Nutrient Content Carbohydrate > 55% Protein 15% Fat < 30% Cholesterol: <300 mg/d Fiber: 20-30 g/d

28. Healthy Eating Pyramid

29. Diet Carbohydrates Include at least one starchy food in each main meal Use refined carbohydrates sparingly Fats Low-fat dairy products and low saturated and total fat diets reduce BP and stroke risk Yoruba diet has lower mean cholesterol level (166mg/dl) compared to that of the African Americans (220mg/dl) ( Ogunniyi et al ,2000)

30. Diet Proteins Red Meat - Use Sparingly Fish, Poultry, and Eggs - 0-2 times a day Nuts and Legumes - 1- 3 times a day Nuts and legumes are an excellent source of protein, fiber, vitamins, and minerals. Examples: Brown beans, soya beans. Contain healthy fat, good for the heart . Milk A good source of calcium Try to stick to low or no fat milk

31. Fruits and Vegetables Increased fruit and vegetable consumption is associated with a reduced risk of stroke in a dose-response fashion For each 1-serving/day increment in fruit and vegetable intake, the risk of stroke was reduced by 6% - Nurses’ Health Study & the Health Professionals’ Follow-Up Study Vegetables - to be taken in abundance, every meal, every day. Fruits (2-3 times a day )

32. Salt 75% of the salt we eat is already in food when we buy it Avoid foods high in salt Fast foods, canned foods, tomato ketchup, mayonnaise, roasted nuts, smoked meat and fish. No added salt at table Recommended daily intake of table salt for adults: not more than 6g a day: around one full teaspoon

33. Conclusion Stroke is a disease of major public health importance in Nigeria & mortality is still very high Recognition by patients and care providers that stroke is a medical emergency will change the current picture Stroke is preventable and prevention is the only affordable option for developing countries TIA is not benign

34. Thank You