There is a significant overlap between the risk factors accounting for cardiovascular events and cerebrovascular events. The INTERHEART study looked at nearly 30,000 patients divided into control and interventional groups to identify these risk factors. Stroke prevention follows a similar principle, of controlling these risk factors. 
Non-modifiable risk factors include
Modifiable risk factors
In most cases, the patient has a combination of modifiable risk factors, i.e., hypertension, diabetes, high cholesterol.
Hypertension is a major risk factor for both ischemic and hemorrhagic stroke. Hypertension is an identified risk factor in up to 90% of all strokes, and it is estimated that up to 40% of all strokes can be prevented with good blood pressure control. Higher blood pressures are associated with a higher risk of stroke, even in normotensive range. The term ‘Pre-hypertension’ has been eliminated in the recent guidelines and normal BP is considered being <120/80 mm Hg. BP over 130/80 mm Hg should be treated in all symptomatic atherosclerotic cardiovascular disease (ASCVD) individuals and in asymptomatic individuals with over 10% risk of 10-year ASCVD risk. For secondary prevention of stroke, antihypertensive treatment should be initiated for BP more than 140/90 mm Hg. Lower BP target (SBP < 130 mm Hg) is recommended only after lacunar stroke. Lifestyle modifications like salt restriction, weight loss, and regular exercise should be a part of comprehensive antihypertensive therapy. Choice of antihypertensive should be individualized based on patient demographics and comorbid conditions.
Diabetes is a major risk factor for ischemic stroke, especially lacunar stroke and large artery stroke. Risk of stroke is tripled in patients with diabetes mellitus of duration over 10 years. Diabetes is a strong risk factor for ischemic stroke and is further associated with other stroke risk factors such as hypertension, abnormal lipid profile, and obesity. So far there is no proven direct risk between diabetes and primary hemorrhagic stroke. Nevertheless, aggressive diabetic control is prudent. Lifestyle modifications and pharmacological treatment should be initiated for a target glycated hemoglobin of <6.5% (48 mmol), along with optimal lipid and blood pressure targets. Aspirin is recommended for diabetic patients with higher ASCVD risk for primary prevention of cardiovascular disease (CVD), although its role in primary stroke prevention is unclear. Metformin - the first line medication for type 2 diabetes mellitus patients also has potential benefits for clinical atherosclerotic disease. Some other hypoglycemic agents like SGLT2 inhibitors- empagliflozin, canagliflozin, GLP-1 receptor agonist- liraglutide, thiazolidinedione- pioglitazone, have shown efficacy for reduction of carotid atherosclerosis and when appropriate diabetic patients with atherosclerotic stroke should receive therapy with such agents. Existing guidelines for glycemic control and lipid and BP targets should be used in diabetic patients who have had a stroke or TIA.
Dyslipidemia- Ischemic stroke risk is increased by high cholesterol levels, whereas low cholesterol levels may increase the risk of hemorrhagic stroke.  Statin treatment reduces the risk of stroke in patients with or at high risk of atherosclerotic disease and even in healthy individuals with LDL < 130 mg/dL and high sensitivity CRP levels > 2mg/L. Despite initial concerns, statin treatment does not increase the risk of hemorrhagic CVA. Estimating total cardiovascular risk is the first step in the medical management of dyslipidemia. Clinical ASCVD, including stroke and TIA, is the major determinant of an individual’s CVD risk. LDL targets are based on risk factors or 10-year risk of ASCVD. American college of endocrinology 2017 guidelines for management of dyslipidemia and prevention of cardiovascular disease recommend LDL target of < 55 mg/dL for extreme risk, < 70 mg/dL for very high risk, < 100 mg/dL for high and moderate risk and < 130 mg/dL for low-risk individuals. Fibrates are recommended for triglycerides >200 mg/dL and HDL < 40 mg/dL. Proprotein Convertase Subtilisin Kexin 9 (PCSK9) inhibitors are recommended for very high-risk individuals unable to reach LDL target of <140 mg/dL or < 100 mg/dL for those with multivessel or rapidly progressive atherosclerotic disease, despite statin therapy with or without ezetimibe therapy or because of inability to tolerate at least three statin medications. A meta-analysis from Cholesterol Treatment Trialists' (CTT) Collaboration has shown that "in individuals with a 5-year risk of major vascular events lower than 10%, each one mmol/L reduction in LDL cholesterol produced an absolute reduction in major vascular events of about 11 per 1000 over 5 years." For secondary prevention, SPARCL trial showed that use of high-dose atorvastatin (80 mg) for cardioembolic stroke/TIA patients led to 43% reduction in risk of fatal recurrent stroke and a 26% reduction in any cardiovascular events. 
Smoking has been associated with a two to a four-time increased risk of ischemic stroke and intracranial bleeds. It is one of the leading preventable risk factors for stroke. It takes two to four years after smoking cessation for the excess risk to go down. Smoking cessation options such as counseling, nicotine replacement therapy, or agents such as bupropion should be offered to all appropriate patients. Passive tobacco smoking should be avoided.
Regular exercise (burning 2000 to 3000 calories per week) has been shown to reduce stroke risk by half.
Obesity- Risk of ischemic stroke is increased by 22% for overweight individuals and by 64% in obese individuals as compared to normal weight individuals.
Diet- American heart association recommends a diet that has increased intake of fruits, vegetables, and whole grains and limited intake of sugar, saturated fat, trans-fat and red meat. Most Mediterranean diets advocate increased consumption of vegetables, whole grains, fruits, nuts, and olive oil. Moderate amounts of fish, poultry, and dairy products are allowed, whereas red meat is to be avoided. It is uncertain whether the health benefits are due to the consumption of the before mentioned food items, or an under-consumption of red meats (and subsequently decreased intake of saturated fats). Absolute risk reduction is approximately three cardiovascular events per 1000 person-years treated (PREDIMED study).
Alcohol- Chronic alcoholism and heavy drinking are risk factors for stroke. J shaped association between alcohol and ischemic stroke risk has been suggested by most studies. There is a protective effect from light to moderate consumption (likely due to an increase in HDL and a decrease in platelet aggregation) and increased risk of stroke with heavy alcohol consumption (due to a hypercoagulable state, alcohol-induced hypertension, cardiomyopathy, and Afib). Stopping or reducing alcohol consumption is recommended for patients with ischemic stroke or TIA.
Sleep disorders have been identified as a risk for stroke in some recent studies. It is a potentially modifiable risk factor. Proper screening and appropriate therapeutic intervention is recommended.
Atrial fibrillation by itself is a risk factor for embolic stroke events - atrial fibrillation leads to about a 1.9% risk of stroke per year, and is responsible for as many as one in six strokes, with a further risk depending on factors such as diabetes, hypertension, age group, previous strokes, heart failure, peripheral vascular disease, previous ischemic cardiac event and gender (higher for females). If all of these risk factors are present along with atrial fibrillation, the risk of embolic stroke is as high as 17% per year. Obviously, anticoagulation is recommended, but that leads to an increased bleeding risk. There are various tools (CHA2DS2VASc score, HAS-BLED score) that can help decide about treating atrial fibrillation with anticoagulation, balancing the benefit and harm of treatment.. There is growing evidence that the new NOACs (Novel Oral Anticoagulants) are as effective, if not superior, to warfarin, and possibly carry fewer bleeding risks. They are now considered first line therapies for stroke risk reduction in an appropriately selected patient with non valvular AF.
Data suggests that vitamin B therapy helps in small vessel brain injury (due to a reduction in Homocysteine) but not large artery disease or cardioembolic disease. B-vitamins have a role in primary stroke prevention and are associated with a reduction in primary stroke risk between 7% to 11% in high vascular risk patients (but no reduction in cardiac events is reported). VITATOPS study showed secondary prevention benefits: a reduction in small artery ischemic strokes from 17% to 14% after intervention, reduction in intracerebral hemorrhage from 18% to 12% after intervention, reduction in recurrent TIAs from 14% to 10% after intervention and reduction in milder strokes from 22% to 18% after intervention.
Antiplatelet therapy is preferred for primary and secondary prevention of atherosclerotic stroke prevention. Daily aspirin has been shown to be beneficial in primary prevention for ischemic cardiac disease, but the data is not so robust for primary prevention in strokes. The data for secondary prevention in ischemic strokes is much more convincing. Significant reduction in stroke recurrence within 2 weeks has been reported if aspirin is initiated within 48 hours of an ischemic stroke. Clopidogrel has shown better outcomes for patients with poly vascular disease and could be considered for secondary stroke prevention of atherosclerotic ischemic stroke patients already on aspirin. Dual antiplatelet therapy (Aspirin and clopidogrel) has shown efficacy but has significantly more bleeding complications than aspirin alone. Increased mortality has been reported with long-term dual antiplatelet therapy after lacunar stroke. Ticagrelor plus aspirin reduced stroke recurrence in patients with ischemic stroke with symptomatic atherosclerotic stenosis of ipsilateral intra or extracranial stenosis as compared to aspirin alone. Antiplatelet therapy is recommended for primary and secondary prevention of stroke, however, it should be weighed against the risk of bleed, and treatment should always be individualized taking into account all risk factors.
Anticoagulation therapy - COMPASS trial published in 2017 compared three antiplatelet regimens- rivaroxaban (2.5 mg twice daily) plus aspirin (100 mg once daily), rivaroxaban (5 mg twice daily), and aspirin (100 mg once daily) in patients with stable atherosclerotic disease (peripheral, coronary, symptomatic carotid artery disease, >50% asymptomatic carotid disease) and found the combination treatment group had a significantly lower risk of major adverse cardiovascular events than with aspirin alone, but significantly higher risk of major bleeding. Combination treatment is not yet added to guidelines but there is a possibility that this could soon be part of treatment guidelines on secondary prevention of atherosclerotic stroke in select patients. Caution is recommended in patients with a high risk of bleeding.
Structural Interventions Considered in Secondary Prevention
The structural cardiac disease can sometimes be corrected, though not all structural defect correction is beneficial for stroke prevention. Antiplatelet therapy is reasonable for patients with PFO and ischemic stroke or TIA. Data regarding recommendation of PFO closure in patients with ischemic stroke is insufficient. Patent foramen ovale correction may be considered in very select patients (high risk on echo, multi-territory infarcts, absence of other significant predisposing risk factos and recurrent strokes despite anticoagulation).
In patients with symptomatic ICA stenosis of >70%, Carotid endarterectomy (CEA) or Carotid Artery Stenosis (CAS) is shown to be beneficial in the first two weeks after an ipsilateral stroke or TIA. CEA is preferred over CAS in older patients (>70 years). Studies have shown a higher peri procedural risk with CAS than CEA. Women have less favorable benefit to risk ratio. Guidelines recommend intervention only if estimated perioperative mortality and morbidity risk is <6% for men and <4% for women. Guidelines recommend considering CEA in asymptomatic patients with over 70% ICA stenosis if their perioperative risk is estimated to be less than 3%, CAS may be considered for high-risk patients. The benefit of carotid intervention for moderate symptomatic and asymptomatic ICA stenosis is unclear so far. There is no benefit in carotid endarterectomy if the carotid is 100% blocked.
Stroke in women
The lifetime risk of stroke and mortality due to stroke is higher in women than men. Some factors that contribute to an increased risk of stroke in women include pregnancy, oral contraceptive use (especially when combined with smoking), preeclampsia/eclampsia, gestational diabetes, migraine with aura, increased risk of atrial fibrillation, hormonal replacement therapy.
Low dose aspirin (from the 12th week of gestation until delivery) and calcium supplementation is recommended for women with hypertension before pregnancy or with a history of pregnancy-related hypertension, to prevent preeclampsia risk. Risk of stroke is increased two folds and hypertension by four folds in women with preeclampsia.
OCPs may be harmful in women especially in women with additional risk factors like smoking and history of thromboembolic events. Aggressive risk factor modification is recommended in women using OCPs. Women should be screened for hypertension before starting hormonal contraception.
Multiple risk factors increase the probability of stroke. Patients with identified risk factors can be educated in risk factors and decrease their risk.
Stroke prevention is the responsibility of all healthcare workers. Besides physicians, nurses and pharmacists can also help educate patients on how to reduce their risk of a stroke. For the pharmacist, the prime responsibility is educating the patient on drug compliance with the statins, anticoagulants and antihypertensive medications. The pharmacist can also play a role in smoking cessation and encouraging a healthy lifestyle. In addition, nurses can also educate the patient on modifiable risk factors and help reduce the risk of stroke. The patient needs to know the importance of blood pressure control and lowering of blood sugars. More important maintaining a healthy body weight and participating in regular exercise should also be emphasized. At the same time, a dietitian should be consulted to educate the patient on the DASH diet and abstaining from alcohol. There is no one method of stroke prevention but a culmination of risk factors that have to be simultaneously reduced. Finally, the patient should be recommended physical therapy or enroll in an exercise program, because the reduction of body weight can greatly improve control of diabetes, hypertension, and stroke. An interprofessional team approach can help lower the risk of stroke.  (Level V)
|||Scheen AJ,Kulbertus H, [Interheart: nine risk factors predict nine out of ten myocardial infarctions]. Revue medicale de Liege. 2004 Nov [PubMed PMID: 15646744]|
|||Yusuf S,Hawken S,Ounpuu S,Dans T,Avezum A,Lanas F,McQueen M,Budaj A,Pais P,Varigos J,Lisheng L, Effect of potentially modifiable risk factors associated with myocardial infarction in 52 countries (the INTERHEART study): case-control study. Lancet (London, England). 2004 Sep 11-17 [PubMed PMID: 15364185]|
|||Feigin VL,Roth GA,Naghavi M,Parmar P,Krishnamurthi R,Chugh S,Mensah GA,Norrving B,Shiue I,Ng M,Estep K,Cercy K,Murray CJL,Forouzanfar MH, Global burden of stroke and risk factors in 188 countries, during 1990-2013: a systematic analysis for the Global Burden of Disease Study 2013. The Lancet. Neurology. 2016 Aug [PubMed PMID: 27291521]|
|||O'Donnell MJ,Chin SL,Rangarajan S,Xavier D,Liu L,Zhang H,Rao-Melacini P,Zhang X,Pais P,Agapay S,Lopez-Jaramillo P,Damasceno A,Langhorne P,McQueen MJ,Rosengren A,Dehghan M,Hankey GJ,Dans AL,Elsayed A,Avezum A,Mondo C,Diener HC,Ryglewicz D,Czlonkowska A,Pogosova N,Weimar C,Iqbal R,Diaz R,Yusoff K,Yusufali A,Oguz A,Wang X,Penaherrera E,Lanas F,Ogah OS,Ogunniyi A,Iversen HK,Malaga G,Rumboldt Z,Oveisgharan S,Al Hussain F,Magazi D,Nilanont Y,Ferguson J,Pare G,Yusuf S, Global and regional effects of potentially modifiable risk factors associated with acute stroke in 32 countries (INTERSTROKE): a case-control study. Lancet (London, England). 2016 Aug 20 [PubMed PMID: 27431356]|
|||Tsivgoulis G,Safouris A,Kim DE,Alexandrov AV, Recent Advances in Primary and Secondary Prevention of Atherosclerotic Stroke. Journal of stroke. 2018 May [PubMed PMID: 29886715]|
|||Katsanos AH,Filippatou A,Manios E,Deftereos S,Parissis J,Frogoudaki A,Vrettou AR,Ikonomidis I,Pikilidou M,Kargiotis O,Voumvourakis K,Alexandrov AW,Alexandrov AV,Tsivgoulis G, Blood Pressure Reduction and Secondary Stroke Prevention: A Systematic Review and Metaregression Analysis of Randomized Clinical Trials. Hypertension (Dallas, Tex. : 1979). 2017 Jan [PubMed PMID: 27802419]|
|||Benavente OR,Coffey CS,Conwit R,Hart RG,McClure LA,Pearce LA,Pergola PE,Szychowski JM, Blood-pressure targets in patients with recent lacunar stroke: the SPS3 randomised trial. Lancet (London, England). 2013 Aug 10 [PubMed PMID: 23726159]|
|||Kernan WN,Ovbiagele B,Black HR,Bravata DM,Chimowitz MI,Ezekowitz MD,Fang MC,Fisher M,Furie KL,Heck DV,Johnston SC,Kasner SE,Kittner SJ,Mitchell PH,Rich MW,Richardson D,Schwamm LH,Wilson JA, Guidelines for the prevention of stroke in patients with stroke and transient ischemic attack: a guideline for healthcare professionals from the American Heart Association/American Stroke Association. Stroke. 2014 Jul [PubMed PMID: 24788967]|
|||Mihaylova B,Emberson J,Blackwell L,Keech A,Simes J,Barnes EH,Voysey M,Gray A,Collins R,Baigent C, The effects of lowering LDL cholesterol with statin therapy in people at low risk of vascular disease: meta-analysis of individual data from 27 randomised trials. Lancet (London, England). 2012 Aug 11 [PubMed PMID: 22607822]|
|||Fitchett DH,Goodman SG,Langer A, Ischemic stroke: a cardiovascular risk equivalent? Lessons learned from the Stroke Prevention by Aggressive Reduction in Cholesterol Levels (SPARCL) trial. The Canadian journal of cardiology. 2008 Sep [PubMed PMID: 18787721]|
|||Guasch-Ferré M,Salas-Salvadó J,Ros E,Estruch R,Corella D,Fitó M,Martínez-González MA, The PREDIMED trial, Mediterranean diet and health outcomes: How strong is the evidence? Nutrition, metabolism, and cardiovascular diseases : NMCD. 2017 Jul [PubMed PMID: 28684083]|
|||McDermott M,Brown DL,Chervin RD, Sleep disorders and the risk of stroke. Expert review of neurotherapeutics. 2018 Jul [PubMed PMID: 29902391]|
|||Diaznuila-Alcázar M,Valcárcel-Paz D,Castillo-Vásquez PD,Santaló-Corcoy M,Bragagnini W,Oliva-Morera JC,Bosch-Peligero E,Martínez-Rubio A, Oral Anticoagulation and Prognosis of Patients with Atrial Fibrillation After Ischemic Stroke: A Real-world Data Analysis. European cardiology. 2017 Dec [PubMed PMID: 30416565]|
|||Bai Y,Deng H,Shantsila A,Lip GY, Rivaroxaban Versus Dabigatran or Warfarin in Real-World Studies of Stroke Prevention in Atrial Fibrillation: Systematic Review and Meta-Analysis. Stroke. 2017 Apr; [PubMed PMID: 28213573]|
|||Spence JD, Cardioembolic stroke: everything has changed. Stroke and vascular neurology. 2018 Jun [PubMed PMID: 30022801]|
|||The International Stroke Trial (IST): a randomised trial of aspirin, subcutaneous heparin, both, or neither among 19435 patients with acute ischaemic stroke. International Stroke Trial Collaborative Group. Lancet (London, England). 1997 May 31 [PubMed PMID: 9174558]|
|||Ringleb PA,Bhatt DL,Hirsch AT,Topol EJ,Hacke W, Benefit of clopidogrel over aspirin is amplified in patients with a history of ischemic events. Stroke. 2004 Feb [PubMed PMID: 14739421]|
|||Hong KS,Lee SH,Kim EG,Cho KH,Chang DI,Rha JH,Bae HJ,Lee KB,Kim DE,Park JM,Kim HY,Cha JK,Yu KH,Lee YS,Lee SJ,Choi JC,Cho YJ,Kwon SU,Kim GM,Sohn SI,Park KY,Kang DW,Sohn CH,Lee J,Yoon BW, Recurrent Ischemic Lesions After Acute Atherothrombotic Stroke: Clopidogrel Plus Aspirin Versus Aspirin Alone. Stroke. 2016 Sep [PubMed PMID: 27418597]|
|||Bhagirath VC,Eikelboom JW,Anand SS, Low-dose rivaroxaban plus aspirin for the prevention of cardiovascular events: an evaluation of COMPASS. Future cardiology. 2018 Nov 12 [PubMed PMID: 30417662]|
|||Meschia JF,Bushnell C,Boden-Albala B,Braun LT,Bravata DM,Chaturvedi S,Creager MA,Eckel RH,Elkind MS,Fornage M,Goldstein LB,Greenberg SM,Horvath SE,Iadecola C,Jauch EC,Moore WS,Wilson JA, Guidelines for the primary prevention of stroke: a statement for healthcare professionals from the American Heart Association/American Stroke Association. Stroke. 2014 Dec [PubMed PMID: 25355838]|
|||Rerkasem K,Rothwell PM, Carotid endarterectomy for symptomatic carotid stenosis. The Cochrane database of systematic reviews. 2011 Apr 13 [PubMed PMID: 21491381]|
|||Hugl B,Oldenburg WA,Neuhauser B,Hakaim AG, Effect of age and gender on restenosis after carotid endarterectomy. Annals of vascular surgery. 2006 Sep [PubMed PMID: 17019658]|
|||Bushnell C,McCullough LD,Awad IA,Chireau MV,Fedder WN,Furie KL,Howard VJ,Lichtman JH,Lisabeth LD,Piña IL,Reeves MJ,Rexrode KM,Saposnik G,Singh V,Towfighi A,Vaccarino V,Walters MR, Guidelines for the prevention of stroke in women: a statement for healthcare professionals from the American Heart Association/American Stroke Association. Stroke. 2014 May [PubMed PMID: 24503673]|
|||Clare CS, Role of the nurse in stroke rehabilitation. Nursing standard (Royal College of Nursing (Great Britain) : 1987). 2018 Aug 22 [PubMed PMID: 30132306]|
|||Musunuru K,Arora P,Cooke JP,Ferguson JF,Hershberger RE,Hickey KT,Lee JM,Lima JAC,Loscalzo J,Pereira NL,Russell MW,Shah SH,Sheikh F,Wang TJ,MacRae CA, Interdisciplinary Models for Research and Clinical Endeavors in Genomic Medicine: A Scientific Statement From the American Heart Association. Circulation. Genomic and precision medicine. 2018 Jun [PubMed PMID: 29844141]|
|||van den Dries CJ,Oudega R,Elvan A,Rutten FH,van de Leur SJCM,Bilo HJG,Hoes AW,Moons KGM,Geersing GJ, Integrated management of atrial fibrillation including tailoring of anticoagulation in primary care: study design of the ALL-IN cluster randomised trial. BMJ open. 2017 Sep 18 [PubMed PMID: 28928175]|
|||Tulek Z,Poulsen I,Gillis K,Jönsson AC, Nursing care for stroke patients: A survey of current practice in 11 European countries. Journal of clinical nursing. 2018 Feb [PubMed PMID: 28815784]|
|||Jhaveri MM,Benjamin-Garner R,Rianon N,Sherer M,Francisco G,Vahidy F,Kobayashi K,Gaber M,Shoemake P,Vu K,Trevino A,Grotta J,Savitz S, Telemedicine-guided education on secondary stroke and fall prevention following inpatient rehabilitation for Texas patients with stroke and their caregivers: a feasibility pilot study. BMJ open. 2017 Sep 3 [PubMed PMID: 28871024]|
|||Chekroud SR,Gueorguieva R,Zheutlin AB,Paulus M,Krumholz HM,Krystal JH,Chekroud AM, Association between physical exercise and mental health in 1·2 million individuals in the USA between 2011 and 2015: a cross-sectional study. The lancet. Psychiatry. 2018 Aug 8 [PubMed PMID: 30099000]|
|||Lynch EA,Jones TM,Simpson DB,Fini NA,Kuys SS,Borschmann K,Kramer S,Johnson L,Callisaya ML,Mahendran N,Janssen H,English C, Activity monitors for increasing physical activity in adult stroke survivors. The Cochrane database of systematic reviews. 2018 Jul 27 [PubMed PMID: 30051462]|