Description

The sudden onset of a focal neurologic deficit(s) resulting from either infarction or hemorrhage within the brain

• Two broad categories: ischemic (thrombotic or embolic) (87%) and hemorrhagic (13%)
• Hemorrhage: intracerebral or subarachnoid
• Synonym(s): CVA; cerebral infarct
• Related terms: transient ischemic attack (TIA), a transient episode of neurologic dysfunction due to focal ischemia without permanent infarction on imaging (See “Transient Ischemic Attack (TIA).”)

Pediatric Considerations

• Incidence: 2 to 13/100,000
• Frequent risk factors: arteriopathies (53%), cardiac disorders (31%), and infection (24%) (1)

Epidemiology

Incidence
Annual incidence in the United States is ~795,000.

Prevalence

• Prevalence in the United States: 550/100,000
• Predominant age: Risk increases >45 years of age; highest during the 7th and 8th decades
• Predominant sex: male > female at younger age but higher incidence in women with age ≥75 years

Etiology and Pathophysiology

• 87% of strokes are ischemic, three main subtypes: thrombosis, embolism, and systemic hypoperfusion. Large vessel atherothrombotic strokes often involve the origin of the internal carotid artery. Small vessel lacunar strokes are commonly due to lipohyalinosis occlusion. Embolic strokes are largely from a cardiac source (due to left atrial thrombus, atrial fibrillation, recent MI, valve disease, or mechanical valves) or ascending aortic atheromatous disease (>4 mm) (2).
• 13% of strokes are hemorrhagic; most commonly due to hypertension (HTN). Other causes include intracranial vascular malformations (cavernous angiomas, AVMs), cerebral amyloid angiopathy (lobar hemorrhages in elderly), and anticoagulation (2).
• Fibromuscular dysplasia (rare), vasculitis, or drug use (cocaine, amphetamines) are other causes of stroke.

Genetics
Stroke is a polygenic multifactorial disease.

Risk Factors

• Uncontrollable: age, gender, race, family history/genetics, prior stroke or TIA
• Controllable/modifiable/treatable
  • Metabolic: diabetes, dyslipidemia
  • Lifestyle: smoking, alcohol, cocaine/amphetamine use, physical inactivity
  • Cardiovascular: HTN, atrial fibrillation, valvular heart disease, endocarditis, recent MI, severe carotid artery stenosis, hypercoagulable states, patent foramen ovale (2)

General Prevention

Smoking cessation, regular exercise, avoid prolonged physical inactivity (3), weight control to maintain BMI<30 and maximize glucose control, low-salt diet, moderate alcohol use; control BP; manage hyperlipidemia; antiplatelet therapy (e.g., aspirin) in high-risk persons; treat anticoagulation therapy for nonvalvular atrial fibrillation.

Commonly Associated Conditions

Coronary artery disease is the major cause of death in the first 5 years after a stroke.