Definition and Diagnosis
Stroke is a sudden-onset neurological deficit caused by disruption of blood supply to the brain, either through occlusion of a blood vessel (ischemic stroke, the majority of cases) or rupture of a blood vessel causing bleeding into or around brain tissue (hemorrhagic stroke).
Epidemiology
Stroke is a leading cause of death and long-term disability worldwide, with incidence rising sharply with age, though a meaningful proportion of strokes occur in younger adults. Ischemic stroke accounts for the large majority of cases, with hemorrhagic stroke making up the remainder.
Risk Factors
Major risk factors include hypertension, atrial fibrillation and other cardiac conditions, diabetes, smoking, hyperlipidemia, obesity, physical inactivity, and prior transient ischemic attack or stroke. Hemorrhagic stroke is additionally associated with uncontrolled hypertension and anticoagulant use.
Symptoms and Subtypes
Presentation is typically sudden and includes unilateral weakness or numbness, facial drooping, slurred or absent speech, visual disturbance, imbalance, or severe headache (particularly in hemorrhagic stroke), with specific deficits depending on the brain region affected.
Diagnosis
Diagnosis requires urgent neuroimaging, typically non-contrast CT followed by CT or MR angiography, to distinguish ischemic from hemorrhagic stroke and guide time-sensitive treatment decisions. Rapid clinical assessment tools help identify likely stroke in the pre-hospital setting.
Treatment
For ischemic stroke, treatment centers on rapid restoration of blood flow using intravenous thrombolysis and, for eligible large-vessel occlusions, mechanical thrombectomy, both highly time-dependent. Hemorrhagic stroke management focuses on blood pressure control, reversal of anticoagulation where relevant, and, in selected cases, neurosurgical intervention. Rehabilitation, including physical, occupational, and speech therapy, is central to recovery for all stroke types.
Prognosis
Outcomes depend heavily on stroke type, size, location, and time to treatment, ranging from full recovery to permanent disability or death. Secondary prevention through risk factor control and, where indicated, antiplatelet or anticoagulant therapy substantially reduces the risk of recurrent stroke.
Reference
Sadock, B. J., Sadock, V. A., & Ruiz, P. Kaplan & Sadock's Synopsis of Psychiatry (11th ed.).