Does stroke subtype influence prognosis and treatment type?

This study assessed whether the subtype of stroke affects prognosis and influences effectiveness of secondary prevention methods.

A stroke is a sudden interruption of blood flow to the brain. An ischemic stroke is a type of stroke that occurs when the arteries supplying the brain become narrowed or blocked, causing severely reduced blood flow (ischemia). The ischemic stroke subtypes include stroke due to small vessel occlusion or SVO, which occurs when there is a blockage of the small blood vessels of the brain (branches of the large vessels supplying the brain), cardioembolic stroke or CE, which occurs when a blood clot forms in the heart and is swept through the bloodstream to lodge in the narrower brain arteries, and large artery atherosclerosis or LAA, which refers to the build-up of cholesterol in the walls of the large sized arteries of the brain. After an ischemic stroke or transient ischemic attack or TIA (defined as a smaller stroke that occurs when blood flow to a part of the brain stops for a brief period of time), patients are given treatment to prevent recurrence of the stroke, known as secondary prevention. Prognosis (defined as a prediction of the probable course and outcome of a disease) and the effectiveness of secondary prevention may differ among stroke patients. This study investigated whether stroke subtype relates to prognosis and effectiveness of secondary prevention.

The study involved 28471 patients who had one of the major subtypes of ischemic stroke. 13066 patients had a LAA stroke, 9208 patients had a SVO stroke and 6197 patients had a CE stroke. After 2.4 years of follow up, the CE group had a 41% higher mortality risk than the LAA group, while the SVO group showed the smallest risk, with a 34% lower risk than the LAA group.

Regarding secondary prevention, antiplatelet polytherapy (treatment using multiple drugs that decrease platelet aggregation and inhibit clot formation) was better than monotherapy (use of a single drug treatment) for patients in LAA group, while for patients in CE group, there was no significant difference between the effectiveness of the poly- versus monotherapy. Anticoagulant therapy (treatment using drugs that reduce the body's ability to form blood clots) was associated with better outcomes than antiplatelet monotherapy in the CE group while it was associated with a higher mortality in the SVO group. 

In summary, this study showed that stroke subtype affects prognosis and influences the effectiveness of the secondary prevention method used.

Consult your physician regarding the most effective treatment in your situation.