A
silent stroke is a
stroke that does not have any outward
symptoms associated with stroke, and the patient is typically unaware they have suffered a stroke. Despite not causing identifiable symptoms a silent stroke still causes damage to the brain, and places the patient at increased risk for both
transient ischemic attack and major stroke in the future. In a broad study in 1998, more than 11 million people were estimated to have experienced a stroke in the United States. Approximately 770,000 of these strokes were symptomatic and 11 million were first-ever silent MRI infarcts or
hemorrhages. Silent strokes typically cause
lesions which are detected via the use of neuroimaging such as
MRI. The risk of silent stroke increases with age but may also affect younger adults. Women appear to be at increased risk for silent stroke, with
hypertension and current
cigarette smoking being amongst the predisposing factors.