Very Small Cerebral Lesions May Increase Risk of Stroke

Magnetic resonance imaging detects very small cerebrovascular lesions, which may be associated with increased risks for stroke and death, according to a study published in the Annals of Internal Medicine.

Researchers from Mississippi, Maryland, Washington, Minnesota, and North Carolina sought to determine stroke risks associated with brain lesions 3 mm or smaller, which are typically ignored by clinicians, and white matter hypersensitivities (WMHs).

A total of 1,884 subjects, aged 50 to 73, with no prior history of stroke, participated in the study. All underwent MRI of the brain. The researchers evaluated:

• Lesion size

• WMH score (scale of 0 to 9)

• Incident stroke

• All-cause mortality

• Stroke-related mortality

Follow-up was an average of 14.5 years.

The results showed that the stroke risk was tripled among patients who had lesions that were 3 mm or smaller, compared with patients who had no lesions seen by MRI. There were:

• 157 clinical strokes (89% were ischemic strokes)

• 50 stroke-related deaths

• 576 all-cause deaths

The researchers concluded that these very small cerebrovascular lesions may be associated with an increased risk of stroke and death, but more study is needed.