Small Silent Strokes Increase Risks

Undetected strokes increase risk of dementia

(RxWiki News) Small undetected strokes are not uncommon in older patients. These incidences may be contributing to an increased risk of dementia and Alzheimer's disease in such patients.

The finding is of concern because 65 percent of stroke patients experience difficulty with thinking, memory, goal setting and motivation after a stroke, while up to 30 percent become clinically demented within three months following a stroke.

"Monitor your cholesterol and blood pressure regularly."

Dr. Sandra Black, director of the Brain Sciences Research Program at Sunnybrook Research Institute at the University of Toronto, noted that recent imaging studies on the brains of patients over the age of 65 have shown that 95 percent have brain small vessel disease, which appears as white spots and patches on MRI images. Small vessel disease generally develops after small undiagnosed strokes.

As many as 25 percent of healthy seniors over the age of 70 show evidence of small silent strokes, while about 14 percent of patients with an average age of 60 experience such small strokes, according to preliminary results of the Canadian PURE MIND study

Dr. Black said that Alzheimer's and small vessel disease often live together in the brains of the elderly in a way that can be very disabling. Though there is no cure for either disease, she urged action to delay the onset or progression. For example she said regular aerobic exercise throughout a person's lifetime can delay the onset of later life dementia, especially in those more genetically prone to developing dementia.

She emphasized that stroke and Alzheimer's disease share the same vascular risk factors including high blood pressure, obesity, diabetes, smoking, high cholesterol and a sedentary lifestyle. Reducing those risk factors aids patients in lowering their risk of stroke and dementia.

"It turns out protecting the blood vessels in your heart and body also helps to protect your brain and its blood vessels. This can delay the onset of dementia," said Dr. Black.

The preliminary research, which has not yet been published, was recently presented at the Canadian Stroke Congress.

Review Date: 
October 4, 2011