I've written before about the importance of being able to recognize the signs of stroke. But what if your parent -- or you -- had a stroke and never even noticed?

In a report published in the latest issue of Stroke: Journal of the American Heart Association, researchers found that almost 11 percent of seemingly healthy, middle-aged study participants had some brain damage from one or more "silent" strokes. The researchers also found a correlation between silent stroke and cardiovascular risk factors, such as high blood pressure, atrial fibrillation, and thickening or partial blockage of the carotid arteries.

Also known as silent cerebral infarction, a silent stroke is a true stroke that causes actual brain injury without any noticeable symptoms. People who've had a silent stroke have a higher risk of having more strokes, and are more likely to suffer from vascular dementia later in life.

This finding may sound ominous, but the study's authors point out the good news: Early detection and treatment of cardiovascular risk factors can decrease the risk of stroke. Besides those mentioned above, risk factors that can be controlled include smoking, diabetes, and heart disease.

Personally, I'll be adding this to my growing list of reasons to take better care of my own heart. And maybe I'll send my parents a link to this blog post for good measure.

Image by Flickr user wheat-in-your-hair used under the Creative Commons attribution license.