MAYO CLINIC -- Migraine headaches can knock you down, and keep you there. Those who suffer from migraine headaches often say they can feel them coming on.

One of those early indicators is migraine aura, visual disturbances that set in before the headache.

There's information from the Mayo Clinic that shows that migraine sufferers who also get auras may be at a higher risk of stroke and cardiovascular disease. The risk is even higher if you smoke, or are a woman on birth control. More information on this report can be found on the Mayo Clinic's Web site.