A Stroke is the formation of a blood clot in a blood vessel supplying blood to the brain. Or the rupture of blood vessles
in the brain.

Smoking may cause an artery in the brain to become blocked by a blood clot or other debris carried in the bloodstream. This cuts off the blood supply to the surrounding brain cells and causes them to die.

This can affect thinking, movement, speech and/or the senses. About a third of those who have a stroke die within 12 months, with another third becoming permanently disabled.