Men who smoke more than 20 cigarettes a day run over twice the risk of a stroke caused by bleeding into the brain.
Around 12 per cent of all strokes are hemorrhagic strokes, caused by bursting of a blood vessel and bleeding into the brain. Around 37 per cent of these strokes are fatal within 30 days.

Research has already pinpointed a clear link between ischemic stroke - caused by a clot in a blood vessel serving the brain - and smoking. New research from Harvard Medical School now associates smoking with hemorrhagic stroke risk as well. The data comes from the Physicians Health Study, which covers 22,022 male US physicians followed for nearly 18 years.

Compared to those who had never smoked, men who smoked less than 20 cigarettes a day had a 1.7 times higher risk of hemorrhagic stroke and in men who smoked more than this, the risk went up to 2.4 times. Former smokers had about the same risk of hemorrhagic stroke as men who had never smoked. Clearly, quitting is beneficial although this study cannot say how fast the risk of stroke diminishes when someone gives up.