In 1 year your risk of having a heart attack will have dropped by half.
In 5 years your risk of having a stroke returns to that of a non-smoker.
In 10 years your risk of lung cancer will have returned to that of a non-smoker.
In 15 years your risk of heart attack will have returned to that of a non-smoker.
In 100 years or less you are dead anyway.