Causes

Most strokes occur in the second half of life and are caused by damage to blood vessels that has occurred over many years. They may have been damaged by a variety of causes. High blood pressure (hypertension), smoking (smokers have double the risk of stroke as non-smokers), high cholesterol and heavy drinking. The recommended 'safe' limits for alcohol consumption are 21 units each week for women and 28 units each week for men. One unit of alcohol is equivalent to a measure of spirits, a glass of wine or half a pint of beer. People who drink more than this run a higher risk of stroke. Obesity, heart disease and diabetes also lead to an increased risk of stroke. Healthy women on the low dose oral contraceptive pill have a 1.5 times increased risk of stroke due to artery blockage. Overwork or stress may cause raised blood pressure but most strokes are not caused by stress.