Scientists are to explore whether drugs usually used to treat erectile problems by expanding blood vessels could become the next major way to tackle the dementia epidemic. Vascular dementia is often caused by damage to the small blood vessels of the brain leading to reduced blood flow to brain tissue. This blood vessel damage - known as small vessel disease - is seen in the brains of 50-70% of elderly people. The researchers hope that one drug known for it use in treating impotence can prevent the damage that leads to vascular dementia.