Researchers at the Royal College of Surgeons in Ireland say they have developed a new blood test for early stage Alzheimer's disease.

It is hoped the tool could help with the earlier diagnosis of patients, which in turn could improve their quality of life.

The test analyses the changes in concentration of a small molecule called microRNA in the blood and can enable diagnosis even when symptoms are mild.

It is also capable of distinguishing Alzheimer's from other brain diseases with similar symptoms and of predicting how the disease will develop.

The discovery is important as up to 25,000 people in Ireland have Alzheimer's, and as the population here and globally ages, the number of cases is expected to rise significantly.

Researchers are currently trying to develop many new therapies for the neurodegenerative disease.

However new affordable and minimally invasive diagnostic methods are also needed so that large groups of people can be tested for it.

The research is being carried out by scientists and clinicians from Ireland and Spain, and is one of a number presented by early stage researchers at the Royal College of Surgeons in Ireland Research Day.

Other studies showcased include a way to diagnose lung cancer in a patient's breath and a potential new treatment to target an under-studied form of breast cancer.