Alzheimer's blood test 'could be available in two years'

A new blood test based on 10 "biomarker" proteins will make it possible to test new treatments at an early stage of Alzheimer's progression.

Writing in the journal Alzheimer's & Dementia, researchers from King's College London describe how they investigated 26 proteins previously associated with Alzheimer's disease.

They analysed blood samples from 476 confirmed Alzheimer's patients, 220 individuals with "mild cognitive impairment" (MCI) who experienced occasional memory loss, and 450 healthy elderly people.

In the vast majority of cases, memory lapses do not lead to Alzheimer's. But the researchers identified 10 blood proteins that appeared in 87% of MCI patients diagnosed with the disease within a year.

A blood test that can predict the onset of Alzheimer's disease before recognisable symptoms appear could become available in two years, scientists have said.

The test, likely to cost £100 - £300, can show with almost 90% accuracy which individuals suffering from mild memory loss are going to develop Alzheimer's within a year, researchers suggest.

Trials of drugs to halt or reverse Alzheimer's have all ended in failure so far. Therapies exist that can reduce its symptoms, but they only work for a short period of time and are not very effective.

Scientists believe a major reason for the lack of progress is that trial patients are being recruited too late, when their disease is already far advanced.