WASHINGTON, D.C.: A simple memory test costing a few cents can give up to two years’ warning of the full onset of Alzheimer’s disease, a landmark study has found.
Scientists believe they could use it to catch patients at a “sweet spot”, where there is time to stave off the symptoms of dementia.
Although there are no drugs to treat Alzheimer’s, two clinical trials have shown promising early results and are expected to conclude next year. If they succeed, dementia experts predict the first drugs could be prescribed within a decade. One of the biggest problems is that the disease is usually diagnosed at an advanced stage, when it is much harder for doctors to manage brain damage.
Researchers have found a cheap spatial memory test invented in Britain a decade ago can reliably diagnose Alzheimer’s and give months or even years of warning before dementia becomes evident. Early data suggest it is 93 per cent accurate.
Dennis Chan, a clinical neuroscience lecturer at the University of Cambridge, said there was an urgent need for a way of screening the millions of middle-aged people who went to their GPs with mild cognitive impairment.
Memory tests for dementia used in doctors’ surgeries are no more predictive than a flip of a coin, although some specialist clinics achieve better results. The other options in Britain’s National Health Service are a lumbar puncture, which involves draining and analysing a sample of spinal fluid, or a brain scan.
Known as the Four Mountains test, the new method involves showing patients a picture of a mountain landscape and asking them to identify it among a selection of four landscapes, one of which is the same one seen from a different angle. In a study of 15 patients with mild cognitive impairment, the test identified those in whom Alzheimer’s was diagnosed over two years with as much accuracy as the surgical technique, and more than double for conventional memory tests.
The test is available as an iPad app that costs £40 ($80). Spread over the hundreds of patients in a GP practice, it would cost a few cents a time.
“The caveat is that we have only proven the principle and the real test is in the work being done now,” Dr Chan said. The group will publish its findings this year and Dr Chan will speak about the test at next month’s Cambridge Science Festival.