Jul 19, 2013

    Memory slips an early sign of dementia?

    FOR years, doctors have dismissed patients' concerns about mild slips of memory as a normal part of ageing. Now, as the focus in Alzheimer's research moves towards early diagnosis, researchers are looking for ways to tell whether some of these "senior moments" are an early sign of the disease.

    The idea is so new that scientists cannot even agree on what to call these memory complaints among people who are still cognitively normal.

    But experts gathered at the Alzheimer's Association International Conference in Boston said evidence is growing that it may be possible to couple certain patterns of memory lapses with genetic markers or changes in the brain and spinal fluid, to better predict which individuals are displaying the earliest symptoms of Alzheimer's.

    Finding people for whom the disease is just beginning to develop is important as companies struggle to find treatments that can prevent or delay the disease.

    In the past 12 months, several high-profile clinical trials testing drugs in people with mild to moderate Alzheimer's failed to show any benefits. Scientists believe that may be because the drugs are being tried too late, when the disease has already killed too many brain cells.

    Last week, Eli Lilly announced that it will start a new clinical trial of its experimental Alzheimer's drug, solanezumab, focusing only on patients with mild signs of the disease, after two late-stage studies of the treatment failed to show any benefits in patients.

    Dr Dean Hartley, director of science initiatives at the Alzheimer's Association, said scientists are just beginning to quantify if anecdotal reports of memory loss have any bearing on whether a person ultimately develops dementia.

    The problem is that many things can cause temporary memory slips, including sleeplessness, depression, stress and some medication.

    "The question is which ones are indicative of underlying pathological changes," he said.

    That doesn't mean that people who occasionally lose their keys or forget where they parked the car should go rushing to their doctor, said Dr Ronald Petersen, an expert in early Alzheimer's disease at the Mayo Clinic in Rochester, Minnesota.

    In a study his team is doing of cognitively healthy people, 80 per cent of normal people aged 70 and older said their memory is not what it once was.

    "What this research is trying to do is carve out that subset of people who are really telling us something that might be important," he said.