Alzheimer’s disease is not one illness but has three distinct types

    18 September 2015

    Alzheimer’s disease consists of three distinct subtypes, according to a study carried out by researchers at the University of California in Los Angeles and published in the journal Aging.

    The researchers say their findings could lead to more targeted treatments being developed.

    It was discovered that one subtype in particular is a ‘fundamentally different condition’ from the other two. Dr Dale Bredesen, the study’s lead author, says this will help the development of personalised treatments in the future.

    ‘Because the presentation varies from person to person, there has been suspicion for years that Alzheimer’s represents more than one illness. When laboratory tests go beyond the usual tests, we find these three distinct subtypes.

    ‘The important implications of this are that the optimal treatment may be different for each group, there may be different causes, and, for future clinical trials, it may be helpful to study specific groups separately.’

    The three subtypes are inflammatory, non-inflammatory and cortical.

    Cortical Alzheimer’s typically affects younger people, and affects a larger area of the brain. The first symptom of the condition isn’t memory loss, but the loss of language skills. Because sufferers generally don’t have the ‘Alzheimer’s gene’ it is often misdiagnosed.

    Bredesen says the next step in his research is to find out if there are different underlying causes behind the subtypes, and whether or not optimised treatments would be appropriate.