Researchers claim to have uncovered potential causes of early-onset dementia.
A team from the Mayo Clinic has stated that the condition is often caused by neurodegenerative or autoimmune/inflammatory conditions, but only rarely by Alzheimer's disease - making its cause markedly different from that of dementia in older individuals.
During the investigation, some 235 patients aged between 17 and 45 who had previously had normal cognitive function were tested.
It emerged that in a third of participants dementia was caused by neurodegenerative disorders such as frontotemporal dementia, Huntington's disease or familial prion disease and a further 20 per cent suffered from dementia as a result of autoimmune or inflammatory conditions such as multiple sclerosis.
Dr Brendan Kelley, who led the research, stated that understanding what causes early-onset dementia could be useful in assessing what is the most effective treatment for the condition, although more research is needed.
According to the Alzheimer's Society, there are currently 15,000 younger people with dementia in the UK.
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