It's thought as many as 50,000 people may be living with dementia in the East - but haven't been diagnosed.
The statistics obtained by the Alzheimer's Society found doctors in some areas are spotting only a third of cases.
It means patients are missing out on the vital support they need.
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Cloudy with more rain. This rain will become increasingly heavy and persistent during the early hours to give a wet start to Sunday
Ice hockey rivals from Peterborough and Milton Keynes prepare for their local derby match with an unusual challenge away from the rink.
Today will be mostly cloudy and mild with occasional rain, more persistent overnight