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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Very warm with sunshine. Chance of thundery showers late morning.
A hot, humid and sunny start before cloud increases as a narrow band of thunderstorms spreads northeast. These clear during the afternoon.
A fine and sunny end to Friday will then be followed by a warm and muggy night. Warm and sunny on Saturday with the risk of a thunderstorm.