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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Commuters heading and out of London faced big delays after a person was struck by a train in Essex.
Outbreaks of mostly light and patchy rain will clear east through the evening.
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