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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Early fog will clear to leave a dry day with sunny spells and highs of 18 deg C (64 deg F)
Overnight there'll be mist and fog but it will clear for Sunday leaving sunny spells.
A month of special events for the Norfolk nurse responsible for saving Allied soldiers in the First World war, has begun.