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.
More top news
Wisbech in Cambridgeshire has been described as one of Britain's most segregated towns. We returned there to gauge reaction to the vote.
ITV News Anglia looks back on a night of drama as the East plays a key role in Britain's exit from the EU.
We look at the implications of the EU referendum result on various aspects of life in Britain.