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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Sleet and snow overnight in some parts of the Anglia region leading to some settled snow. Wintry showers on Saturday.
Leaders Northampton face Harlequins at English rugby HQ
Cloudy skies with a southeasterly breeze picking up and rain reaching western counties by dusk, perhaps snow in places later.