New figures from the Alzheimer's Society show that, in some parts of the East Midlands, just four in ten people with dementia are being diagnosed with the condition.
The charity says it's disappointing that the number of cases being spotted varies so greatly between different parts of the region.
Our correspondent Peter Bearne has been talking to one woman who says health professionals repeatedly refused to accept her elderly mother had the disease.
More top news
Cloudy and breezy tonight with rain. Drier tomorrow.
Turning cloudy and becoming windier later. Patchy rain overnight.
James Bond's favourite car brand, the Aston Martin, has launched its latest model at its Warwickshire factory - the DB11.