How many people are currently thought to have dementia?
The Department of Health currently estimates around 800,000 people are living with dementia in the UK – or about 670,000 people in England. This includes people who have already been diagnosed and those without a diagnosis.
What is changing?
NHS England is changing the estimated prevalence from April. Under the current calculation, 7.1% of people aged 65 years and over are estimated to have the disease. But from April, the official estimated prevalence for this age group will be 6.5%.
Taking into account that around 95% of people with dementia are in the 65-and-over age group, this would put the new estimate for the number of people with dementia in England at around 617,000.
What is NHS England’s target?
NHS England is aiming for two-thirds of all people with dementia to be diagnosed.
What does all this mean for diagnosis rates?
Latest QOF data to the end of January showed 371,244 people were registered as having dementia in England – or about 55% of the 670,000 people thought to have the disease.
But using the revised figure of 617,000 would mean 60% have already been diagnosed – an increase of five percentage points automatically for average practices.
Of course, by April there could be considerably more people on the register, partly as a result of the controversial dementia diagnosis DES. If latest trends continue, the number of people diagnosed could be about 390,000, giving a diagnosis rate of 63% according to the new prevalence estimate.
This is not far off the 67% diagnosis rate target set by NHS England.
Why is this figure changing?
The current 7.1% figure is based on estimates of dementia prevalence agreed by the Delphi consensus expert group in the Dementia UK report from 2007, taking into account the Cognitive Function and Ageing Study I (CFASI) report published in 1991 which put the prevalence in England at 8.3%.
However, the CFASII report published in 2013 found the prevalence of dementia in people aged 65 and over was 6.5%, reflecting a fall in the incidence of dementia that experts believe could be down to improvements in the management of vascular risk factors and higher levels of education.
Somewhat surprisingly, an updated Dementia UK report published in 2014 ignored the updated figure and continued to estimate 7.1% of people aged 65 and over have dementia.
It is only now that NHS England has confirmed it will switch to applying the 6.5% rate established in CFAS II from April, at least for those aged 65 and over, as this represents the ‘best science’ for use in planning care for England.
