brainscanThe proportion of people aged over 65 in the UK with dementia has fallen in the past 20 years, according to new estimates, but the government has been warned dementia is still a priority to ensure people with the condition receive the care they need.

The study, by the Cambridge Institute of Public Health (CIPH), University of Cambridge, found that there have been marked changes in the older population over the past 20 years, with more people living to ages at which they are expected to be at the highest risk of dementia. However, when applying the prevalence of dementia from 20 years ago, it was expected that 8.3% – 884,000 people – would have the condition, but the study identified a lower prevalence, with only 6.5% of over 65s having dementia – a reduction of nearly a quarter.

CIPH’s study, which is part of the Medical Research Council-funded Cognitive Function and Ageing Studies (CFAS), randomly chose people aged 65 and over living in Cambridgeshire, Newcastle, and Nottingham. The first part of the study, CFAS I, took place between 1989 and 1994, with more than 7,000 people interviewed about lifestyle, health, socioeconomic factors, medication, social care and other factors, with about 1,500 participants also diagnostically assessed to determine whether they had dementia. The second part of the study, CFAS II, used identical methods to survey 7,796 randomly selected people aged 65 and over in the same geographical regions, between 2008 and 2011. 

The data collected in both parts of the study allowed researchers to estimate the prevalence of dementia in people aged 65 and over in 1991 and in 2011.

However, while the over prevalence of dementia is down, it remains considerably higher in women, with 7.7% of women over 65 thought to have dementia, compared to 4.9% of men.

In addition, the prevalence of the condition among people living in residential care homes has increased, from about 56% of residents 20 years ago to 70% today.

“This study provides compelling evidence of a reduction in the prevalence of dementia in the older population over two decades,” said Professor Carol Brayne, of the CIPH, who led the study. “Whether or not these gains for the current older population will be borne out in future generations would seem to depend on whether further improvements in primary prevention and effective healthcare for conditions which increase dementia risk can be achieved.”

Maintain dementia priority

Dr Richard Horton, editor-in-chief of The Lancet, which published the study, said the reduction in prevalence of dementia is an important and welcome finding. “But it is not a signal for the government to deprioritise investment in dementia care and research. Dementia remains a substantial challenge for those affected, their families, the NHS, and the Treasury. We need to understand better why the prevalence of dementia has fallen, and what that means for prevention and treatment services. Sadly, dementia care and research are too often neglected and underfunded in the UK.”

Dr Andrew McCulloch, chief executive of the Mental Health Foundation, welcomed the “surprising but great news”.

He speculated that the fall in prevalence may be partly linked to a decrease in vascular dementia cases as people might be living healthier lifestyles. “This could be through having a more balanced diet, decreasing their alcohol intake or taking more physical activity,” he said.

“It is perhaps also an indication of the general public’s greater awareness of dementia thanks to the work of many organisations, family carers and people with dementia themselves. However, a changing diagnostic criteria may be part of the reason for this decline which might indicate that we are still learning about the condition.

“It’s essential therefore that dementia remains a priority for the government for those who remain affected and there is still a lot of work to do to ensure that they receive the care they need and get a better quality of life.”