Fears of an Alzheimer’s explosion are unfounded, according to new research showing that dementia rates may be stabilising in the UK and other parts of Europe.
Scientists found that the proportion of British people aged 65 and above with dementia fell by more than a fifth in 2011 compared with what it was predicted to be a decade earlier.
Studies in other European countries show a similar trend. In Zaragoza, Spain, there was a 43 per cent fall in the prevalence of dementia in men aged 65 and older between 1987 and 1996, and dementia incidence had also declined in Sweden and the Netherlands.
Experts pointed out that much of the evidence pointing to a dementia “epidemic” was based on outdated research started in the 1980s.
Since then, improvements in living conditions, health care and lifestyle had altered the picture.
Lead researcher Carol Brayne, from the Institute of Public Health at Cambridge University, said: “The suggested decrease in dementia occurrence coincides with improvements in protective factors, such as education and living conditions, for dementia and a general reduction in risk factors, such as vascular diseases, over recent decades.
“Incidence and deaths from major cardiovascular diseases have decreased in high-income countries since the 1980s. We are now potentially seeing the results of improvements in prevention and treatment of key cardiovascular risk factors such as high blood pressure and cholesterol reflected in the risk of developing dementia.”
An estimated 850,000 people in the UK are affected by dementia, more than 60 per cent of whom have Alzheimer’s disease. In Malta, more than 4,500 individuals have dementia, a figure that is expected to double by the next 25 years.
The authors of the new evidence review, published in The Lancet Neurology journal, point out that even if rates of the condition stabilise, the care of sufferers will remain a major challenge in years to come.
Yu-Tzu Wu, another member of the Cambridge team, said: “It is important to remember that the number of people over age 85 is the fastest growing age demographic, with about 40 per cent of these currently estimated to be affected by dementia.”
Matthew Norton, head of policy at the charity Alzheimer’s Research UK, said: “We still need greater public awareness of the risk factors for dementia, and policymakers as well as charities have a key role to play in improving people’s understanding of what they can do to potentially reduce their risk.”
Jeremy Hughes, chief executive of the Alzheimer’s Society, said: “With no cure, few effective treatments and an economic impact exceeding that of cancer or heart disease, dementia remains the most critical health and social care challenge facing the UK.”
Elizabeth Coulthard, consultant senior lecturer in dementia neurology at the University of Bristol, said the evidence suggested that previous predictions of dementia prevalence had been “somewhat overblown”.
She added: “It is possible that factors such as nutrition and living conditions contribute to the stabilising prevalence. Nevertheless, the impact of dementia is still huge affecting around seven per cent of people over 65 and 40 per cent of those over 80. So while this is positive news, it should not detract from the great efforts to develop treatments that may delay progression of dementia and improve quality of life for those affected by the disease.”