Most important risk factors for Alzheimer’s can be modified

The team said that research pointing to soaring rates of dementia was outdated and that the new findings, published today in the journal Lancet Neurology, “present a rather different picture to the so-called dementia epidemic”.

“These old studies support the idea of a continuing “dementia epidemic”, but are now out of date because of changes in life expectancy, living conditions, and improvements in healthcare and lifestyle”, Professor Brayne said.

In an significant revelation, a study has found that the number of people with dementia – both new cases and total numbers with the disease – is stabilising despite population ageing, in direct contrast to the “dementia epidemic” as reported in some recent studies.

The experts looked at data from five large studies in Sweden, the Netherlands, the UK and Spain that compare dementia numbers in old people. The studies done in Stockholm (Sweden) and Rotterdam (the Netherlands) showed that the age-specific incidence of dementia is falling in these regions.

“The evidence put forward to suggest declining prevalence in high-income countries is fairly weak”, said Martin Prince, a professor at King’s College London’s Institute of Psychiatry, Psychology and Neuroscience.

“Measures to help people adopt healthy lifestyles now could have a real impact on the numbers of people living with dementia in the future”. “It is important to remember that the number of people over age 85 is the fastest growing age demographic, with about 40% now estimated to be affected by dementia”, said her Cambridge co-author Yu-Tzu Wu.

Despite the findings, critics have warned that because there is no cure dementia is the most critical health and social care challenge facing the country.

But “it’s vital that we continue to invest in research into preventions, as well as better treatments and improved diagnosis for those cases that can not be prevented”, he stressed.

The research was welcomed by charities which said it proved that simple changes could prevent the condition. “Therefore, we have carried out the most extensive and comprehensive systematic review and meta-analysis to date, which employs a full-scale search of observational studies to calculate effect sizes of various modifiable risk factors for [Alzheimer’s disease]”, researchers from Qingdao University in Qingdao, China, wrote.

Complex roles of pre-existing disease, including frailty, carotid atherosclerosis, hypertension, low diastolic blood pressure and type 2 diabetes among Asian individuals increased risk for Alzheimer’s disease, while history of arthritis, heart disease, metabolic syndrome and cancer decreased risk.

Folic acid, coffee and vitamins C and E were also associated with helping to stave off the disease, along with current smoking (only amongst Western populations), light-to-moderate drinking (one to three alcoholic drinks a day), stress, and high body mass index (BMI) in late life.

“Alzheimer’s disease is likely to be caused by a combination of genetic and lifestyle factors that we don’t yet fully understand”, he added.