London: Millions could be saved from developing Alzheimer's by making a few simple changes to their lifestyle, such as exercising more and quitting smoking, a new research suggests.
A third of Alzheimer's disease cases worldwide can be attributed to risk factors that can be potentially modified, such as lack of education and physical inactivity, researchers said.
Current estimates suggest that by 2050, more than 106 million people will be living with
Alzheimer's disease, a huge increase on the 30 million people affected by the disease in 2010, researchers said.
Alzheimer's disease is caused by a complex interplay of genetic and lifestyle factors. Amongst the greatest lifestyle factors are lack of exercise, smoking, poor educational attainment and depression, all of which can be targeted to reduce the risk.
A study published in 2011 suggested that as many as one in two cases of Alzheimer's could potentially be prevented by modifying lifestyle factors.
However, this study treated the risk factors as being independent of one another.
In the new study, led by Professor Carol Brayne from the Cambridge Institute of Public Health at the University of Cambridge and involving co-authors from the 2011 study, this estimate has been lowered to one in three cases.
The seven key risk factors for which there is consistent evidence of an association with the disease are diabetes, midlife hypertension, midlife obesity, physical inactivity, depression, smoking, and low educational attainment.
The researchers estimate that by reducing the relative risk from each of these risk factors by 10 per cent, it will be possible to reduce the prevalence of Alzheimer's in 2050 by 8.5 per cent, preventing 9 million cases.
"It's important that we have as accurate an estimate of the projected prevalence of Alzheimer's as possible, as well as accurate estimates of the potential impact of lifestyle changes at a societal level," Dr Deborah Barnes from the University of California, San Francisco and the San Francisco VA Medical Center, who led the 2011 study and is a co-author on this new study, said.
"Alzheimer's disease is placing an ever increasing burden on health services worldwide as well as on both patients and their carers.
"Our hope is that these estimates will help public health professionals and health policy makers design effective strategies to prevent and manage this disease," said Barnes.
The research was published in The Lancet Neurology.