Obesity identified as a risk factor for Alzheimer's
One 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.
This estimate is lower than the previous estimate of one in two cases, as it takes into account the fact that some of the risk factors used in previous studies are related. For example, three of the risk factors (diabetes, hypertension and obesity) are linked with physical inactivity and all of these are related to educational level.
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.
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 latest study, published in the Lancet and led by Professor Carol Brayne from the Cambridge Institute of Public Health at the University of Cambridge, 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 Alzheimer's Society of Ireland said there are approximately 48,000 people living with dementia in Ireland.
The researchers estimate that by reducing the relative risk from each of these risk factors by 10pc, it will be possible to reduce the prevalence of Alzheimer's in 2050 by 8.5pc, preventing 9 million cases.
Signs and symptoms of Alzheimer's disease include:
• Confusion and disorientation
• Personality changes, such as becoming aggressive, demanding and suspicious of others
• Hallucinations (seeing things that are not there) and delusions (believing things that are untrue)
• Problems with language and speech
• Problems moving around without assistance.
For more information on the condition, visit the website of the Alzheimer's Society of Ireland: www.alzheimer.ie
Health & Living