More than a third of dementia cases might be avoided by tackling aspects of lifestyle including education, exercise, blood pressure and hearing, a new report suggests.
Approximately 45 million people worldwide were thought to be living with dementia in 2015, at an estimated cost of $818 billion.
But the new report from the Lancet Commission on dementia prevention, intervention and care, stresses that dementia is not an inescapable part of ageing – and that action can be taken to reduce risk.
“There are a lot of things that individuals can do, and there are a lot of things that public health and policy can do, to reduce the numbers of people developing dementia,” said Gill Livingston, professor of psychiatry of older people at University College London and a co-author of the report.
For many of the factors, including exercise and social activities, the best approach to reducing dementia risk is not yet clear, but Livingston stresses that steps can still be taken. “We expect it to be a long-term change that will be needed for exercise; joining a gym for two weeks is probably not going to do it,” she said.
Clive Ballard, professor of age-related diseases at the University of Exeter medical school and also a co-author of the report, added that the evidence suggests individuals should also try to follow a Mediterranean diet, maintain a healthy weight and keep an eye on their blood pressure.
In total, the study looked at nine lifestyle factors linked to an increased risk of dementia.
The results reveal that as many as 35% of dementia cases could, at least in theory, be prevented, with 9% linked to midlife hearing loss, 8% to leaving education before secondary school, 5% to smoking in later life and 4% to later life depression. Social isolation, later life diabetes, midlife high blood pressure, midlife obesity and lack of exercise in later life also contributed to potentially avoidable cases of dementia, the report notes.