A new report suggest over a third of dementia diagnoses could potentially be avoided by addressing aspects of one’s lifestyle including exercise, education, blood pressure and hearing.
There were around 45 million people living with dementia in 2015, with recent figures showing this is set to rise; in England and Wales alone it is estimated that there will be a 57% increase in people living with dementia by 2040, with numbers set to hit 1.2million, driven predominantly by people living longer.
But the new report from the Lancet Commission on dementia prevention, intervention and care, stressed that dementia is not an inevitable part of ageing – and that action can be taken to decrease 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.
The authors say the findings highlight the importance of health and behaviour throughout life on the risk of developing dementia later on.
But they admit that the estimate that more than a third of dementia cases could be prevented is a best case scenario, with the figures based on a number of assumptions, including that each factor could be completely tackled. “I think the realistic figure is probably nearer 5%,” said Ballard, although he added that even a 5% reduction would mean 5,000 fewer dementia cases in the UK per year.
The authors also acknowledge that for some of the factors flagged it is not yet clear whether interventions could reduce the risk of dementia or delay its onset. Debate also exists around whether factors such as depression and social isolation drive and increased risk of dementia, or whether changes in the brain that lead to dementia could be behind such issues.
Dr Doug Brown, director of research at Alzheimer’s Society, said that the estimate that more than a third of dementia cases could be preventable was a cause for celebration, but noted that difficulties remain.
“Not all of the nine risk factors identified are easily modifiable – factors like poor education and social isolation are incredibly challenging to address. But there are easier wins, particularly cardiovascular factors like lowering blood pressure and smoking cessation,” he said.
“Though it’s not inevitable, dementia is currently set to be the 21st century’s biggest killer. We all need to be aware of the risks and start making positive lifestyle changes.”Tags: Alzheimer's, dementia, exercise, health, lifestyle