Excessive drinking, exposure to air pollution and head injuries all increase dementia risk, experts say in a report revealing that up to 40% of dementia cases worldwide could be delayed or prevented by addressing 12 such lifestyle factors.

Around 50 million people around the world live with dementia, and although a dearth of studies and data in Africa makes it difficult to determine the prevalence of the condition on the continent, “recent studies…suggest that dementia prevalence rates in sub-Saharan Africa, in fact, parallel data from Western countries,” a different study asserts.

There is currently no cure for dementia, and, while some risk factors for this condition cannot be changed – for example, particular genes or ethnicity- many are down to lifestyle choices.

“Dementia is potentially preventable – you can do things to reduce your risk of dementia, whatever stage of life you are at,” said Gill Livingston, professor of psychiatry of older people at University College London and a co-author of the report. She added such lifestyle changes could reduce the chances of developing dementia in both those with and without a high genetic risk for such conditions.

The report from the Lancet Commission on dementia prevention, intervention and care builds on previous work revealing that about a third of dementia cases could be prevented by addressing nine lifestyle factors, including midlife hearing loss, depression, less childhood education and smoking.

The research weighs up the latest evidence, largely from high-income countries, supporting the addition of a further three risk factors to the list. It suggests that 1% of dementia cases worldwide are attributable to excessive mid-life alcohol intake, 3% to mid-life head injuries and 2% a result of exposure to air pollution in older age – although they caution that the latter could be an underestimate.

While some actions can be taken on a personal level to tackle such issues, many require government-led change, Livingston said. The report includes a list of nine recommendations, including improving air quality, and urges policymakers to “be ambitious about prevention”.

The impact of lifestyle interventions, the team adds, is likely to be greatest among the most deprived individuals and in low- and middle-income countries. “I don’t think it is any coincidence that the reductions in dementia prevalence to date have been in high-income, highly educated people who have more control over their environment,” said Livingston. “We are expecting by 2050 that two-thirds of people with dementia – if trajectories continue- will be in low-income countries.”

Source: The Guardian