Half of global cases of dementia could be prevented or stalled by lifestyle changes including more exercise, says the Alzheimer’s Society. Kath Hudson reports

Untreated vision loss and bad cholesterol have been cited in new research as high risk factors for dementia, according to a Lancet Commission study, part-funded by the Alzheimer’s Society.

The updated Lancet Commission study on dementia prevention, completed in Q2 2024, added untreated vision loss in later life and high low-density lipoprotein cholesterol (bad cholesterol) in mid-life as risk factors for developing the condition. They contribute to 2 per cent and 7 per cent of cases respectively. The report says that eliminating all the addressable risk factors could theoretically halve the number of dementia cases.

As well as having far-reaching benefits for so many individuals – the number of people living with dementia is forecast to treble to almost 153 million by 2050 – addressing the risk factors and reducing the number of people living with the illness would bring down the global costs linked to dementia, which now exceeds £780 billion a year.

Fiona Carragher, chief policy and research officer at the Alzheimer’s Society says: “Dementia is a global crisis affecting more than 55 million people and the UK’s biggest killer, but it’s never too early or too late to reduce dementia risk.

“This Lancet Commission study suggests that nearly half of dementia cases around the world could be delayed or prevented,” she said. “If we can support people to reduce their dementia risk and address the societal change needed, this could mean hundreds of thousands fewer people will develop dementia.”

Understanding risk factors
Some risk factors can’t be changed. Age is the biggest, with the over 75s most at risk. There’s also a genetic risk and more women than men live with dementia. This could be because they live longer and it might be impacted by women over 80 having had less opportunities for education and work when they were younger.

Some risk factors need to be addressed on a societal level, including social isolation, education inequalities and air pollution. People who live in deprived areas are at a higher risk, which might be because of the lack of opportunities to keep mentally active; less access to health and social care and higher levels of air pollution. Small particles from traffic fumes and burning wood in the home have also been identified as risk factors.

Access to healthcare is important to help with other risk factors, including hearing and vision loss and head injuries. The Lancet commission has made a number of recommendations including making hearing aids available for people with hearing loss, providing children with good-quality education, being cognitively active in midlife and detecting and treating high cholesterol from the age of 40.

The risks that are controllable by the individual are taking more exercise, stopping smoking and stopping excessive alcohol consumption.

More: www.hcmmag.com/dementia