Bolder government action is needed to address inequalities in dementia risk, says Alzheimer’s Research UK

Research presented today (Tuesday 2 August) at the 2022 Alzheimer’s Association International Conference (AAIC) in San Diego links socioeconomic deprivation, including neighbourhood disadvantages and persistent low wages, to higher dementia risk, lower cognitive performance and faster memory decline.

The findings, from four separate studies, also show that people who experience high socioeconomic deprivation are significantly more likely to develop dementia compared to people who live in more affluent areas.

Dr Susan Mitchell, Head of Policy at Alzheimer’s Research UK, said:

“Addressing health inequalities is a key part of the challenge of tackling dementia. These findings add to the growing body of evidence that the environment people live and work in affects their dementia risk, which government plays a key role in helping to shape. “There has never been a more pressing need to identify, understand and develop interventions against risk factors for dementia. Of the leading causes of death, dementia is the fastest rising health condition facing the UK, with numbers set to increase to over 1.6 million by 2050. “By adopting ambitious population-wide measures, the government can improve the environments that people live in, and which in turn enables people from all backgrounds to make positive lifestyle changes to support their brain health and reduce their risk of developing dementia. This effort must involve government departments beyond those responsible for health – for example housing, communities and education – and be backed with sufficient funding. “We urge government to make dementia prevention a key priority in its aim to level up healthcare across the country, and hope the forthcoming health disparities white paper lays the foundation for a fairer, healthier nation.”

In this large-scale study, researchers at the University of Luxembourg examined data from 196,368 participants’ records – including brain scans – from the UK Biobank. All included participants had also had their genetic risk for developing dementia assessed.

Researchers investigated the effect of ‘individual’ socioeconomic deprivation — such as low income — and ‘area-level’ socioeconomic deprivation — such as employment rates — to participants’ risk of developing dementia, and compared it with their genetic risk of the condition.

They found that both individual and area-level socioeconomic deprivation were linked to an increased dementia risk. For people with moderate or high genetic risk, greater area-level deprivation was associated with an even higher risk for developing dementia.

Analysing data from brain scans, they found that both forms of socioeconomic deprivation were also linked to a higher incidence of ‘white-matter lesions’ – an indication of brain ageing and damage.

Dr Susan Mitchell, Head of Policy at Alzheimer’s Research UK, said:

“These findings are a stark reminder of the health gap between the most and least deprived in society, with the most deprived at a higher risk of developing dementia. “Ultimately, these inequalities are profoundly unfair, but they are also avoidable. The government has a key role in addressing inequalities through a range of measures to improve poverty, employment, housing and education. Furthermore there are steps people can take to boost their brain health and reduce the risk of dementia, including staying physically, socially and mentally active, which also need government support to ensure everyone can adopt these changes. “Further research into the social determinants of brain health, including socioeconomic status, will be vital for helping government bring in effective public health policies that help everyone reduce their risk of dementia.”

In a second study, researchers at the University of Texas Southwestern examined perceptions of neighbourhood physical environments and socioeconomic status, alongside a measure of thinking and memory in 3,858 individuals from the Dallas Heart Study.

They found that lower-quality neighbourhood resources, poorer access to food, heating and medical care, and exposure to violence were associated with lower scores on cognitive tests among Black and Latino individuals, compared to White participants.

Dr Susan Mitchell, Head of Policy at Alzheimer’s Research UK, said:

“The impact of socioeconomic status on cognition in Black and Latino populations is particularly worrying, as we know that historically, dementia has often been misunderstood and highly stigmatised by many in in these communities. “Studies like this are good for highlighting links between people’s environment and their health, but this research didn’t look at whether people went on to develop dementia. As diseases like Alzheimer’s develop in the brain over many years, larger studies with a longer follow-up are needed to determine whether these changes are linked to dementia.”

In this study, researchers at Columbia University Irving Medical Center looked to determine whether the socioeconomic status of people’s parents could protect against the impact of higher levels of a protein called ptau-181 in their blood. The protein is used in research as a marker of brain ageing and Alzheimer’s disease.

Socioeconomic status was measured by the number of years people spent in education. The researchers found that in people with higher blood levels of ptau-181, having parents with a higher socioeconomic status was linked to a slower rate of decline in memory, language and executive function as they got older.

Dr Susan Mitchell, Head of Policy at Alzheimer’s Research UK, said:

“These findings indicate that the conditions we grow up in may influence our brains’ ability to withstand the damage caused by Alzheimer’s disease. More research must be conducted to understand the exact mechanisms behind this link, to help inform policies that could help to reduce dementia risk.

“No matter what your age, it is never too early or too late for action to reduce your risk of dementia. Only a third of people in the UK are aware they can reduce their dementia risk – we need government action to help change that and promote the benefits of looking after our brain health.”

To study whether earning low hourly wages over a long period of time is linked to memory decline, researchers at Columbia University School of Public Health used data from a long-term national study of American adults in midlife, and examined the relationship between their employment and memory decline over 12 years.

Compared with workers who never earned low wages, sustained low-wage earners experienced significantly faster memory decline in older age. They experienced approximately one excess year of cognitive ageing per 10-year period.