City residents are 1.12 times more likely to develop the serious brain disorder compared to their regional counterparts, a university study has found.

The study published in PLOS One used the latest available data from the Survey of Disability, Ageing and Carers (SDAC), a nationally representative database collected by the Australian Bureau of Statistics (ABS) about the health of people in Australia.

The University of Southern Queensland study is the first to establish a link between dementia risk and geographic remoteness from an Australian perspective. The study also explores the recent changes in dementia prevalence.

It found dementia rates across the population increased from 0.84% to 0.89% between 2015 and 2018.

For people living in major cities, the prevalence was 5,590 per 100,000 in 2018 – an 11% increase from 2015. Conversely, there was a 21% decrease in dementia rates among people living in outer regional and remote areas during the same period.

Dementia is a significant health problem among older Australians, with one in 20 people aged over 65 nationally having dementia. 

Researcher, PhD student Rezwanul Haque said the study highlighted the increasing health threat and that without a breakthrough, the number of Australians with dementia is expected to more than double by 2058, according to the Australian Institute of Health and Welfare.

“There is currently no cure for any form of dementia,” he said.

“Australia’s ageing population is expected to grow even older in the coming decades, which will drive up dementia rates even more and put more pressure on families, health care systems and communities.”

Diabetes, high blood pressure, obesity, undernutrition, depression, and brain injuries have increased over time in Australia, which may all be a factor in the rise in dementia rates.

However, Mr Haque’s supervisor and co-author Professor Khorshed Alam said environmental factors could be the reason why people in major cities are at greater risk of developing dementia.

“Earlier research identified chronic noise exposure, air pollution and a paucity of green space as probable risk factors for cognition reduction, which are more prevalent in metropolitan areas,” he said.

Professor Alam said policymakers should take note of the findings to come up with solutions to deal with the disease.

“Green spaces and increasing the number of urban trees could lower dementia risk by encouraging physical activity, social interaction, and network building while simultaneously reducing exposure to air pollution,” he said.

“Councils could develop standalone urban forest strategies or integrate the conservation of urban forests into municipal strategic planning statements to ensure that residents and communities have healthier environments.

“Additionally, state and territory governments could provide additional funding for vital services such as memory clinics, geriatric assessments and home visits for older adults, services for older adults’ mental health, hospital-to-residential aged care transition services, and assistance for those who are exhibiting behavioural and psychological signs of dementia.” 

The study can be found here.