Ageing and the city: Chronic diseases more prevalent in city-dwellers than country counterparts

Ageing Australian city-dwellers are more likely to suffer from non-infectious chronic diseases such as type 2 diabetes, arthritis, cancer and asthma than their rural counterparts, according to new research from the University of Sydney.

29 sept 2012--The research, conducted by academics from the University's Faculty of Health Sciences and published in this month's edition of the Australasian Journal of Ageing, tracked seven years of longitudinal data for 1256 over-45s who had lived in the same area for at least 20 years.

Results showed people living in urban areas had greater odds of having from a non-infectious chronic disease than people in rural and remote areas.

Every year of age increased the odds of having a long-term health condition by 1.05, or five percent compared with the previous year, while living in the lowest socioeconomic area increased the odds of having a long-term health condition by 90 percent.

"In the city you're exposed to a range of environmental stressors, such as poor air quality, aircraft and road noise, high density housing, lack of adequate transport, poor urban design, a lack of green spaces and shade trees, and so on," says lead author Professor Deborah Black, from the University's Ageing, Work and Health Research Unit.

Lower socioeconomic status was associated with a higher prevalence of non-infectious chronic disease because cheaper housing was generally located in areas with high levels of environmental stressors, such as industrial areas, airports or busy roads.

"As people get older, their bodies are less able to cope physiologically with environmental stressors, and exposure can accelerate the ageing process and trigger or exacerbate disease," Professor Black says.

"With 85 percent of Australians living in the city and 22 percent of Australians estimated to be 65 or older by 2026, it's crucial that we update policy, urban design and primary care in line with the realities of our population."

The research responds to a pressing need to better understand the problems faced by Australia's increasingly urban, ageing population. While the link between urbanisation and population health is well established, until now there has been very little research on the interaction between age and urban living.

According to Professor Black, climate change is one of the most critical issues for the health of ageing Australians.

"In cities, the lack of trees and green spaces create what's called the heat island effect, wherein the sun heats exposed urban surfaces such as roads, roofs, and pavements to temperatures up to 50 degrees Celsius hotter than the air temperature," she says.

"Because older people are less able to cope with high temperatures, they are more at risk of climate change-related health problems than the rest of the population. Effective thermoregulation and hydration are particularly difficult for older people in hot weather, which can lead to problems with heart and kidney function, medication management and falls.

"We also find that because an ageing population is not as mobile, they don't have the opportunity to get away from the environmental stressors around their home and community."

Provided by University of Sydney