Reducing air pollution may help elderly people to live independent lives for longer, research has found.
Dr Boya Zhang, of the University of Michigan, who is one of the authors of the study, said: “Air pollution is linked to worse health – more lung disease, more heart disease, shorter life expectancies and more likelihood of dementia. Knowing that air pollution increases our risk of poor health as we age made us wonder if exposures might also impact how people can care for themselves in later life.”
The researchers started by looking at the lives of 25,314 older people in the US from 1996 to 2016. Each person was living independently when they were enrolled in the study and was interviewed every two years. After an average of nine years, 40% of subjects needed help at home because of health or memory problems, or had had to move into a care home.
The change from being independent to needing care was linked with local air pollution levels during the previous 10 years, especially in those over 75 years old. This relationship was strongest for particle pollution from transport and for nitrogen dioxide.
The researchers estimated that 730,000 people a year in the US lose their ability to live independently due to traffic pollution. This was approximately 15% of the total number of people who lost their independence, at an annual cost of $11.7bn (£9bn).
Dr Sara Adar, who led the study, said: “Our results provide evidence that the damage done to our bodies by air pollution may alter how well we are able to care for ourselves as older adults. Taking action on air pollution will not only enhance the quality of life for older adults but also reduce the healthcare burdens on society.”
She added: “This research supports the recent lowering of the US national ambient air quality standard for particulate matter. It also suggests that exposure to traffic-related pollution may be particularly important for health as we age.”
While the US study focused on outdoor air pollution, researchers in China have focused on air pollution inside people’s homes. They found that switching from clean fuels to solid fuel led to an increased risk of needing care. Compared with people who used clean energy sources, those burning solid fuel had a 40% increased need for physical care such as help bathing and dressing. They were also 70% more likely to need help with other things such as shopping, managing money and medication.
