• Posted September 11, 2023

City Living Means More Coughs, Colds for Kids

Two new studies looked to explain an increased risk of respiratory infections like coughs and colds in babies and young children, finding city living to be among the culprits.

Young children who grow up in towns and cities instead of the countryside suffer more respiratory infections, according to research presented Monday at a meeting of the European Respiratory Society, in Milan, Italy. Findings presented at medical meetings are considered preliminary until published in a peer-reviewed journal.

A second study that was also presented at the event and published Sept. 11 in the journal Pediatric Pulmonology, found that attending day care, living in a damp home or residing near dense traffic increased young children's risk of chest infections. That study also noted that breastfeeding reduced the risk.

In the first study, researchers included more than 660 children and their mothers. Participation began during pregnancy and continued until the children were 3 years old.

By age 3, kids living in urban areas averaged 17 respiratory infections, such as coughs and colds, compared to 15 for kids in rural areas.

That research also included detailed blood tests of the pregnant women and their newborns. Researchers analyzed the infants' immune systems at 4 weeks of age and found differences between the urban and rural babies.

There were also differences in blood samples from moms and babies related to living environments and number of respiratory infections.

"Our findings suggest that urban living is an independent risk factor for developing infections in early life when taking account of several related factors such as exposure to air pollution and starting day care,"said Dr. Nicklas Brustad, a researcher and physician based at Gentofte Hospital and the University of Copenhagen, Denmark.

"Interestingly, changes in the blood of pregnant mothers and newborn babies, as well as changes in the newborn immune system, seem to partly explain this relationship," he said in a meeting news release.

Brustad, who will present this study, said the results suggest that a child's living environment can affect their developing immune system before they are exposed to coughs and colds.

"We continue to investigate why some otherwise healthy children are more prone to infections than others and what the implications are for later health,"Brustad said. "We have several other studies planned that will look for risk factors and try to explain the underlying mechanisms using our large amount of data."

The second study included data on more than 1,300 mothers and children in Scotland and England. When kids were 1 and 2 years of age, mothers completed detailed questionnaires about chest infections, symptoms such as coughing and wheezing, respiratory medication and exposure to potential environmental risk factors.

An analysis of the questionnaires revealed that breastfeeding for longer than six months helped protect youngsters from infections. Attending day care increased the risk.

Kids living in damp homes were twice as likely to need an inhaler to relieve respiratory symptoms and to need treatment with a steroid inhaler.

Living in an area with dense traffic increased the risk of chest infections, the study found. Exposure to tobacco smoke increased the risk of coughing and wheezing.

"This research provides some important evidence about how we can help reduce chest infections in babies and toddlers,"said Dr. Tom Ruffles, of Brighton and Sussex Medical School and University Hospitals Sussex NHS Foundation Trust in England.

"The benefits of breastfeeding are well-established, and we should continue to support mothers who want to breastfeed their babies," he said in the release. "We should also be making every effort to reduce exposure to infections in day care, keep homes free of damp and mold, reduce tobacco smoking and cut air pollution."

Ruffles' colleague, co-author Dr. Somnath Mukhopadhyay, said urgent action is needed to tackle the problems of mold and dampness in social housing. He advocates pushing laws to compel landlords to fix mold and dampness issues in their properties quickly.

More information

St. Louis Children's Hospital has more on colds and upper respiratory infections.

SOURCE: European Respiratory Society International Congress, news release, Sept. 11, 2023