Living in a city and the risk of Asthma

Living in a city and the risk of Asthma

It is commonly known that asthma prevalence is much higher in cities and other urban environments. This is often due to these environments containing much more pollution than rural areas. There is many other research studies backing this point and an element of logic is applied when associating urban environments with asthma. However a study in the US has proved that this is not always the case.

The study published in the “Journal of Allergy and Clinical Immunology” comes to a different conclusion than previously thought. The study itself involved 23,000 children aged 6-17, whose information was generated by the National Health Interview Survey. When these results were initially observed the researchers found the asthma prevalence was 12.9% in inner-city children and 10.6% in non-inner city areas. This answered the researcher’s initial idea that asthma would be more prevalent in city based areas however when the data was further segmented down into other social and economic factors such as race, geographic areas and sex it provided a different view point. It was discovered that other factors such as poverty or an individual’s racial background were more effective predictors of asthma.

The lead study of the research, Dr. Corinne Keet, assistant professor of paediatrics at John’s Hopkins Children’s centre, was surprised at the findings.

“We didn’t go in looking to make this point at all, we were somewhat surprised to find that living in a city didn’t seem to be a risk factor for asthma”.

This conclusion was previously missed or not researched due to individual cities being analysed instead of whole nationwide data. The original conclusion that pollution in cities causes asthma is still relevant and it is not an issue to be dismissed with the new findings. However the research discovered in this study offers a two part element to asthma prevalence particularly indoor pollution as a cause for concern.

Exposure found in indoors can vary from cleaning supplies, mould pollution and old housing materials. With people now being indoors on average more than outdoors it is no surprise that this type of exposure is potentially causing more asthma issues. There is another factor that must be taken into account such as poverty which potentially relates to the issue of an individual’s living environment causing their asthma.

Senior Author Dr. Elizabeth Matsui commented on their research with the following.

“Our findings suggest that focusing on inner cities as the epicentres of asthma may lead physicians and public health experts to overlook newly emerging ‘hot zones’ with high asthma rates”.

[1] “Study Questions Link between Asthma and City Living”, Alexandra Sifferlin, TIME Online,
[2] “US study finds inner city doesn’t raise asthma risk”, Yahoo News,
[3] “Role of urban living overestimated as asthma risk factor”, James McIntosh, MNT Online,