An Analysis of the Environmental Risk Factors of Childhood Asthma and Asthma-like Symptoms: Results from the National Longitudinal Survey of Children and Youth

• Author / Creator

  Parsons, Marc A

• It is known that a multitude of environmental factors are implicated in the incidence of asthma and asthma symptoms among children; however, previous research has provided inconsistent and/or insufficient evidence as to whether residing in a farming environment during childhood can lead to a reduced asthma risk in future life as predicted by the hygiene hypothesis. Similarly, observational and laboratory studies have shown that the risk of asthma attacks in asthmatic children is related to ambient air pollution exposure in childhood, but the evidence remains ambiguous as to whether air pollution can lead to de novo childhood asthma. In this thesis, individual-level data from the National Longitudinal Study of Children and Youth (NLSCY) were used to examine the relationships between farm residence during childhood and ambient air pollution levels, respectively, with the risk of asthma and asthmatic symptoms. Children resident in farming environments were found to have a significantly lower risk of asthma incidence compared to those residing in non-rural areas in the 14-year follow-up study. Further, higher levels of nitrogen dioxide exposure (NO2) were found to be positively related with an increased 12-month prevalence of asthma attacks in childhood. These findings add to the evidence that farm residence and, to a lesser extent, ambient air pollution exposure is related to childhood asthma and its symptoms. Further research into the biological and genetic mechanisms, which may explain these findings, is needed to better understand the complex relationship between the environment and asthma risk in childhood.

• Subjects / Keywords

  • Air pollution
  • Hygiene hypothesis
  • Asthma
  • Epidemiology

• Graduation date

  Spring 2016

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3VH5CS0J

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.