Association Between Ozone and Mortality Among Asthma Patients

• Activity Number: 554
• Type: Contributed
• Date/Time: Wednesday, August 12, 2015 : 10:30 AM to 12:20 PM
• Sponsor: Section on Statistics in Epidemiology
• Author(s): Mayada Ali Aljehani* and Mark Ghamsary and Keiji Oda
• Companies: Loma Linda University and Loma Linda University and Loma Linda University
• Keywords: Asthma ; ozone ; GAM ; AHS-2 ; air pollution

Abstract

The present study examined associations between ambient ozone levels at place of residence and mortality among asthma patients. A subgroup of 6,414 Adventists from the Adventist Health Study II in US and Canada 2002-2007 who had not changed residence address since enrollment, reported that they had been diagnosed with asthma. Logistic regression and Generalized Additive Models (GAM) were used to assess the effect of ambient ozone levels on mortality after controlling for gender, age and time spent outdoors. Total mortality was nonlinearly related with ambient ozone levels and age using GAM. However, it was linearly related with gender and outside hours. The quadratic terms for ozone and age are significant, with p-values 0.0006 and 0.03 respectively, however outdoor is marginally significant with p=0.05. Gender is linearly related with mortality with p=0.009. The parametric model revealed that, among persons with asthma, women have 36% lower odds of death compared to men. In addition, ozone was significantly associated with mortality. Age was also associated with increased risk of death (p=0.03) while time spent outside showed a non-significant positive association with mortality.