Analysis of Short-term Influences of Ambient Aeroallergens on Pediatric Asthma Hospital Visits in the Cincinnati Area

• Activity Number: 74
• Type: Contributed
• Date/Time: Sunday, August 7, 2005 : 8:00 PM to 9:50 PM
• Sponsor: Section on Statistics and the Environment
• Author(s): Wei Zhong*+ and Linda Levin and Atin Adhikari and Tiina Reponen and Rakesh Shukla and Gurjit K. Khurana Hershey and Grace LeMasters
• Companies: University of Cincinnati and University of Cincinnati and University of Cincinnati and University of Cincinnati and University of Cincinnati and Cincinnati Children's Hospital Medical Center and University of Cincinnati
• Keywords: ambient aeroallergens ; pediatric asthma hospital visit ; generalized linear model ; generalized additive model

Abstract

The objective of our study is to investigate the association between daily pediatric asthma hospital visits and daily concentrations of aeroallergens and their specific species. Records of daily asthma visits are retrieved from Cincinnati Children's Hospital Medical Center and aeroallergen sampling is performed by the Button Inhalable Sampler. The Poisson generalized linear model controlling for confounders is applied: A restricted cubic splines of time term is used to filter out the seasonal variation and time trends in asthma visits, day-of-the-week indicators are employed to model the visit variation during the week, and weather variables are treated categorically to take out the asthma dependence on weather. Sensitivity of the aeroallergen regression coefficients to the ways confounders are modeled is investigated by repeating the analysis using a generalized additive model, where counts of daily asthma visits are fitted to nonparametric smoothing splines of time and weather parameters. Aeroallergens with significant impact on asthma hospital visits are ragweed, oak/maple, pinus, and Alternaria. The effects in causing the asthma exacerbation are delayed by 3 or 5 days.