221574 Analysis of spirometry benefits in children with asthma using propensity score matching

Wednesday, November 10, 2010 : 11:05 AM - 11:20 AM

Tursynbek Nurmagambetov, PhD, MS, MA , Senior Science Fellow at Air Pollution and Respiratory Health Branch, Centers for Disease Control and Prevention, Atlanta, GA
Shubhayu Saha, PhD , Air Pollution and Respiratory Health Branch, Centers for Disease Control and Prevention, Atlanta, GA
OBJECTIVES: To assess the benefits of spirometry for children with asthma using propensity score method. METHODS: A retrospective cohort study of children with asthma aged 5-18 was conducted with 2005-2007 MarketScan data. The main outcome was the number of hospitalizations or ER visits for asthma (acute asthma events) in 2007. We used propensity score matching (PSM) to control for confounding between the groups with and without spirometry tests. Four PSM strategies were used: one nearest neighbor (0.02), five nearest neighbors (0.02), local regression and kernel matching (0.8). An exposed group was defined as children who had at least one spirometry test in 2005-2006. A separate unexposed group without spirometry was generated based on one of four PSM strategies. RESULTS: Children with spirometry had similar demographic, geographic, health status and plan type characteristics to those without; however children with a spirometry test had more asthma medications, specialist visits and acute asthma events (AAEs) compared to children without spirometry. The average number of AAEs in 2007 in the exposed group was 0.105, while that number was 0.117, 0.119, 0.115 and 0.112 in the unexposed groups, as previously defined. Thus without adjustment children with spirometry had about 25% more AAEs than did children without spirometry. After PSM adjustment having spirometry was associated with 6-11% fewer AAEs depending on the PSM strategies used, suggesting that this correction is likely due to PSM adjustments for possible confounding effect. CONCLUSIONS: Children with asthma who had spirometry tests had significantly fewer AAEs, suggesting important benefits of spirometry in pediatric care.

Learning Areas:
Biostatistics, economics
Chronic disease management and prevention
Public health or related public policy
Public health or related research
Social and behavioral sciences

Learning Objectives:
Demonstrate benefits of spirometry in children with asthma based on the analysis of retrospective health insurance claim data by a use of propensity score matching method.

Keywords: Asthma, Pediatrics

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: I lead a team of health economists at the CDC National asthma program
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.

Back to: 5104.0: Asthma epidemiology