Duke 2008 | ASHE | Equity and Efficiency in Health and Healthcare

Purpose: This paper estimates the extra costs and health service utilization in children with asthma. It will analyze Tennessee hospital inpatient and outpatient discharge records for 2003-05 to compare the costs and service utilization of pediatric patients with and without asthma as a primary or secondary diagnosis.

Background: Asthma is the most common chronic disorder in childhood, currently affecting an estimated 6.2 million children under 18 years of age. According to the CDC, the estimated cost of treating asthma in those under 18 is $3.2 billion per year and asthma is the third-ranking cause of hospitalization among children under 15. In 2004, asthma accounted for an estimated 14 million lost school days in children. It is the leading cause of school absenteeism attributed to chronic conditions.

Hypotheses: We will test three hypotheses. The first is that in both the inpatient and outpatient settings, the per capita costs are higher among children 2-17 years of age who have an asthma diagnosis than those who do not. The second hypothesis is that children in the asthma group are more likely to have a 'potentially avoidable hospitalization' or a 'non-urgent' ED visit than those who do not have a diagnosis of asthma. A third hypothesis is that African American children are disproportionately represented among children with asthma whose inpatient admissions and outpatient ED visits are potentially avoidable or non-urgent.

Data Sources: The primary source is the Hospital Inpatient Discharge Data System (HDDS) maintained by the Tennessee Department of Health. HDDS receives information from the federal UB-92 forms on all inpatient and outpatient discharges in Tennessee. Each form contains information on patient diagnoses, procedures performed, charges, and selected patient demographics. We will analyze patients who had an outpatient encounter or inpatient admission at a general medical-surgical hospital or a pediatric hospital in Tennessee.

Methodology: Patients ages 2-17 will be divided into two groups: those with asthma and a control group of patients without asthma. The asthma group comprises pediatric patients with at least one diagnosis of asthma (ICD-9 code 493.xx) as the primary diagnosis or one of the secondary diagnoses. The control group includes all pediatric patients without a diagnosis of asthma. We will use the definition of ambulatory care sensitive conditions in the Pediatric Quality Indicators of AHRQ (http://www.qualityindicators.ahrq.gov/pdi_overview.htm) to identify potentially avoidable admissions, and the Non-Urgent ED Visits Algorithm developed by the New York University (http://wagner.nyu.edu/chpsr/?p=4) to identify non-urgent ED visits. Appropriate statistical techniques such as descriptive analysis, general least squares and logistic regression will be used for testing the hypotheses.

Potential Contribution: Previous studies of pediatric asthma have focused on the direct costs of hospitalizations and outpatient encounters in children who sought treatment for asthma. They therefore ignored a large group of children who had asthma but entered the hospital for a non-asthma condition. This study contributes to the understanding of the costs of pediatric asthma by documenting the extra utilization of inpatient and outpatient services and the resulting additional costs when the sick child has asthma as either a primary or secondary diagnosis.