State-Level Medical and Absenteeism Costs of Asthma among Children

Rationale: Asthma is a chronic inflammatory condition of the airways characterized by recurrent symptoms of coughing, wheezing, chest tightness, and difficulty breathing. Although asthma affects individuals of all ages, it is the most prevalent chronic disease among children. It has a significant impact on health care use and school attendance resulting in high medical and absenteeism costs of asthma - critical measures of economic impact of the disease. The objective of this study was to estimate prevalence and medical and absenteeism costs of treated asthma among children aged 0-17 for each of 50 states and District of Columbia.

Methods: As a primary source of analysis, we pooled 2008-2012 Medical Expenditure Panel Survey data.  We calculated asthma prevalence as the predicted probability of having asthma using a logistic regression. We used a two-part regression model for annual per-person medical expenditures attributable to asthma. The first part was a logistic regression predicting the probability that a person incurred any medical expenditures, and the second part was a generalized linear model with a gamma distribution and a log link function estimating the total annual medical expenditures for those with positive expenditures. To estimate per-person annual number of missed school days due to asthma we used a negative binomial model.  For each state, we then calculated the total medical expenditures by multiplying the average per person asthma-attributable medical expenditures by payer/age/sex by the number of children with asthma by state/payer/age/sex and aggregating the costs across age/sex categories within each state/payer category. Our methodology accounted for double-counting, which occurs when a person has more than one chronic condition. We assumed that when a child missed a day of school because of asthma, one parent also missed that day from work. Thus, we valued missed school days using parent’s wages.

Results: State-level prevalence of treated asthma among children ranged from 4.6% to 9.1% and was higher among males (ranging from 5.6% to 11%) than females (ranging from 3.6% to 7.1%).  By age, state-level prevalence of treated asthma ranged from 2.9% to 8.1% among children aged 0-4, from 5.5% to 10.6% among children aged 5-14, and from 4.8% to 7.6%.  Average per person annual medical costs of asthma were $880 per person among children aged 0-4, $980 per person among children aged 5-14, and $1,090 per person among children aged 15-17.  Total state-level medical costs of asthma among children ages 0-17 ranged from $6 million to $449 million.  Average annual number of school days missed due to asthma was 2.36 days among children aged 0-4, 2.04 days among children aged 5-14, and 2.43 days among children aged 15-17.  The total number of school days missed among children aged 0-17 in each state ranged from 9,020 to 703,570 days.  The total costs of absenteeism ranged from $1 million to $116 million.

Conclusions: Medical and absenteeism costs of asthma represent a significant economic burden among children. The results of the study emphasize the urgency for state public health programs to further implement sustainable strategies to control asthma.