The burden of adult asthma in the United States: Evidence from the Medical Expenditure Panel Survey

Background It is important to have an accurate picture of the sources and extent of medical expenditures and productivity loss to understand the nature and scope of the burden of asthma in the United States (US). Objective The current study aims to provide recent nationally representative estimates of direct and productivity-related costs attributable to asthma in adults in the US. Methods The 2003 and 2005 Medical Expenditure Panel Surveys were used to estimate the effect of asthma on medical expenditures, use, productivity, and chronic comorbidity among adults (≥18 years). Productivity-related outcome variables included employment, annual wages, missed work days, days spent sick in bed, and activity limitations. Multivariate regression was conducted, controlling for sociodemographics and comorbidity. Results Of 47,033 adults, 2,003 reported asthma. Compared with those without, subjects with asthma were significantly less likely to be employed (odds ratio, 0.78), spent 1.4 more days sick in bed annually, and were significantly more likely to have activity limitations or to be unable to work. Adults with asthma incurred an additional $1,907 (2008 US dollars) annually and experienced higher health care use and comorbidity. The total national medical expenditure attributable to adult asthma was $18 billion. Adults with asthma were more likely to be covered by Medicaid (30%) than the general adult population (10%). The largest contributors to medical expenditures for adults with asthma were prescription drugs, followed by inpatient hospitalizations and home health care. Conclusions In recent national data adult asthma is associated with a significant deleterious effect on direct and indirect costs in the US.