08/21/06

Patients with persistent asthma incur high medical costs as well as indirect costs for employers, reports a study in the August Journal of Occupational and Environmental Medicine, official publication of the American College of Occupational and Environmental Medicine (ACOEM).

Led by Gene Colice, MD, of Washington Hospital Center, Washington, DC, the researchers used a large insurance database to analyze costs associated with persistent asthma. Patients were classified as having persistent asthma if they suffered from asthma attacks at least twice weekly (among other criteria). The analysis included nearly 3,000 patients with persistent asthma, including employees and dependents covered by insurance plans at 17 US companies.

Direct medical costs for patients with persistent asthma averaged about $6,500 per year, compared to just more than $2,000 for patients without asthma. Thus, direct costs for a patient with persistent asthma were $4,500 higher than for nonasthma patients.

Data on 443 employees with persistent asthma also showed high indirect costs—costs from disability and missed work days. On average, annual indirect costs were $924 higher for workers with persistent asthma. The differences in direct and indirect costs remained significant after statistical adjustment for other factors.

Further analysis compared costs for workers with mild, moderate, and severe persistent asthma. Costs were highest for patients with severe persistent asthma who have continual asthma symptoms causing significant limitations in physical activity.

Surprisingly, there was no significant difference in costs between patients with moderate persistent asthma, who have asthma attacks at least twice weekly, and those with moderate persistent asthma, who have daily attacks. This probably reflected the low rate of treatment with inhaled steroids—the most effective medications for controlling asthma—by patients in the mild group. Less than 10% of patients with mild persistent asthma used inhaled steroids on a daily basis, compared to 80% or more of those with moderate to severe persistent asthma.