Economic burden of epilepsy among the privately insured in the US.

Background: The direct cost burden of epilepsy in the US from a third-party payer perspective has not been evaluated. Furthermore, no study has quantified the indirect (work-loss) cost burden of epilepsy from an employer perspective in the US.

Objective: To assess the annual direct costs for privately insured US patients diagnosed with epilepsy, and indirect costs for a subset of employees from an employer perspective.

Methods: A retrospective analysis of a claims database for the privately insured, including employee disability claims from 1999 through 2005 and comprising 17 US companies, was conducted. A total of 4323 patients aged 16-64 years (including 1886 employees) with at least one epilepsy diagnosis (International Classification of Diseases, 9th edition, Clinical Modification [ICD-9-CM] code 345.x) over the period 1999-2004 were included. The control group was a demographically matched cohort of randomly chosen beneficiaries without an epilepsy diagnosis. All had continuous health coverage during 2004 (baseline) and 2005 (study period). Main outcome measures included annual direct (medical and pharmaceutical) costs and, for employees, indirect (disability and medically related absenteeism) and total costs for the study period. Wilcoxon rank-sum tests were used for univariate comparisons of annual direct costs, indirect costs (costs for the subset of employees with these data), and total (direct and indirect) costs during the study period. Two-part multivariate models that adjusted for patient characteristics were also used to compare costs between the study and control groups.

Results: Patients with epilepsy were an average age of 43 years and 57% were female. They had more co-morbidities than controls. On average, direct annual costs were significantly higher per patient with epilepsy than per control ($US10 258 vs $US3862, respectively; p < 0.0001) [year 2005 values], with an annual per-patient difference of $US6396. Epilepsy-related costs ($US2057) accounted for 20% of direct costs for patients with epilepsy. Annual indirect costs were significantly higher for employees with epilepsy than for employed controls ($US3192 vs $US1242, respectively; p < 0.0001), with a difference of $US1950. Total direct plus indirect costs for employees with epilepsy were also higher than those for employed controls ($US13 595 vs $US5338, respectively; p < 0.0001), with a difference of $US8257.

Conclusions: Epilepsy was associated with significant economic burden. The excess direct costs in patients with epilepsy are underestimated when only epilepsy-related costs are considered.