Direct and indirect costs associated with epileptic partial onset seizures among the privately insured in the United States.

PURPOSE: Compare annual direct and indirect costs between privately insured U.S. patients with epileptic partial onset seizures (POS) and matched controls.

METHODS: One thousand eight hundred fifty-nine patients (including a subset of 758 employees) with >or=1 (POS) diagnosis (ICD-9-CM: 345.4.x-345.7.x), 1999-2004, ages 16-64 years, were identified from a privately insured claims database. Control group was an age- and gender-matched cohort of randomly chosen beneficiaries without epilepsy (ICD-9-CM: 345.x). All were required to have continuous health coverage during 2004 (baseline) and 2005 (study period). Chi-square tests were used to compare baseline comorbidities. Univariate and multivariate analyses were used for comparisons of annual direct (medical and pharmaceutical) and indirect costs during the study period.

RESULTS: Patients with POS were on average 42 years of age, and 57% were women. Patients with POS had significantly higher rates of mental health disorders, migraine, and other neurologic disorders, and higher Charlson comorbidity index (CCI) compared with controls. On average, direct annual costs were significantly higher for POS patients ($11,276) compared with controls ($4,087), p < 0.001; difference of $7,190. Epilepsy-related costs (i.e., costs for antiepileptic drugs, claims with epilepsy or convulsions diagnoses) accounted for $3,290 (29% of direct costs). Employees with POS had substantial and significantly higher indirect (disability- and medically related absenteeism) costs compared with controls ($3,431 vs. $1,511, p < 0.001). Multivariate analyses supported the matched-control univariate findings.

CONCLUSION: Patients with POS had significantly higher costs compared with matched controls. Epilepsy-related costs underestimate the excess costs of patients with partial onset seizures.