Healthcare Utilization and Expenditure Associated with Newly Diagnosed Epilepsy among Seniors of Arizona Medicaid Beneficiaries

Abstract

Purposes: The purpose of this study was to estimate the incidence rate of epilepsy in 2009 among various patient populations of Arizona seniors enrolled in Medicaid. Additionally, this study aimed to assess the incremental and relative economic and healthcare resource burden of new-onset epilepsy compared with those without newly diagnosed epilepsy. Methods: Arizona Medicaid claims data years 2008 through 2010 were used for this analysis. Patients who were at least 65 years of age as of January 1, 2009 and were continuously enrolled in any coverage group pertaining to Arizona Medicaid for at least 12 months during 2008 and 2009 were considered eligible for the 2009 cohort; patients who were continuously enrolled during 2008 but not at all during 2009 were excluded. In addition to meeting the criteria for the 2009 cohort, incident cases of 2009 must also have epilepsy-related healthcare claims, a one-year clean period during which they cannot have any epilepsy-related healthcare claim, and that their first epilepsy-related healthcare claim in 2009 cannot have with a diagnosis code of 345.x1. The outcome variables assessed included incidence rate of being diagnosed with epilepsy, total monthly healthcare costs, total monthly inpatient costs, total monthly outpatient costs, total monthly prescription costs, incidence rate of inpatient stay, and incidence rate of physician visits. Results: The incidence rate of epilepsy in 2009 for this population was 7.9 per 1,000. Patients with epilepsy-related disease-based risk factors and of younger age had significantly greater incidence rate compared with their counterparts. In general, total monthly healthcare costs and incidence rate of inpatient stay were approximately three times greater in patients with newly diagnosed epilepsy compared with their counterpart (p < 0.001); incremental total monthly healthcare costs in patients with newly diagnosed epilepsy reached 2,077 US dollars. Conclusion: The Arizona Medicaid population appeared to have higher incidence rate compared with the US Medicare and the general US population. Additionally, Arizona Medicaid beneficiaries with newly diagnosed epilepsy had significantly greater healthcare costs and resource utilization compared with those without epilepsy.