3099 Risk of substance abuse onset in adults diagnosed with epilepsy or migraine

OBJECTIVES/SPECIFIC AIMS: The study investigated whether adults diagnosed with epilepsy or migraine (a neurological disorder with common features to epilepsy) are at increased risk for developing substance abuse disorders following diagnosis compared to (presumably healthy) adults with lower extremity fracture (LEF). METHODS/STUDY POPULATION: A retrospective cohort analysis was conducted using a subset of surveillance data of hospital admissions, emergency department visits and outpatient visits in South Carolina, USA from January 1, 2000 through December 31, 2011. Individuals aged 18 years or older were identified using the International Classification of Disease, 9(th) Revision Clinical modification (ICD-9) with a diagnosis of epilepsy (epilepsy-cohort 1; n = 78,547; 52.7% female, mean age [SD] 51.3 years [19.2]), migraine (migraine-cohort 2; n = 121,155; 81.5% female, mean age [SD] 40.0 years [14.5]), or LEF (control cohort; n = 73,911; 55.4% female, mean age [SD] 48.7 years [18.7]). Individuals with substance abuse or dependence diagnosis following epilepsy, migraine, or LEF were identified with ICD-9 codes. Cox proportional hazard regression analyses modelled the time to substance abuse diagnosis comparing epilepsy to LEF and comparing migraine to LEF. RESULTS/ANTICIPATED RESULTS: Adjusting for insurance payer, age and sex, adults with epilepsy are diagnosed with substance abuse disorders at 2.5 times the rate of those with LEF [HR 2.54 (2.43, 2.67)] and adults with migraine are diagnosed with substance abuse disorders at 1.10 times the rate of those with LEF [HR 1.10 (1.04, 1.16)]. An interaction between exposure and insurance payer was found with hazard ratios comparing epilepsy to LEF of 4.56, 3.60, and 1.94 within the commercial payer, uninsured and Medicaid strata, respectively. DISCUSSION/SIGNIFICANCE OF IMPACT: Compared to adults with LEF, adults with epilepsy had a substantially higher hazard of subsequent substance abuse, while adults with migraine showed a small, but still significant, increased hazard of subsequent substance abuse.