Abstracts

Rationale: Epilepsy is a chronic disorder with a prevalence between 0.5% and 1% and substantial economic burden related to both direct medical costs and lost or reduced earnings and productivity. There is a paucity of data from population screening studies that evaluate comorbidities and their impact in the epilepsy population. Methods: The National Comorbidity Survey Replication is a nationally representative, face-to-face U.S. household survey of 9282 respondents ≥18 years of age, conducted in 2001-2003. Respondents were selected from a multistage area probability sample of the non-institutionalized civilian population in the 48 contiguous states; response rate was 70.9 %. The study sample comprised all respondents who screened positive for any mental disorder (n = 4235) plus a probability sample of the remaining respondents (n = 1457). The presence of epilepsy or seizures was ascertained by self-reported response to a question on a chronic condition checklist (“Did a doctor or other health professional ever tell you that you had epilepsy or seizures?”). Mental disorders were ascertained with the Composite International Diagnostic Interview (version 3) that collected diagnostic criteria according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition. Separate logistic regression models were used to estimate the association between epilepsy or seizures and selected mental disorders and chronic physical conditions controlling for demographics. Results: The weighted prevalence of self-reported epilepsy or seizures in the study sample was 1.82%, with no statistically significant relationship to gender, age, race, or education; those with epilepsy or seizures were over twice as likely (OR=2.4; 95% CI 1.4-4.2) to have never married and almost 4 times as likely (OR=3.8, 95% CI 2.2-6.6) to be unemployed or disabled. The weighted prevalence of all chronic physical conditions examined, except cancer, was higher in those with epilepsy or seizures (vs. without): arthritis, headache, asthma, stroke and sensory impairments reached statistical significance (p<0.05). In addition, 68% of those with epilepsy or seizures were found to have a mental disorder in their lifetime (OR=2.1; 95% CI 1.2-3.7) and those with epilepsy or seizures were more likely to have panic disorder (OR=1.9; 95% CI 1.0-3.6), post-traumatic stress disorder (OR=2.0; 95% CI 1.2-3.3), conduct disorder (OR=3.3; 95% CI 1.5-7.3), or drug abuse (OR=1.8; 95% CI 1.0-3.4). Conclusions: These findings suggest that many mental disorders and chronic physical conditions were more likely to occur in those with epilepsy or seizures than in those without. Further research using larger population samples is needed to explore these relationships more fully.