Prevalence of epilepsy/seizures as a comorbidity of neurologic disorders in nursing homes

Abstract

Objective:To determine the prevalence of epilepsy/seizure (epi/sz) comorbid with other neurologic disorders in elderly nursing home residents and to examine demographic and regional variability and associations with clinical characteristics.Methods:We studied 5 cross-sectional cohorts of all residents in any Medicare/Medicaid–certified nursing home in the United States on July 15 of each year from 2003 to 2007. Epi/sz was identified by ICD-9 codes (345.xx or 780.39) or check box (Minimum Data Set). Epi/sz prevalence was stable across all years, so only 2007 data were examined further. Logistic regression with generalized estimating equations was used to model cross-sectional prevalence of epi/sz as a function of demographics and neurologic comorbidities of interest, with adjustment for clinical characteristics, including cognitive status, comorbidity burden, medication burden, and activities of daily living.Results:Point prevalence of epi/sz in 2007 was 7.7% (n = 91,372 of N = 1,186,579) differing by geographical region, race/ethnicity, age group, and sex. Neurologic conditions having the highest association with epi/sz were brain tumor (epi/sz prevalence 23.4%–35.2%), head injury (17.9%), hemiplegia (17.7%), and stroke (13.7%). Epi/sz comorbid with stroke or dementia had a strong decreasing association with age (65–74 years had ≈3.8-times higher odds of epi/sz than 85+ years). Activities of daily living, comorbidity burden, and cognition scores were worse in persons with than without epi/sz.Conclusions:The prevalence of epi/sz in the elderly nursing home population is >7-fold higher compared to community-dwelling elderly and is 7 to 30 times higher among those with certain comorbid neurologic conditions. Demographics and clinical characteristics had weaker associations with epi/sz prevalence.