Risk of readmission for injury in patients with epilepsy in the United States – A population-based study

Objective: The objective of this study was to determine the 30-day injury readmission risk among persons with epilepsy vs. without epilepsy using a nationally representative US database. Secondary objectives were to examine the factors associated with injury-related readmissions among those with epilepsy and identify specific causes of readmissions within 30 days of index admission. Methods: Hospitalized individuals of all ages with epilepsy as the primary diagnosis were identified using validated International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes in the 2014 Nationwide Readmission Database (NRD). Primary outcome was 30-day readmission for an injury defined by ICD-9-CM diagnosis codes following discharge from index hospitalization. Subgroup differences in the groups with epilepsy and without epilepsy were estimated using standardized mean difference scores that are calculated with means and variances of the covariates. Multinomial logistic regressions were conducted to determine the 30-day injury readmission risk and examine the factors associated with injury-related readmissions. Results: There were 60,074 unique persons with epilepsy (mean age: 42.53 years, female: 49.32%) and 9,282,952 without epilepsy (mean age: 44.46 years, female: 59.43%). A higher proportion of persons with epilepsy (n = 215, 0.34%) vs. without epilepsy (n = 22,783, 0.22%) had a 30-day readmission due to an injury. After adjusting for covariates, persons with epilepsy had higher odds of 30-day readmission due to an injury (adjusted OR: 1.40, 95% CI: 1.20–1.62, p < 0.0001). Factors associated with an injury-related readmission in persons with epilepsy include the following: increasing age (OR: 1.01, 95% CI: 1.00–1.02, p = 0.02), transfer to short term hospital/other facility (OR: 1.50, 95% CI: 1.00–2.27, p = 0.05), discharged against medical advice/discharge destination unknown (OR: 2.26, 95% CI: 1.40–4.45, p = 0.02), and higher Elixhauser comorbidity index (OR: 1.02, 95% CI: 1.01–1.03, p < 0.0001). Conclusions: Higher odds of 30-day injury readmissions were observed in persons with epilepsy vs. without epilepsy. Optimizing the management of comorbid conditions during the patient's index admission for epilepsy, minimizing discharges against medical advice, and fostering outreach programs to those who have been transferred to short-term hospitals or facilities may reduce 30-day readmissions due to an injury.