Individuals who develop drug-resistant epilepsy within a year after initial diagnosis have higher burden of mental and physical diseases one-year prior to epilepsy diagnosis as compared to those whose seizures were controlled during the same interval.

Abstract Introduction Epilepsy is a neurological disease characterized by recurrent, unprovoked seizures and its impact on biological, cognitive, psychological, and social outcomes. An unmet need for finding effective treatment options exists. Identifying medical diagnoses present prior to a diagnosis of epilepsy is an important step in increasing our understanding of how people with epilepsy may respond to therapy, help guide clinicians in managing associated comorbid conditions, and inform future research. Methods A population-based retrospective comparative cohort study was conducted using administrative claims data to explore differences in medical diagnoses prior to an initial diagnosis of epilepsy between patients with and without drug-resistant epilepsy (DRE) identified within one-year post diagnosis by evaluating standardized mean differences between the groups. Results A total of 205,183 patients with newly diagnosed epilepsy were identified. Of those, 4.1% (n = 8340) were considered drug resistant one-year post diagnosis. Pain and mood disorders were the common physical and psychiatric diagnoses in both cohorts. Differences between the newly diagnosed epilepsy and DRE cohorts were observed. Patients in the DRE cohort were younger, had more encounters with the healthcare system, and higher burden of disease for both physical (e.g., headache, neuropathy, muscular-skeletal disorders, and traumatic brain injury) and psychiatric diagnoses (e.g., depression, anxiety, bipolar disorder, suicidal thoughts, drug dependency, and sleep disorders). Conclusion Physical and psychiatric diagnoses are common one year prior to first diagnosis of epilepsy in administrative claims data. Compared to patients without DRE, those who develop DRE within one-year post initial diagnosis demonstrated a higher burden of disease.