The challenges of assessing effectiveness of lacosamide using electronic medical record databases

Abstract

PurposeElectronic health record (EHR) databases are a potential source for conducting research to generate real world evidence on patient outcomes. The objective of the study was to evaluate the feasibility of using EHR data to assess seizure outcomes in patients treated with lacosamide (LCM) monotherapy. MethodsThis was a retrospective cohort study conducted using the Optum clinical EHR database. The study sample comprised patients ≥17 years of age with epilepsy or seizures and treated with LCM monotherapy between 1 January 2009 and 31 December 2013. Structured and unstructured data from prescribed medication and abstracted physician note records were used to identify patients with epilepsy treated with LCM monotherapy and measure seizure frequency outcomes. The index date was the first date of LCM monotherapy, with a 6-month baseline period. Patients were observed for up to 12 months beginning on the index date (follow-up period). The EHR data were not sufficient to compute days supply and explicit duration of LCM and other antiepileptic drug (AED) therapies; therefore, LCM monotherapy was estimated from prescription dates of AEDs. Outcomes were change in seizures per month or change in seizure frequency category from baseline to follow-up. Descriptive statistics were used to describe baseline characteristics and study outcomes. ResultsA total of 10,988 patients with at least one LCM prescription were identified during the study period, 470 of whom met all the selection criteria and were included in the study sample. Although many patients had abstracted physician note records that referred to their seizures, only 3.2% of the patients had seizure frequency information that could be used to quantify the number of seizures per month in both the baseline and follow-up periods; thus, this information could not be used to assess the effectiveness of LCM monotherapy on seizure outcomes. ConclusionLacosamide monotherapy effectiveness was not estimated because the EHR prescription record data did not have sufficient information on days supply. Additionally, most patients' records did not contain adequate information to allow for evaluation of quantitative changes in seizure frequency based on the number of seizures per month. More studies are needed to validate these study findings.