Over the past 15 years, a large number of medications for the treatment of epileptic seizures have become available in the UK. In that same time period, medical guidelines and common medical practice have evolved, whereby some medications have become less often prescribed, and others more often prescribed. If the addition of new medications to the guidelines has been impactful, one would expect an improvement in overall treatment success of epilepsy. This study will attempt to identify to what extent medical practice (prescribing) has evolved, what the current level of effectiveness of treatment of epilepsy is, and whether this is any different versus 15 years ago.
This will be a descriptive, exploratory cohort study. Broadly, the objective of this study is to assess the evolution of (1) Anti-epileptic drug (AED) prescription patterns and sequencing, and (2) treatment outcomes in real-life clinical practice in England. Patients will be selected with a definite diagnosis of epilepsy between April 1st 2003 and the latest available data, where diagnosis is defined as a diagnosis of epilepsy made by a neurologist in the in- or outpatient setting, as recorded in HES or primary care data. Patients will be categorised as having been diagnosed in one of 3 time periods (eras). Treatment patterns between eras will be explored, as the percentage of patients prescribed a certain AED. For every patient, treatment outcome will be assessed, as remission (absence of seizure codes and new AED attempts), possible misdiagnosis (presence of a differential diagnosis code, cessation of all AED treatment, and absence of further seizure codes), or unclear outcome. Outcome will be analysed using Kaplan-Meier methods, with or without the use of cumulative distribution methods, in cases of competing risks.
Health Outcomes to be Measured:
The following possible outcomes will be defined. The outcomes are mutually exclusive.
1. One-year, 2-year, 5-year remission from seizures (mutually exclusive)
2. Possible misdiagnosis
3. Unclear outcome and untreated at end of follow-up
4. Unclear outcome and treated at end of follow-up
HES Admitted;HES Outpatient