The antiepileptic drugs carbamazepine and lamotrigine were associated with a lower risk for first-appearance psychiatric symptoms and disorders than other drugs in the same class, according to the findings of a study published in Epilepsy & Behavior.
Psychiatric disorders are common in people with epilepsy, with approximately 23% reporting depression, and people with epilepsy have a 2.2-fold higher risk for suicidal thoughts compared with the general population. As the adverse effects of antiepileptic drugs can also influence a patient’s quality of life, the authors designed their study to compare individual intervention options for the patients who rely on them.
Using the Health Improvement Network database, the authors identified 9595 drug-naive patients with incident epilepsy, 77% of whom had received a first prescription of an antiepileptic monotherapy between 2000 and 2012. Prescription trends varied over the years, with valproate use declining significantly among women and lamotrigine and levetiracetam becoming more popular with time for all patients. The median age of patients receiving a first prescription from this drug class was 48 years; patients diagnosed at an earlier age were less likely to receive medication.
The results indicated hazard ratios of 0.84 and 0.83 for carbamazepine and lamotrigine, respectively, when it came to first-recorded psychiatric symptoms following a diagnosis of epilepsy. Carbamazepine, in particular, was associated with lower hazards for depression and anxiety in secondary analyses.
None of the antiepileptic drugs examined appeared to reduce or increase the risk for suicide.
Other patient characteristics were associated with a higher risk for a first depressive symptom or disorder following the use of antiepileptic drugs, including female sex, higher Charlson comorbidity index score, or history of other psychiatric diagnosis or treatment.
One limitation of the study was its inability to account for epilepsy severity. Because psychiatric disorders are more prevalent in individuals with medication-resistant epilepsy, and those with more severe epilepsy are more likely to be prescribed antiepileptic drugs, it is possible the findings were skewed by selection bias.
Nonetheless, the authors stated that their findings were “generalizable to most high-income countries,” and that they may be useful in clinical practice.
Josephson CB, Engbers JDT, Jette N, et al. Prescription trends and psychiatric symptoms following first receipt of one of seven common antiepileptic drugs in general practice. Epilepsy Behav. 2018;84:49-55.