WASHINGTON – Three commonly prescribed antiepileptic drugs – gabapentin, levetiracetam, and topiramate – were associated with greater risk of aseptic meningitis than was lamotrigine in a large cohort of new users of antiepileptic drugs.
Although a black box warning regarding the risk of aseptic meningitis was added to lamotrigine in 2010, no such warning is included for these three antiepileptic drugs (AEDs); the findings of this retrospective study have important implications for weighing treatment options in patients with seizures, Alexis Parente reported at the annual meeting of the American Epilepsy Society.
Among 719,749 AED users, including 60,011 children, the hazard ratios for aseptic meningitis were 1.80, 10.22, and 2.65, respectively, for gabapentin, levetiracetam, and topiramate, compared with lamotrigine, said Ms. Parente of Inovalon, Washington.
The median time to development of aseptic meningitis during a follow-up time of up to 12 months was shorter for children, compared with adults (44 days vs. 77 days), and for patients treated with levetiracetam, compared with those treated with lamotrigine (29.5 days vs. 83 days, respectively). There was no difference in time to aseptic meningitis between gabapentin and topiramate, compared with lamotrigine.
The study cohort included patients aged 2 years and older from a large, nationally representative administrative claims database who began taking an AED between 2006 and 2011. The patients were Medicaid-, Medicare-, and privately insured patients who were continuously enrolled with both medical and pharmacy benefits for at least a year prior to the index AED monotherapy prescription was filled. They did not use any other AED in the 90 days prior to the index prescription.
The findings are important, because long-term adherence to AEDs is a critical factor for the successful treatment of epilepsy, psychotic disorders, and pain, and ideal AEDs should have both high potency and tolerability over the long-term, Ms. Parente said. While some small studies have suggested that some second-generation AEDs may be safer than lamotrigine, she noted, their comparative risks have remained largely unclear.
Adverse effects are the leading cause of treatment failures and are associated with up to 25% of treatment discontinuations in these patients, leading to decreased quality of life and increased health care costs, she added.