Aug. 4, 2010 -- Drugs used by epilepsy patients to control seizures now carry a warning that the medications may increase the risk for suicide, but a newly published analysis involving more than 5 million people finds no evidence of such a risk.
The study is the latest to challenge a 2008 research review by the FDA that linked many commonly prescribed epilepsy drugs to an increase in suicidal thoughts and behaviors.
Suicide Risk Higher in Epilepsy Patients
As previously reported, patients with any of the three conditions had a higher risk for suicide, compared to the general population.
But no increase in risk associated with treatment was seen among patients with a diagnosis of epilepsy alone.
The research appears in the Aug. 5 issue of the New England Journal of Medicine.
Massachusetts-based drugmaker Sepracor Inc. funded the study. The company is seeking FDA approval for its seizure drug Stedesa.
“Even in patients with epilepsy and depression, the risk was low,” lead researcher Alejandro Arana, MD, of the drug safety research group Pharmacovigilance Services, tells WebMD. “We did not find any increase in risk associated with use of anti-epileptic drugs by patients with epilepsy.”
Unlike many previous studies, the researchers were able to individually assess risk among different groups of patients treated with seizure drugs, including those with epilepsy, depression, or bipolar disorder alone and patients with epilepsy and depression or epilepsy and bipolar disorder.
Certain seizure drugs are used for the treatment of depression and bipolar disorder, in addition to epilepsy.
Neurologist and epilepsy researcher Josemir W. Sander, MD, of the University College London, says the assessment of risk in different subtypes of patients is a major strength of the study.
Specific Drugs Not Examined
An increase in suicide risk associated with treatment was found in patients with depression alone and in patients with an unknown diagnosis without epilepsy, depression, or bipolar disorder.
Researchers were not able to assess risk associated with specific seizure medications. Several recently reported studies have been contradictory.
In late July, researchers in Germany reported a threefold increased risk of suicidal behavior and self-harm in epilepsy patients taking the drugs Keppra, Topamax, and Sabril.
Sanders says the new findings should reassure patients with epilepsy who take seizure drugs.
He adds that although there will probably never be a definitive study to prove or disprove the association between seizure drugs and suicide, the risks associated with poorly controlled epilepsy are well known.
“Epilepsy can kill,” he tells WebMD. “It is not uncommon for people to die because they have a seizure in the wrong place at the wrong time, such as when they are driving a car. It is important for people to stay on these drugs if they need them.”