Suicide-related behaviors in older patients with new anti-epileptic drug use: data from the VA hospital system
1 VA Pittsburgh Healthcare System, Neurology Division, Pittsburgh, PA, USA
2 University of Pittsburgh, Department of Neurology, Pittsburgh, PA, USA
3 Yale University, Department of Psychiatry, New Haven, CT, USA
4 Epilepsy Therapy Project, Orange, CT, USA
5 Veterans Affairs HSR&D: South Texas Veterans Health Care System (VERDICT), San Antonio, TX, USA
6 University of Texas Health Science Center at San Antonio, Department of Psychiatry, San Antonio, TX, USA
7 San Francisco VA Medical Center, San Francisco, CA, USA
8 Division of Geriatrics, University of California, San Francisco, San Francisco, CA, USA
9 Center for Health Quality, Outcomes and Economic Research, Edith Nourse Rogers Memorial Hospital, Bedford, MA, USA
10 Boston University School of Public Health, Boston, MA, USA
11 University of Texas Health Science Center at San Antonio, Department of General Medicine, San Antonio, TX, USA
BMC Medicine 2010, 8:4 doi:10.1186/1741-7015-8-4Published: 11 January 2010
The U.S. Food and Drug Administration (FDA) recently linked antiepileptic drug (AED) exposure to suicide-related behaviors based on meta-analysis of randomized clinical trials. We examined the relationship between suicide-related behaviors and different AEDs in older veterans receiving new AED monotherapy from the Veterans Health Administration (VA), controlling for potential confounders.
VA and Medicare databases were used to identify veterans 66 years and older, who received a) care from the VA between 1999 and 2004, and b) an incident AED (monotherapy) prescription. Previously validated ICD-9-CM codes were used to identify suicidal ideation or behavior (suicide-related behaviors cases), epilepsy, and other conditions previously associated with suicide-related behaviors. Each case was matched to controls based on prior history of suicide-related behaviors, year of AED prescription, and epilepsy status.
The strongest predictor of suicide-related behaviors (N = 64; Controls N = 768) based on conditional logistic regression analysis was affective disorder (depression, anxiety, or post-traumatic stress disorder (PTSD); Odds Ratio 4.42, 95% CI 2.30 to 8.49) diagnosed before AED treatment. Increased suicide-related behaviors were not associated with individual AEDs, including the most commonly prescribed AED in the US - phenytoin.
Our extensive diagnostic and treatment data demonstrated that the strongest predictor of suicide-related behaviors for older patients newly treated with AED monotherapy was a previous diagnosis of affective disorder. Additional, research using a larger sample is needed to clearly determine the risk of suicide-related behaviors among less commonly used AEDs.