Depression in epilepsy: Screening is free, easy, crucial

It’s no surprise that people with epilepsy are more likely to suffer from depression. But the reverse is also true to an unusual extent, a conundrum that makes researchers think beyond which came first: Just how tightly are these two conditions intertwined?

For neurologists, these questions are academic for now. Colleagues say it’s more crucial to start determining whether patients are depressed and/or anxious and need treatment. “Up to half of your patients will have depression, and up to half will have anxiety. But almost no one in this session is using a depression screening tool,” said neurologist W. Curt LaFrance Jr., MD, at the 2019 International Epilepsy Congress in Bangkok. Dr. LaFrance is director of neuropsychiatry and behavioral neurology at Rhode Island Hospital, and professor of psychiatry and neurology at Alpert Medical School, Brown University, both in Providence. One free and simple screening tool gets raves: the Neurological Disorders Depression Inventory for Epilepsy (NDDI-E), a six-item questionnaire.

“With a screening tool, we are much more likely to detect depression in our patients, address the issue with them, treat it, and hopefully improve the quality of life of our patients,” said neurologist Joseph S. Kass, MD, JD, of Baylor College of Medicine and Ben Taub General Hospital, both in Houston, who studied the use of the tool in 2009. “If you just rely on the patient to come forward saying,‘I am depressed,’ you will miss many opportunities to help your patient improve his or her quality of life.”

The NDDI-E tool asks patients to look back over the past 2 weeks and describe how often they felt that “everything is a struggle,” “nothing I do is right,” and “I’d be better off dead.” It also asks how often they feel guilty or frustrated and have difficulty finding pleasure. Patients answer the questions with “always or often,” (4 points) “sometimes,” (3 points), “rarely” (2 points) and “never” (1 point).

In a 2006 Lancet Neurology study, the tool’s developers reported that a score greater than 15 points predicts depression with a specificity of 90% and sensitivity of 81%. It was “not affected by adverse effects of antiepileptic medication, whereas models for depression and generic screening instruments were,” the study authors wrote. 

The tool can also be used to detect anxiety.

In 2009, Dr. Kass and colleagues reported in Seizure on their retrospective analysis of 192 consecutive patients who answered the tool’s questions at a seizure clinic at Houston’s Ben Taub General Hospital. Nearly 30% of patients screened positive, and 26% were later determined to indeed have depression. Of those, about two-thirds hadn’t been previously diagnosed or treated.

“A screening questionnaire can be done in the waiting room, saving time in the exam room for those without depression and allowing for more time for those who do have depression,” Dr. Kass said.

Dr. Britton also described another screening test called Response to Immunotherapy in Epilepsy and Encephalopathy (RITE). That test was modified (RITE²) to include additional points for the presence of neural-specific cell surface autoantibodies and an interval of less than 6 months from seizure onset to starting immunotherapy.

The RITE² score is determined by adding the accrued points from the components of APE² plus the presence of a plasma membrane–specific autoantibody and initiation of immunotherapy within 6 months of symptom onset. A RITE² score of 7 or more has 88% sensitivity and 84% specificity of a favorable seizure outcome, defined as at least a 50% reduction in seizure frequency, following initiation of immunotherapy (Epilepsia. 2019 Feb;60[2]:367-369).

What should you do if a patient shows signs of depression? “If neurologists feel comfortable with the use of antidepressants, they can start antidepressant treatment. If they don’t feel comfortable doing that, they can refer for evaluation with a psychiatrist,” said neurologist Andres M. Kanner, MD, of the University of Miami, who helped develop the tool in the 2000s.

If patients don’t want to take additional medications, he said, “then cognitive-behavioral therapy provided by a psychologist can be extremely effective.”

The good news, he said, is that “people with depression and epilepsy respond to lower doses of medication and faster,” compared with the general population. “You’d expect it to be the opposite.”