Seizures and mood disorders such as depression may share the same genetic cause in some people with epilepsy, a new study suggests.
The findings may lead to better screening and treatment to improve patients’ quality of life, researchers say.
People have suspected a relationship between epilepsy and mood disorders for millennia.
Scientists studied dozens of families with multiple relatives who have epilepsy, and compared the family members’ lifetime prevalence of mood disorders with that of the US population.
They found an increased incidence of mood disorders in people who suffer from a type of the condition called focal epilepsy, in which seizures begin in just one part of the brain. The researchers did not, however, observe an increase in mood disorders in people with generalized epilepsy, in which seizures start on both sides of the brain.
“Mood disorders such as depression are under-recognized and undertreated in people with epilepsy,” says Gary A. Heiman, associate professor of genetics at Rutgers University–New Brunswick.
“Clinicians need to screen for mood disorders in people with epilepsy, particularly focal epilepsy, and clinicians should treat the depression in addition to the epilepsy. That will improve patients’ quality of life,” Heiman says.
The results of the study—which appear in Epilepsia—support the hypothesis that people with focal epilepsy, but not generalized epilepsy, are susceptible to mood disorders such as depression.
“More research is needed to identify specific genes that raise risk for both epilepsy and mood disorders,” Heiman says. “It’s important to understand the relationship between the two different disorders.”
People have suspected a relationship between epilepsy and mood disorders for millennia, Heiman notes. Hippocrates, the “father of medicine,” wrote about it around 400 BCE: “Melancholics ordinarily become epileptics, and epileptics, melancholics: what determines the preference is the direction the malady takes; if it bears upon the body, epilepsy, if upon the intelligence, melancholy.”
Seizures in most people with epilepsy can be controlled by drugs and surgery. The fact remains, however, that epilepsy and mood disorders such as depression affect quality of life and increase disability and healthcare costs.
Depression raises the risk for suicidal thoughts and attempts. Further, previous studies have shown that people who have both epilepsy and mood disorders tend to have worse seizure outcomes than those without mood disorders.
In the United States, about 2.3 million adults and more than 450,000 children and adolescents have epilepsy—and anyone can develop the disorder. In 2015, an estimated 16.1 million adults at least 18 years old in the US had at least one major depressive episode in the past year, according to federal figures.
“A number of genes have been found for epilepsy and understanding if these genes also might be causing depression is important,” Heiman says. “In particular, more studies should be done to understand the relationship between focal epilepsy and mood disorders.”
Source: Rutgers University