antidepressants

Genes Contribute to Population-Based Differences in Antidepressant Response

5 Questions with Dr. Francis McMahon

doctor examining African American patient

Depression is one of the most common mental health conditions in the U.S., affecting nearly seven percent of American adults each year. With the increasing social and economic pressures of the modern world likely contributing to depressive symptoms, it is more important now than ever to study depression and the factors that contribute to recovery.

A number of variables contribute to an individual’s overall mental health and response to treatment, including elements of nature and nurture that have long been studied at the NIH. In a 2013 study, researchers led by IRP senior investigator Francis McMahon, M.D., set out to understand the complex genetic factors that he believed might help explain why antidepressants are less effective for African Americans with depression than for other populations. His research revealed that differences in socioeconomics and health explained most of those differences in antidepressant response, and the remaining differences were explained by differences in genetic ancestry, rather than self-reported race. The discovery that genetics play a role in this health disparity could help close the gap and improve depression treatment for African Americans.

Shedding Light on the Deep Darkness of Depression

Dr. Carlos Zarate with a participant in a neuroimaging study

In 2016, more than one in twenty American adults and one in ten adolescents experienced at least one major depressive episode. For nearly 45,000 of these individuals, their condition was severe enough that it led them to take their own lives. Unfortunately, the medications currently available to treat depression are not always effective and can take up to six weeks to substantially reduce symptoms.

To improve treatment and accelerate symptom relief, IRP senior investigator Carlos Zarate Jr., M.D., is working towards the development of new medications for depression, along with the identification of new drug targets and objective measures called biomarkers that yield information about how a patient is responding to treatment. In recent years, his lab has extensively investigated and assessed the effects of the anesthetic drug ketamine on depression and suicidal thoughts. Many of the patients in his trials have had marked and rapid responses to ketamine, sometimes within a single day or just a couple of hours. 

On Tuesday, November 13, Dr. Zarate participated in a Reddit “Ask Me Anything” (AMA) to answer questions from the public about the way depression is currently treated and the latest efforts to develop cutting-edge therapies for the condition. Read on for some of the most interesting exchanges that took place or check out the full AMA on Reddit.