More than 30 million people in the United States take antidepressants each year. For most of those cases, the drug selection and dose is an educated guess to get people what they need to get through the day. It can often mean several attempts of trial-and-error to get to the right balance for the patient.

But now an American team is starting to publish results of investigations since 2012 attempting to get diagnosis and treatment right on the first visit.

EEG brain tests of the electrical signals within the brain are one indicator showing whether the most common class of antirdepressant, known as selective serotonin reuptake inhibitor, or SSRIs, are viable in certain cases of depression, the study authors describe in the journal JAMA Psychiatry.

The imaging scans are the first of a part of an ongoing series of trials called EMBARC, short for “establishing moderators and biosignatures of antidepressant response in clinical care.”

The trials are aimed at nothing less than changing the status quo when it comes to treating depression through chemical means, said Madhukar Trivedi, director of the Center for Depression Research and Clinical Care at UT Southwestern Medical Center.

“I expect these studies will have a widespread effect on how we design and plan treatment approaches,” said Trivedi. “My goal is to establish blood tests and brain imaging as standard strategies in the treatment of depression.”

The randomized clinical trial assessed 296 patients with a major depressive disorder. The scientists focused on the rostral anterior cingulate cortex, a part of the brain deep in the front of the left hemisphere of the brain. Of particular interest were higher theta activity levels in that small segment of the brain.

The patients were assessed at baseline and one week after the trial began. Interventions during the eight weeks included either sertraline (the most common brand of which is Zoloft), or a placebo.

The increased theta activity was associated with significantly greater depressive symptom improvement, even when controlling for other variables, the researchers conclude.

“Increased pretreatment rACC theta activity represents a nonspecific prognostic marker of treatment outcome,” the paper states. “This is the first study to date to demonstrate that rACC theta activity has incremental predictive validity.”

When combined with blood tests, brain imaging and other biology-based tests, Trevedi said he and his team hope to have 80 percent accuracy predicting whether an antidepressent will work for a patient the first time. 

“The bottom line is to reduce the trial-and-error process that can be so devastating to patients,” said Trevedi.

Other teams have tried to look into the standardization of antidepressant selection and effectiveness. For instance, a Kings College London team published results about a blood test on a series of biomarkers two years ago, which they say was near 100 percent accurate.