Redefining Major Depressive Episodes and Treatment Guide

Completely resolving patients’ depressive symptoms is the best chance they have for reducing the risk for depression recurrence, according to a study published in the Journal of Clinical Psychiatry.

Researchers from the University of California, San Diego retroactively studied 322 participants with a major depressive episode in order to create an empirically based, clinical useful definition of the end of a major depressive episode. They also wanted to test out the predictive validity of two resolution levels included in the current consensus definition of a major depressive episode recovery. The patients entered the National Institute of Mental Health Collaborative Depression Study with a major depressive episode between 1978 and 1981 and were followed for up to 31 years.

The patients were divided into groups of those with 8 consecutive weeks of asymptomatic major depressive episode or residual symptom resolution of their episode. The two levels of recovery were outlined based on weekly symptom status reports on all conditions which were reported via interviews conducted every six months.

About two thirds of patients (61.2 percent) recovered asymptomatically from their diagnosed major depressive episode, the researchers learned. This group did not experience a depressive episode relapse or recurrence 4.2 times longer than those patients who still had residual symptoms — a median of 135 weeks versus 32 weeks – the study authors reported.

The continuance of residual symptoms was linked to nearly a three times higher risk of a subsequent major depressive episode within a year (74 percent vs. 26 percent). Additionally, the patients with residual symptoms had a greater depressive illness burden for the following one or two decades as well as more long term difficulty with work, household functioning, and personal relationships.

First study author Lewis L. Judd, MD, explained in a press release that however long a patient experiences depressive symptoms is how long they should be treated. “If you treat a major depressive episode until there are no remaining symptoms, the individual is likely to enter a stable state of wellness and be free of depression for months or even years. As long as they have any residual symptoms, they are still ill and at high risk for relapse.”

There was a discrepancy between the length of time that groups stayed well, but it was not due to the patients’ levels of antidepressant treatment received, the authors said. The symptom resolution appeared more predictive than any other factor in regards to the length of time that the patients stayed free of a depressive episode.

The authors believe that four weeks of completely without any depressive symptoms should be the new standard for a major depressive episode and the goal for treatment.