Defining Response, Remission, and Residual Symptoms in MDD

In "Defining Response, Remission, and Residual Symptoms in MDD," our experts turn to the gap between what a scale measures and what a patient feels.

Dr. Alva raises the problem of patients who hear the word response and conclude they are cured. He asks Dr. DeBattista how he explains partial response, remission, and relapse, and how he keeps residual insomnia and anhedonia from being mistaken for the finish line.

Dr. DeBattista says he does not use those terms with patients at all, because they belong to clinical research. In trials, 25% improvement marks a partial response and 50% marks a responder, but that framework does not help the person in front of him. He will instead ask, do you feel depressed, and are you able to function at the level you could before you were depressed? Asked how he operationalizes meaningful improvement, Dr. DeBattista concedes that what matters to a patient may never appear on a scale. He describes a tertiary care patient who has had the kitchen sink thrown at her, including ECT and an implanted device. Only esketamine has helped, and only with her suicidality, which insurers cannot see on a scale. If the answers are no and yes, he calls that good evidence of remission. He will not use the word remission for anything short of a full response. To that patient, he says, it is a partial response. He teaches patients that any lingering symptom means the illness is still present and can bubble back up. A single residual symptom raises the risk of relapse, the risk of suicide, and the risk of an incomplete return to functional baseline.

On timing, he teaches four to eight weeks for antidepressants for maximum response, but notes conditional probability data showing modest odds at week eight if there is no response by 2-4 weeks.

Our next episode, "Positioning Faster-Acting MDD Therapies and Their Monitoring Demands," turns to which patients deserve a faster-acting agent before anything has failed.