Transcript: 

An estimated 21 million adults in the US, or 8.3% of the adult population, experienced an episode of major depressive disorder, or MDD, in 2021.

Many patients with MDD go untreated. In a 2018 study of more than 20,000 US adults with depression, 30% reported needing treatment but not receiving it.

Even among treated patients, only 30 to 50% respond to antidepressant medication in clinical trials, and response rates in clinical practice are even lower.

Available monoamine-based antidepressants take 4 to 8 weeks to reach their clinical effect.

With low initial response rates, periodic outcomes measurement is essential for making necessary treatment adjustments in a timely manner.

The first priority for a patient with an episode of MDD is to achieve symptom remission.

According to the APA, remission of MDD is defined as at least 3 weeks of the absence of both sad mood and reduced interest or pleasure and no more than 3 of the 9 core symptoms of a major depressive episode persisting.

Since the APA definition of MDD requires the presence of 5 symptoms, remission can be achieved with only a 40% reduction in the number of core MDD symptoms present.

Research suggests that even mild residual symptoms at the end of a depressive episode are associated with significant psychosocial disability and increased risk of relapse, compared with being asymptomatic.

According to the APA, the goal of acute treatment of MDD “is to achieve remission and a return to full functioning and quality of life.”

Thus, the goal of achieving remission does not encompass the entire clinical picture.

Remission of symptoms is a stop along the road, a critical threshold to be crossed, but the ultimate goal is to help patients reclaim a healthy lifestyle and sense of normalcy.

Patient-rated depression rating scales include the Inventory of Depressive Symptoms (also available in a clinician-rated version); the Beck Depression Inventory; the Quick Inventory of Depressive Symptoms; and the Patient Health Questionnaire-9 (PHQ-9).

Clinician-rated scales include the Montgomery-Asberg Depression Rating Scale, known as the MADRS [pronounced MAH-drahs]; the Clinician Global Impression scale, or CGI, which offers Severity and Improvement subscales; and the 17-item Hamilton Rating Scale of Depression (HAM-D).

The widely-used PHQ-9 and HAM-D will serve as examples here.The PHQ-9 asks patients to rate 9 items that correspond to the 9 core symptoms of the APA diagnostic criteria for MDD. Each item is scored on a 4-point scale, with a maximum possible total score of 27.

MDD is present if 5 or more of the 9 core depressive symptoms are present more than 7 days in the previous 2 weeks, and if 1 of those symptoms is depressed mood or anhedonia.

Depression severity ratings range from “Minimal”, a score of 0 to 4, to “Severe”, a score of 20 to 27.

Symptom control does not tell the whole story. A patient scoring 4 on the PHQ-9 – indicating minimal depression – may still experience up to 4 symptoms several days during each 2-week assessment period.

The HAM-D is a 17-item, clinician-rated scale wherein each item is ranked on 3- to 5-point Likert scales.

The HAM-D also captures the 9 core symptoms of MDD, but it provides a more granular view of symptoms such as insomnia, which it breaks down by time of occurrence within the sleep cycle.

The HAM-D also evaluates anxiety, somatic symptoms, and sexual dysfunction, any of which may greatly impact a patient’s quality of life and functional status.

Depression severity ratings range from “Normal”, a score of 0 to 7, to “Very Severe Depression”, a score of 23 to 50.