Antidepressant and Psychotherapy Treatment among Patients With Major Depressive Disorder and an Elevated PHQ-9 Score

Background

The PHQ-9 measures depression symptom severity and is recommended for use in clinical practice among patients with major depressive disorder (MDD). Objective To describe treatment among MDD patients with an elevated PHQ-9 score.

Methods

Using integrated medical and pharmacy claims and E.H.R. data between 7/1/2014 and 12/31/2018, we identified eligible adults with MDD, no other serious mental illness, commercial or Medicaid insurance, and benefits eligibility for six months prior and 12 months following an elevated PHQ-9 score. Patients were characterized for antidepressant and psychotherapy use.

Results According to PHQ-9 scores, most (41.8%) of the 29,236 eligible patients had mild severity, followed by moderate (27.6%); moderately severe (18.8%); and severe (11.9%). In the preceding six months, 32.3% of patients had antidepressant medication therapy, while only 7.3% had psychotherapy. In the following 12 months, 42.7% had at least one antidepressant drug, and 14.7% had at least one psychotherapy visit. Among the 18,057 (61.8%) patients with no prior treatments, 20.6% and 10.7% started antidepressant therapy and psychotherapy in the 12-month follow up, respectively. The adoption of both treatment modalities increased steadily with depression severity: antidepressant therapy from 18.2% (mild) to 24.7% (severe) and psychotherapy from 7.7% (mild) to 17.9% (severe). However, at the most severe levels, 61% of cases received no treatment during the first year.

Conclusions

Though depression symptom severity is associated with increased use of antidepressants and psychotherapy, overall treatment rates remain low. Novel interventions may be needed to reduce symptom severity and increase use of treatments for MDD.