Prevalence of Residual Symptoms in Adults With Depression or Major Depressive Disorder on Antidepressant Monotherapy: A Retrospective, Longitudinal Analysis of US Health Insurance Claims and Electronic Health Record Data

Background: Residual symptoms are ongoing depressive symptoms occurring during antidepressant treatment (ADT). Patients with residual symptoms have increased risk of relapse and morbidity, leading to poor functioning. This retrospective, observational study assessed the prevalence of residual symptoms in adults with depression or major depressive disorder (MDD) receiving ADT.

Methods: De-identified health insurance claims and electronic health records between March 1, 2019, and April 30, 2024, from the HealthVerity database were analyzed. Study population included patients aged ≥18 years with ≥1 inpatient or outpatient diagnosis of depression or MDD, with continuous enrollment ≥12 months before and ≥12 months after the index diagnosis, and prescribed any ADT. Patients with psychosis or depression-related diagnoses during baseline were excluded. A primary outcome was the assessment of 3 representative categories of residual symptoms (sleep disturbances, cognitive impairment, sexual dysfunction) in the posttreatment index period. Results were summarized by descriptive statistics.

Results: 6,315,125 patients met inclusion criteria. 66% were female, and median age was 41.0 (IQR: 29.0–56.0) years. Overall, 2,822,874 (44.7%) had ≥1 ADT claim. Median length of ADT was 334.0 (IQR: 151.0–649.0) days. Among those receiving monotherapy, 445,399 (16.2%) reported ≥1 residual symptom posttreatment index, with an overall annualized number of residual symptoms of 3.9 per patient and a median of 1.7 (IQR: 0.8–3.7). Of those with residual symptoms, 82.0% reported sleep disturbances, 14.1% cognitive impairment, and 9.2% sexual dysfunction.

Conclusion: Real-world data underscore the burden of depression and limitations of ADT. Variations in residual effects by ADT class are under investigation.