Association of depression symptom severity with short-term risk of an initial hospital encounter in adults with major depressive disorder

Abstract

BackgroundDespite the availability of pharmacologic and nonpharmacologic treatment options, depression continues to be one of the leading causes of disability worldwide. The impact of depression symptom severity on short-term risk of hospitalization is not well established in the literature. This study evaluates the degree to which depression symptom severity in patients diagnosed with MDD is associated with risk of an initial hospital encounter (ER visit or hospitalization) in the short-term following an outpatient PHQ-9 assessment. MethodsAdult patients (≥18 years of age) with ≥1 PHQ-9 assessment in an outpatient setting (index date) and ≥1 MDD diagnosis within 6 months prior were included from the de-identified Optum Electronic Health Record database (April 2016-June 2019). Patients were categorized based on PHQ-9 scores obtained by natural language processing. Crude rates and adjusted absolute risks of all-cause, MDD-related, and suicidal ideation (SI)/suicide attempt (SA)-related hospital encounters within 30 days of patients’ PHQ-9 assessments were evaluated.ResultsThe study population consisted of 280 145 patients with MDD and ≥1 PHQ-9 assessment in an outpatient setting. Based on PHQ-9 scores, 26.9% of patients were categorized as having none/minimal depression symptom severity, 16.4% as mild, 24.7% as moderate, 19.6% as moderately severe, and 12.5% as severe. Among patients with none/minimal, mild, moderate, moderately severe, and severe depression, the adjusted absolute short-term risks of an initial all-cause hospital encounter were 3.9%, 4.3%, 4.9%, 5.7%, and 6.7%, respectively; of a MDD-related hospital encounter they were 0.8%, 1.0%, 1.3%, 1.6%, and 2.2%, respectively; of a SI/SA-related hospital encounter they were 0.1%, 0.1%, 0.1%, 0.3%, and 0.8%, respectively ConclusionsThese study findings indicate that depression symptom severity is a key driver of short-term risk of hospital encounters, emphasizing the need of timely interventions that can ameliorate depression symptom severity.