Co-Administration Treatment in Drug-Naïve Major Depression: Exploratory Real-World Patterns and Predictors in China.

Objective: Co-administration of psychotropic medications is common in major depressive disorder (MDD), yet its patterns and predictors remain underexplored in drug-naïve patients. This study aimed to characterize the prevalence and correlates of co-administration strategies at treatment initiation in China. Methods: In this multicenter, real-world study, we enrolled 1330 drug-naïve adults experiencing a depressive episode. Sociodemographic, clinical, and treatment data were collected at baseline. Univariate and multivariable logistic regression analyses identified factors associated with co-administration. Results: Co-administration was utilized in 27.14% of patients. Antipsychotic augmentation was the most common strategy (18.87%), surpassing the use of multiple antidepressants (7.89%), while mood stabilizers (lithium 3.76%; valproate 2.78%) were less frequent. Patients receiving co-administration were typically male, older, had lower education/income, and more severe depressive symptoms. The most prescribed adjunctive antidepressants were SNRIs, NaSSAs, bupropion, and trazodone; the most common antipsychotics were quetiapine, olanzapine, aripiprazole, and risperidone. Multivariable analyses identified sympathetic arousal (OR=1.64) and leaden paralysis (OR=1.30) as key independent predictors. Conclusion: Co-administration, particularly with antipsychotics, is frequently employed at the first treatment encounter for MDD in China. This practice appears to be a symptom-driven approach, targeting specific features like sympathetic arousal and leaden paralysis, which may reflect a pragmatic adaptation to local clinical realities beyond standard guidelines. Due to exploratory nature of the study, these findings are just hypothesis-generating, warranting further validation through more robust, longitudinal studies.