Depression has a high disability rate and is projected to become the leading cause of disability worldwide by 2030. Real-world evidence indicates that even after systematic treatment and clinical symptom remission, functional impairment often persists among depression patients. However, there is a lack of research on long-term functional outcomes and influencing factors in first-episode depression patients in China.

To investigate the overall functional outcome of patients with first-episode depressive disorder after 7 years and to analyse the influencing factors of adverse functional outcome.

A total of 346 patients were enrolled from outpatient and inpatient settings at the Hebei Mental Health Center between May 2013 and May 2016. Eligible participants met the following criteria: Hamilton Depression Scale-17 (HAMD-17) score≥18, aged 18-60 years, who met the diagnostic criteria for single episode of major depressive disorder in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-Ⅳ) were included. Through naturalistic observational follow-up, demographic characteristics, disease features, and treatment details were collected. At the 7-year follow-up, the Treatment Emergent Symptom Scale (TESS) was used to assess adverse drug reactions, the Medication Adherence Rating Scale (MARS) evaluated treatment adherence, and the Global Assessment of Functioning (GAF) measured overall functional level. Patients in remission at the 7-year follow-up were divided into two groups based on GAF scores: the good functional outcome group (GAF>70) and the poor functional outcome group (GAF≤70). Multivariate Logistic regression analysis was performed to identify factors associated with poor functional outcomes.

A total of 138 cases were completed 7-year follow-up, including 127 cases in remission stage. The good overall function group was 46 cases (36.2%). The poor overall function group was 81 cases (63.8%). At the initial onset, there were significant differences between the overall poor-function group and the good-function group in terms of occupation and educational level (P<0.05). The total number of episodes during the 7-year period in the group with overall poor function, the proportion of episodes with psychotic symptoms, and the TESS total score at follow-up after 7 years were higher than those in the group with good function (P<0.05). The multivariate Logistic regression analysis results showed that a higher total number of episodes over 7 years (OR=1.509, 95%CI=1.083-2.102) and a higher TESS total score at 7-year follow-up (OR=1.067, 95%CI=1.002-1.136) were risk factors for poor global functional outcomes in patients after 7 years, while a higher education level at first onset (OR=0.486, 95%CI=0.268-0.878) served as a protective factor (P<0.05).

Among patients with first-episode depressive disorder, 63.8% had poor global functioning after 7 years. A higher number of relapses and more severe medication side effects increased the risk of adverse outcomes, while patients with higher education levels had relatively better functional outcomes at the 7-year follow-up.