370. Antidepressant prescribing patterns at initial visits for patients with mild depression: a retrospective study

Abstract

Abstract Background The efficacy of antidepressants for mild depression remains debated. International guidelines generally recommend psychosocial interventions as first-line treatment for mild symptoms, yet antidepressants are frequently initiated at the first psychiatric visit in routine clinical settings. However, empirical data on the prevalence and symptom-level factors influencing prescribing decisions for mild depression remain limited. Aims & Objectives This study aimed to investigate antidepressant prescribing patterns at initial psychiatric consultations for mild depression and identify symptom-related factors associated with such prescribing decisions. Method A retrospective chart review was performed on 1,508 outpatients diagnosed with depression at Kyorin University Hospital between 2020 and 2024. Mild depression was defined as a Quick Inventory of Depressive Symptomatology Self Report (QIDS-SR) score of 6-10 at the initial visit, and 171 adult patients met eligibility criteria. Patients were classified into an antidepressant group and a non-antidepressant group based on whether any antidepressant was prescribed at the first visit. Demographic variables, baseline QIDS-SR total scores, and individual QIDS-SR item scores were compared using independent two-sample t-tests or chi-square tests. Logistic regression analysis was performed to examine associations between individual QIDS-SR item scores and antidepressant prescription. Among patients receiving antidepressant monotherapy, symptom-level differences across antidepressant categories were also examined using one-way analysis of variance. Results Of the 171 eligible patients, 76 (44.4%) initiated any pharmacotherapy at the first visit, and 48 (28.1%) were prescribed antidepressants. The antidepressant and non-antidepressant groups did not differ significantly in age, sex distribution, or baseline QIDS-SR total scores. At the symptom level, the QIDS-SR “increased weight” item score was significantly lower in the antidepressant group compared with the non-antidepressant group (0.1 ± 0.4 vs. 0.3 ± 0.7, p = 0.03). Logistic regression indicated a consistent but nonsignificant trend toward an inverse association between increased weight and antidepressant prescription (B = −0.63, p = 0.09). Among participants who were prescribed antidepressant monotherapy, 20 were treated with selective serotonin reuptake inhibitors, 7 with serotonin–norepinephrine reuptake inhibitors, 8 with mirtazapine, 5 with vortioxetine, and 5 with others. Comparisons of QIDS-SR items among these categories revealed no statistically significant differences. Discussion & Conclusions Antidepressants were initiated in approximately 30% of patients with mild depression at their initial consultation in a university hospital setting, highlighting a divide between guideline recommendations and clinical practice. Higher weight gain appeared to be associated with a lower likelihood of antidepressant prescription, potentially reflecting clinicians’ perceptions of lower illness severity. Concerns regarding weightrelated side effects of certain antidepressants may also have influenced prescribing decisions. Overall, prescribing decisions were not strongly linked to specific symptom profiles, implying that other clinical or contextual factors may play a more decisive role in real-world treatment selection. Further largescale, prospective studies are warranted to elucidate the determinants and outcomes of initiating pharmacotherapy for mild depression.