Short-Term Prognosis in Adolescents and Adults with Major Depressive Disorder and Associated Psychosocial Factors: A Prospective Study.

This prospective study examined whether short-term treatment outcomes differ between adolescents and adults with major depressive disorder (MDD) and evaluated the contribution of psychosocial factors to these differences. Adolescents and adults receiving treatment in the Department of Psychiatry were consecutively recruited between June 2023 and December 2024, including 115 adolescents (64.61%) and 63 adults (35.39%) in the final week-8 analysis set. Depressive symptom severity was assessed using the 24-item Hamilton Depression Rating Scale (HAMD-24). Anhedonia, sleep quality, interpersonal functioning, and social support were evaluated using the Snaith-Hamilton Pleasure Scale (SHAPS), the Pittsburgh Sleep Quality Index (PSQI), the Interpersonal Relationship Scale (IRS), and the Social Support Rating Scale (SSRS), respectively. Assessments were completed at baseline and at 2, 4, and 8 weeks after treatment initiation. At baseline, the two groups differed in educational attainment and illness duration (P < 0.05), whereas HAMD-24 scores were comparable. Sleep-related measures showed limited between-group differences, but adolescents reported more severe anhedonia, poorer interpersonal functioning, and lower social support than adults (P < 0.05). After 8 weeks of treatment, HAMD-24 scores decreased significantly in both groups, but adults achieved higher remission and overall effectiveness rates than adolescents (P < 0.001). In both age groups, poorer interpersonal functioning and lower social support were associated with less favorable prognosis, with stronger associations observed in adolescents. These findings suggest that psychosocial disadvantage may weigh more heavily on short-term treatment outcomes in adolescent MDD. Interventions that strengthen interpersonal functioning and social support may therefore be particularly relevant for improving prognosis in this population.