The Long- Term Course of Adolescent-Onset Major Depressive Disorder in Females: A 10-Year Cohort Study on Recurrence, Suicide Risk, and Service Use

BACKGROUND: Adolescent-onset major depressive disorder (MDD) is associated with high morbidity, recurrence, and suicide risk. However, few studies have prospectively examined its long-term course into emerging adulthood. METHODS: Ninety-four female adolescents (aged 15-17 years) diagnosed with MDD between January and August 2012 were enrolled. After 10 years, 54 participants were reassessed. Psychiatric diagnoses were established using the Kiddie Schedule for Affective Disorders and Schizophrenia (K-SADS) at baseline and the Structured Clinical Interview for DSM-5 Disorders (SCID-5) at follow-up. Global functioning was rated using the Global Assessment of Functioning (GAF). At both time points, participants completed the Beck Depression Inventory (BDI), Emotional Autonomy Scale (EAS), Parent Adolescent Relationship Questionnaire (PARQ), and Identity Development Assessment Tool (IDAT). RESULTS: Nearly all participants (94.4%) experienced recurrent depressive episodes, and 79.6% met criteria for at least one current psychiatric disorder at the follow-up assessment. The most common current diagnoses were MDD and ADHD (each 35.2%). The mean GAF score at follow-up was 64.2 ± 8.1, indicating moderate functional impairment. Lifetime suicide attempts were reported by 32 participants (59.3%). Runaway behaviour was a significant risk factor for suicidal behaviour (OR = 5.91, 95% CI [1.27-27.54], p = 0.024), while earlier psychiatric contact (OR = 0.40, 95% CI [0.18-0.88], p = 0.027) served as a protective factor. Despite the ongoing need, one fifth of individuals (n=11) was receiving psychiatric care in emerging adulthood. CONCLUSIONS: Adolescent-onset Major Depressive Disorder (MDD) is highly recurrent and carries a significant long-term risk for further psychiatric issues and suicide. However, the rigid transition from child to adult services at age 18 appears to disrupt care continuity. Runaway behaviour should be considered a marker of suicide risk, whereas earlier psychiatric contact may be protective. Youth psychiatry programs are needed to bridge the child-adult service gap for adolescents with depression.