Serum inflammatory factors in adolescents with major depressive disorder at various ages of first onset

To characterize the association between serum inflammatory factors and clinical features in adolescents with major depressive disorder (MDD) at various ages of first onset. Adolescent patients (13–18 years) with MDD who were hospitalized in the Fourth People’s Hospital of Hefei City between January 2023 and June 2024 were classified as childhood-onset MDD (< 13 years; n = 48) or adolescence-onset MDD (≥ 13 years; n = 126). Healthy volunteers were recruited as controls. General demographic and clinical data were collected, serum IL-1β and IL-18 levels were measured using enzyme-linked immunosorbent assay, and severity of depressive symptoms and history of child abuse and neglect before 16 years of age were assessed with the Hamilton Depression Scale (HAMD-17) and Childhood Trauma Questionnaire (CTQ), respectively. Age and course of disease were significantly lower and CTQ total and physical abuse scores were significantly higher in patients with childhood-onset MDD vs. patients with adolescent-onset MDD. There was no significant difference in HAMD-17 score. After controlling for age, serum IL-1β levels were significantly higher and serum IL-18 levels were significantly lower in patients with childhood-onset MDD vs. adolescent-onset MDD. Logistic regression analysis indicated that age (OR = 0.231), IL-1β (OR = 2.293), and CTQ score (OR = 1.070) were associated with childhood-onset MDD. This study found differences in serum IL-1β levels and CTQ scores among patients with adolescent-onset MDD and childhood-onset MDD.