Dimension-Specific Childhood Maltreatment and Cross-Sectional Markers of Illness Burden in Treatment-Resistant Depression: A Retrospective Single-Center Study

Background/Objectives: We examined global and dimension-specific childhood maltreatment in relation to cross-sectional illness burden in treatment-resistant depression (TRD). Methods: This retrospective, single-center, case-only study included 104 records from November 2025 to June 2026. The Childhood Trauma Questionnaire–Short Form (CTQ-SF) was completed during TRD assessment. Primary outcomes were elapsed ongoing major depressive episode (MDE) duration and retrospectively reconstructed lifetime failed antidepressant-trial count; illness duration and previous MDEs were secondary. Models adjusted for age, sex, and extraction block; false discovery rate (FDR) correction covered 28 tests. Results: CTQ total and trauma load showed no significant linear associations. Per 5 points, physical abuse was associated with longer elapsed MDE duration (+50.3%; 95% CI, 24.0–82.2%; p < 0.001; q < 0.001) and more failed trials (IRR = 1.20; 95% CI, 1.10–1.30; p < 0.001; q < 0.001). Sexual abuse was associated with longer elapsed duration (+59.8%; 95% CI, 26.5–101.9%; p < 0.001; q = 0.001). Physical-abuse associations did not survive FDR correction in mutually adjusted subscale models; the failed-trial association also weakened after episode-duration adjustment. Emotional-neglect associations were inverse and require caution. Conclusions: These cross-sectional findings are hypothesis-generating and require prospective replication with standardized treatment histories and remission outcomes.