Tehran University of Medical Sciences Iranian Journal of Psychiatry 1735-4587 0 0 2026 09 06 1 11 Narzikulova Dilnoza Department of International Relations, Navoi State University, Navoiy, Uzbekistan. Qilichev Rajab Department of Social Sciences, Bukhara State Pedagogical Institute, Bukhara, Uzbekistan. Komilov Kamol Department of Research, University of Tashkent for Applied Sciences, Tashkent, 11211, Uzbekistan AND Department of Architecture and Civil Engineering, Tashkent University of Architecture and Civil Engineering, Tashkent, Uzbekistan AND Department of Civil Engineering, Karakalpak State University, Nukus, Uzbekistan. Shakhlo Mirzaeva Department of Social Sciences, Pedagogy and Psychology, Tashkent State Medical University, Tashkent, Uzbekistan. Ernazarova Rano Department of Psychology, Karshi State University, Karshi, Uzbekistan. Jonibek Khayitov Department of Technological Education, Shahrisabz State Pedagogical Institute, Shahrisabz, Uzbekistan. 2026 06 20 2026 08 05 Objective: Major depressive disorder (MDD) is highly heterogeneous, and adverse childhood experiences (ACEs) contribute significantly to its variability. While abuse-type ACEs are linked to worse outcomes, the specific mechanisms remain poorly understood. This study tests a novel model in which abuse-specific ACEs, compared to neglect or household dysfunction, exert a stronger influence on depression severity by increasing repetitive negative thinking (RNT), which in turn amplifies somatic symptom burden. Method: In a cross-sectional study, 435 adults with a confirmed DSM-5 diagnosis of MDD were recruited from psychiatric clinics. Participants completed the Childhood Trauma Questionnaire (CTQ), the RNT Questionnaire (RNTQ), the Patient Health Questionnaire-15 (PHQ-15) for somatic symptoms, and the Beck Depression Inventory-II (BDI-II). Using structural equation modeling (SEM), we tested a dual mediation model where abuse, neglect, and household dysfunction ACEs predicted BDI-II scores via direct and indirect pathways, with a focus on the sequential path through RNT and somatic symptoms. Results: The model demonstrated excellent fit (CFI = 0.96, RMSEA = 0.04) and accounted for 54% of the variance in depression severity (R² = 0.54). Abuse ACEs had a significantly stronger total effect on depression severity than other ACE types (β = 0.41 versus ≤ 0.18, P < 0.01) and also exerted a significant direct effect on depression severity (β = 0.22, P = 0.012). The specific indirect pathway from abuse ACEs to RNT to somatic symptoms to depression was also significant (β = 0.19, 95% CI [0.13, 0.26]), accounting for 46% of the total effect of abuse on depression (total effect β = 0.41, P < 0.001). This pathway was significantly stronger (P < 0.001) than analogous pathways from neglect or household dysfunction ACEs. Conclusion: The path from childhood abuse to severe depression is characterized by a cognitive-somatic cascade: abuse fuels persistent negative thinking, which exacerbates the perception and burden of physical symptoms, ultimately deepening depressive severity. This identifies a specific phenotypic profile (high RNT + high somatic burden) associated with abuse histories, highlighting essential targets for tailored intervention in trauma-informed depression care. https://ijps.tums.ac.ir/index.php/ijps/article/view/4676 https://ijps.tums.ac.ir/index.php/ijps/article/download/4676/1352