Many studies have highlighted the detrimental effect of childhood maltreatment (CM) on depression severity and the course of illness in major depressive disorder (MDD). Yet our understanding of how CM influences the dynamic symptom change throughout a patient’s trajectory remains limited. Hence, we investigated the impact of CM on depression severity in MDD with a focus on various treatment phases during inpatient treatment and after discharge (1 or 2 years later) and validated findings in a real-world setting.

We used longitudinal data from a cohort study sample (n = 567) and a clinical routine sample (n = 438). CM was measured with the Childhood Trauma Questionnaire (CTQ), and depression severity was assessed using Beck’s Depression Inventory (BDI). The long-term clinical trajectory was assessed using the Life Chart Interview.

Our analyses revealed that CM significantly increased depression severity before, during, and after inpatient therapy in both samples. Although CM was associated with higher depression severity at the beginning of inpatient treatment and lower remission rates upon discharge, no discernible impact of CM was evident on the relative change in symptoms over time during inpatient treatment. CM consistently predicted higher relapse rates and lower rates of full remission after discharge during long-term follow-up in both samples.

Our findings affirm the link between CM and the development of more severe and persistent clinical trajectories within real-world clinical settings. Furthermore, conventional psychiatric treatments may not lead to comparable outcomes for individuals with a history of CM, underscoring the necessity for tailored therapeutic interventions.

Individuals at risk for bipolar disorder (BD) have a wide range of genetic and non-genetic risk factors, like a positive family history of BD or (sub)threshold affective symptoms. Yet, it is unclear whether these individuals at risk and those diagnosed with BD share similar gray matter brain alterations.

In 410 male and female participants aged 17–35 years, we compared gray matter volume (3T MRI) between individuals at risk for BD (as assessed using the EPIbipolar scale; n = 208), patients with a DSM-IV-TR diagnosis of BD (n = 87), and healthy controls (n = 115) using voxel-based morphometry in SPM12/CAT12. We applied conjunction analyses to identify similarities in gray matter volume alterations in individuals at risk and BD patients, relative to healthy controls. We also performed exploratory whole-brain analyses to identify differences in gray matter volume among groups. ComBat was used to harmonize imaging data from seven sites.

Both individuals at risk and BD patients showed larger volumes in the right putamen than healthy controls. Furthermore, individuals at risk had smaller volumes in the right inferior occipital gyrus, and BD patients had larger volumes in the left precuneus, compared to healthy controls. These findings were independent of course of illness (number of lifetime manic and depressive episodes, number of hospitalizations), comorbid diagnoses (major depressive disorder, attention-deficit hyperactivity disorder, anxiety disorder, eating disorder), familial risk, current disease severity (global functioning, remission status), and current medication intake.

Our findings indicate that alterations in the right putamen might constitute a vulnerability marker for BD.