Biomedical subjects

Thomas G Schulze

Publications and source records attributed to Thomas G Schulze.

3 recordsLinked to original sources

PubMed2026

Persistent trauma three decades after the Halabja massacre: psychological symptom profiles and hair cortisol levels in gas attack survivors.

BACKGROUND: Survivors of the 1988 Halabja chemical attack have experienced severe, chronic trauma, yet limited research has examined the long-term psychological and biological consequences of chemical warfare exposure more than three decades later. AIMS: To examine long-term post-traumatic stress disorder (PTSD) symptoms, depression/anxiety symptoms, somatic symptoms and perceived stress among survivors of the Halabja chemical attack, and to investigate the associations of trauma exposure, sociodemographic factors and hair cortisol concentrations (HCCs) with psychological symptom severity and symptom profiles. METHOD: A total of 209 survivors of the Halabja chemical attack participated in structured interviews using culturally adapted and field-tested instruments, including the Post-Traumatic Stress Disorder Checklist for DSM-5, Hopkins Symptom Checklist-25, the Patient Health Questionnaire-13, the Perceived Stress Scale-14 and an adapted War and Adversity Exposure Checklist-26. Hair cortisol and cortisone concentrations were assessed as biomarkers of chronic stress. Data were analysed using correlations, independent-samples t-tests, multiple linear regression analyses, multinomial logistic regression and latent profile analysis (LPA). RESULTS: Survivors demonstrated a substantial long-term psychological symptom burden. Overall, 87.6% of participants exceeded the cut-off for probable PTSD symptoms, and 75.1% exceeded the cut-off for elevated depression/anxiety symptoms. Most participants (81.8%) reported exposure to 11 or more lifetime traumatic events. Men reported significantly greater cumulative trauma exposure, whereas women reported significantly greater somatic symptom severity. Higher educational attainment and employment were consistently associated with lower psychological symptom severity across multiple outcomes. HCCs were not significantly associated with PTSD symptoms or latent symptom-profile membership after adjustment for trauma exposure and psychosocial variables. The LPA identified four symptom-severity classes characterised by differing levels of PTSD and depression/anxiety symptoms. Greater cumulative trauma exposure and lower social support were associated with membership in more severe symptom classes. CONCLUSIONS: Survivors of the Halabja chemical attack continue to experience substantial psychological distress more than three decades after exposure. Long-term symptom severity appears to be more strongly associated with cumulative trauma exposure and psychosocial adversity than with HCCs. The findings highlight substantial heterogeneity in symptom presentation and support the need for long-term, culturally sensitive and trauma-informed mental health interventions for survivors of chemical warfare and mass violence.

Halabja chemical attack↗

PubMed2026

Effects of quetiapine on cognitive functioning in schizophrenia: evidence for the remyelination hypothesis?

Postmortem findings, neuroimaging data, and in-vitro models suggest a decrease in number and density of oligodendrocytes is driving cognitive deficits in schizophrenia (SCZ). Second-generation antipsychotics are discussed to improve oligodendrocyte dysfunction with most conclusive evidence available for quetiapine (QET). We postulate that sustained QET treatment leads to cognitive improvement in SCZ, particularly, in tests with high demands for working memory function. We further hypothesize that these effects are moderated by polygenic factors associated with hippocampus-related brain volumes, general white matter integrity, and/or oligodendroglia-related SCZ risk. Using data of the prospective PsyCourse study, we identified 166 patients with SCZ spectrum disorder receiving QET at one or two consecutive visits plus 166 matched patients without QET. Polygenic scores were calculated for subcortical brain volumes, measures of white matter integrity, and for cell type-specific genetic SCZ risks. QET treatment was consistently associated with improved cognitive function independent of time, specifically, in tests with high, but not with low to medium working memory load. Polygenic analyses did not reveal significant moderation effects. In contrary, low genetic SCZ risk specific for genes related to human oligodendrocyte function was associated with higher cognitive performance independent from QET. While we observed improved cognitive performance under QET in high working memory tests, we did not find evidence that polygenic factors associated with hippocampus-related brain volumes, white matter integrity, or oligodendroglia-related SCZ risk moderate this association. Thus, our tentative findings do not provide evidence for the hypothesis that polygenic estimates of hippocampal remyelination capacities influence the association between QET and cognitive performance in SCZ.

Humans↗

PubMed2025

Polygenic Contributions to Lithium Augmentation Outcomes in Unipolar Depression.

IMPORTANCE: Lithium augmentation is an effective treatment for patients with major depression after inadequate antidepressant response, but therapeutic outcomes vary considerably between individuals. Molecular studies may provide novel insights into treatment prediction and guide personalized therapy. OBJECTIVE: To investigate the association of polygenic risk scores (PRS) for schizophrenia (SCZ), major depressive disorder (MDD), and bipolar disorder (BIP) with clinical outcomes after lithium augmentation. DESIGN, SETTING, AND PARTICIPANTS: This cohort study analyzed prospectively assessed treatment outcomes in patients who underwent lithium augmentation. Disorder-specific PRS were calculated using well-powered genome-wide association study summary statistics. Participants were recruited from 13 psychiatric hospitals, primarily in the greater Berlin area, between 2008 and 2020. They were patients with MDD who showed inadequate response to at least 1 antidepressant, a baseline score of 12 or more on the 17-item Hamilton Depression Rating Scale (HAMD-17), adequate treatment duration (≥4 weeks), and no diagnostic or co-medication changes. Data analysis was conducted between June 2022 and November 2023. EXPOSURE: Polygenic risk scores for MDD, SCZ, or BIP. MAIN OUTCOMES AND MEASURES: Response was defined as a 50% or greater reduction in HAMD-17 score, remission as a HAMD-17 score of 7 or less. Cox proportional hazards models, adjusted for ancestry, demographic, and clinical covariates, were used to estimate hazard ratios (HRs) for favorable outcomes. RESULTS: Among 193 patients (mean [SD] age, 49.5 [13.4] years; 118 [61.1%] female and 75 [38.9%] male), higher BIP-PRS were associated with both response (HR, 1.29; 95% CI, 1.02-1.63; P = .03) and remission (HR, 1.52; 95% CI, 1.14-2.04; P = .004), explaining 2.51% and 4.53% of the variability in treatment outcomes, respectively. Individuals in the highest tertile of the BIP-PRS distribution had a 2.02-fold (95% CI, 1.15-3.53) higher likelihood of response and a 2.26-fold (95% CI, 1.17-4.36) higher chance of remission compared with those in the lowest tertile. Additionally, lower MDD-PRS was associated with better response to lithium augmentation (HR, 0.81; 95% CI, 0.66-1.00; P = .048; Nagelkerke R2 = 1.99%). No significant associations were observed between SCZ-PRS and response (HR, 1.00; 95% CI, 0.80-1.24; P = .97) or remission (HR, 1.12; 95% CI, 0.85-1.48; P = .42). CONCLUSIONS AND RELEVANCE: Individuals carrying a higher polygenic burden for BIP and lower polygenic risk for MDD are more likely to benefit from lithium augmentation. Our findings suggest that disease-related PRS may aid in developing treatment prediction models for lithium augmentation response in depression, potentially informing clinical decision-making.

Humans↗