An epigenetic candidate-gene association study of parental styles in suicide attempters with substance use disorders.

Suicide attempts (SA) are prevalent in substance use disorders (SUD). Epigenetic mechanisms may play a pivotal role in the molecular mechanisms of environmental effects eliciting suicidal behaviour in this population. Hypothalamic-pituitary-adrenal axis (HPA), oxytocin and neurotrophin pathways have been consistently involved in SA, yet , their interplay with childhood adversity remains unclear, particularly in SUD. In 24 outpatients with SUDs, we examined the relation between three parental dysfunctional styles and history of SA with methylation of 32 genes from these pathways, eventually analysing 823 methylation sites. Extensive phenotypic characterization was obtained using a semi-structured interview. Parental style was patient-reported using the Measure of Parental Style (MOPS) questionnaire, analysed with and without imputation of missing items. Linear regressions were performed to adjust for possible confounders, followed by multiple testing correction. We describe both differentially methylated probes (DMPs) and regions (DMRs) for each set of analyses (with and without imputation of MOPS items). Without imputation, five DMRs in OXTR, CRH and NTF3 significantly interacted with MOPS father abuse to increase the risk for lifetime SA, thus covering the three pathways. After imputation of missing MOPS items, two other DMPs from FKBP5 and SOCS3 significantly interacted with each of the three father styles to increase the risk for SA. Although our findings must be interpreted with caution due to small sample size, they suggest implications of stress reactivity genes in the suicidal risk of SUD patients and highlight the significance of father dysfunction as a potential marker of childhood adversity in SUD patients.

Childhood trauma and the severity of past suicide attempts in outpatients with cocaine use disorders.

Introduction: Suicide attempts have been associated with both cocaine use disorder (CocUD) and childhood trauma. We investigated how childhood trauma is an independent risk factor for serious and recurrent suicide attempts in CocUD. Method: 298 outpatients (23% women) with CocUD underwent standardized assessments of substance dependence (Diagnostic and Statistical Manual-mental disorders, fourth edition, text revised), impulsiveness, resilience, and childhood trauma, using validated tools. Suicide attempts history was categorized as single vs. recurrent or non-serious vs. serious depending on the lifetime number of suicide attempts and the potential or actual lethality of the worst attempt reported, respectively. Bivariate and multinomial regression analyses were used to characterize which childhood trauma patterns were associated with the suicide attempts groups. Results: 58% of CocUD patients reported childhood trauma. Recurrent and serious suicide attempts clustered together and were thus combined into "severe SA." Severe suicide attempt risk increased proportionally to the number of childhood traumas (test for trend, p = 9 × 10-7). Non-severe suicide attempt risk increased with impulsiveness and decreased with resilience. In multinomial regression models, a higher number of traumas and emotional abuse were independently and only associated with severe vs. non-severe suicide attempts (effect size = 0.82, AUC = 0.7). The study was limited by its cross-sectional design. Conclusion: These preferential associations between childhood trauma and severe suicide attempts warrant specific monitoring of suicide attempts risk in CocUD, regardless of the severity of addiction profiles.