Exposure to childhood maltreatment (CM) is associated with increased risk for developing substance use disorders (SUDs). CM exerts negative effects on cognitive abilities including intellectual performance, memory, attention, and executive function. Parallel cognitive impairments have been observed in SUDs. Hence, limited studies have examined the mediating effect of cognitive impairments in the relationship between CM and SUDs. In addition, most studies used concurrent self-report assessments in adult populations. Longitudinal studies that investigated the long-term consequences of CM on psychopathology, including SUDs, throughout childhood, adolescence, and adulthood are rare. Thus, the underlying developmental pathways between CM and SUDs are not clearly understood. In this article, we review the evidence that cognitive impairments mediate, at least in part, the relationship between CM and development of SUDs and propose a model that explains how CM increases the risk for SUDs through the development of a cognitive framework of vulnerability.

Several school-based prevention programmes have been developed and used to prevent, delay, or reduce substance misuse, and related problems among community samples of adolescents. However, findings indicate that many of these interventions are associated with null, small, or mixed effects in reducing adolescent substance misuse, in particular for those mostly at risk of transitioning to substance use disorders. These findings highlight the need to shift the focus of substance use prevention efforts toward intervention strategies which directly target high-risk adolescents. The Preventure programme was designed to target four personality risk factors for substance misuse: hopelessness, anxiety sensitivity, impulsivity, and sensation seeking. This article reviews findings from the previous trials of personality-targeted interventions (i.e., Preventure programme) with adolescents and discuss the promises and benefits of these interventions for targeting community samples of high-risk adolescents at school level for reducing substance misuse and related mental health problems. Findings indicated that this programme has been successful in reducing the rates of alcohol and illicit drug use and substance-related harms by ~50% in high-risk adolescents with the effects last for up to 3 years. These interventions were also associated with a 25% reduction in likelihood of transitioning to mental health problems, such as anxiety, depression, suicidal ideation, and conduct problems. The programme is particularly beneficial for youth with more significant risk profiles, such as youth reporting clinically significant levels of externalizing problems, and victimized adolescents. A key strength of the Preventure programme is that it is embedded in the community and provides substance use intervention at school level to the general samples of high-risk adolescents who might not otherwise have access to those programmes.

Background Adverse childhood experiences (ACEs) are strong risk factors for homelessness and poor health and functioning. We aimed to evaluate the lifetime prevalence of ACEs and their associations with health-related and functioning-related outcomes among homeless adults.Methods In this systematic review and meta-analysis, we searched from database inception to Nov 11, 2020, for original and peer-reviewed studies in English that documented lifetime prevalence of ACEs or associations between ACEs and health-related or functioning-related outcomes. We selected studies if they included a definable group of homeless adults and measured at least four ACE categories. We calculated pooled estimates of lifetime prevalence of one or more ACEs and four or more ACEs with random-effects models. We used the leave-one-out method in sensitivity analyses and studied meta-regressions to explore potential moderators of ACE prevalence. We also did a narrative summary of associations between ACEs and health-related and functioning-related outcomes, as there were too few studies on each outcome for quantitative meta-analysis. This study is registered with PROSPERO, CRD42020218741.Findings We identified 2129 studies through systematic search, of which 29 studies (16 942 individuals) were included in the systematic review, 20 studies (10 034 individuals) were included in the meta-analysis for one or more ACEs, and 15 studies (5693 individuals) were included in the meta-analysis for four or more ACEs. Studies included samples of adults experiencing homelessness in the USA, Canada, and the UK; participants in the included studies were predominantly male (65•2%) and mean ages ranged between 18•3 and 58•1 years, but many studies did not report race, ethnicity, and sexual and gender minority data. Lifetime prevalence of one or more ACEs among homeless adults was 89•8% (95% CI 83•7-93•7) and the lifetime prevalence of four or more ACEs was 53•9% (45•9-61•7). Considerable heterogeneity was identified in both meta-analyses (I²>95%). Of the potential moderators analysed, the ACE measurement tool significantly moderated the estimated lifetime prevalence of one or more ACEs and four or more ACEs, and age also significantly moderated the estimated lifetime prevalence of four or more ACEs. In the narrative synthesis, ACEs were consistently positively associated with high suicidality (two studies), suicide attempt (three studies), major depressive disorder (two studies), substance misuse (two studies), and adult victimisation (two studies).Interpretation The lifetime prevalence of ACEs is substantially higher among homeless adults than among the general population, and ACE exposure might be associated with prevalence of mental illness, substance misuse, and victimisation. Policy efforts and evidence-based interventions are urgently needed to prevent ACEs and address associated poor outcomes among this population.Funding Rhodes Trust and Canadian Institutes of Health Research.

We examined the hypothesis that exposure to childhood maltreatment increases the vulnerability to Adult Victimization (AV) in a homeless population (N = 500). We also investigated the effects of specific types (emotional, physical, and sexual) and cumulative experience of childhood maltreatment on AV, and whether gender moderates these relationships. All three groups with AV experience (emotional, physical, and sexual) indicated higher exposure to childhood abuse and cumulative maltreatment, and those who were sexually victimized as an adult showed higher exposure to childhood neglect. In addition, exposure to childhood maltreatment had type-specific and cumulative effects on AV. Exposure to all types of childhood abuse maintained a strong direct association with AV, regardless of demographic characteristics, including age, ethnicity, marital status, education level, and housing situation. In addition, exposure to physical neglect showed a significant relationship with Adult Sexual Victimization. Cumulative experience of childhood maltreatment was consistently associated with cumulative risk of experiencing AV. Gender had no significant effect on these relationships. Findings suggest that intervention programs in homeless population should consider the history of childhood maltreatment and its characteristics to increase the effectiveness of intervention strategies for AV in this population.