Overall and Gender-specific Associations between Dimensions of Adverse Childhood Experiences and Mental Health Outcomes among Homeless Adults: Associations Générales et Sexospécifiques Entre les Dimensions des Expériences Défavorables de L'enfance et les Résultats de Santé Mentale Chez les Adultes Sans Abri.

Objective The associations between adverse childhood experiences (ACEs) and psychopathology have been well-established in the general population. Research on ACEs in the homeless population has been limited. This study examined whether ACE exposure is associated with specific mental health outcomes among a national sample of homeless adults with mental illness and whether this association varies according to ACE dimension and gender. Methods This cross-sectional study utilized data from a national sample of 2,235 homeless adults with mental illness in Canada to evaluate their sociodemographic characteristics, exposure to ACEs, and mental health outcomes. Exploratory and confirmatory factor analyses were conducted to identify and confirm ACE dimensions (maltreatment, sexual abuse, neglect, divorce, and household dysfunction) from individual ACE items. Multivariable logistic regression was used to examine the associations between total ACE score and ACE dimensions with mental illness diagnoses and psychopathology severity. Results The mean total ACE score among all study participants was 4.44 (standard deviation [SD]: 2.99). Total ACE score was positively associated with several mental illness diagnoses and psychopathology severity. Unique associations were found between specific ACE dimensions and poor mental health outcomes. The prevalence of almost all ACEs was significantly higher among women. Yet, associations between several ACE dimensions and poor mental health outcomes existed uniquely among men. Conclusions There are unique and gender-specific associations between specific ACE dimensions and mental health outcomes among homeless adults. Better understanding of the mechanisms underlying these associations is needed to inform screening, prevention, and treatment efforts, particularly given the very high prevalence of ACEs among this vulnerable and marginalized population.