The association between child maltreatment and mental disorders in the Australian Child Maltreatment Study

ObjectivesTo examine the associations between experiences of child maltreatment and mental disorders in the Australian population. DesignPopulation-representative survey conducted by computer-assisted telephone interviewing. Setting, participantsAustralian residents aged 16 years and older. Main outcome measuresMental disorder diagnoses of lifetime major depressive disorder, current alcohol use disorder (mild, moderate and severe), current generalised anxiety disorder and current post-traumatic stress disorder. ResultsMore than one in three Australians (3606/8503 surveyed participants; 38.0%; 95% CI, 36.7-39.3%) met the diagnostic criteria for a mental disorder. The prevalence of mental disorders in non-maltreated participants was 21.6% (95% CI, 19.9-23.3%; n = 851). This increased to 36.2% (95% CI, 33.5-38.9%; n = 764) for those who experienced a single type of maltreatment and 54.8% (95% CI, 52.6-56.9%; n = 1991) for participants who experienced multi-type maltreatment. Compared with non-maltreated Australians, maltreated participants had about three times the odds of any mental disorder (odds ratio [OR], 2.82; 95% CI, 2.47-3.22), generalised anxiety disorder (OR, 3.14; 95% CI, 2.48-3.97), major depressive disorder (OR, 3.19; 95% CI, 2.68-3.80) and severe alcohol use disorder (OR, 2.62; 95% CI, 1.83-3.76), and almost five times the odds of post-traumatic stress disorder (OR, 4.60; 95% CI, 3.00-7.07). Associations between experiences of child maltreatment and mental disorders were strongest for sexual abuse, emotional abuse and multi-type maltreatment. The strength of the associations did not differ by gender. Adjustment for childhood and current financial hardship and for current socio-economic status did not significantly attenuate the associations. ConclusionsMental disorders are significantly more likely to occur in individuals who experience child maltreatment, particularly multi-type maltreatment. Prevention of child maltreatment provides an opportunity to substantially reduce the prevalence of mental illness and improve the health of the Australian population.