Childhood maltreatment and non-suicidal self-injury: a systematic review and meta-analysis

Background Non-suicidal self-injury is being increasingly recognised as a prominent public health concern. Identification of early and modifiable risk factors is necessary to advance the screening and intervention efforts, particularly early detection of at-risk individuals. We aimed to examine childhood maltreatment, including its specific subtypes, in relation to non-suicidal self-injury. Methods We did a comprehensive meta-analysis of childhood maltreatment (overall, sexual abuse, physical abuse and neglect, and emotional abuse and neglect) in association with non-suicidal self-injury. We also provided a qualitative review of mediators and moderators of this association. We identified relevant articles published from inception to Sept 25, 2017, through a systematic search of Embase, MEDLINE, and PsycINFO. We extracted continuous and categorical data and assessed for potential moderators using ten study characteristics. We generated random-effects models for analysis and evaluated for publication bias. Findings We identified 71 publications that met eligibility criteria. Overall childhood maltreatment was associated with non-suicidal self-injury (odds ratio 3.42, 95% CI 2.74-4.26), and effect sizes for maltreatment subtypes ranged from 1.84 (1.45-2.34) for childhood emotional neglect to 3.03 (2.56-3.54) for childhood emotional abuse. Publication bias was not evident, except in the case of childhood emotional neglect. Across multiple maltreatment subtypes, we found stronger associations with non-suicidal self-injury in non-clinical samples. Interpretation With the exception of childhood emotional neglect, childhood maltreatment and its subtypes are associated with non-suicidal self-injury. Screening of childhood maltreatment history in non-suicidal self-injury risk assessments might hold particular value in community settings, and increased attention to childhood emotional abuse is warranted.