Jeanette M Johnstone, Janet D Carter, Suzanne E Luty, Roger T Mulder, Christopher M Frampton, Peter R Joyce

Adverse childhood experiences are well-recognized risk factors for a variety of mental health issues, including depression, suicide attempts and non-suicidal self-injury. However, less is known about whether childhood adversity, in the form of low parental care, overprotection and abuse, is associated with suicide attempt and non-suicidal self-injury within a sample of depressed adults. The sample of outpatients (n = 372) was drawn from two randomized depression trials. Childhood adversity variables, depression severity, age of first depressive episode (major depression episode onset), lifetime suicide attempt and non-suicidal self-injury were recorded at baseline. The association between variables and outcome measures was examined using partial correlations, univariate and multivariate logistic regressions. Low maternal care was significantly associated with suicide attempt; low paternal care was associated with non-suicidal self-injury; overprotection was not associated with either outcome. Other risk factors for suicide attempt were major depression episode onset and baseline depression severity. Major depression episode onset was also a risk factor for non-suicidal self-injury. Abuse, regardless of how it was measured, was not significantly associated with either behaviour after adjusting for its correlations with low maternal or paternal care. In this sample of depressed adults, the quality of ongoing, intra-familial relationships, as measured by levels of parental care, had a greater impact on suicide attempt and non-suicidal self-injury than abuse. As the findings were not a priori hypotheses, they require replication. Although the cross-sectional study design limits causal determination, the findings suggest different childhood risk factors for suicide attempt and non-suicidal self-injury and underscore the impact of low parental care on these two behaviours. These findings signal to clinicians the importance of asking specifically about suicide attempts, and non-suicidal self-injury, as well as levels of parental care in childhood. When endorsed, low parental care may be considered an important factor in contextualizing a patient's depression and potential risk for suicide and non-suicidal self-injury.