1 Unit of Mental Health and Wellbeing, Warwick Medical School, The University of Warwick, Coventry, UK.
2 Birmingham and Solihull Mental Health NHS Foundation Trust, Birmingham, UK.
Int J Soc Psychiatry. 2019 Mar;65(2):114-122. doi: 10.1177/0020764019827986. Epub 2019 Feb 18.
Impulsivity may be an important risk factor in terms of future self-harm. However, the extent of this, whether it may relate to self-harm that is new in onset and/or repetition of self-harm, and the detail of any interaction with mood instability (MI) and childhood sexual abuse (CSA) requires detailed examination.
We used the 2000 Adult Psychiatry Morbidity Survey and an 18-month follow-up data to test hypotheses relating to the role of impulsivity, CSA and MI in the inception and persistence of self-harm.
We assessed associations of impulsivity with (1) suicidal self-harm (SSH) and (2) non-SSH (NSSH) at baseline and follow-up, controlling for confounders including MI. Finally, we tested whether impulsivity mediated the relationship between CSA and self-harm.
A total of 8,580 respondents were assessed at baseline and 2,406 at follow-up as planned. Impulsivity significantly predicted emergence of new NSSH at 18-month follow-up even after adjustment for MI and other confounders. Impulsivity did not significantly predict repetition of NSSH, or repetition or new inception of SSH, even before inclusion of MI in the model. However, the absolute numbers involved were small. Cross-sectionally, impulsivity was a stronger mediator of the link between CSA and SSH (13.1%) than that between CSA and NSSH (4.8%).
Impulsivity may increase the risk of future development of NSSH independently of MI, which is clinically important for risk assessment. The involvement of impulsivity in the repetition of self-harm generally appears less certain. However, impulsivity may have a role in SSH in the context of previous CSA.
冲动性可能是未来自我伤害的一个重要风险因素。然而，其程度、是否与新发病或重复发病的自我伤害有关，以及与情绪不稳定（MI）和儿童期性虐待（CSA）的任何相互作用的细节，都需要详细检查。
我们使用 2000 年成人精神病发病率调查和 18 个月的随访数据，测试与冲动性、CSA 和 MI 在自我伤害的发生和持续中的作用相关的假设。
我们评估了冲动性与（1）自杀性自我伤害（SSH）和（2）非自杀性自我伤害（NSSH）在基线和随访时的关联，控制了包括 MI 在内的混杂因素。最后，我们测试了冲动性是否在 CSA 和自我伤害之间的关系中起中介作用。
共有 8580 名受访者在基线时接受评估，2406 名受访者按计划在随访时接受评估。即使在调整了 MI 和其他混杂因素后，冲动性仍显著预测了 18 个月随访时新出现的 NSSH。冲动性并未显著预测 NSSH 的重复发生，或 SSH 的重复发生或新发病。然而，所涉及的绝对数字很小。在不包括 MI 的情况下，冲动性是 CSA 与 SSH 之间联系的更强中介（13.1%），而不是 CSA 与 NSSH 之间联系的更强中介（4.8%）。
冲动性可能会增加未来发生 NSSH 的风险，而与 MI 无关，这对风险评估具有重要的临床意义。冲动性在自我伤害的重复发生中的作用一般不太确定。然而，在先前 CSA 的背景下，冲动性可能在 SSH 中起作用。
