Identifying a physical indicator of suicide risk: Non-suicidal self-injury scars predict suicidal ideation and suicide attempts.

BACKGROUND: Suicide risk is challenging to quantify due to reliance on self-report, which is limited by individuals' lack of insight and the desire to conceal such intentions. Non-suicidal self-injury (NSSI) is one of the most robust predictors of suicidal ideation (SI) and suicide attempts (SA). Although NSSI often leads to permanent scarring, which can be assessed by objective physical examination, no research has examined whether scarring denotes tangible risk for SI and SA. The present study examined whether NSSI scar presence and number predict current SI and SA history. Further, we examined whether brooding would exacerbate the effects of NSSI scarring on SI or SA.
METHODS: Young adults (N=231; M=21.24 years; 78% female) completed self-report questionnaires assessing SA history, frequency of NSSI, presence/number of NSSI scars, brooding, current depressive symptoms, and SI.
RESULTS: NSSI scar presence and number predicted current SI and SA history after controlling for current depressive symptoms. Moreover, scar presence and number predicted current SI over and above the effects of SA history and NSSI frequency, method, and medical severity. Further, NSSI scar presence and number predicted SI more strongly among individuals with greater levels of brooding than among individuals with lower levels of brooding.
CONCLUSIONS: The presence and number of NSSI scars are objective physical indicators of risk for SI and SAs. Brooding may further heighten the risk of SI for individuals bearing NSSI scars.