Non-suicidal self-injury differentiates suicide ideators and attempters and predicts future suicide attempts in patients with eating disorders

Objective
We aimed first to identificate psychopathological variables differentiating between suicide ideators, suicide attempters and patients without suicide ideation or attempts, and second to identificate better predictors of suicide attempts longitudinally.
Method
We compared suicide ideation, hopelessness, borderline symptoms, frequency, types, number of different non‐suicidal self‐injury (NSSI) methods, intrapersonal and interpersonal functionality of NSSI in a sample of 238 patients with Eating Disorders (1) with no history of suicide ideation or suicide attempts (n = 150); (2) with recent suicide ideation (n = 65); and (3) with suicide attempts in the previous year (n = 23). In addition, we analyzed the predictive power of the mentioned variables over the number of suicide attempts 7 months after the first assessment.
Results
The group of suicide attempters showed a major number of different methods of NSSI, higher frequency of NSSI, cutting, and more NSSI intra and interpersonal functions than the group of ideators. Unlike in previous studies, hopelessness did not differentiate between patients with ideation and suicide attempts. In addition, the best predictor of suicide attempts 7 months later was frequency of NSSI at T1 (N = 123).
Conclusions
Cutting, frequency and different methods of NSSI, intra and interpersonal functions were risk factors that differentiated ideators from attempters, being frequency of NSSI the best predictor of suicide attempts longitudinally. Thus, patients with ED with NSSI should be the focus of preventive interventions for suicidal behavior.