Characteristics and predictive factors of non-suicidal self-injury in patients with schizophrenia spectrum disorders

Abstract

Objective: We aimed to evaluate the characteristics and functions of non-suicidal self-injury (NSSI) in patients with schizophrenia spectrum disorders (SSD) and investigate predictive factors of NSSI. Methods: One hundred and two patients, aged between 18-65 with a diagnosis of SSD according to DSM-5 criteria, who were in remission were consecutively recruited to the study. Lifetime NSSI was assessed using the Inventory of Statements About Self-injury (ISAS). Positive and Negative Syndrome Scale (PANSS), Calgary Depression Scale (CDS), Suicide Probability Scale (SPS), Dissociation Scale (DIS-Q), Schedule for Assessing the Three Components of Insight (SAI), and Barratt Impulsivity Scale-11 (BIS-11) were administered to all patients who participated in the study. Logistic regression analysis was conducted to predict NSSI. Results: The prevalence of NSSI was 31.4% in our sample. ‘Self-cutting’ was the most common type (26.1%), and ‘affect regulation’ was the most common function of NSSI. 65.6% of the NSSI (+) group preferred to be alone while self-injurious behavior occurred. The time between the onset of feelings of an urge to injure self and the onset of NSSI was mostly less than three hours (46.9%). The significant predictors of NSSI were the previous history of suicide attempts (OR=2.693, p=0.040, 95% CI: 1.048-6.921) and greater severity of depressive symptoms (OR=1.216, p=0.001, 95% CI: 1.081-1.367). The previous history of suicide attempts was associated approximately threefold increase in the risk of NSSI. The probability of suicide was higher among patients with NSSI than patients without NSSI. Conclusion: Approximately 1/3 of the patients with SSD have NSSI. The results of our study indicate that patients with severe depressive symptoms and a history of previous suicide attempts are more at risk of injuring themselves and that the probability of suicide is higher in patients with NSSI than patients without NSSI. The reciprocal relationship of NSSI with suicide underlines the necessity of careful investigation for both clinical situations in this patient group. Assessment of NSSI should be a part of standard suicide risk assessment of SSD patients. Effective treatment of affective symptoms would help to reduce the risk of NSSI.