During last 10 years, the number of non-suicidal self-injury patients (NSSI patients) in Department of Adolescent Psychiatry of Medical University in Łódź has doubled (from 20 to over 40%). According to DSM-5 criteria, NSSI are deliberate and superficial skin injuries. Such behaviours should be distinguished from suicidal behaviour disorder (SBD). However, the two display the high rate of co-occurrence.

The study covered 1300 patients (12–19 years of age) hospitalized during last 6 years. The analysis included various variables, e.g. demographic, familial, problems related to school and to peer relations, and variables describing NSSI.

The analyzed group consisted of 60,4% girls and 39,6% boys. Out of 43% of patients who performed NSSIs, 45% also confirmed BDS. The patients with diagnosed mental retardation and with schizophrenic psychoses performed significantly fewer NSSIs. The instrumental motive was the most frequently declared reason of self-injury (76%). The reactive (65%), and the illness-related motives (only 15%) were less frequent. In comparison to patients without self-injuries, the NSSI patients significantly more frequently (P < 0.05) experienced physical violence, unreciprocated love, played truant and repeated grades. Conflicts, delinquency, divorce, and lack of a sense of support were significantly more frequent in the family systems of NSSI patients. They more often experienced loss of their parent before age 15 and had close relatives suffering from mental disorders.

NSSI is a multi-dimensional issue that requires further research. Indicating potential risk factors allows for implementing efficient prophylactic, diagnostic and therapeutic actions.

The authors have not supplied their declaration of competing interest.