Hospital-Presenting Intentional Self-Harm and Events of Undetermined Intent in Croatia from 2017 to 2023.

Self-harm is the most significant risk factor for death by suicide. The aim of this study is to present trends and characteristics of hospital-presenting intentional self-harm and events of undetermined intent in Croatia from 2017 to 2023, with a focus on sex and age differences, in order to identify the at-risk groups towards whom prevention activities should be directed. Data were collected from the National Public Health Information System, and hospitalization rates were analyzed by sex, age, and year of hospitalization. The average hospitalization rate for intentional self-harm was 27.46 per 100,000, while the overall rate (including events of undetermined intent) was 44.47 per 100,000. Trends over the years indicate a general increase in hospitalization rates from 2017 to 2023, with the exception of 2020, when a temporary (statistically non-significant) decline was recorded. The highest rate in the observed period was reached in 2022. Furthermore, significant sex differences were observed. The hospitalization rate for intentional self-harm was statistically significantly higher among females (24% lower in males). However, when events of undetermined intent were included, the hospitalization rate became statistically significantly higher among males (7% higher compared to females). The highest hospitalization rates were recorded among females aged 15-19 years, peaking in 2022 (195.76 per 100,000). It is necessary to strengthen the system of monitoring and diagnostics and to develop targeted, gender-sensitive preventive interventions in order to reduce the risk of self-harm and the associated risk of suicide mortality.