LAUSR

Self-harm including self-poisonings is a major health problem among young girls, and there is a concern that the mobility restrictions and social distancing associated with the Covid-19 pandemic may have further reinforced this. Studies examining trends of self-harm report mixed results, while a handful studies find an increase in selfpoisoning in the first pandemic year. Whether this development continues beyond 2020 is unknown. In this study, we analyse trends in admissions for self-poisoning in specialist health care (SHC) and in contact with the Norwegian Poisons Information Centre (NPIC) prior to and during the pandemic among Norwegian girls aged 10–19 years. We also report the most prevalent poisoning agents. We obtained data from the Norwegian Patient Registry (NPR) and the NPIC. NPR covers the entire population and is linked to the national reimbursement systems for health services. NPIC is a nationwide service answering questions from the public, healthcare professionals and emergency service about acute poisonings. For every call, the NPIC registers among others age, sex, reason for exposure and substance. This study followed the STROBE reporting guideline. Because the study used aggregated data no ethical approval was required. We used the mid-year population to calculate admission rates of self-poisoning with medication and biological substance (ICD-10 T4n) in 2011–2021 in the two age groups 10–14 and 15–19 years. We included both admission where self-poisoning was registered as the primary diagnosis and as the secondary diagnosis. The same procedure was used to calculate the contact rates to the NPIC in 2011–2022. We estimated predictions intervals for 2020 and 2021 based on either averages or linear trends in admission rates in SHC and contact rates to the NPIC in the period 2011–2019. For contact rates to the NPIC we also estimated predictions intervals for 2022. Figure 1 shows the observed admission rates in SHC and contact rates to the NPIC with prediction intervals for girls aged 10–14 (panel a) and 15–19 (panel b). We did not observe any significant changes in admission rates to SHC and contact with the NPIC from 2019 to the 2020. From 2019 (pre-pandemic) to 2021, the observed admission rates in SHC for selfpoisoning increased with 344% and 220% for girls aged 10–14 and 15–19, respectively. These trends were also evident if we restricted to admissions where selfpoisoning was the primary diagnosis. The observed contact rates to the NPIC increased by 235% and 169%. The contact rates to the NPIC remained elevated in 2022. The increases were statistically significant. Among girls aged 10–14 years, the admission rates to SHC were 71 per 100,000 in 2019 and 243 per 100,000 Received: 19 January 2023 Revised: 27 March 2023 Accepted: 2 April 2023