Rates of acute mental health presentations in youth were increasing pre-pandemic internationally. Longitudinal studies following COVID-19 attest to ongoing deterioration in youth mental health, recognising adverse unintended consequences following public health restrictions.

To examine whether the initial post-COVID-19 increase in mental health presentations persisted following the reclassification of COVID-19 to endemic status, accompanied by the removal of most restrictions.

All referrals to paediatric liaison psychiatry (PLP) between January 2018 and December 2022 in a Dublin tertiary children's hospital were included in the study. An interrupted time series analysis with autoregressive integrated moving average models was conducted, examining referrals with respect to different phases of COVID-19 and application of public health restrictions.

Some 1385 referrals to PLP were received over the 5-year study. There was a significant decrease in PLP referrals immediately post-COVID-19, followed by a significant and sustained increase as the pandemic progressed and moved to endemic status. Public health restriction phases had a unique effect on those presenting with suicidal ideation, with a significant increase in the number of referrals. There was no effect of restrictions on other clinical profiles.

Increased referrals for youth with mental health difficulties, reported during the COVID-19 pandemic, persisted into the early endemic stage, after COVID-19 public health restrictions ceased. Specific impacts of restrictions on suicidal ideation referrals require further study. Investment in child and adolescent mental health services remains a priority, and future pandemic response strategies need to examine unintended consequences of any enforced public health measure.

A review of the literature demonstrates that relatively little is known about acute psychiatric presentations in children (0–12 years), compared with adolescents or young adults (12 years+). This study aims to review psychiatric presentations of children to a CAMHS Liaison Service at Children’s Hospital Ireland (CHI) at Tallaght University Hospital over a 10-year period.

A retrospective study was undertaken of case notes of all children aged 12 years and under who were referred to the CAMHS Liaison Service between January 2009 and December 2018 (n = 318). Data were anonymised and inputted into SPSSv25 for analysis. The relationships between presentations and methods of self-harm over time were measured using Pearson’s correlation. Associations between categorical variables were analysed using chi-squared tests.

There was a significant increase in presentations of under-12s over the 10-year period (r(8)=0.66, p = 0.02). There was also a significant increase in children presenting with a disturbance of conduct and/or emotions over time (r(8) = 0.79, p < 0.001). There was a significant association between female gender and ingestion (X2 = 12.73, df = 1, p < 0.05) and between male gender and ligature as a method of self-harm (X2 = 5.54, df = 1, p < 0.05). Over half (53%) of children presented with suicidal thoughts and 22% presented with suicidal behaviours. The reported use of ligature as a method of self-harm emerged only from 2012 among cases studied.

Children aged 12 years and under are presenting in increasing numbers with acute mental health difficulties, including suicidal thoughts and behaviours. There is a worrying trend in methods of self-harm, particularly in high lethality behaviours such as attempted strangulation.