Association between childhood adversity and substance use in early adulthood
In 2022, the HRB in collaboration with Trinity College Dublin (TCD) began work analysing a longitudinal study of substance use among young people. HRB Research Officer Dr Deirdre Mongan provides an overview of the study and its progress to date.
4 min read - 8 May 2025
Substance use is one of the most prominent health and social concerns in respect of young people. Adolescence is the peak period during which people first engage in alcohol and/or drug use.
Among 10–24-year-olds, alcohol is the second leading risk factor for disease and injury and drug use is the sixth. Initiation of substance use during this critical period can disrupt significant life transitions and has been linked to detrimental short- and long-term health as well as adverse social consequences.
National drugs strategy
In light of this, the Department of Health – under the national drugs strategy – tasked the HRB with analysing GUI data to gain insights into substance use behaviours among young people.
Trinity College’s Population Health Medicine division, led by Professor Noel McCarthy, was successful in the tender issued by the HRB to develop statistical methodologies and analyse and report on data collected on substance use by children and young people from the Growing Up in Ireland longitudinal study.
Growing Up in Ireland
Growing Up in Ireland (GUI) is the national longitudinal study of children and young people. Its aim is to chart the development of children over time and to examine their progress and wellbeing at critical periods from birth to adulthood.
It also aims to explore the many and varied factors that contribute to or undermine the wellbeing of children currently living in Ireland.
The longitudinal design enabled HRB/TCD researchers to explore individual-level changes, risk factors, and causal inferences, such as how parental and child characteristics at an early age influence substance use later in life.
GUI consists of two cohorts:
- Cohort ’98, which began with 8,500 9-year-old children in 2008
- Cohort ’08, which began with over 11,000 9-month-olds in 2008
HRB/TCD analysis of GUI data
Prior to analysis of GUI data, a scoping review was undertaken by TCD to summarise existing longitudinal research on factors and outcomes related to youth drug and alcohol use to gain insight and identify research gaps from existing evidence.
The review also evaluated methodologies commonly used in longitudinal datasets and informed the subsequent analyses conducted by the HRB and TCD.
The HRB/TCD analysis is based on the 1998 cohort which started in 2008 with 8,500 children aged 9 years.
This cohort was revisited and interviewed at age 13, 17/18 and 20 years. Information was collected from the children/young people themselves, parents/guardians, and from their primary and post-primary school teachers.
The results identify individual, social, and structural risk factors associated with substance use, including: adverse childhood experiences, familial and peer substance use, psychological vulnerabilities, and socio-economic deprivation.
The application of theoretical frameworks to longitudinal analyses enables researchers to better identify and quantify the impact of these risk factors.
By engaging with policymakers and practitioners, the project will inform evidence-based interventions that can mitigate substance use harm and enhance the ability of services to address current and future challenges.
Webinars
Over the course of this year, the HRB will be hosting webinars to discuss the findings of this work, which have already been published, or will be published in 2025 – and potentially 2026.
The first webinar takes place on Tuesday, 13 May at 11am entitled Substance use and childhood adversity, register here.
This free event will feature a presentation by Dr Deirdre Mongan, HRB and a Q&A session with an expert panel composed of Dr Mongan, Richie Stafford from the Department of Health and Professor Ross MacMillan of University of Limerick.
A second webinar on other published reports is due to take place in October.
Growing Up in Ireland is a joint project of the Department of Children, Equality, Disability, Integration and Youth and the Central Statistics Office.
Published papers from the HRB study to date
Acknowledgment
Growing Up in Ireland (GUI) is funded by the Government of Ireland. GUI is managed as a partnership between the Department of Children, Equality, Disability, Integration and Youth (DCEDIY) and the Central Statistics Office (CSO). The CSO is responsible for the survey element of GUI. Results in these reports are based on analyses of data from Research Microdata Files provided by the CSO. Neither the CSO nor DCEDIY take any responsibility for the views expressed or the outputs generated from these analyses.
4 min read - 8 May 2025
