Children who experience more positive relationships and supportive environments while growing up are significantly less likely to develop depression or anxiety in early adulthood, according to new research led by RCSI University of Medicine and Health Sciences.

Published in the American Journal of Psychiatry, the study found that positive childhood experiences, such as supportive friendships, trusting relationships with parents and teachers, and feeling safe in the local neighbourhood were linked to better mental health at age 24, even after accounting for other known risk factors.

The relationship held even after researchers accounted for factors known to influence mental health, including childhood trauma, socioeconomic circumstances and genetic predisposition to mental illness. This suggests that positive experiences are more than simply a marker of lower overall risk. Instead, they appear to make an independent contribution to children's long-term mental health, alongside other influences.

Researchers at RCSI and FutureNeuro, the Research Ireland Centre for Translational Brain Science, analysed data from 3,499 children from the Avon Longitudinal Study of Parents and Children (ALSPAC), also known as Children of the 90s, observing positive experiences from birth to age 17. They tracked 10 broad types of positive experience across childhood and adolescence including a good relationship with a parent, a good relationship with a teacher, regular activities outside the home, supportive friendships, feeling safe in the neighbourhood, enjoyment of school and frequent contact with family and friends, then assessed mental health outcomes at age 24.

Participants were scored according to how many positive experiences they had during childhood and adolescence. Those with higher scores, i.e. more positive experiences, were significantly less likely to meet the criteria for depression, anxiety or another psychiatric disorder at age 24. The study used an advanced statistical approach designed to estimate cause and effect as closely as possible using observational data.

The strongest association was seen for depression, with each additional positive experience linked to a lower likelihood of depression in early adulthood. The association with anxiety was smaller but remained statistically significant. Findings for psychosis were inconclusive, as too few participants developed the condition to draw firm conclusions.

Professor David Cotter from the RCSI Department of Psychiatry was senior author on the paper. He said: “We often think about protecting children's mental health in terms of preventing negative experiences, and that's absolutely vital. But children also build supportive relationships and other positive experiences at home, at school and in their communities. Our findings suggest these experiences can all contribute to better mental health as young adults.”

The findings do not suggest that positive experiences erase or outweigh the effects of trauma. Instead, they indicate that positive experiences may provide additional protection for mental health, adding to a growing picture in which mental health in early adulthood is shaped by an accumulation of both risk and protective experiences across childhood – not by any single factor alone.

Dr Jennifer Murphy, first author on the study, said, “Early adulthood is when many mental health conditions first become established, but we still know relatively little about which childhood experiences have the greatest influence on well-being at this stage of life.

“We hope these findings support a stronger focus in schools, health services and parenting support, on building positive experiences for children and young people, rather than concentrating solely on reducing harm.”

Together, the findings suggest that improving children's mental health is likely to require both reducing adversity and increasing opportunities for positive experiences throughout childhood and adolescence. This research was carried out with collaborators from RCSI, University College Dublin, University of Edinburgh, University of Oulu, St John of God Hospitaller Services Group, Northern Health and Social Care Trust, DETECT Early Intervention for Psychosis Service, Trinity College Dublin, St Vincent’s University Hospital and Queen’s University Belfast.

The study was conducted as part of the PSI-STAR PhD psychosis research training programme, funded by the Health Research Board (HRB). This work would not have possible without the generosity of the members of the ALSPAC Cohort, and the ALSPAC academic team from the University of Bristol.