This study found that young adults with a history of transient PEs experienced longitudinal changes in self-reported educational, vocational and interpersonal difficulties between adolescence and young adulthood. They reported higher levels of adolescent educational/vocational and interpersonal difficulties when compared with young people without a history of PEs. However, by young adulthood these differences were no longer present. The between group convergence in difficulties scores in young adulthood could not be explained by worsening educational/vocational and interpersonal difficulties in the control group, as difficulties were observed to lessen in both groups over time. Additionally, although young people with a history of transient PEs had higher levels of childhood victimization than controls, this did not account for the findings in relation to either interpersonal or educational/vocational difficulties.
The finding of higher levels of educational/vocational difficulties and problematic interpersonal relationships in adolescence is consistent with existing evidence from interviewer-rated functioning deficits in young people with a history of transient PEs (13, 26). As has been found previously, the differences between groups during adolescence could not be fully explained by childhood psychopathology or by childhood victimization (14). However, our young adult findings contrast with existing evidence of functional deficits up to the age of 21 among young people with a history of transient PEs in studies using interviewer-rated measures (13, 26). One potential explanation for this difference is that educational/vocational and interpersonal difficulties associated with transient PEs may themselves be transient and that the post-adolescent period may be a critical time for improvements in difficulties in young people with a history of transient PEs. There is some support for this hypothesis in some limited evidence regarding stress reactivity. In their study, Cullen et al found evidence that children with PEs had both high levels of stress exposure and heightened distress responses (33). However, in their twin study, Collip and colleagues found that adults with transient PEs had lower levels of stress reactivity than those with persistent PEs (34), suggesting that transient PEs may not be a strong indicator of risk for future difficulties and sensitivity to stress in adulthood.
Findings from this study also complement those from the field of resilience research that have demonstrated the remediation effect that positive environmental, relational and personal factors can have on the mental health and functioning of children and adolescents (35). The Kauai Longitudinal Study found that, by mid-life the majority of high risk adolescents, including those with poor mental health, poor coping and delinquency, were functioning well, satisfied with their interpersonal relationships and contributing to their communities (36, 37). Thus, the improvements observed in this study by young adulthood could, at least in part, be explained by the potential for vulnerable youth to catch up with their less vulnerable peers during the early to mid-adult years. There is some support for this hypothesis based on findings from a qualitative study that was undertaken as part of the Adolescent Brain Development (ABD) study (38). The study involved in-depth qualitative interviews with 17 participants (aged 18–21 years), all of whom had reported experiencing early PEs. Findings from that study found that a number of young people with a history of PEs reported high levels of life satisfaction, well-being, educational functioning and positive interpersonal relationships, even in the context of early exposure to childhood adversity, including family stress. What differentiated young people with positive outcomes from those who were struggling was the presence of a supportive adult attachment figure and opportunities to contribute to society, both of which have been found to be protective against poor psychosocial outcomes in life and to nurture resilience (37, 39, 40). The key role that attachment relationships and other protective factors have in supporting positive outcomes in young adulthood in young people with a history of PEs may therefore be relevant in understanding findings in this study. Attachment, for example, has been found to mediate the relationship between early adversity and PEs (41–43) and between adversity and psychological distress and wellbeing (44). Similarly, positive parent-child relationships during adolescence have recently been identified as mediators of the relationship between early adversity and PEs (45) and between PEs and other psychopathology (Healy et al in press) in youth populations. Longitudinal research examining potential mediating role of psychosocial factors in the relationship between PEs and functioning over time could offer further insights into the role of protective factors in the relationship between early adversity, PEs, psychopathology and functioning.
One alternative explanation for our findings is that they reflect a positive self-report bias among participants in this study. Thus, that young adults may have more positive subjective perceptions of their relationships and their educational or vocational experiences than those appraised externally. However, this is not fully supported by the finding of significant differences reported in relation to adolescence. Further research using validated self-report measures of functioning would be useful. Additionally, although there is growing evidence that early PEs may be a marker of functional deficits that cannot be fully explained by the psychopathology, evidence also suggests that the relationship between PEs and functioning may be affected by multiple additional factors that interact dynamically and synergistically. Young people who experience early adolescent PEs have also been found to be at increased risk for a range of later neurocognitive (46), interpersonal (47), attachment (38) and psychopathological (23, 24) difficulties. Each of these could also affect social, educational, vocational and interpersonal functioning. A combination of these factors is likely to increase that risk further. Young people with PEs are also more likely to have a history of childhood adversity and trauma (48–52), which are known to affect brain development (53), social functioning (54, 55), cognitive functioning (56, 57) and mental health generally (58). Conversely, factors such as lower levels of adversity, higher self-esteem and spirituality have been found to be protective against poor outcomes, even among people who have persistent PEs (59). The sample size of the current study precluded the examination of these potential mediators or moderators.
The impact of early adversity is also important when considering findings from this study. Our finding of an almost 3.5 fold increase in the odds of transient PEs for young people who had experienced childhood victimization is consistent with a substantial body of evidence indicating that adversities that which involve an intent to harm are associated with PEs generally (48, 51, 60–62). Similarly, our finding that individuals who reported a greater number of childhood adversities had an almost 1.5 fold increase in the odds of experiencing transient PE complements existing evidence that cumulative exposure to adversity and trauma is associated with an increased risk for any PEs (63, 64). Although not significant, our findings do suggest that family stress may also be a risk factor for the experience of PEs. There is some support for this, with evidence that early experiences within the family environment and interpersonal child-parent relationships are associated with PEs (48) (see also Healy et al, in press). As we were unable to compare our transient PE group with those with recurrent (N = 2) or new onset (N = 5) PEs, it was not possible to determine any associations between early exposure to family stress or death, recurrent or young adult onset PEs and self-reported difficulties in young adulthood in this study. This will require longitudinal studies with larger sample sizes with sufficient power to examine these group differences over time.
The results of this study should be considered in light of both strengths and limitations. Strengths of this study include full clinical interviews, consensus meetings to assess for PEs and the community-based sampling approach which eliminated the risk for bias resulting from health-care seeking behaviour or snowball sampling. Limitations include small sample size and consequently greater potential for type II error. The small sample size also precluded us from comparing those with transient PEs with individuals with recurrent or new onset PEs, which would have enhanced the study considerably. Furthermore, the SLES enquired about life events and functioning both currently and retrospectively, potentially decreasing the accuracy of some of the responses.