Psychosocial resilience in adolescent offspring of mothers with depression: testing causal mechanisms

Adolescent emotional and behavioural problems have become increasingly common. A key priority is to identify causal risk and protective mechanisms to inform policies and prevention strategies, especially in high-risk groups. A common contributory factor is exposure to maternal depression that can have a major impact on the development, health and wellbeing of children, especially when a mother's depression is chronic or recurrent. Problems often develop during adolescence and include depression, antisocial behaviour and difficulties at home and at school. However, maternal depression affects children in different ways. Many young people with a depressed mother do not develop behavioural or emotional problems and instead remain well-adjusted. This study tests the role that young people themselves, their families and friends play in promoting resilient adaptation to maternal depression as a risk influence. Is resilience more likely when a parent's depression does not interfere with effective parenting or when harmonious family relationships are maintained? Are children's own resources important, for example having effective coping strategies? Can positive relationships with friends compensate for difficulties at home? Understanding what best helps young people with depressed parents maintain positive psychosocial wellbeing as they grow up is important as this will facilitate identification of effective intervention targets. However, it is crucial to show that resilience promoting factors are associated with sustained protective effects, to consider whether they also predict change in well-being (e.g. recovery from earlier problems), to test the direction of effects thereby clarifying 'causal' mechanisms involved in resilience. To find out the causal pathways involved requires good understanding of how resilience in young people develops over time. This project makes use of two extremely valuable longitudinal datasets and analyses. The first is a large population cohort of parents and children studied from birth into adolescence. The second is a sample of parents with recurrent clinical depression. Both studies have followed parents and their children as they grow older. This means that analyses can begin to disentangle underlying causal processes by modelling how change in young people's mental health is related to change in the factors that promote resilience (and vice versa). The study will also address a number of other important issues. We will make sure that child, family and peer relationship factors that might form the targets for intervention are not just markers for correlated adversity. We will test which protective factors are specifically important in the context of maternal depression. The study will address whether different factors are important for boys and for girls, because this will later help tailor interventions appropriately. Finally, we will test whether explanations for resilience in young people affected by chronic maternal depressive symptoms in the general population are the same as for a sample of adolescents with more severely affected mothers with recurrent depressive disorder.

One in ten young people suffer from significant emotional and behavioural disorders, and suicide is the third leading cause of death in teenagers and young adults. Moreover, evidence highlights that such problems have become more common in recent years. Youth depression and antisocial behaviour show strong continuities with adult psychosocial adjustment, and have broad consequences for young people's life chances, including education, work and family life. It is therefore a key social, economic and health priority to develop policies and practical interventions that reduce the incidence and burden of adolescent psychopathology. Epidemiological and clinical studies show that adolescents of depressed mothers are at an especially high risk of depression, conduct disorder, substance use, self harm and suicide. However, problematic outcomes are not inevitable for these young people as there is considerable variation in functional adaptation within this high risk group. It is striking that many adolescents appear remarkably resilient even when their mother suffers from chronic and severe depression. Having identified maternal depression as an important risk factor we now need to move forward by establishing what psychosocial factors promote adaptive adolescent developmental trajectories. Crucially, developmental processes and mechanisms that explain resilience remain poorly understood. The identification of modifiable protective mechanisms of relevance to this at-risk group will inform local and national policy and appropriate targets for preventative interventions. However, it is first necessary to be sure that identified protective factors result in sustained positive developmental trajectories, to better understand the causal mechanisms involved, and to ensure that findings are robust across different samples and population subgroups.

Specific beneficiaries of our research will include intervention experts and policy makers. We will work closely with those designing intervention programmes for young people living with mothers who are depressed. They will benefit by being informed of appropriate targets for new preventive strategies aimed at enhancing resilience. Policy-makers will also benefit directly from this research. Much research appropriately highlights the risks for offspring of depressed parents. Understanding promoters of resilience will provide a useful complement in making decisions about putting in place efforts to support these high risk adolescents, both locally and nationally. We will continue our work with the Dartington Social Research Unit (DSRU). For example, the PI is currently involved in work by the DSRU who are partnering several local authorities to test out innovative approaches to use evidence to shape children's services. We aim to use similar strategies to translate understanding of specific targets for promoting adolescent resilience based on a strong empirical and replicated evidence base into effective future policy and practice. This in turn makes it more likely that the research will have longer term benefits for young people affected by parental depression through improved access to effective interventions and services. This has the potential to benefit young people's immediate and long-term psychosocial functioning. Promoting resilient psychosocial trajectories in adolescents will have positive consequences for society as a whole by reducing the burden of economic and social costs associated with depression and antisocial behaviour.