Major depressive disorder (MDD) is the most common mental illness and is the single leading cause of years lived with disability. Depression that begins early (by the early 20s) predicts particularly poor mental health and social outcomes and a chronic and relapsing course of symptoms over time. The strongest and most common risk factor for early-onset MDD is depression in a parent – this risk is likely to involve both environmental and inherited components.

In this project, we will characterise the trajectory of depressive symptomatology over adolescence and early adult life. We will test whether antecedent risk and protective factors identified in previous work influence the trajectory of symptoms over time. We will develop an algorithm to quantify individual risk for early-onset depression.