Depression in young people often goes undetected.

Major (unipolar) depression is one of the most common mental health disorders in children and adolescents, with an estimated one year prevalence of 4-5% in mid-late adolescence. Depression is probably the single most important risk factor for teenage suicide, the second to third leading cause of death in this age group and a forerunner of adult depressive disorder. Half of those with lifelong recurrent depression started to develop their symptoms before the age of 15 years. Family history is a well established risk factor and children born to depressed parents face three to four times increased rates of depression. Both genetic and environmental factors contribute to this risk. Adolescent girls are more vulnerable to depression in a ratio of 2:1. However, prepubertal depression has an equal sex ratio and is thought to be more strongly related to family dysfunction. Low mood is the predominant feature and depressed children might also have various unexplained physical symptoms, eating disorders, school refusal or substance misuse. Two thirds of adolescents with depression are thought to have at least one comorbid psychiatric disorder, most commonly the range of anxiety disorders, disruptive behavioural disorders and substance misuse problems. NICE highlights the importance of active listening and conversational techniques in order to screen for mood disorders effectively. The key questions used for screening are from the PHQ-2.