Depressive symptoms and suicidal behaviour: changes with time in an adolescent clinic cohort.

Abstract

There are suggestions of a secular increase in the prevalence of depression, self-harm and suicidal behaviour in young people. This study aims to examine changes in prevalence of psychological disturbance over time in adolescents referred for treatment. Data on the type and severity of emotional and behavioural problems was measured using the Youth Self-Report and Child Behaviour Checklist in 4495 clinic-referred adolescents aged 12-17 years, born in a 21-year period (1966-1986). After taking into account the confounding effects of age and gender, there were significant increases in reports of self-harm and suicidal ideation (5% and 4% increase in odds per year, respectively) according to parents, but there was no change in parental ratings of depression (anxious/depressed scale). There were no changes in ratings of self-harm, suicidal ideation or anxiety/depression when adolescent reports were considered. The mean age at the time of referral decreased with increasing year of birth, from 14.6 years in those born in 1966-1971, to 13.1 years in those born in 1981-1986. Parents of referred adolescents reported increasing self-harm and suicidal behaviour with increasing year of birth. In contrast, there were no changes over time in the adolescents' reports. Neither parents nor children reported an increase in depressive symptoms. Perceptions of a secular increase may reflect increasing parental awareness of some behaviours, particularly self-harm and suicidal ideation. Interpretation of these results needs to be cautious given the clinical origin of the sample.