The prognosis of common mental disorders in adolescents: a 14-year prospective cohort study.
BACKGROUND
Most adults with common mental disorders report their first symptoms before 24 years of age. Although adolescent anxiety and depression are frequent, little clarity exists about which syndromes persist into adulthood or resolve before then. In this report, we aim to describe the patterns and predictors of persistence into adulthood.


METHODS
We recruited a stratified, random sample of 1943 adolescents from 44 secondary schools across the state of Victoria, Australia. Between August, 1992, and January, 2008, we assessed common mental disorder at five points in adolescence and three in young adulthood, commencing at a mean age of 15.5 years and ending at a mean age of 29.1 years. Adolescent disorders were defined on the Revised Clinical Interview Schedule (CIS-R) at five adolescent measurement points, with a primary cutoff score of 12 or higher representing a level at which a family doctor would be concerned. Secondary analyses addressed more severe disorders at a cutoff of 18 or higher.


RESULTS
236 of 821 (29%; 95% CI 25-32) male participants and 498 of 929 (54%; 51-57) female participants reported high symptoms on the CIS-R (≥12) at least once during adolescence. Almost 60% (434/734) went on to report a further episode as a young adult. However, for adolescents with one episode of less than 6 months duration, just over half had no further common mental health disorder as a young adult. Longer duration of mental health disorders in adolescence was the strongest predictor of clear-cut young adult disorder (odds ratio [OR] for persistent young adult disorder vs none 3.16, 95% CI 1.86-5.37). Girls (2.12, 1.29-3.48) and adolescents with a background of parental separation or divorce (1.62, 1.03-2.53) also had a greater likelihood of having ongoing disorder into young adulthood than did those without such a background. Rates of adolescent onset disorder dropped sharply by the late 20s (0.57, 0.45-0.73), suggesting a further resolution for many patients whose symptoms had persisted into the early 20s.


CONCLUSIONS
Episodes of adolescent mental disorder often precede mental disorders in young adults. However, many such disorders, especially when brief in duration, are limited to the teenage years, with further symptom remission common in the late 20s. The resolution of many adolescent disorders gives reason for optimism that interventions that shorten the duration of episodes could prevent much morbidity later in life.


BACKGROUND
Australia's National Health and Medical Research Council.
Department of Paediatrics, University of Melbourne, Parkville, VIC, Australia; Centre for Adolescent Health, Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, VIC, Australia. Electronic address: george.patton@rch.org.au.
George C
GC
Patton
Centre for Adolescent Health, Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, VIC, Australia.
Carolyn
C
Coffey
Department of Paediatrics, University of Melbourne, Parkville, VIC, Australia; Clinical Epidemiology and Biostatistics Unit, Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, VIC, Australia.
Helena
H
Romaniuk
Orygen Youth Health Research Centre, University of Melbourne, Parkville, VIC, Australia.
Andrew
A
Mackinnon
Department of Paediatrics, University of Melbourne, Parkville, VIC, Australia; School of Population and Global Health, University of Melbourne, Parkville, VIC, Australia; Clinical Epidemiology and Biostatistics Unit, Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, VIC, Australia.
John B
JB
Carlin
School of Population and Global Health, University of Melbourne, Parkville, VIC, Australia; National Drug and Alcohol Research Centre, University of New South Wales, NSW, Australia.
Louisa
L
Degenhardt
Department of Paediatrics, University of Melbourne, Parkville, VIC, Australia; Psychological Sciences, University of Melbourne, Parkville, VIC, Australia; Centre for Adolescent Health, Murdoch Children's Research Institute, Royal Children's Hospital, Parkville, VIC, Australia; School of Psychology, Deakin University, Geelong, VIC, Australia.
Craig A
CA
Olsson
Institute of Psychiatry, Health Service and Population Research Department, King's College London, London, UK.
Paul
P
Moran
D000293:Adolescent; D000328:Adult; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000453:epidemiology*; D011379:Prognosis; D011446:Prospective Studies; D012307:Risk Factors; D014739:Victoria / Q000453:epidemiology; D055815:Young Adult