title: The stability and change of etiological influences on depression, anxiety symptoms and their co-occurrence across adolescence and young adulthood.
abstract: BACKGROUND
  Depression and anxiety persist within and across diagnostic boundaries. The manner in which common v. disorder-specific genetic and environmental influences operate across development to maintain internalizing disorders and their co-morbidity is unclear. This paper investigates the stability and change of etiological influences on depression, panic, generalized, separation and social anxiety symptoms, and their co-occurrence, across adolescence and young adulthood.
  
  
  METHODS
  A total of 2619 twins/siblings prospectively reported symptoms of depression and anxiety at mean ages 15, 17 and 20 years.
  
  
  RESULTS
  Each symptom scale showed a similar pattern of moderate continuity across development, largely underpinned by genetic stability. New genetic influences contributing to change in the developmental course of the symptoms emerged at each time point. All symptom scales correlated moderately with one another over time. Genetic influences, both stable and time-specific, overlapped considerably between the scales. Non-shared environmental influences were largely time- and symptom-specific, but some contributed moderately to the stability of depression and anxiety symptom scales. These stable, longitudinal environmental influences were highly correlated between the symptoms.
  
  
  CONCLUSIONS
  The results highlight both stable and dynamic etiology of depression and anxiety symptom scales. They provide preliminary evidence that stable as well as newly emerging genes contribute to the co-morbidity between depression and anxiety across adolescence and young adulthood. Conversely, environmental influences are largely time-specific and contribute to change in symptoms over time. The results inform molecular genetics research and transdiagnostic treatment and prevention approaches.
authors: King's College London,MRC Social, Genetic and Developmental Psychiatry Centre,Institute of Psychiatry, Psychology and Neuroscience,London,UK.
authors: M A
authors: MA
authors: Waszczuk
authors: King's College London,MRC Social, Genetic and Developmental Psychiatry Centre,Institute of Psychiatry, Psychology and Neuroscience,London,UK.
authors: H M S
authors: HM
authors: Zavos
authors: Department of Psychology,Goldsmiths,University of London,London,UK.
authors: A M
authors: AM
authors: Gregory
authors: King's College London,MRC Social, Genetic and Developmental Psychiatry Centre,Institute of Psychiatry, Psychology and Neuroscience,London,UK.
authors: T C
authors: TC
authors: Eley
mesh_terms: D000293:Adolescent; D000328:Adult; D001008:Anxiety Disorders / Q000209:etiology* / Q000235:genetics; D001010:Anxiety, Separation / Q000209:etiology / Q000235:genetics; D003866:Depressive Disorder / Q000209:etiology* / Q000235:genetics; D005260:Female; D059647:Gene-Environment Interaction; D006801:Humans; D008297:Male; D016584:Panic Disorder / Q000209:etiology / Q000235:genetics; D010698:Phobic Disorders / Q000209:etiology / Q000235:genetics; D035781:Siblings; D055815:Young Adult
keywords: Adolescence; anxiety; depression; development; generalized anxiety; genetics; panic; separation anxiety; social anxiety; twins; young adulthood