title: Cognitive content specificity in anxiety and depressive disorder symptoms: a twin study of cross-sectional associations with anxiety sensitivity dimensions across development.
abstract: BACKGROUND
  The classification of anxiety and depressive disorders has long been debated and has important clinical implications. The present study combined a genetically sensitive design and multiple time points to investigate cognitive content specificity in anxiety and depressive disorder symptoms across anxiety sensitivity dimensions, a cognitive distortion implicated in both disorders.
  
  
  METHODS
  Phenotypic and genetic correlations between anxiety sensitivity dimensions, anxiety and depressive disorder symptoms were examined at five waves of data collection within childhood, adolescence and early adulthood in two representative twin studies (n pairs = 300 and 1372).
  
  
  RESULTS
  The physical concerns dimension of anxiety sensitivity (fear of bodily symptoms) was significantly associated with anxiety but not depression at all waves. Genetic influences on physical concerns overlapped substantially more with anxiety than depression. Conversely, mental concerns (worry regarding cognitive control) were phenotypically more strongly associated with depression than anxiety. Social concerns (fear of publicly observable symptoms of anxiety) were associated with both anxiety and depression in adolescence. Genetic influences on mental and social concerns were shared to a similar extent with both anxiety and depression.
  
  
  CONCLUSIONS
  Phenotypic patterns of cognitive specificity and broader genetic associations between anxiety sensitivity dimensions, anxiety and depressive disorder symptoms were similar at all waves. Both disorder-specific and shared cognitive concerns were identified, suggesting it is appropriate to classify anxiety and depression as distinct but related disorders and confirming the clinical perspective that cognitive therapy is most likely to benefit by targeting cognitive concerns relating specifically to the individual's presenting symptoms across development.
authors: Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry,King's College London,UK.
authors: H M
authors: HM
authors: Brown
authors: Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry,King's College London,UK.
authors: M A
authors: MA
authors: Waszczuk
authors: Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry,King's College London,UK.
authors: H M S
authors: HM
authors: Zavos
authors: Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry,King's College London,UK.
authors: M
authors: M
authors: Trzaskowski
authors: Department of Psychology, Goldsmiths,University of London,UK.
authors: A M
authors: AM
authors: Gregory
authors: Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry,King's College London,UK.
authors: T C
authors: TC
authors: Eley
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001008:Anxiety Disorders / Q000453:epidemiology / Q000523:psychology*; D002648:Child; D003072:Cognition Disorders / Q000453:epidemiology / Q000523:psychology*; D015897:Comorbidity; D003430:Cross-Sectional Studies; D003866:Depressive Disorder / Q000453:epidemiology / Q000523:psychology*; D005260:Female; D005838:Genotype; D006803:Human Development; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D010641:Phenotype; D012919:Social Behavior; D011795:Surveys and Questionnaires; D014427:Twins / Q000523:psychology* / Q000706:statistics & numerical data; D055815:Young Adult