title: Longitudinal modelling of theory-based depressive vulnerabilities, depression trajectories and poor outcomes post-ACS.
abstract: BACKGROUND
  Depression is associated with increased mortality in patients with acute coronary syndrome (ACS). However, little is known about the theoretical causes of depression trajectories post-ACS, and whether these trajectories predict subsequent morbidity/mortality. We tested a longitudinal model of depressive vulnerabilities, trajectories and mortality.
  
  
  METHODS
  A prospective observational study of 374 ACS patients was conducted. Participants completed questionnaires on theoretical vulnerabilities (interpersonal life events, reinforcing events, cognitive distortions, and Type D personality) during hospitalisation and depression at baseline and 3, 6 and 12 months post-hospitalisation. Latent class analysis determined trajectories of depression. Path analysis was used to test relationships among vulnerabilities, depression trajectories and outcomes (combination of 1-year morbidity and 7-year mortality).
  
  
  RESULTS
  Vulnerabilities independently predicted persistent and subthreshold depression trajectory categories, with effect sizes significantly highest for persistent depression. Both subthreshold and persistent depression trajectories were significant predictors of morbidity/mortality (e.g. persistent depression OR=2.4, 95% CI=1.8-3.1, relative to never depressed).
  
  
  CONCLUSIONS
  Causality cannot be inferred from these associations. We had no measures of history of depression or treatments, which may affect associations.
  
  
  CONCLUSIONS
  Theoretical vulnerabilities predicted depression trajectories, which in turn predicted increased morbidity/mortality, demonstrating for the first time a potential longitudinal chain of events post-ACS. This longitudinal model has important practical implications as clinicians can use vulnerability measures to identify those at most risk of poor outcomes.
authors.affiliation: Centre for Health Policy & Management, Trinity College Dublin, 3-4 Foster Place, College Green, Dublin 2, Ireland.
authors.forename: Conor
authors.initials: C
authors.lastname: Keegan
authors.affiliation: Division of Population of Health Sciences, Royal College of Surgeons in Ireland, 123 St. Stephen's Green, Dublin 2, Ireland.
authors.forename: Ronán
authors.initials: R
authors.lastname: Conroy
authors.affiliation: Division of Population of Health Sciences, Royal College of Surgeons in Ireland, 123 St. Stephen's Green, Dublin 2, Ireland. Electronic address: fdoyle4@rcsi.ie.
authors.forename: Frank
authors.initials: F
authors.lastname: Doyle
mesh_terms: D054058:Acute Coronary Syndrome / Q000150:complications / Q000401:mortality / Q000523:psychology*; D003863:Depression / Q000150:complications / Q000175:diagnosis* / Q000401:mortality / Q000523:psychology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008960:Models, Psychological; D011379:Prognosis; D011446:Prospective Studies
keywords: Coronary heart disease; Depression; Depressive trajectories; Depressive vulnerabilities; Psychological theory