title: Explaining heterogeneity in the predictive value of Type D personality for cardiac events and mortality.
abstract: BACKGROUND
  Type D personality has been associated with adverse outcomes in patients with coronary artery disease (CAD). However, large heterogeneity exists between Type D studies, including some studies reporting null-findings.
  
  
  OBJECTIVE
  The aim of this study was to examine i) choice of endpoint and ii) age as two study characteristics that may partly explain this large heterogeneity in the Type D associated prognostic effect.
  
  
  METHODS
  We used four existing data cohorts of 1503 CAD patients (89% male, mean age=57.2±9.1) with baseline measures of Type D and endpoints >5years follow-up: major adverse cardiac events (MACE), cardiac death/MI, and non-cardiac death. Patients were classified in 4 age categories: <50y, 50-59y, 60-69y and ≥70y. Multiple logistic regression models included age, sex, and clinical covariates.
  
  
  RESULTS
  At follow-up, there were 295 events, including 116 cardiac death/MI, and 37 non-cardiac deaths. Both continuous and categorical measures of Type D predicted adverse events. Type D was independently associated with MACE (OR=1.82; 95%CI 1.33-2.50) and cardiac death/MI (OR=2.49; 95%CI 1.55-3.99). However, Type D was not associated with non-cardiac death (OR=1.23; 95%CI 0.57-2.69). Regarding age, Type D consistently predicted MACE in the lower age groups (all ORs≥2.20, all ps≤.004), but not in patients aged ≥70y (OR=1.43, p=.57).
  
  
  CONCLUSIONS
  Choice of endpoint and age modulated the risk conferred by Type D personality. Type D was associated with an increased risk of cardiac events, but not with non-cardiac death, or with events in patients aged ≥70y. Research on psychosocial risk in CAD should account for different sources of heterogeneity in study characteristics.
authors.affiliation: CoRPS - Center of Research on Psychology in Somatic diseases, Tilburg University, The Netherlands. Electronic address: h.m.kupper@tilburguniversity.edu.
authors.forename: Nina
authors.initials: N
authors.lastname: Kupper
authors.affiliation: CoRPS - Center of Research on Psychology in Somatic diseases, Tilburg University, The Netherlands.
authors.forename: Johan
authors.initials: J
authors.lastname: Denollet
mesh_terms: D000367:Age Factors; D000368:Aged; D001526:Behavioral Symptoms / Q000503:physiopathology; D003324:Coronary Artery Disease / Q000175:diagnosis / Q000401:mortality / Q000523:psychology; D003643:Death; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011580:Psychological Techniques; D012307:Risk Factors; D064415:Type D Personality
keywords: Age; Heterogeneity; Moderators; Mortality; Risk prediction; Type D personality