Explaining heterogeneity in the predictive value of Type D personality for cardiac events and mortality

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. Objectives: 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 >5 years follow-up: major adverse cardiac events (MACE), cardiac death/MI, and non-cardiac death. Patients were classified in 4 age categories: <50 y, 50-59 y, 60-69 y and >= 70 y. 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 = 70 y (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 >= 70 y. Research on psychosocial risk in CAD should account for different sources of heterogeneity in study characteristics. (C) 2016 The Authors. Published by Elsevier Ireland Ltd.