Type D personality in the general population:a systematic review of health status, mechanisms of disease, and work-related problems

BACKGROUND: The objective was to review all available literature concerning Type D (distressed) personality among the general population and to discuss its implications for research on health status, disease-promoting mechanisms and work-related problems in non-clinical populations. METHODS: A computerized search of the literature was performed independently and in duplicate by both investigators on December 21(st), 2009. Published research reports were included if they studied Type D personality among the general population. Nineteen articles were selected and they were subjected to an 11-item standardised quality checklist by both investigators. RESULTS: The methodological quality of the selected studies was adequate to high. The studies included in this review showed that the presence of Type D characteristics had a negative impact on mental health status (more symptoms of depression, anxiety, post-traumatic stress disorder, mental distress, passive coping, and less social support) and physical health status (more somatic complaints, lower health status, more influenza-like illness reporting). Other studies reported on behavioral and biological mechanisms of disease in apparently healthy individuals with a Type D personality. Finally, some studies also showed a negative effect of Type D personality on work-related problems (higher absence-leave, higher levels of vital exhaustion and burnout, and more work-related stress). CONCLUSIONS: Type D personality is a vulnerability factor for general psychological distress that affects mental and physical health status and is associated with disease-promoting mechanisms and work-related problems in apparently healthy individuals

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

AbstractBackgroundType 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.ObjectivesThe 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.MethodsWe 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.ResultsAt 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).ConclusionsChoice 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

Heritability of type-D personality.

OBJECTIVE: To quantify the influence of genes and environment on individual differences in type-D status, and the type-D subcomponents negative affectivity and social inhibition. Type-D personality independently predicts poor prognosis in patients with cardiovascular disease. However, no previous study has determined the heritability of type-D personality. METHODS: This study determined type-D personality by applying the "combination of scales" method to survey data collected by the Netherlands Twin Register in 3331 healthy, young adult twins. Using structural equation modeling (SEM), the relative contributions of additive genetic, nonadditive genetic, and nonshared environmental factors to the variance in type-D and its subcomponents were determined. RESULTS: SEM indicated that type-D personality was substantially heritable (52%). The subcomponents negative affectivity and social inhibition were equally heritable, with broad heritability estimates of 46% and 50%. Although negative affectivity was determined by additive genetic effects and nonshared environment, individual differences in social inhibition were predominantly determined by nonadditive genetic effects and nonshared environment. CONCLUSIONS: This study provides strong evidence that genes are important in determining individual differences in type-D personality and the type-D subcomponents negative affectivity and social inhibition. Copyright © 2007 by American Psychosomatic Society