Objective: To study the relation between measures of personality and risk of cardiovascular disease and cancer in a large cohort.
Design: Follow-up of population based cohort.
Setting: Heidelberg, Germany.
Participants: 5114 women and men aged 40-65 in 1992-5.
Main outcome measures: Psychological traits assessed by several standardised personality questionnaires in 1992-5, related to cause of death (to 2002-3) or reported incidence of cardiovascular diseases and cancer (validated by treating doctors). Relative risks (and 95% confidence intervals) for combined morbidity and mortality according to five important personality traits were estimated using multivariable Cox proportional hazards models.
Results: During median follow-up of 8.5 years, 257 participants died and 72 were diagnosed with a heart attack, 62 with stroke, and 240 with cancer (morbidity and mortality combined). A high internal locus of control over disease was associated with a decreased risk of myocardial infarction (adjusted relative risk for an increase of 1 SD = 0.75; 95% confidence interval 0.58 to 0.96). An increase of 1 SD in time urgency was associated with a decreased risk of cancer (adjusted relative risk 0.83; 0.73 to 0.95). Other major personality traits--anger control, psychoticism, and symptoms of depression--were not consistently associated with myocardial infarction, stroke, or cancer.
Conclusion: Internal locus of control over disease and time urgency seem to be associated with reduced risk for common chronic diseases, probably by affecting unmeasured health related behaviour. The other personality traits assessed had no major impact on cardiovascular disease and cancer.