Psychological stress and incidence of ischaemic heart disease

BACKGROUND: We assessed the relationship between psychological stress and ischaemic heart disease (IHD) incidence in a population of 868 men over a 10-year follow-up period. METHODS: In 1981, 869 men aged 42-60, free from IHD and living around Quebec City completed a questionnaire assessing the presence of psychological stress in different areas of their life. They also underwent a medical examination and provided information on IHD risk factors. From 1981 to 1991, the incidence of IHD events was ascertained. The relationship between 13 stress dimensions and IHD incidence was investigated using Cox regression while controlling for important IHD risk factors. Cross-sectional analyses were also performed to investigate the relationship between stress dimensions and IHD risk factors. RESULTS: Between 1981 and 1991, 79 men (9%) experienced a first IHD event. The following risk factors were associated with the risk of IHD: age, (rate ratio (RR) = 1.93, 95% CI: 1.21-3.09), hypertension (RR = 1.90, 95% CI: 1.22-2.98), triglycerides (RR = 1.87, 95% CI: 1.19-2.95) and high density lipoprotein (HDL) cholesterol (RR = 1.64, 95% CI: 1.05-2.55). After controlling for risk factors, not one of the psychological stress dimensions significantly altered the risk of IHD. CONCLUSIONS: While confirming the influence of hypertension, age, triglycerides and HDL cholesterol on IHD incidence, this study suggests that there is no important connection between the explored stress dimensions and IHD incidence. It is unlikely that this lack of association is due to the stress questionnaire since the 13 stress dimensions were rigorously developed through independent evaluation of the questions by three specialists and many statistically significant relationships were observed between stress dimensions and IHD risk factors.