Stress and the heart

Stress and the heart

Stress can have direct biological effects e.g. physical strain, hormonal changes, maladaptive coping behaviour e.g. smoking, drinking alcohol as well as emotionally mediated effects on diet and activity level. Cumulative stress due to repeated stressful events over time without de-stressing or healing can erode coping mechanisms and cause break down. The important stress hormones are the corticosteroids and catecholamines (adrenaline and nor-adrenaline). Effects of catecholamines include increase in heart rate, cardiac force of contraction, narrowing of blood vessels, increase in blood pressure and increase platelet adherence or ‘stickiness’.

Job stress and risk of coronary artery disease

In a study involving 6895 men and 3413 women between the ages of 35 – 55 years, with a follow up period of 5.3 years, an imbalance between personal efforts and rewards were associated with a 2.15  times risk of new coronary artery disease. Especially, low job control was strongly associated with new disease [Bosma PH, et al, Am J Public Health, 1998; 88:68-74].

Effort-reward imbalance

Risk is increased when workplace effort is not commensurate with tangible – eg salary or intangible -support rewards which the person receives for the effort. Effort-reward imbalance predicts the incidence of cardiac events, even after adjustment for other risk factors. There is an inverse relationship between job satisfaction and myocardial infarction. The mechanisms may be mediated by increases of total cholesterol levels and declines of HDL-cholesterol level, which leads to progression of atherosclerotic lesions and also through an increase of catecholamine release.