As college students, we are all familiar with stress. Cramming for big exams, deciding what to major in, or even smaller things like blog entry deadlines may be sources of stress in your life. Although uncommon as of now, another ailment will eventually affect many of us as we age. Of course, I'm talking about atherosclerosis and heart disease, more specifically Coronary Heart Disease (CHD). CHD is complete or partial closure of the arteries that supply the heart tissue with oxygen (shown in first image), and is the number one cause of death and disability in the U.S. The disconcerting truth is that stress and CHD are related, and daily stressors have been shown to accumulate in effect over time, so the stress we are experiencing now in college may have more serious implications for our health in old age. Scientific research has shown a correlational relationship between stress and CHD, but further investigation has shown light on the possibility of personality characteristics as the primary risk factor for CHD and coronary events. These two sets of data prompted me to ask the question: Does stress really only have a correlational relationship with CHD?
The Type A Personality
According to Lilienfeld et al., two cardiologists, Meyer Friedman and Ray Rosenman (1959), coined the term "Type A personality" and made an investigation on whether or not traits of this personality type predicted risk of CHD. Some traits of the Type A personality are competitiveness, ambitiousness, impatience, proneness to hostility, stubbornness, etc. The study that Friedman and Rosenman ran showed that even when the classic risk factors for CHD were taken into account, Type A traits were still associated with later heart disease risk. However, these results were not neatly replicated in later studies, in which the scientists actually observed negative results compared to Friedman and Rosenman. This prompted the scientists to question if it is the mosaic of Type A traits that caused the early effects observed, or if it is specific Type A traits that are most associated with CHD.
There is one Type A trait that seems to stand alone in its ability to predict risk of CHD, and that is hostility. In one study, medical students were tested for a hostility score and then tracked down 25 years later to observe a possible association between the personality trait and CHD. The results of the study showed that subjects with high hostility scores were more likely to have suffered from or died from CHD than students with low hostility scores. However, a confounding factor in this association concept is the well-known association of hostility with classic CHD risk factors such as weight gain, smoking and alcohol consumption. This resulted in the formation of an alternative hypothesis - that the effects of hostility on CHD are indirect. When this was tested in a study of older white men, hostility was a better risk factor in predicting CHD than any of the previously mentioned classic risk factors.
Test your own hostility by taking this hostility questionnaire
The data that support hostility as a primary risk factor for CHD appear to satisfy the requirements for a thorough scientific study, encompassing many of the methods to combating the sins of pseudoscience mentioned in Chapter 1. Furthermore, the scientific progression of the study from stress and its overall relation to health all the way to determining how detrimental a single personality trait can be one's health indicates a well-studied subject, as well as comprehensive peer review and generation of competing alternative hypotheses.
One aspect of these studies that I would like to see expansion on is in the breakdown of hostility. Hostility does not seem to be a highly specific term because it could stem from anger, or other emotions such as jealousy or mental illness. The clear definition of this term is essential to the advancement of these hypotheses to a level of clinically applicable knowledge that can arrest or reverse its effect on a patient's health. It would also be interesting to see what effects various types of coping behaviors have on hostility, and if hostility is a product of everyday stressors, or stressful life events.
In closing, I would just like to remind you, the reader, that stress can cumulate and manifest as many forms of illness, not just the CHD discussed in this blog. As always, the advice to eat a healthy, low fat diet and exercise routinely remains.