There have been many studies on the effect of stress on people. In short, it's bad for them. Much less research has been done on the effect of a patient's outlook on his or her medical outcome. A recent study done at Brown University indicates that having a positive outlook can improve that outcome. The results of the study were published in the July/August issue of the Annals of Family Medicine. Men who felt they were at average risk for heart disease had a death rate from cardiovascular disease triple that of those who felt they were only at low risk. This effect was not seen in women. The study took place over a 15 year period.
The message here is definitely not, ‘Don't worry, be happy.’