The blood pressure increases, the pulse rate increases and over a long period of time, the immune system begins to falter. This would explain why individuals who are under a lot of stress become ill more frequently than usual. An example would be college students studying for finals. They tend to have a high incidence of colds and other infections. This is because they stay up late at night and put their bodies through a lot of stress.
Stress can also play a part in the development of heart disease.
The high adrenaline state accelerates the development of heart disease. The blood tends to clot more rapidly. This would explain why individuals subjected to an acute stressful event can have a heart attack. They almost always have underlying heart disease. Symptoms of Stress 1.