picture from disease in youth. The diseases of youth ordinarily arise from an infecting organism, have an abrupt and obvious beginning, obvious symptoms, and specific, identifiable causative agents. They run a rapid, self-limiting, and self-immunizing course, and have few and minor sequelae. The diseases of old age, on the other hand, ordinarily do not arise from infection (tuberculosis and pneumonia are exceptions) but are due to multiple, obscure factors. Often the disease process begins insidiously and slowly, so that the individual is not aware of it until it is far advanced. It progresses slowly but persistently, does not immunize but instead makes the patient more vulnerable to other diseases, and tends to have important or severe sequelae.62
The course and treatment of disease in old age are influenced by the physical phenomena of senescence and the general slowing up of bodily functions which accompanies aging. Thus, there are a diminished speed and vigor of reaction to injury; a slowing of repair following injury, with a consequent prolongation of convalescence; a decreased tolerance for stresses of all kinds; and a decreased tolerance for some drugs. Also affecting the course of illness and its treatment are the fixed physical and mental habits of older people, which can be changed only slowly and gradually, and the emotional attitudes and difficulties which condition their lives.
The aged person is, then, more frequently attacked by illness, particularly of the chronic variety, and when he is attacked, the disease is likely to last longer and cause him more disability than it would a younger person. He has to stay in bed longer and he is more likely to suffer complications. He finds it harder to adjust to the change in living occasioned by the illness and its treatment and, finally, he is more likely to die from it.
There is a widespread misconception that if retirement were not required at age 65 we would transfer a tremendous number of____________________