There can be no sharp line of division between health and disease if we consider disease a depreciation of health. Health is always relative. But we must remember that disease does not necessarily imply disaster. There is not an individual in this room who is free of disease in the sense of having some depreciation of health. I have two chronic, utterly incurable diseases-one an arthritis of the hip that makes me wax profane at times and that kept me out of the Army, and the other an absolutely incurable optimism. I am perfectly willing to admit these disorders for they are not unique. It were better if all of us were aware of our defects in health and modified our lives accordingly. The adult who brags about his "perfect health" is suffering hazardous delusions. As health is always relative, there is always room for improvement.
Before leaving the subject of the biology of senescence, I should like to make one more comment regarding the theories of what aging is. As elsewhere in science, there are two opposing theories. . . . The two schools of thought regarding the basic reasons for the depreciations of aging are: (1) we wear out and (2) we rust out. One assumes that age change results from misuse or use; the other, from disuse or lack of use. The actual evidence for these two opposing concepts is so nearly equal that we may say the choice between one idea or the other depends upon the personality of the chooser. The energetic and ambitious man who bounds out of bed in the morning with vigor and enthusiasm and yodels in the cold shower says, "To age is to rust out. If I keep going, I'll go farther." The indolent, easy-going, lazy sort of chap says, "To age is to wear out. If I take it easy, I'll last longer." The actual data are just about equal. It should be kept in mind, however, that disuse, or lack of use, should be considered a form of abuse or misuse. Thus, the two theories are not truly incompatible nor mutually exclusive. Both may be correct.
But how does this theory and basic science affect you and me as individuals? To my mind, geriatric medicine is by no means limited to the senile, the aged, the decrepit, and the infirm. If it were, I would have no particular interest in geriatric medicine. The senile are the end results of senescence. What is particularly interesting is how we become senile. This morning an attempt was made at defining just when the problems of the aged begin. In many respects, the most critical phase of aging occurs in the two decades from forty to sixty. It is in this period of senescence that the changes which will ultimately disable begin and when we can hope to accomplish something by preventive measures. At that time, we have the alternative of trying to prevent unnecessary depreciation or of attempting to patch up a wreck and a ruin later on. Furthermore, there are far more aging people than there are those already old. . . .
The changes that occur with aging start far earlier than their detectable manifestations. They are silent and insidious. The superficial things, like graying hair and wrinkles, are not important. Really, what difference does it make whether the dome be covered with thatch or it be gilded? What goes on underneath is what counts, is it not? The physical implications of normal aging of personal importance are several.
First and foremost is the fact that repair after injury is slowed. We may say that for each five years we have lived it takes us an extra day to repair after a given injury, such as a sore throat or a broken leg. Little Willie, who is five years old, having suffered a sore throat, has a normal temperature after one day. . . .
Physicians sometimes find it difficult to persuade an older patient to take adequate time to convalesce, because grandpa feels that the office, or the university, will collapse and go to pieces if he does not get back promptly. It is important for the maintenance of his ego that he feel indispensable. Therefore, it is often necessary to compromise and accept six days for convalescence, one day for each ten years that grandpa has lived, instead of the more appropriate twelve days.
Second, the lessened reactions to injury and inconspicuousness of symptoms. In consequence of this relative silence, illness is often neglected too long. Delay in diagnosis and in institution of treatment is a definite and serious handicap in the practice of geriatric medicine. Depreciations in health must be searched for by thorough medical study if they are to be discovered early enough to permit of fully effective therapy.
Third, there are lessened reserves for stresses which become apparent with aging. Tolerance for heat and cold, overeating and starvation, dehydration, and salt depletion is reduced. We must learn to use our heads rather than our brawn for defense. . . .