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Some Reflections on Senility and Nutrition from the Clinical Standpoint
SOME REFLECTIONS ON SENILITY AND NUTRITION FROM THE CLINICAL STANDPOINT TRUMAN
G.
SCHNABEL,
M.D., F.A.C.P. *
The Shift in Age Distribution of Our Population.-With an ever lengthening life's expectancy in this country and with an ever increasing proportion of elderly people in our population, an increasing amount of attention is being focused on the processes of senescence and senility. Two new journals, one of Gerontology and the other of Geriatrics, have recently started publication, the U. S. Public Health Service has established a division of Gerontology in the National Institute of Health, much research is going on in the hope that important old age problems may be answered thereby and many communities are concerning themselves with matters related to the better housing and care of their aged citizens. The shift in the distribution of both our white and black population from youth to middle and old age has taken place largely because of increasingly effective facilities for the prevention and cure of infections and infectious diseases in infants, middle aged people, and the elderly. It must be only in minor degree that the shift in the age distribution of our population has been influenced by the use of insulin in diabetes, by the availability of more elaborate and better surgical technics in older people and probably by the application of better hygienic principles for people generally in this country. All the while not too much has been learned which has enhanced our understanding of arteriosclerosis, arterial hypertension, osteoarthrosis and cancer, all progressive diseases characteristic of senescence. At least very little has evolved from extensive research in these fields as well as in matters relating to the experience of aging which has served to change the age pattern of our population. Complexity of Disease in the Aged.-With reference to the above socalled degenerative diseases including diabetes, it is unfortunately common practice to regard the elderly patient as being ill of only one of them, usually that one whose symptom picture presents itself most prominently. As a matter of fact, he or she ordinarily presents good evidence pointing to the presence of more than one and often all of these diseases, to say nothing of an added acute illness. In addition to this superimposition and overlapping of disease entities in old people, one must· remember that their diseases are born of many causes, that different etiological factors prevail, and that their disease picture will vary from patient to patient. Senescence then, with all of its potential disease possibilities, whether degenerative or not, is more complicated and conFrom the Medical Division, Philadelphia General Hospital. * Professor of Medicine, University of Pennsylvania School of Medicine; Visiting Physician, Philadelphia General Hospital. 1681
1682
TRUMAN G. SCHNABEL
trasts sharply with childhood and adolescence in this respect. In the latter age periods diseases are usually exogenous, more obvious, single, and of recent origin; the onset and course tend to be acute or subacute and there is little variation from patient to patient. Poor Cellular Nutrition a Factor.-Although the diseases of old age are complex when considered from any standpoint, all sooner or later exhibit the effects of poor cellular nutrition. Parenchymal cells are especially sensitive to the status of their milieu. They are dependent for nutrition upon the substance of an intercellular matrix and any change here may make for disordered function and structural change. For the full maintenance of good cellular function and structural integrity, it would seem highly important that food intake must be adequate quantitatively and qualitatively in every way. The products of digestion must be effectively and efficiently distributed by the cardiovascular, lymphatic and blood systems and they must be utilized when so distributed. Besides all of this, injurious metabolic products must not accumulate and thereby impair cellular activity. So it would seem that, in its broadest sense, nutrition should be maintained at an optimal level if one is interested in the prevention of the degenerative diseases of old age, to say nothing of the prolongation of life, or if one must act when these diseases have taken on their irreversible roles. Optimal Diets.-The optimal level of nutrition for anyone individual and particularly one who is aging is, unfortunately, a matter of uncertainty. Leonard A. Maynard, director of the School of Nutrition, Cornell University, is responsible for the following: "Our understanding of nutritional requirements during the last half of life is much less than for the period of growth because we know less about tissue changes which are taking place. A child falls down, jumps up and goes blithely on its way. An old man falls down and breaks his hip. What difference in physiochemical structure of bone is invoked? We understand the role of nutrition in building bone during growth but little about its possible contribution in retarding changes." Maynard and his collaborator McCay found in the course of a ten year study of adult nutrition that, on comparing the performance of a group of rats growing at a normal rate with a group made to grow slowly by restricting the caloric intake, those on the restricted diet lived longer and preserved some of their youthful characteristics longer. These conclusions were so generally contrary to prevalent conceptions of nutrition that these men began a long-term study of the relation of nutrition to the physiology and pathology of middle age and old age. Completing the preliminary phase of their program in 1941, they began a second project planned to run from ten to twenty years, to clarify such concrete points as the following: the effect of the amount of water consumed on the life span; the relationship of body fatness and exercise to longevity; the effect of common salt and calcium phosphate upon aging; the optimum adult consumption of vitamins; the relationship of exercise at different periods of life to the development of senility and the psychology in aging rats.
SENILITY AND NUTRITION
1683
While the laboratory has been slow in unfolding the riddle of old age and its diseases, clinical observation and study have done no better in this regard. A long-time experience with aged people in the Philadelphia General Hospital has not revealed the sort of a diet and practices which will guarantee for long life and the prevention of degenerative diseases. For the most part, however, the aged persons in our institution are not overweight, and certainly not obese, which is to be expected. Obesity shortens longevity chiefly because it calls for a metabolic rate far in excess of that required by ideally weighted individuals of the same age and sex. Some of the elderly population of our institution have always been thin according to reliable testimony and at the same time are reported to have been "good eaters" with no peculiar dietary habits. Others have obviously reached their old age in spite of eating food predominantly of one variety, usually carbohydrates, all of which may seem out of line with what is regarded as being healthful. Others have obviously lost weight prior to their hospital admissions because of a food intake of caloric inadequacy. Under such circumstances it frequently is difficult to decide whether the patient's disease has been responsible for anorexia or whether somehow or other appetite is paced to the ever decreasing energy requirements of old age, this being in effect an example of adaptation. A goodly portion of the aged who have gradually lost weight have evidently been influenced in their dietary habits by disturbances of the psyche related usually to degenerative changes in the cerebrovascular supply. Very few of our patients seem to have lost weight because of a background of poverty. So it would seem that aged patients arrive at a time in their lives when they require admission to a general hospital with various dietary histories in their pasts, and judging by the criterion of weight loss mayor may not be in a good state of nutrition. With the return of appetite as the disease state tends to improve some of the elderly patients will regain lost weight during a hospital stay-sufficient evidence that for a time before admission the patient was subsisting on an inadequate diet. On discharge from the hospital such as these seem to look better and seem to be younger. Vitamin Supplements.-Outright evidence of vitamin deficiency is not a prominent feature in the aged as we have observed them here in the hospital. Occasionally conjunctival xerosis and follicular keratoses are found. Sometimes these old people may exhibit fissuring at the angles of the lips, a degree of lingual atrophy or magenta coloring. Frank pellagrous lesions, nutritional edema, or polyneuritis are seldom noted in the old patients, but are usually seen in those who have also been alcoholics. Even though frank evidences of vitamin deficiencies are rarely found, we have thought it well to bear in mind that the aged probably plod along at a suboptimal vitamin level. We feel, therefore, that a supplementary intake of vitamins is probably needed by the aged because they may require more vitamin Bl if they are on a high carbohydrate diet, of if they fail to absorb, inadequately utilize, or overdestroy and 6
1684
TRUMAN G. SCHNABEL
eliminate vitamins. These same possibilities apply equally well to proteins, fats, carbohydrates, calcium, phosphorous, and minerals generally. The Difficulty of Distinguishing between Normal and Abnormal.Clinically it is somewhat perplexing to know whether or not certain features which present themselves in our aged person should be counted as normal or abnormal. For example, when is one to look upon a delayed sugar tolerance curve which one may discover in an aged person as evidence of real diabetes or even count it as potential diabetes, and when should one act thereon therapeutically. Obviously diabetes while being a disease of metabolism carries with it consequences of a disordered state of nutrition. In the absence of normal criteria in this regard, it has seemed better to treat patients exhibiting any quantitative deficiency in carbohydrate metabolism as diabetics. Until definite normals are established for senility it seems likewise better to regard evidences of renal dysfunction as signs of renal disease, electrocardiographic deviations from the younger adult normals as evidence of real heart disease, and any degree of anemia as abnormal and calling for an appropriate degree of treatment. Hopeful Aspects of Dietotherapy in Vascular Sclerosis.-0ur old patients, as do those of all doctors, give one an impression that arteriosclerosis is part of the aging process because almost all of them present in some degree the presence of some type of vascular sclerosis. Some of our patients of a well advanced age have degenerative vascular changes in a minor degree and such changes are similar to those observed in younger patients without any signs of senescence. The histories of our arteriosclerotic patients strongly point to a congenital background for their disease but other considerations would seem to place such patients in a metabolic order of an acquired type. This makes the arteriosclerotic picture a more hopeful one from the preventive standpoint. Lesions of arteriosclerosis are irreversible in spite of claims made by those who practice sympathectomies or prescribe rice-fruit diets for hypertension. It may then finally develop that diet and a way of life will serve, if not to prevent these vascular changes, at least to slow up the rate of their development. A way of correcting faulty lipid metabolism may some day be discovered or a means of counteracting unusual hormonal activity may be evolved, or some new unknown etiological factor may be unearthed. In any event there will always be the matter of nutrition to consider in its broadest implications. When surveys will have been made of the life and dietary habits of a large portion of the population over a long period of time, and when laboratory research will have mastered the problems of nutrition in the aged, then the limits of life's expectancy will be increased by many, many more years.
G.
SCHNABEL,
M.D., F.A.C.P. *
The Shift in Age Distribution of Our Population.-With an ever lengthening life's expectancy in this country and with an ever increasing proportion of elderly people in our population, an increasing amount of attention is being focused on the processes of senescence and senility. Two new journals, one of Gerontology and the other of Geriatrics, have recently started publication, the U. S. Public Health Service has established a division of Gerontology in the National Institute of Health, much research is going on in the hope that important old age problems may be answered thereby and many communities are concerning themselves with matters related to the better housing and care of their aged citizens. The shift in the distribution of both our white and black population from youth to middle and old age has taken place largely because of increasingly effective facilities for the prevention and cure of infections and infectious diseases in infants, middle aged people, and the elderly. It must be only in minor degree that the shift in the age distribution of our population has been influenced by the use of insulin in diabetes, by the availability of more elaborate and better surgical technics in older people and probably by the application of better hygienic principles for people generally in this country. All the while not too much has been learned which has enhanced our understanding of arteriosclerosis, arterial hypertension, osteoarthrosis and cancer, all progressive diseases characteristic of senescence. At least very little has evolved from extensive research in these fields as well as in matters relating to the experience of aging which has served to change the age pattern of our population. Complexity of Disease in the Aged.-With reference to the above socalled degenerative diseases including diabetes, it is unfortunately common practice to regard the elderly patient as being ill of only one of them, usually that one whose symptom picture presents itself most prominently. As a matter of fact, he or she ordinarily presents good evidence pointing to the presence of more than one and often all of these diseases, to say nothing of an added acute illness. In addition to this superimposition and overlapping of disease entities in old people, one must· remember that their diseases are born of many causes, that different etiological factors prevail, and that their disease picture will vary from patient to patient. Senescence then, with all of its potential disease possibilities, whether degenerative or not, is more complicated and conFrom the Medical Division, Philadelphia General Hospital. * Professor of Medicine, University of Pennsylvania School of Medicine; Visiting Physician, Philadelphia General Hospital. 1681
1682
TRUMAN G. SCHNABEL
trasts sharply with childhood and adolescence in this respect. In the latter age periods diseases are usually exogenous, more obvious, single, and of recent origin; the onset and course tend to be acute or subacute and there is little variation from patient to patient. Poor Cellular Nutrition a Factor.-Although the diseases of old age are complex when considered from any standpoint, all sooner or later exhibit the effects of poor cellular nutrition. Parenchymal cells are especially sensitive to the status of their milieu. They are dependent for nutrition upon the substance of an intercellular matrix and any change here may make for disordered function and structural change. For the full maintenance of good cellular function and structural integrity, it would seem highly important that food intake must be adequate quantitatively and qualitatively in every way. The products of digestion must be effectively and efficiently distributed by the cardiovascular, lymphatic and blood systems and they must be utilized when so distributed. Besides all of this, injurious metabolic products must not accumulate and thereby impair cellular activity. So it would seem that, in its broadest sense, nutrition should be maintained at an optimal level if one is interested in the prevention of the degenerative diseases of old age, to say nothing of the prolongation of life, or if one must act when these diseases have taken on their irreversible roles. Optimal Diets.-The optimal level of nutrition for anyone individual and particularly one who is aging is, unfortunately, a matter of uncertainty. Leonard A. Maynard, director of the School of Nutrition, Cornell University, is responsible for the following: "Our understanding of nutritional requirements during the last half of life is much less than for the period of growth because we know less about tissue changes which are taking place. A child falls down, jumps up and goes blithely on its way. An old man falls down and breaks his hip. What difference in physiochemical structure of bone is invoked? We understand the role of nutrition in building bone during growth but little about its possible contribution in retarding changes." Maynard and his collaborator McCay found in the course of a ten year study of adult nutrition that, on comparing the performance of a group of rats growing at a normal rate with a group made to grow slowly by restricting the caloric intake, those on the restricted diet lived longer and preserved some of their youthful characteristics longer. These conclusions were so generally contrary to prevalent conceptions of nutrition that these men began a long-term study of the relation of nutrition to the physiology and pathology of middle age and old age. Completing the preliminary phase of their program in 1941, they began a second project planned to run from ten to twenty years, to clarify such concrete points as the following: the effect of the amount of water consumed on the life span; the relationship of body fatness and exercise to longevity; the effect of common salt and calcium phosphate upon aging; the optimum adult consumption of vitamins; the relationship of exercise at different periods of life to the development of senility and the psychology in aging rats.
SENILITY AND NUTRITION
1683
While the laboratory has been slow in unfolding the riddle of old age and its diseases, clinical observation and study have done no better in this regard. A long-time experience with aged people in the Philadelphia General Hospital has not revealed the sort of a diet and practices which will guarantee for long life and the prevention of degenerative diseases. For the most part, however, the aged persons in our institution are not overweight, and certainly not obese, which is to be expected. Obesity shortens longevity chiefly because it calls for a metabolic rate far in excess of that required by ideally weighted individuals of the same age and sex. Some of the elderly population of our institution have always been thin according to reliable testimony and at the same time are reported to have been "good eaters" with no peculiar dietary habits. Others have obviously reached their old age in spite of eating food predominantly of one variety, usually carbohydrates, all of which may seem out of line with what is regarded as being healthful. Others have obviously lost weight prior to their hospital admissions because of a food intake of caloric inadequacy. Under such circumstances it frequently is difficult to decide whether the patient's disease has been responsible for anorexia or whether somehow or other appetite is paced to the ever decreasing energy requirements of old age, this being in effect an example of adaptation. A goodly portion of the aged who have gradually lost weight have evidently been influenced in their dietary habits by disturbances of the psyche related usually to degenerative changes in the cerebrovascular supply. Very few of our patients seem to have lost weight because of a background of poverty. So it would seem that aged patients arrive at a time in their lives when they require admission to a general hospital with various dietary histories in their pasts, and judging by the criterion of weight loss mayor may not be in a good state of nutrition. With the return of appetite as the disease state tends to improve some of the elderly patients will regain lost weight during a hospital stay-sufficient evidence that for a time before admission the patient was subsisting on an inadequate diet. On discharge from the hospital such as these seem to look better and seem to be younger. Vitamin Supplements.-Outright evidence of vitamin deficiency is not a prominent feature in the aged as we have observed them here in the hospital. Occasionally conjunctival xerosis and follicular keratoses are found. Sometimes these old people may exhibit fissuring at the angles of the lips, a degree of lingual atrophy or magenta coloring. Frank pellagrous lesions, nutritional edema, or polyneuritis are seldom noted in the old patients, but are usually seen in those who have also been alcoholics. Even though frank evidences of vitamin deficiencies are rarely found, we have thought it well to bear in mind that the aged probably plod along at a suboptimal vitamin level. We feel, therefore, that a supplementary intake of vitamins is probably needed by the aged because they may require more vitamin Bl if they are on a high carbohydrate diet, of if they fail to absorb, inadequately utilize, or overdestroy and 6
1684
TRUMAN G. SCHNABEL
eliminate vitamins. These same possibilities apply equally well to proteins, fats, carbohydrates, calcium, phosphorous, and minerals generally. The Difficulty of Distinguishing between Normal and Abnormal.Clinically it is somewhat perplexing to know whether or not certain features which present themselves in our aged person should be counted as normal or abnormal. For example, when is one to look upon a delayed sugar tolerance curve which one may discover in an aged person as evidence of real diabetes or even count it as potential diabetes, and when should one act thereon therapeutically. Obviously diabetes while being a disease of metabolism carries with it consequences of a disordered state of nutrition. In the absence of normal criteria in this regard, it has seemed better to treat patients exhibiting any quantitative deficiency in carbohydrate metabolism as diabetics. Until definite normals are established for senility it seems likewise better to regard evidences of renal dysfunction as signs of renal disease, electrocardiographic deviations from the younger adult normals as evidence of real heart disease, and any degree of anemia as abnormal and calling for an appropriate degree of treatment. Hopeful Aspects of Dietotherapy in Vascular Sclerosis.-0ur old patients, as do those of all doctors, give one an impression that arteriosclerosis is part of the aging process because almost all of them present in some degree the presence of some type of vascular sclerosis. Some of our patients of a well advanced age have degenerative vascular changes in a minor degree and such changes are similar to those observed in younger patients without any signs of senescence. The histories of our arteriosclerotic patients strongly point to a congenital background for their disease but other considerations would seem to place such patients in a metabolic order of an acquired type. This makes the arteriosclerotic picture a more hopeful one from the preventive standpoint. Lesions of arteriosclerosis are irreversible in spite of claims made by those who practice sympathectomies or prescribe rice-fruit diets for hypertension. It may then finally develop that diet and a way of life will serve, if not to prevent these vascular changes, at least to slow up the rate of their development. A way of correcting faulty lipid metabolism may some day be discovered or a means of counteracting unusual hormonal activity may be evolved, or some new unknown etiological factor may be unearthed. In any event there will always be the matter of nutrition to consider in its broadest implications. When surveys will have been made of the life and dietary habits of a large portion of the population over a long period of time, and when laboratory research will have mastered the problems of nutrition in the aged, then the limits of life's expectancy will be increased by many, many more years.