Longevity In Men Research Articles

The evolution of human longevity.

THE EVOLUTION OF HUMAN LONGEVITY ROBIN HOLLIDAY* Most animals live in a hazardous natural environment. The major problems confronted are scarcity of food or water, predators, and disease. A high mortality means that few, if any, individuals reach an age where senescence becomes apparent. This was first made clear by Medawar in outlining a new theory for the evolution of ageing, and Williams independently developed a similar theory [1, 2]. Medawar proposed that deleterious mutations acting late in life would not be selected against, so could accumulate, and eventually bring about senescence. Williams emphasized the importance ofpleiotropic genes which had beneficial effects early in life but deleterious effects in late maturity. The Medawar-Williams theory has subsequently been the cornerstone ofextensive and comprehensive discussions by others [3-10]. It is universally agreed that populations are age-structured, and that there are many more young breeding adults than old ones. The life history of any given species is based on several parameters, including the time taken to reach reproductive maturity, the rate of reproduction, the mortality from birth onwards, and the lifespan. It is evident that if mortality is very high, then rapid growth to reproductive maturity and a high rate of reproduction is necessary to allow the population to survive. In these species maximum lifespan is short. In contrast, animals with low annual mortality can evolve slow rates of growth and reproduction, and a long lifespan. As well as the extensive theoretical studies, there is also experimental work with Drosophila which confirms some of the basic conclusions. Starting with a heterozygous population, offspring were selected from the oldest parents over successive generations. After many generations of selection , the time of onset of reproduction was significantly greater and there was an increase in longevity [4, 10-12]. In mammals, there are examples of the evolution of progressively shorter The author acknowledges with gratitude the helpful comments of Leslie Orgel and Linda Partridge. *CSIRO Division of Biomedical Engineering, Sydney Laboratory, North Ryde, NSW 2113 Australia.© 1996 by The University of Chicago. All rights reserved. 0031-5982/96/3903-0942$01.00 100 Robin Holliday ¦ Evolution ofHuman Longevity 15 C O fi 10 3 "D O ?a a> (L d 5 •14 •11 •12 ·13 •10 •7 •9 •8 •1 2· ·3 •4 10 20 30 40 50 Longevity (years) 60 70 80 Fig. 1.—The relationship between the age of onset of reproduction of primate genera, including the gestation period, and their maximum life span. 1, Slow loris (Nyctocebus) ; 2, Slender loris (Loris); 3, Mouse lemur (Microcebus) ; 4, Brown lemur (Lemur); 5, Squirrel monkey (Saimirí); 6, Marmoset (Calithrix); 7, Spider monkey (Atetes); 8, Macaque (Macaca); 9, Baboon (Papio); 10, Gibbon (Hylobales); 11, Chimpanzee (Pan); 12, Gorilla (Gorilla); 13, Orangutan (Pongo); 14, Human (Homo). The sources of information are [13-17] and M. L. Jones, personal communication. The estimation of maximum longevity is from small numbers of animals held in captivity. Although the maximum recorded human lifespan is 120 years, this is based on the records of a very large number of individuals. A small cohort, comparable to that of captive animals, is likely to have a life span of about 80 years. lifespan and progressively longer ones. Amongst carnivores, the stoats and weasels have evolved a life history in which survival depends on continuous availability of food, and mortality from starvation is high. Growth to reproductive maturity is rapid, and litter size is large. Lifespan even in a protected zoo environment is only a few years [13] . In contrast, the primates provide one of the best examples of the evolution of a longer lifespan. It is evident that there is a clear relationship between the age of reproductive maturity and the maximum lifespan, which is illustrated in Figure 1. Man is not only Perspectives in Biology and Medicine, 40, 1 ¦ Autumn 1996 101 the longest living primate, but the longest living mammalian species. The reasons for the evolution of increased longevity in man have not been satisfactorily explained. In this article, I discuss the life history parameters of the earliest humans and suggest how a longer lifespan evolved by natural selection. In natural environments it is common, but of course not invariable...

Exercise Intensity and Longevity in Men

To the Editor. —The article by Dr Lee and colleagues 1 on intensity of physical activity and longevity provides additional evidence that physical activity is associated with improved survival. Some points, however, may require further clarification. Different criteria were used to categorize the energy expenditure in specific analytical approaches. Quintiles were shown in Table 1 and in the total energy expenditure multivariate analysis (range, 13142 kJ/wk), eight categories were used when analyzing the age-adjusted associations with mortality (range, 14 700 kJ/wk, Table 2), and five categories were used in the multivariate models (range, 6300 kJ/wk, Tables 3 and 4). Consequently, it is impossible to match the results across the tables. This may confuse readers, and the reasons for presenting the data in such different groupings are not known. Vigorous, but not nonvigorous, physical activities were associated with longevity. From a practical point of

Exercise intensity and longevity in men

Exercise intensity and longevity in men

Exercise intensity and longevity in men. The Harvard Alumni Health Study

Exercise intensity and longevity in men. The Harvard Alumni Health Study

Exercise Intensity and Longevity in Men

To examine the independent associations of vigorous (> or = 6 resting metabolic rate [MET] score) and nonvigorous (< 6 MET score) physical activity with longevity. Prospective cohort study, following up men from 1962 or 1966 through 1988. Subjects were Harvard University alumni, without self-reported, physician-diagnosed cardiovascular disease, cancer, or chronic obstructive pulmonary disease (n = 17,321). Men with a mean age of 46 years reported their physical activities on questionnaires at baseline. All-cause mortality (3728 deaths). Total energy expenditure and energy expenditure from vigorous activities, but not energy expenditure from nonvigorous activities, related inversely to mortality. After adjustment for potential confounders, the relative risks of dying associated with increasing quintiles of total energy expenditure were 1.00 (referent), 0.94, 0.95, 0.91 and 0.91, respectively (P [trend] < .05). The relative risks of dying associated with less than 630, 630 to less than 1680, 1680 to less than 3150, 3150 to less than 6300, and 6300 or more kJ/wk expended on vigorous activities were 1.00 (referent), 0.88, 0.92, 0.87, and 0.87, respectively (P [trend] = .007). Corresponding relative risks for energy expended on nonvigorous activities were 1.00 (referent), 0.89, 1.00, 0.98, and 0.92, respectively (P [trend] = .36). Analyses of vigorous and nonvigorous activities were mutually adjusted. Among men who reported only vigorous activities (259 deaths), we observed decreasing age-standardized mortality rates with increasing activity (P = .05); among men who reported only nonvigorous activities (380 deaths), no trend was apparent (P = .99). These data demonstrate a graded inverse relationship between total physical activity and mortality. Furthermore, vigorous activities but not nonvigorous activities were associated with longevity. These findings pertain only to all-cause mortality; nonvigorous exercise has been shown to benefit other aspects of health.

Decelerated growth and longevity in men

Severe dietary restriction delays the physical development of rodents and leads to adult animals of reduced body size but significantly increased life expectancy. We tried to find a similar relationship in human populations using demographical and statistical methods. We show for the total Spanish male population that the mean adult body height reliably reflects the regional living and nutritional conditions. This relation does not only hold for todays socioeconomic data but can also be reproduced using data on family income in the mid 19th century. We calculated the mean height of young men liable to the military service around 1860 and determined their longevity retrospectively using posterior census data. This was done separately for all the Spanish provinces. The linear regression between both parameters manifests a statistically highly significant relationship: the smaller the mean height at age 18 in a province, the higher the chance for people living there to reach high chronological ages. Migrational movements, selection, mortality due to epidemics or unreliability of the population censuses can be largely ruled out as explications for the described correlation. Furthermore, we determined the secular growth trend in Spain for the last 130 years. From 1860 to 1920 the mean height increased by 2.7 cm, from 1920 to 1987 by another 9.8 cm. Since 1950 the trend is above 2 cm per decade country-wide. From 1974 onwards it amounts to 2.89±0.17 cm per decade. Such high values were worldwide looked upon as isolated cases found only in geographically and socially isolated population subgroups during very limited periods.

Longevity of man: relative weight and fatness in middle age.

By February, 1948, examinations in the Twin Cities Prospective Study were completed on 284 executive men, then aged 45-55 and "healthy". In 35 years 183 died, 110 were alive, one was lost. Entry body fatness, indicated by body mass index, skinfold thickness at three sites, relative girth, and body density, did not significantly discriminate the 35-year dead from survivors. Age at death was not related to any fatness measure. The multiple logistic equation in five solutions using age, blood pressure and smoking plus each fatness item separately, found no discrimination of dead from survivors by any fatness measure. In other long time prospective studies, two suggested excess mortality at far extremes of over- and under-weight, several found survivors significantly fatter than the dead, others found no relation between fatness and longevity. Framingham reported fatness a risk factor for death when allowance is made for smoking but that singular claim has been criticized.

Smoking, mortality, and six in a community hospital necropsy population.

Analysis of 344 necropsies at a community hospital disclosed a male to female ratio of 1.9:10 and a smoking incidence over twice that of the general population. Overall longevity for men was less than for women. Intragroup comparisons showed an inverse relationship between smoking and longevity. Smokers in general and subsets of male and female smokers thus died earlier than respective nonsmokers. Trends for nonsmoking men and women were not different. However, smoking women surprisingly died earlier than smoking men at comparable pack-year exposure levels. Conversely, nonsmokers were most likely to achieve old age with freedom from diseases usually associated with smoking. We conclude that smoking predisposes to hospitalization, with premature death. Men suffer the most, probably because of traditionally heavier usage. For reasons unclear, however, women who do smoke may exhibit excessive vulnerability in some situations.

Mitral valve replacement in elderly patients: Encouraging postoperative clinical and hemodynamic results

Increasing longevity in man will make cardiac surgery more common in elderly patients. This report compares the results of isolated mitral valve replacement (MVR) in older and in younger patients. Forty-three patients aged 60 years and older (average. 65) were compared to 167 patients under 60 years of age (average, 46), all of whom underwent isolated MVR for similar operative indications. Eighty-one percent of both groups returned for catheterization 5 to 8 months after operation. Hospital mortality rate was 10 percent in younger patients and 14 percent in the older patients. Long-term follow-up averaged 60 months in the younger group and 54 months in the older patients. Both populations were divided into patients with pure or predominant mitral stenosis (MS) or pure or predominant mitral regurgitation (MR). There was no statistically significant difference (p > 0.05) in the preoperative and postoperative values of pulmonary artery pressure, left atrial pressure, left ventricular end-diastolic pressure, mitral valve mean gradient, or cardiac index in the younger vs. the older patients in either the MS or the MR subgroup. There was no significant difference in symptomatic improvement in the younger vs. older patients with MS. However, the younger patients with MR improved by 1.2 functional classes while the older patients improved by 2.0 classes. It is concluded that MVR is associated with the same low risk and brings about a similar hemodynamic improvement in left ventricular pump function in patients older and younger than 60 years.

Evolution of human longevity: A critical overview

Evolution of longevity of the ungulates, carnivores and primates is reviewed. Special emphasis is focused on recent evolutionary history of longevity along the hominid ancestral-descendant sequence leading to modern man. Maximum life span potential (MLP) or the change in MLP is predicted in extinct species by (1) a phylogenetic analysis of the MLP of present living species and (2) an empirical equation using brain and body weight estimates from fossils. Both of these methods indicate MLP generally increased during mammalian evolution and at an extremely fast rate during the appearance of the hominid species. These results suggest that relatively few genetic alterations were necessary during the recent evolutionary history of man to significantly extend his innate ability to maintain mental and physical health. Much evidence indicates these genetic alterations principally involve regulatory genes, which control a conserved set of structural genes. Evolution of longevity in man could therefore be a result of simple changes in temporal and quantitative gene expression. Whether these genetic alterations result from mutational changes and/or chromosomal rearrangement cannot yet be evaluated.

Pathologic correlation of gallstones: a review of 1,847 autopsies of patients with gallstones.

Introduction Cholelithiasis has been described as a disease of With the improvement in the longevity of man, an increasing incidence of gallstones and complications thereof is to be anticipated; i. e., parenthetically, then, one should add that cholelithiasis is a disease of an civilization. Although a large bibliography exists identifying surveys of clinical cases relating to etiological factors for gallstones, remarkably few autopsy reports purport to do the same thing. In many respects, necropsy studies alone could contribute such information. The existence of pathologic conditions of related and unrelated organs are often not recognizable by clinical or laboratory methods alone. In an aging population, it becomes increasingly important to know what coexistent or complicating disease the physician must be prepared to meet. It was felt, then, that the data from a large autopsy material such as ours would fill a few of the gaps in our knowledge. Material

Causes of longevity in man

Drug Prescribing for Patients with Chronic Kidney Disease in General Practice: a Cross-Sectional Study

Research in Aging: Its Scope and Objectives

Any consideration of the vast research in aging which in its entirety constitutes the field of Gerontology must recognize that it depends primarily on the evaluation of accumulated data based on experiences in the field and in the laboratory of many differently trained investigators. The research of necessity involves observations in biology, psychology and sociology in their broadest implication with their respective manifold ramifications. The science of aging and the study of the aged, Gerontology, has been with us in some form or other as a matter of record as early as the 15th century. Ponce de Leon's quest for the Fountain of Youth is but one of the historical milestones marking man's desire to live longer-younger. However, this specialized field of study, the Science of Gerontology, as we now know it, is in itself a young science. The Journal of Gerontology, the official publication of the Gerontological Society Incorporated, is in its eleventh (11th) volume, only in its early teens, not even mature as measured in the life-span of man. A span which has almost doubled in the last fifty years. According to the latest reports (Dublin) the twenty year old living in 1975 can look forward to living 54 additional years. A gain of four years over the current expectancy of 70 years as reported in the Statistical Bulletin of the Metropolitan Life Insurance Company. What are the factors concerned in this longevity of man? What has been done to bring it about? What is being done to maintain it? What can be done to improve it? And most important, what should be done to create the best atmosphere for this aging society? Public attention is now focused on the increasing number of older people in our population with the result that government, industry, education as represented by Colleges, Universities, and Research Foundations, have instituted Committees, Symposia, courses of study and councils on aging. All of this is with the objective of understanding the myriad factors concerned with the complex picture of how our older citizens are best to maintain their bodily health, their mental vigor and longer continue to be useful and remain as an asset to the community. We are being assured that within our society are the basic ingredients to create a more wholesome atmosphere for older people (Kutner et al). Professional activities have become sharply focused on this problem. The biologist is more concerned now with analyzing the nature of aged cells, organs, organ systems, as well as changes in metabolism,

Diet and Disease

The natural longevity of man is directly influenced by several factors and among the more important of these may be mentioned inheritance, environment, occupation and nutrition. Man has succeeded in his “struggle for existence” because of the development of agents of defense, external and internal. By means of his intelligence, he has been able to devise methods of defense and offense against external enemies. As the gift of his inheritance, he has developed internal defensive agents which are shared by the whole animal kingdom. These are many and elusive, exist in his tissues, and are both cellular and humoral in character. By their means, individually and racially, he has waged a defensive and offensive battle against infectious diseases; many individuals succumbing, Homo sapiens, as a species, surviving. To this end, environment, hygienic and climatic, is a contributing factor, as well as occupation, many forms of which predispose to disease.

Noting the “Imperceptible” — Proposed Homeopathic Sanatoria for Consumptives — Report of the Rhode Island Tuberculosis Commission — A New Bacteriologic Museum — Potential Longevity in Man and Other Animals — Insanity in London — Medical Notes

Noting the “Imperceptible” — Proposed Homeopathic Sanatoria for Consumptives — Report of the Rhode Island Tuberculosis Commission — A New Bacteriologic Museum — Potential Longevity in Man and Other Animals — Insanity in London — Medical Notes

Inheritance of Longevity in Man

THE object of this paper2 is twofold, namely:— (1) To ascertain whether duration of life is inherited, and (2) To exhibit natural selection at work in man. According to both Wallace and Weismann the duration of life in any organism is determined by natural selection. An organism lives so long as it is advantageous, not to itself, but to its species that it should live. But it would be impossible for natural selection to determine the fit duration of life, as it would be impossible for it to fix any other character, unless that character were inherited. Accordingly a preliminary inquiry as to whether duration of life is inherited or not seems needful before we consider further the plausibility of Wallace and Weismann's hypothesis. The present paper shows that directly and collaterally duration of life is certainly inherited in the male line. We believe this to be the first quantitative measure of the inheritance of life's duration. Further data for the inheritance of this character in the female line, and for the study of the inheritance of “brachybioty”or shortlivedness as distinguished from longevity are now being collected. We point out in the paper and endeavour to illustrate by examples the importance of such quantitative measure of the inheritance of life's duration for actuarial practice.

Consciousness and Volition

IN an interesting review of Lankester's “Comparative Longevity in Man and the Lower Animals,” which recently appeared in the Times, is the following sentence:—“Once commenced, its continuance (that of the act of walking) is quite involuntary, and may even be unnoticed by the consciousness.” I am anxious to ascertain, from those readers of NATURE who have paid special attention to psychology, whether this is, in their opinion, a correct statement of the condition of the mind during such an habitual act as that of walking. There are undoubtedly certain actions of the body, those denominated reflex, which are performed without any exercise of the will whatever; but these are all either momentary, or, if continued, are nearly uniform and unchanging. To me it seems impossible that any action which is constantly varying can be wholly involuntary. Take, for instance, the motion of the fingers in writing: we are absolutely unconscious of the exercise of the mental faculties by which each successive change in the position of the pen is regulated; but yet is it not certain that each up-stroke and down-stroke is the consequence of a separate effort of the will? There is here an evident connection between the state of mind at the time and the action of the body; and by what other means is it possible to suppose that the mental act which conceives the word we are writing can convey its instruction to the fingers? Certainly not by any process of instinct. A better instance perhaps is in the motion of the muscles of the face and throat in speaking. These muscles are entirely under the control of the will; and every separate motion of them must surely be effected by a distinct voluntary effort, of which however we are entirely unconscious. The same seems to me the case in walking. When we sway the body out of the perpendicular in turning a corner, I am at a loss to understand how this can be performed involuntarily. The explanation seems to me to be that consciousness cannot, so to speak, work so fast as volition, and therefore cannot take cognizance of a large number of rapidly successive acts of the will. The question is not so much one of a nice metaphysical distinction as simply of a correct use of terms, although I am afraid I am opposing the views of such high authorities as Huxley and Carpenter. We have been made familiar with the term Unconscious Cerebration. Is there not also an enormous field of Unconscious Volition?

On Comparative Longevity in Man and the Lower Animals

IN this interesting little essay Mr. Lankester appears to have accumulated most of the facts with which we are at present acquainted, in respect to the duration of life. He defines longevity to be the length of time during which life is exhibited in an individual; but does not, of course, apply the term individual to entire masses proceeding, as in the case of alsinastrum and many polypes, from a process of asexual generation; and he proceeds to point out that there is a longevity belonging to the species, and a longevity characteristic of the individual, and further, that the average longevity of a species never equals its potential longevity, since a thousand accidents happen to destroy individuals at an early period of their lives; he then distinguishes between normal and absolute potential activity, and shows that in man alone do these two nearly coincide. On Comparative Longevity in Man and the Lower Animals. By E. Ray Lankester, B.A., Junior Student of Christ Church, Oxford. (London: Macmillan and Co. 1870.)

On Comparative Longevity in Man and the Lower Animals

On Comparative Longevity in Man and the Lower Animals