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Concept: Longevity

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Driven by technological progress, human life expectancy has increased greatly since the nineteenth century. Demographic evidence has revealed an ongoing reduction in old-age mortality and a rise of the maximum age at death, which may gradually extend human longevity. Together with observations that lifespan in various animal species is flexible and can be increased by genetic or pharmaceutical intervention, these results have led to suggestions that longevity may not be subject to strict, species-specific genetic constraints. Here, by analysing global demographic data, we show that improvements in survival with age tend to decline after age 100, and that the age at death of the world’s oldest person has not increased since the 1990s. Our results strongly suggest that the maximum lifespan of humans is fixed and subject to natural constraints.

Concepts: Senescence, Mortality rate, Demography, Gerontology, Life expectancy, Aging, Maximum life span, Longevity

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Geographic disparities in life expectancy are substantial and not fully explained by differences in race and socioeconomic status. To develop policies that address these inequalities, it is essential to identify other factors that account for this variation. In this study we investigated whether population well-being-a comprehensive measure of physical, mental, and social health-helps explain geographic variation in life expectancy. At the county level, we found that for every 1-standard-deviation (4.2-point) increase in the well-being score, life expectancy was 1.9 years higher for females and 2.6 years higher for males. Life expectancy and well-being remained positively associated, even after race, poverty, and education were controlled for. In addition, well-being partially mediated the established associations of race, poverty, and education with life expectancy. These findings highlight well-being as an important metric of a population’s health and longevity and as a promising focus for intervention.

Concepts: Demography, Population, Life expectancy, World population, Maximum life span, Socioeconomics, Human Development Index, Longevity

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The New England Centenarian Study (NECS) was founded in 1994 as a longitudinal study of centenarians to determine if centenarians could be a model of healthy human aging. Over time, the NECS along with other centenarian studies have demonstrated that the majority of centenarians markedly delay high mortality risk-associated diseases toward the ends of their lives, but many centenarians have a history of enduring more chronic age-related diseases for many years, women more so than men. However, the majority of centenarians seem to deal with these chronic diseases more effectively, not experiencing disability until well into their nineties. Unlike most centenarians who are less than 101 years old, people who live to the most extreme ages, e.g., 107+ years, are generally living proof of the compression of morbidity hypothesis. That is, they compress morbidity and disability to the very ends of their lives. Various studies have also demonstrated a strong familial component to extreme longevity and now evidence particularly from the NECS is revealing an increasingly important genetic component to survival to older and older ages beyond 100 years. It appears to us that this genetic component consists of many genetic modifiers each with modest effects, but as a group they can have a strong influence.

Concepts: Medicine, Epidemiology, Genetic disorder, Aging, Wine, Longevity, New England Centenarian Study, Centenarian

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In the second half of the 20th century, the advances in human longevity observed have been accompanied by an increase in the disparities between countries and regions. Education is one of the strongest predictors of life expectancy. Studies have shown that both relative and absolute mortality differences by education within countries have been increasing, even in the most developed and egalitarian countries. It is possible to assume that groups of highly educated people who systematically display life expectancy levels which are higher than the observed best practice (record) life expectancy at the national level are vanguards who are leading the way toward a lengthening of life for the remaining population groups. This evidence based on population-level statistics and exploring an important single factor could inspire further discussion about the possibilities for extending human length of life at the national level. However, more comprehensive and reliable data covering a larger number of countries and more covariates are needed for understanding health effects of education and prospects of human longevity.

Concepts: Mortality rate, Demography, Population, Life expectancy, 20th century, World population, Maximum life span, Longevity

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Over the last fifty years, the number of centenarians has dramatically increased. The centenarian rate (CR) is representative of the general longevity prevalent in a nation; it indicates the number of individuals aged 100 years or above at a given date divided by the size of the corresponding cohort of a given age. Two important attributes of the CR (50-54) are that it reflects both unchanged age-specific fertility and the absence of migration in populations. It can generally be used in longevity-based evaluations of the broader concept of successful ageing. As such, this retrospective analysis of the social factors that contribute to the CR (50-54) may help to identify the factors associated with successful ageing.This study estimates the CR (50-54) and elucidates the influence of social factors on successful ageing and the CR (50-54), examining 32 member countries of the Organization for Economic Co-operation and Development (OECD).

Concepts: Age, Demography, Population, Gerontology, Ageing, Organisation for Economic Co-operation and Development, Longevity

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The search for the genetic determinants of extreme human longevity has been challenged by the phenotype’s rarity and its nonspecific definition by investigators. To address these issues, we established a consortium of four studies of extreme longevity that contributed 2,070 individuals who survived to the oldest one percentile of survival for the 1900 U.S. birth year cohort. We conducted various analyses to discover longevity-associated variants (LAV) and characterized those LAVs that differentiate survival to extreme age at death (eSAVs) from those LAVs that become more frequent in centenarians because of mortality selection (eg, survival to younger years). The analyses identified new rare variants in chromosomes 4 and 7 associated with extreme survival and with reduced risk for cardiovascular disease and Alzheimer’s disease. The results confirm the importance of studying truly rare survival to discover those combinations of common and rare variants associated with extreme longevity and longer health span.

Concepts: Gene, Epidemiology, Disease, Death, Demography, Actuarial science, Gerontology, Longevity

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Despite their strong increase, the population of the very old, including near-centenarians and centenarians, represent an unstudied and underserved population. Available studies mostly concentrate on predictors of exceptional longevity, but rarely extend their focus to other areas of functioning. Also, little is known about what contributes to experiencing a quality life in very old age. The present population-based study aims at providing a comprehensive picture of key domain of functioning, including physical, cognitive, social and mental function in very old individuals and to determine predictors of mental health indicators.

Concepts: Sociology, Gerontology, Old age, Ageing, New York City, New York, Longevity, Centenarian

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With increased longevity and more women becoming centenarians, management of the menopause and postreproductive health is of growing importance as it has the potential to help promote health over several decades. Women have individual needs and the approach needs to be personalised. The position statement provides a short integral guide for all those involved in menopausal health. It covers diagnosis, screening for diseases in later life, treatment and follow-up.

Concepts: Menopause, Estrogen, Longevity

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Purpose in life (PIL), a feeling of meaning and direction in life, is associated with favorable health outcomes including lower mortality and reduced risk of disease, disability, and cognitive impairment. Since centenarian offspring have been shown to have long health spans we sought to examine whether they have higher PIL than individuals without familial longevity.

Concepts: Epidemiology, Death, Demography, Actuarial science, Meaning of life, Personal life, Longevity, Purpose

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The scope and purpose of this review was to summarize the aims, methods, findings, and future of centenarian and (semi)-supercentenarian studies in Japan, particularly those from our own interdisciplinary laboratory. Medically, approximately 97% of centenarians contract chronic diseases including hypertension and gastrointestinal disease; however, they present with few cardiovascular risk factors. The low prevalence of diabetes mellitus and carotid atherosclerotic plaques are peculiarities of centenarians, which could be associated with high adiponectin levels. While conducting the Tokyo centenarian study (TCS), we found that only 20% of centenarians enjoyed physical and cognitive independence at the age of 100 years, although most remained independent in daily living until into their 90s. Those who maintained physical independence at 100 years of age were highly likely to become semi-supercentenarians (over 105 years) or even supercentenarians (beyond 110 years). We also describe parts of results of the Japan Semi-supercentenarian Study (JSS), which showed that the suppression of chronic inflammation is an important driver of successful aging at extreme old age. Telomere maintenance and an extremely low frequency of APOE-ε4 alleles are genetic peculiarities of (semi)-supercentenarians. The available data confirm our conviction that semi-supercentenarians are a more appropriate model for the study of human longevity.

Concepts: Inflammation, Senescence, Myocardial infarction, Atherosclerosis, Diabetes mellitus, Cardiovascular disease, Metabolic syndrome, Longevity