Demographic perspectives on the rise of longevity.

This article reviews some key strands of demographic research on past trends in human longevity and explores possible future trends in life expectancy at birth. Demographic data on age-specific mortality are used to estimate life expectancy, and validated data on exceptional life spans are used to study the maximum length of life. In the countries doing best each year, life expectancy started to increase around 1840 at a pace of almost 2.5 y per decade. This trend has continued until the present. Contrary to classical evolutionary theories of senescence and contrary to the predictions of many experts, the frontier of survival is advancing to higher ages. Furthermore, individual life spans are becoming more equal, reducing inequalities, with octogenarians and nonagenarians accounting for most deaths in countries with the highest life expectancy. If the current pace of progress in life expectancy continues, most children born this millennium will celebrate their 100th birthday. Considerable uncertainty, however, clouds forecasts: Life expectancy and maximum life span might increase very little if at all, or longevity might rise much faster than in the past. Substantial progress has been made over the past three decades in deepening understanding of how long humans have lived and how long they might live. The social, economic, health, cultural, and political consequences of further increases in longevity are so significant that the development of more powerful methods of forecasting is a priority.

A modal age at death approach to forecasting adult mortality.

Recent studies have shown that there are some advantages to forecasting mortality with indicators other than age-specific death rates. The mean, median, and modal ages at death can be directly estimated from the age-at-death distribution, as can information on lifespan variation. The modal age at death has been increasing linearly since the second half of the twentieth century, providing a strong basis from which to extrapolate past trends. The aim of this paper is to develop a forecasting model that is based on the regularity of the modal age at death and that can also account for changes in lifespan variation. We forecast mortality at ages 40 and above in 10 West European countries. The model we introduce increases forecast accuracy compared with other forecasting models and provides consistent trends in life expectancy and lifespan variation at age 40 over time.

Effect of measuring vital signs on recognition and treatment of septic children.

BACKGROUND AND OBJECTIVES: A majority of children presenting with sepsis do not receive adequate fluid resuscitation and have a delay in antibiotic administration despite recommendations from the Surviving Sepsis Campaign. The objective of this study was to evaluate the association of measuring a complete set of five vital signs in the emergency department (ED) with recognition and treatment of septic children presenting to the ED. METHODS: Records of 218 patients aged 1 month to 17 years treated between February 2011 and December 2011 in a single academic centre with clinical criteria of sepsis, severe sepsis or septic shock were retrospectively evaluated. The presence or absence of complete vital signs was analyzed in relation to timing of fluid resuscitation, and if antibiotics were given in the first hour of medical evaluation. RESULTS: Seventy-six per cent of children who had all five vital signs measured in the ED received fluid resuscitation in the first hour after medical evaluation as opposed to 61% of those who had an incomplete set of vital signs (P<0.04). Twenty per cent of children who had all five vital signs measured received antibiotics in the first hour as opposed to 9% in children who had fewer vital signs measured (P<0.02). CONCLUSION: In our study population, the measurement of all vital signs in the ED, including blood pressure, was associated with faster administration of antibiotics and improved compliance with existing fluid bolus recommendations, which may have been the result of better recognition of sepsis in children through vital signs measurement.

L'effet de la mesure des signes vitaux pour dépister et traiter les enfants atteints de sepsis. HISTORIQUE ET OBJECTIFS: La majorité des enfants ayant un sepsis ne reçoivent pas de solutés de réanimation et doivent attendre avant de se faire administrer des antibiotiques, malgré les recommandations de la Surviving Sepsis Campaign. La présente étude visait à évaluer l'association entre la mesure de l'ensemble des cinq signes vitaux à la salle d'urgence (SU) et le dépistage et le traitement des enfants atteints de sepsis qui s'y présentaient. MÉTHODOLOGIE: Les dossiers de 218 patients de 11 mois à 17 ans traités entre février et décembre 2011 dans un seul centre universitaire en raison de critères cliniques de sepsis, de grave sepsis ou de choc septique ont fait l'objet d'une évaluation rétrospective. Les chercheurs ont analysé le lien entre la présence ou l'absence de tous les signes vitaux et le moment d'administrer des solutés de réanimation et ont vérifié si des antibiotiques avaient été administrés dans l'heure suivant l'évaluation médicale. RÉSULTATS: Au total, 76 % des enfants dont les cinq signes vitaux avaient été mesurés à la SU avaient reçu des solutés de réanimation dans l'heure suivant leur évaluation médicale, par rapport à 61 % de ceux dont les signes vitaux n'avaient pas tous été mesurés (P<0,04). De plus, 20 % des enfants dont les cinq signes vitaux avaient été mesurés à la SU avaient reçu des antibiotiques dans l'heure suivant leur évaluation médicale, par rapport à 9 % de ceux dont les signes vitaux n'avaient pas tous été mesurés (P<0,02). CONCLUSION: Au sein de la population à l'étude, la mesure de tous les signes vitaux en SU, y compris la tension artérielle, s'associait à une administration plus rapide d'antibiotiques et à une meilleure compliance aux recommandations sur le bolus de liquide, ce qui peut être attribuable à un meilleur dépistage du sepsis chez les enfants grâce à la mesure des signes vitaux.

Inequalities in lifespan and mortality risk in the US, 2015-2019: a cross-sectional analysis of subpopulations by social determinants of health.

OBJECTIVE: To quantify inequalities in lifespan across multiple social determinants of health, how they act in tandem with one another, and to create a scoring system that can accurately identify subgroups of the population at high risk of mortality. DESIGN: Comparison of life tables across 54 subpopulations defined by combinations of four social determinants of health: sex, marital status, education and race, using data from the Multiple Cause of Death dataset and the American Community Survey. SETTING: United States, 2015-2019. MAIN OUTCOME MEASURES: We compared the partial life expectancies (PLEs) between age 30 and 90 years of all subpopulations. We also developed a scoring system to identify subgroups at high risk of mortality. RESULTS: There is an 18.0-year difference between the subpopulations with the lowest and highest PLE. Differences in PLE between subpopulations are not significant in most pairwise comparisons. We visually illustrate how the PLE changes across social determinants of health. There is a complex interaction among social determinants of health, with no single determinant fully explaining the observed variation in lifespan. The proposed scoring system adds clarification to this interaction by yielding a single score that can be used to identify subgroups that might be at high risk of mortality. A similar scoring system by cause of death was also created to identify which subgroups could be considered at high risk of mortality from specific causes. Even if subgroups have similar mortality levels, they are often subject to different cause-specific mortality risks. CONCLUSIONS: Having one characteristic associated with higher mortality is often not sufficient to be considered at high risk of mortality, but the risk increases with the number of such characteristics. Reducing inequalities is vital for societies, and better identifying individuals and subgroups at high risk of mortality is necessary for public health policy.

Forecasting Inequalities in Survival to Retirement Age by Socioeconomic Status in Denmark and Sweden.

In Denmark and Sweden, statutory retirement age is indexed to life expectancy to account for mortality improvements in their populations. However, mortality improvements have not been uniform across different sub-populations. Notably, in both countries, individuals of lower socioeconomic status (SES) have experienced slower mortality improvements. As a result, a uniform rise in the statutory retirement age could disproportionally affect these low-SES groups and may unintentionally lead to a reverse redistribution effect, shifting benefits from short-lived low-SES individuals to long-lived high-SES individuals. The aim of this study is twofold: to quantify and contextualise mortality inequalities by SES in Denmark and Sweden, and to assess how indexing retirement age will affect future survival to retirement age by SES in these countries. We used Danish and Swedish registry data (1988-2019), to aggregate individuals aged 50 + based on their demographic characteristics and SES. We computed period life tables by year, sex, and SES to estimate the difference in survival across different SES groups. We then forecast mortality across SES groups to assess how indexing retirement age will affect survival inequalities to retirement age, using two forecasting models-the Mode model and the Li-Lee model. Mortality inequalities are comparable in Denmark and Sweden, even though the latter generally has higher survival. We also find that indexing retirement age to life expectancy will have two main consequences: it will reduce the probability of reaching retirement for all SES groups, particularly those of low SES, and time spent in retirement will be reduced, particularly for those of high SES.

Probability of males to outlive females: an international comparison from 1751 to 2020.

OBJECTIVE: To measure sex differences in lifespan based on the probability of males to outlive females. DESIGN: International comparison of national and regional sex-specific life tables from the Human Mortality Database and the World Population Prospects. SETTING: 199 populations spanning all continents, between 1751 and 2020. PRIMARY OUTCOME MEASURE: We used the outsurvival statistic ( φ ) to measure inequality in lifespan between sexes, which is interpreted here as the probability of males to outlive females. RESULTS: In random pairs of one male and one female at age 0, the probability of the male outliving the female varies between 25% and 50% for life tables in almost all years since 1751 and across almost all populations. We show that φ is negatively correlated with sex differences in life expectancy and positively correlated with the level of lifespan variation. The important reduction of lifespan inequality observed in recent years has made it less likely for a male to outlive a female. CONCLUSIONS: Although male life expectancy is generally lower than female life expectancy, and male death rates are usually higher at all ages, males have a substantial chance of outliving females. These findings challenge the general impression that 'men do not live as long as women' and reveal a more nuanced inequality in lifespans between females and males.

Diversification in causes of death in low-mortality countries: emerging patterns and implications.

INTRODUCTION: An important role of public health organisations is to monitor indicators of variation, so as to disclose underlying inequality in health improvement. In industrialised societies, more individuals than ever are reaching older ages and have become more homogeneous in their age at death. This has led to a decrease in lifespan variation, with substantial implications for the reduction of health inequalities. We focus on a new form of variation to shed further light on our understanding of population health and ageing: variation in causes of death. METHODS: Data from the WHO Mortality Database and the Human Mortality Database are used to estimate cause-of-death distributions and life tables in 15 low-mortality countries. Cause-of-death variation, using 19 groups of causes, is quantified using entropy measures and analysed from 1994 to 2017. RESULTS: The last two decades have seen increasing diversity in causes of death in low-mortality countries. There have been important reductions in the share of deaths from diseases of the circulatory system, while the share of a range of other causes, such as diseases of the genitourinary system, mental and behavioural disorders, and diseases of the nervous system, has been increasing, leading to a more complex cause-of-death distribution. CONCLUSIONS: The diversification in causes of death witnessed in recent decades is most likely a result of the increase in life expectancy, together with better diagnoses and awareness of certain diseases. Such emerging patterns bring additional challenges to healthcare systems, such as the need to research, monitor and treat a wider range of diseases. It also raises new questions concerning the distribution of health resources.

Understanding Differences in Cancer Survival between Populations: A New Approach and Application to Breast Cancer Survival Differentials between Danish Regions.

Large variations in cancer survival have been recorded between populations, e.g., between countries or between regions in a country. To understand the determinants of cancer survival differentials between populations, researchers have often applied regression analysis. We here propose the use of a non-parametric decomposition method to quantify the exact contribution of specific components to the absolute difference in cancer survival between two populations. Survival differences are here decomposed into the contributions of differences in stage at diagnosis, population age structure, and stage-and-age-specific survival. We demonstrate the method with the example of differences in one-year and five-year breast cancer survival between Denmark's five regions. Differences in stage at diagnosis explained 45% and 27%, respectively, of the one- and five-year survival differences between Zealand and Central Denmark for patients diagnosed between 2008 and 2010. We find that the introduced decomposition method provides a powerful complementary analysis and has several advantages compared with regression models: No structural or distributional assumptions are required; aggregated data can be used; and the use of absolute differences allows quantification of the survival that could be gained by improving, for example, stage at diagnosis relative to a reference population, thus feeding directly into health policy evaluation.

Modeling and forecasting sex differences in mortality: a sex-ratio approach.

Female and male life expectancies have converged in most industrialized societies in recent decades. To achieve coherent forecasts between females and males, this convergence needs to be considered when forecasting sex-specific mortality. We introduce a model forecasting a matrix of the age-specific death rates of sex ratio, decomposed into two age profiles and time indices-before and after age 45-using principal component analysis. Our model allows visualization of both age structure and general level over time of sex differences in mortality for these two age groups. Based on a prior forecast for females, we successfully forecast male mortality convergence with female mortality. The usefulness of the developed model is illustrated by its comparison with other coherent and independent models in an out-of-sample forecast evaluation for 18 countries. The results show that the new proposal outperformed the other models for most countries.

Liver metabolic disruption induced after a single exposure to PCB126 in rats.

Polychlorinated biphenyls (PCBs) have been recognized as metabolic disruptors. The liver plays a pivotal role in detoxification of an organism. Fatty liver results from altered intra-, and extra-hepatic mediators and is associated with increased glucose-related protein 78 (GRP78), commonly used as a marker for endoplasmic reticulum (ER) stress signaling. This pilot study aimed to study the effects of a single exposure on fatty liver metabolic parameters. The objective of the study is to characterize the effects of 3,3',4,4',5-pentachlorobiphenyl (PCB126) on ER stress protein chaperon GRP78 and CCAAT-enhancer-binding protein homologous protein (CHOP) and intra-hepatic mediators such as microsomal triglyceride transfer protein (MTP), sterol regulatory element-binding protein 1c (SREBP1c), and peroxisome proliferator-activated receptor alpha (PPARα), as well as extra-hepatic factors such as non-esterified fatty acid (NEFA) and tumor necrosis factor alpha (TNFα). Hepatic GRP78 mRNA and protein levels, indicating the presence of ER stress, were significantly increased following a single PCB126 exposure in rats. Intra-hepatic mechanisms such as lipoprotein secretion pathway (i.e., MTP), lipogenesis de novo (i.e., SREBP1c), and oxidation (i.e., PPARα) were altered in PCB126-treated rats. In addition, a state of inflammation measured by higher TNFα plasma levels was present in contaminated rats. These data indicate that a single injection of PCB126-modulated expression of GRP78 associated with hepatic ER stress and systemic inflammation in rats.

The effects of PCB126 on intra-hepatic mechanisms associated with non alcoholic fatty liver disease.

BACKGROUND: Non alcoholic fatty liver disease (NAFLD) results from alteration in lipid synthesis and elimination mechanisms such as very-low density lipoprotein (VLDL) production and de novo lipogenesis. Persistent organic pollutants (POPs) are chemicals that were mostly used historically as pesticides, solvents, flame retardant, and other applications. Among POPs, polychlorinated biphenyls (PCB) have been recognized to be of environmental and potential toxicologic concerns. Specifically, PCB126 could act as endocrine disruptors and has recently been associated with hepatic fat accumulation. The purpose of the study was to investigate the effects of PCB126 on the molecular development of NAFLD using hepatocyte and rat models. METHODS: Hepatocytes were exposed to PCB 126 for 72 h and lipid accumulation in cells was quantified by Oil-Red-O. Rats were injected with a single dose of PCB126 or vehicle. Seven days later, liver triglycerides (TAG) content was measured along with protein quantification of hepatic microsomal triglyceride transfer protein (MTP), sterol regulatory element-binding protein 1c (SREBP1c) and diacylglycerol O-acyltransferase 2 (DGAT-2). RESULTS: Exposure to PCB126 resulted in significant increases of lipid accumulation in hepatocytes (38 %, P <0.05) and hepatic TAG concentrations (64 %, P <0.001) in rats compared to respective control groups. Rats with fatty livers depicted lower MTP (40 %, P <0.02), higher SREBP1c (27 %, P < 0.05) and DGAT-2 (120 %, P < 0.02) protein content levels compared to Placebo group in rats. CONCLUSIONS: It seems that exposure to PCB126 has an important emerging role in the pathophysiology of NAFLD by 1) altering elimination mechanisms such as VLDL synthesis and secretion, through MTP; and 2) increasing hepatic TAG synthesis mechanisms through DGAT 2 and SREBP1c.

[Who will be the first-born baby boomers at risk of financial vulnerability in retirement? A comparison of Quebec and Ontario]. / Qui seront les premiers nés du baby-boom à risque de vulnérabilité financière à la retraite? Une comparaison Québec-Ontario.

The oncoming retirement of baby boomers has governments worried. Will individual baby boomers demonstrate the ability to prepare financially for their retirement? Well-being in retirement depends largely on financial preparedness during working life. Those baby boomers who are the most vulnerable at the end of their working lives are more likely to become vulnerable during retirement. This study looks at the income of the first baby boomers, those born between 1946 and 1956, aged 50 to 60, according to the 2006 Canadian census. First we establish the socio-economic categories for which members are most financially vulnerable. Then, we estimate how many baby boomers are vulnerable and to what extent. This study's preferred approach is an interprovincial comparison between Quebec and Ontario, used to analyze individual aspects of baby boomers' financial positions.