Mortality by education level at late-adult ages in Turin: a survival analysis using frailty models with period and cohort approaches

OBJECTIVES: Neglecting the presence of unobserved heterogeneity in survival analysis models has been showed to potentially lead to underestimating the effect of the covariates included in the analysis. This study aimed to investigate the role of unobserved heterogeneity of frailty on the estimation of mortality differentials from age 50 on by education level. DESIGN: Longitudinal mortality follow-up of the census-based Turin population linked with the city registry office. SETTING: Italian North-Western city of Turin, observation window 1971–2007. POPULATION: 391 170 men and 456 216 women followed from age 50. PRIMARY OUTCOME MEASURES: Mortality rate ratios obtained from survival analysis regression. Models were estimated with and without the component of unobserved heterogeneity of frailty and controlling for mortality improvement over time from both cohort and period perspectives. RESULTS: In the majority of cases, the models without frailty estimated a smaller educational gradient than the models with frailty. CONCLUSIONS: The results draw the attention of the potential underestimation of the mortality inequalities by socioeconomic levels in survival analysis models when not controlling for unobserved heterogeneity of frailty

Health care system efficiency and life expectancy: A 140-country study.

Despite the evidence of links between health expenditure and health care efficiency, it is still unclear why countries with similar levels of health expenditures experience different outputs in terms of life expectancy at birth. Health care system efficiency might shed some light on the question. Using output-oriented data envelopment analysis, we compared the health systems of 140 countries in terms of attained life expectancy. Efficiency is determined by the distance from the closest country on the best practice frontier, which identifies the highest attainable life expectancy observed for any given level of health care spending. By using national data form the Human Development Data, we built the efficiency frontier and computed the potential life expectancy increase for each country. The potential improvement was, on average, 5.47 years [95%CI: 4.71-6.27 years]. The least efficient countries (10th percentile of the efficiency score) could improve by 11.78 years, while the most efficient countries (90th percentile of the efficiency score) could only improve by 0.83 years. We then analyzed, with regression analysis stratified by average education level, and by the role of health-related variables in differentiating efficient and inefficient countries from each other. The results suggest that, among countries with lower levels of education, decreasing unemployment and income inequality increases average life expectancy, without increasing health expenditure levels

Fertility decline and the emergence of excess female survival in post-reproductive ages in Italy

In Italy, at least in the cohorts born up to the beginning of the twentieth century, women's mortality in post-reproductive ages was influenced by fertility, with large progenies (and, to a lesser extent, childlessness) leading to markedly lower survival chances. This relationship proved strong enough to affect the female-to-male ratio in old age as fertility declined. In this paper, we show that various measures of extra female survival at high ages are closely connected to the fertility transition in Italy, and to its peculiar historical and geographical evolution

Divergent trends in lifespan variation during mortality crises

Background: Lifespan variation has been attracting attention as a measure of population health and mortality. Several studies have highlighted its strong inverse relationship with life expectancy during periods of steady mortality decline, but this association weakens, and even reverses, when mortality does not improve equally over age. To date no study has comprehensively explored the behaviour of lifespan variation when mortality increases significantly. Objective: We investigate lifespan variation trends around various mortality crises, focusing on age-specific contributions and sex differences. Methods: Drawing data from the Human Mortality Database and Meslé and Vallin’s Ukrainian lifetables, we analyse five European epidemics and famines across three centuries. We use six measures of lifespan variation and adopt the linear integral method of decomposition. Results: During these crises, relative lifespan variation increases, while absolute variation declines, and subsequently both quickly revert to pre-crisis levels. We show that mortality at older ages leads to a temporary increase in absolute – but not relative – variation. The lifespan variation of females is less affected than that of males, because of differences in the impact of infant and child mortality. Conclusions: Even when infant mortality is high, mortality at older ages can influence lifespan variation. Our results also underscore the sex differences in the vulnerability of young individuals in periods of extreme mortality. Contribution: By underlining different trends of lifespan variation by sex and indicator, we offer new insight into the consequences of mortality crises. Contrary to what is often asserted, we show that the choice of lifespan variation indicator is not always inconsequential

Functional data analysis approach in population studies: an application to the gender gap in life expectancy

This work analyses the contribution of ages and causes of death to gender gap in life expectancy in 20 European and non-European countries between 1959 and 2015, using Functional Data Analysis. Data were retrieved from the WHO Mortality Database and from the Human Mortality Database. We propose a Functional Principal Component Analysis of the age profiles of cause-specific contributions, to identify the main components of the distribution of the age-specific contributions according to causes of death, and to summarize them with few components. Our findings show that the narrowing gender gap in life expectancy was mainly driven by decreasing differences in cardiovascular diseases. Additionally, the study reveals that the age cause contributions act almost entirely on only two dimensions: level (extent of the cause-specific contribution to the overall mortality gender gap) and age pattern (location of the curves across ages). Notably, in the last period, it is not the "quantum" of the cause-specific contributions that matters, but the "timing", i.e. location across the age spectrum. Moreover, our results show that in the most recent period the gender gap in life expectancy is affected by composition of the causes of death more than it was in previous periods. We emphasise that Functional Data Analysis could prove useful to deepen our understanding of complex demographic phenomena

Gender differential in mortality in post-reproductive age. The role of the fertility decline in Italy and Europe

Summary: In this paper, we highlight the close link between fertility decline and the emergence of the female survival advantage in post reproductive age (50 years and over). We performed an ecological analysis on the evolution of gender differentials in mortality in 16 Italian administrative regions and in 16 European countries. In both cases, we kept under control the possible confounding effects due to the spreading of smoking, the general decline of mortality, the presence of migration, the outbreak of wars and the diffusion of the obesity pandemics. Two main results emerge. First, the rise of a significant mortality differential between sexes is a relatively recent phenomenon, whose onset dates back to the birth cohorts of the last decades of the 19th century. Second, this phenomenon is associated, at the aggregate level, to the process of fertility decline

Women live longer than men even during severe famines and epidemics

Women in almost all modern populations live longer than men. Research to date provides evidence for both biological and social factors influencing this gender gap. Conditions when both men and women experience extremely high levels of mortality risk are unexplored sources of information. We investigate the survival of both sexes in seven populations under extreme conditions from famines, epidemics, and slavery. Women survived better than men: In all populations, they had lower mortality across almost all ages, and, with the exception of one slave population, they lived longer on average than men. Gender differences in infant mortality contributed the most to the gender gap in life expectancy, indicating that newborn girls were able to survive extreme mortality hazards better than newborn boys. Our results confirm the ubiquity of a female survival advantage even when mortality is extraordinarily high. The hypothesis that the survival advantage of women has fundamental biological underpinnings is supported by the fact that under very harsh conditions females survive better than males even at infant ages when behavioral and social differences may be minimal or favor males. Our findings also indicate that the female advantage differs across environments and is modulated by social factors.</p