Survival In Old Age Research Articles

Childhood living conditions, education and health among the oldest old in Sweden

ABSTRACTThe objectives were to investigate the associations between social and financial living conditions in childhood, education and morbidity in old age. The study population (N = 591; 76+ years old) was assembled from two nationally representative Swedish surveys, in 1968 and 2011, that together made longitudinal analysis possible. Morbidity in old age comprised self-reported measures of musculoskeletal disorders, cardiovascular disease, self-rated health and impaired mobility. There were no independent associations between adverse childhood living conditions and morbidity. However, adverse childhood living conditions were associated with an increased likelihood of low education. Moreover, low education was associated with a higher probability of health problems in old age. The results did not show any associations between adverse childhood conditions and late-life morbidity. However, adverse childhood conditions were associated with lower levels of education which, in turn, was associated with health problems and attrition from the study. These results suggest that adverse childhood conditions may indeed be associated with health and survival in old age, but mainly through mechanisms acting earlier in the lifecourse.

Gender differences in survival in old age.

Although increased survival among females is observed throughout much of adult life, supporting evidence among the oldest old is lacking. We examined the hypothesis that gender differences in survival diminish with advancing age. The Jerusalem Longitudinal Study follows a representative cohort born 1920-1921, comprehensively assessed at ages 70, 78, 85, and 90 (n=463, 927, 1224, and 673, respectively). Mortality data were collected during 1990-2013. Kaplan-Meier survival curves and mortality hazards ratios (HRs) were determined, adjusting for gender, marital status, education, loneliness, self-rated health, physical activity, functional status, neoplasm, diabetes mellitus, hypertension, and ischemic heart disease. Survival between ages 70-78 was 77.3% (n=358/463), 78-85 was 68.9% (n=635/927), 85-90 years was 71.1% (n=870/1224), and 90-93 years was 80.5% (n=542/673). With advancing age, the survival advantage among females versus men declined-at ages 70-78 (85.6% vs. 71%, p<0.0001), 78-85 (74% vs. 63%, p=0.001), 85-90 (74% vs. 67.5%, p=0.06), and 90-93 (80% vs. 81%, p=0.92). Compared to females (HR=1.0), the adjusted HR for male mortality at ages 70-78 was 2.93 (95% confidence interval [CI] 1.75-4.91), ages 78-85 was 2.1 (95% CI 1.5-2.92), ages 85-90 was 1.6 (95% CI 1.2-2.2), and ages 90-93 was 1.1 (95% CI 0.7-1.8). Our findings confirm the hypothesis that the increased longevity observed among females at age 70 gradually diminishes with advancing age, and disappears beyond age 90.

Identification of a prognostic signature for old-age mortality by integrating genome-wide transcriptomic data with the conventional predictors: the Vitality 90+ Study.

BackgroundPrediction models for old-age mortality have generally relied upon conventional markers such as plasma-based factors and biophysiological characteristics. However, it is unknown whether the existing markers are able to provide the most relevant information in terms of old-age survival or whether predictions could be improved through the integration of whole-genome expression profiles.MethodsWe assessed the predictive abilities of survival models containing only conventional markers, only gene expression data or both types of data together in a Vitality 90+ study cohort consisting of n = 151 nonagenarians. The all-cause death rate was 32.5% (49 of 151 individuals), and the median follow-up time was 2.55 years.ResultsThree different feature selection models, the penalized Lasso and Ridge regressions and the C-index boosting algorithm, were used to test the genomic data. The Ridge regression model incorporating both the conventional markers and transcripts outperformed the other models. The multivariate Cox regression model was used to adjust for the conventional mortality prediction markers, i.e., the body mass index, frailty index and cell-free DNA level, revealing that 331 transcripts were independently associated with survival. The final mortality-predicting transcriptomic signature derived from the Ridge regression model was mapped to a network that identified nuclear factor kappa beta (NF-κB) as a central node.ConclusionsTogether with the loss of physiological reserves, the transcriptomic predictors centered around NF-κB underscored the role of immunoinflammatory signaling, the control of the DNA damage response and cell cycle, and mitochondrial functions as the key determinants of old-age mortality.

Employment Dynamics and Redistributive Policies Under Workers' Social Norms

We study employment dynamics using an OLG model with unemployment benefits and universal old-age survival pensions, both financed by taxing employed workers. The novelty is that we explicitly introduce workers' social norms that shape both the individual participation decision of workers and wage bargaining. We find that social norms increase the likelihood of multiplicity of equilibria and somewhat facilitate the emergence of indeterminacy and flip bifurcations, constituting therefore a source of business cycles driven by self-fulfilling volatile expectations, i.e. sunspots. We also find that, in the presence of strong social norms, standard policy recommendations that advocate a decrease in unemployment benefits in order to boost employment are no longer valid. Indeed, our simulation results show that the opposite will happen for empirically plausible levels of the unemployment rate.

Total Daily Physical Activity and Longevity in Old Age

To the Editor Increased levels of exercise are currently recommended to improve health and increase longevity, but gaps in our knowledge impede the formulation of evidence-based recommendations particularly in older individuals.1 In particular, most studies of physical activity in old age have focused on self-reported physical activity measures which are affected by recall bias. Moreover, few studies have examined the contribution of non-exercise physical activity to survival in old age.2–4 We tested the hypothesis that an objective measure of total daily activity, including both exercise and non-exercise physical activity, is associated with longevity in community-dwelling older persons.

Effect of Cholesterol on Mortality and Quality of Life up to a 46-Year Follow-Up

The effect of cholesterol level on the health of older people is a matter of debate, probably because of the bidirectional association. We investigated this paradox in a long-term study. The baseline assessments of the Helsinki Businessmen Study (a cohort of mainly business executives, born 1919 to 1934) included the total cholesterol value and other cardiovascular risk factors from 1964 to 1973. These men were followed up for ≤46 years (through January 2010). During the follow-up period, the cholesterol value was assessed by self-report in 2000 (n = 1,292). Mortality was ascertained from the national registers, symptoms, and health-related quality of life with RAND-36 from questionnaires in 2000. A total of 3,277 healthy men without chronic diseases at baseline were included in the analyses. The median total cholesterol concentration at baseline was 6.5 mmol/L (251 mg/dl) (interquartile range 5.8 to 7.3 mmol/L, 224 to 282 mg/dl) and, in 2000, was 5.2 mmol/L (201 mg/dl) (interquartile range 4.6 to 5.9 mmol/L, 178 to 228 mg/dl). During the follow-up period, 1,773 men (54%) died. A strong and graded relation was found between the cholesterol level and total mortality, with the men with a cholesterol level ≤4 mmol/L (154 mg/dl) having the lowest mortality. In all, the men with the lowest cholesterol gained the most life years. However, no association was found with the cholesterol level in 2000 (when 16% were using statins) and subsequent mortality. The lowest (≤4 mmol/L) cholesterol value in midlife also predicted a higher score in the physical functioning scale of RAND-36 in old age. In conclusion, a low total cholesterol value in midlife predicts both better survival and better physical functioning in old age.

Prognostic significance of serum cholesterol, lathosterol, and sitosterol in old age; a 17-year population study

Background. Low serum total cholesterol is frequently associated with worse survival in older people, but mechanisms of this association are poorly understood.Aims. Characteristics of cholesterol metabolism were related to survival in a random 75 + population sample.Methods. Serum cholesterol and lathosterol, and sitosterol were measured in random persons (n = 623) of birth cohorts (1904, 1909, and 1914) in 1990, and all persons were followed for 17 years.Results. Total cholesterol declined in old age, and low cholesterol was associated with poor health and multi-morbidity. Cholesterol below 5.0 mmol/L was associated with accelerated all-cause mortality (age- and gender-adjusted hazard ratio (HR) 1.54; 95% CI 1.21–1.97; P < 0.001) and vascular mortality (HR 2.13 (1.42–3.07); P < 0.001). Lathosterol (indicating cholesterol synthesis) and sitosterol (indicating cholesterol absorption) also decreased with deteriorating health. Low lathosterol, sitosterol, and cholesterol predicted mortality additively and independently of each other. When all three sterols were high (> median) or low, the age- and gender-adjusted survival was 9.9 and 5.6 years (P < 0.001).Conclusion. Lower synthesis and absorption of cholesterol, and low serum cholesterol level are associated with deteriorating health and indicate impaired survival in old age.

Nutritional concerns, health and survival in old age.

The ageing process is—apart from chance or good luck—not only influenced by factors intrinsic to the individual, but also by extrinsic factors that include environmental and lifestyle variables. This paper deals with the epidemiological evidence for the role of dietary patterns and key nutritional concerns in relation to survival and ageing related disorders that present themselves in later life. Dietary patterns, such as the Mediterranean diet, characterized by mainly plant foods including protective factors e.g. vegetables, nuts and monounsaturated fatty acids and excluding harmful factors e.g. trans-fatty acids and foods with a high glycemic factor, appear to be relevant even in old age. Specific nutritional concerns focus on general undernutrition, vitamin D and vitamin B12. Prevalence of nutritional inadequacies, diagnostic criteria, causes and health consequences are described. The paper ends with recommendations for guidance on healthy diets for elderly people. An important challenge should be research to further expand the knowledge base, acknowledging the complexity of the ageing process and integrating different dimensions of research into human healthy ageing in properly designed studies. In the mean time reversing poor adherence to existing guidelines for a healthy diet remains a first challenge in public health nutritional practices.

Occupational career and risk of mortality among US Civil War veterans.

Previous studies have extended the traditional framework on occupational disparities in health by examining mortality differentials from a career perspective. Few studies, however, have examined the relation between career and mortality in a historical U.S. population. This study explores the relation between occupational career and risk of mortality in old age among 7096 Union Army veterans who fought the American Civil War in the 1860s. Occupational mobility was commonplace among the veterans in the postbellum period, with 54% of them changing occupations from the time of enlistment to 1900. Among veterans who were farmers at enlistment, 46% of them changed to a non-farming occupation by the time of 1900. Results from the Cox Proportional Hazard analysis suggest that relative to the average mortality risk of the sample, being a farmer at enlistment or circa 1900 are both associated with a lower risk of mortality in old age, although the effect is more salient for veterans who were farmers at enlistment. Occupational immobility for manual labors poses a serious threat to chance of survival in old age. These findings still hold after adjusting for the effects of selected variables characterizing risk exposures during early life, wartime, and old age. The robustness of the survival advantage associated with being a farmer at enlistment highlights the importance of socioeconomic conditions early in life in chance of survival at older ages.

The spillover effects of population aging, international capital flows, and welfare

This paper considers how a rise in old-age survival probability in a country with a higher old-age dependency ratio (the home country) influences the welfare of a country with a lower old-age dependency ratio (the foreign country). In a dynamically efficient steady-state equilibrium, we show that the old-age survival probability in the home country, when relatively low (high), has a positive (negative) effect on the welfare of the foreign country. We also show that the reform of a social security program in the home country may improve not only domestic welfare but also the welfare of the foreign country.

Cognition and survival in a biracial urban population of old people

We examined the relation of level of cognition to survival in a biracial community population of more than 10,000 older persons. At baseline, participants completed 4 cognitive tests from which a composite global cognitive measure was derived. During up to 14 years of follow-up (mean=6.9 years), 4201 people died (41.6%). Higher level of cognitive function was associated with increased survival even after controlling for health related and lifestyle variables. The association did not differ between African Americans and whites; it was stronger in older than younger persons; and it was especially pronounced for perceptual speed. The results underscore the importance of cognition to survival in old age.

All-cause mortality in the Aberdeen 1921 birth cohort: effects of socio-demographic, physical and cognitive factors.

BackgroundChildhood intelligence predicts mortality throughout most of the life span. However, it is unknown whether its effect persists into advanced old age.MethodsThe Aberdeen Birth Cohort born in 1921 (n = 354) and that had an IQ test as part of the national Scottish Mental Survey of 1932 were seen in 1997 at age 76 years when childhood and adult socio-environmental, medical and cognitive data were collected. Participants were followed until May 2007 and vital status determined from the General Register for Scotland records. Univariate associations between baseline variables and mortality were determined and multivariable survival analysis performed with Cox's proportional hazards modelling.ResultsOne hundred and fifty-eight (44.6%) of the 354 cohort members had died by the census date. Significantly more men (n = 102) died during follow-up than women (n = 56, χ2 = 5.27, p = .022). Lower scores on four of the six cognitive tests at age 76 years were associated with increased mortality, but not IQ age 11. Survival was associated with gender (H.R. 0.32, 95% C.I. 0.11–0.89 for women versus men), peak expiratory flow rate (H.R. 0.997, 95% C.I. 0.992–1.001 per l/min) and the Uses of Common Objects test (H.R. 0.91, 95% C.I. 0.82–1.01)ConclusionBoth physical and psychological variables independently predicted survival in old age: respiratory function and executive function in particular. Male gender conferred increased risk of mortality and this was not explained by the broad range of socio-environmental, mental ability and health status variables examined in the study.

Sociality, selection, and survival: Simulated evolution of mortality with intergenerational transfers and food sharing

Why do humans survive so long past reproductive age, and why does juvenile mortality decline after birth, both contrary to the classic theory of aging? Previous work has shown formally that intergenerational transfers can explain both these patterns. Here, simulations confirm those results under weaker assumptions and explore how different social arrangements shape life-history evolution. Simulated single-sex hunter-gatherers survive, forage, reproduce, and share food with kin and nonkin in ways guided by the ethnographic literature. Natural selection acts on probabilistically occurring deleterious mutations. Neither stable population age distributions nor homogeneous genetic lineages are assumed. When food is shared only within kin groups, an infant death permits reallocation of its unneeded food to the infant's kin, offsetting the fitness cost of the death and weakening the force of selection against infant mortality. Thus, evolved infant mortality is relatively high, more so in larger kin groups. Food sharing with nonkin reduces the costs to kin of child rearing, but also reduces the resources recaptured by kin after an infant death, so evolved infant mortality is lower. Postreproductive adults transfer food to descendants, enhancing their growth and survival, so postreproductive survival is selected. The force of selection for old-age survival depends in complicated ways on the food-sharing arrangements. Population-level food sharing with nonkin leads to the classic pattern of constant low mortality up to sexual maturity and no postreproductive survival.

Thyroid Status and Survival in Old Age—Reply

Thyroid Status and Survival in Old Age—Reply

Thyroid Status and Survival in Old Age

Thyroid Status and Survival in Old Age

Thyroid Status and Survival in Old Age

Thyroid Status and Survival in Old Age

Should subclinical hypothyroidism in elderly patients be treated?

Gussekloo J, van Exel E, de Craen AJM, Meinders AE, Frolich M, Westendorp RGJ. Thyroid status, disability and cognitive function, and survival in old age. JAMA 2004;292:2591-9. Background: Subclinical hypothyroidism is defined as a normal serum free thyroxine level combined with an elevated

Body mass index and old-age survival: A comparative study between the Union Army Records and the NHANES-I Epidemiological Follow-Up Sample

On the basis of a historical review of the BMI trend among white male Americans since the late 19th century, this paper investigates the association between BMI measured at age 50-59 years and survival in the subsequent 18 years of follow-up through a comparative study between the Union Army Records (n = 1,238) and the 1971-1975 National Health and Nutritional Examination Survey Epidemiological Follow-up Sample (n = 861). A descriptive analysis of the trend in BMI suggests that the age-adjusted average BMI among adult white males has increased from 22.8 in the late 19th century to 28.0 in the year of 2000. The corresponding increase in the age-adjusted percentage of obesity is from 2.5% to 28.2%. Given the significant increase in BMI, it becomes important to evaluate how the BMI-mortality association has changed since the 19th century, and what implications these changes might have to mortality in the future. The results from the Cox proportional hazard analysis indicate that as the average BMI at population level increases, the optimal BMI in terms of survival increases, rather than stable. With the whole American population moving into a higher BMI regime, the optimal BMI in terms of old-age survival for white male Americans has experienced a substantial upward shift, from 20.6-23.6 in the late 19th century to 22.7-27.3 in the early 1970s. Mortality differentials across BMI quintiles have become more salient since the late 19th century. There is still good potential for old-age mortality to further decline. However, to what extent this potential can be developed will partially depend on the future trend in the prevalence of obesity.

Thyroid Status, Disability and Cognitive Function, and Survival in Old Age

Despite the equivocal outcomes of randomized controlled trials, general clinical opinion favors screening and treatment of elderly individuals with subclinical thyroid disorders. To determine whether subclinical thyroid dysfunction should be treated in old age and the long-term impact of thyroid dysfunction on performance and survival in old age. A prospective, observational, population-based follow-up study within the Leiden 85-Plus Study of 87% of a 2-year birth cohort (1912-1914) in the municipality of Leiden, the Netherlands. A total of 599 participants were followed up from age 85 years through age 89 years (mean [SD] follow-up, 3.7 [1.4] years). Complete thyroid status at baseline; disability in daily life, depressive symptoms, cognitive function, and mortality from age 85 years through 89 years. Plasma levels of thyrotropin and free thyroxine were not associated with disability in daily life, depressive symptoms, and cognitive impairment at baseline or during follow-up. Increasing levels of thyrotropin were associated with a lower mortality rate that remained after adjustments were made for baseline disability and health status. The hazard ratio (HR) for mortality per SD increase of 2.71 mIU/L of thyrotropin was 0.77 (95% confidence interval [CI], 0.63-0.94; P = .009). The HR for mortality per SD increase of 0.21 ng/dL (2.67 pmol/L) of free thyroxine increased 1.16-fold (95% CI, 1.04-1.30; P = .009). In the general population of the oldest old, elderly individuals with abnormally high levels of thyrotropin do not experience adverse effects and may have a prolonged life span. However, evidence for not treating elderly individuals can only come from a well-designed, randomized placebo-controlled clinical trial.

The role of NGF uptake in selective vulnerability to cell death in ageing sympathetic neurons

We have examined the hypothesis that differences in nerve growth factor (NGF) uptake and transport determine vulnerability to age-related neurodegeneration. Neurons projecting to cerebral blood vessels (CV) in aged rats are more vulnerable to age-related degeneration than those projecting to the iris. Uptake of NGF was therefore examined in sympathetic neurons projecting from the superior cervical ganglion (SCG) to CV and iris in young and old rats by treating the peripheral processes of these neurons with different doses of I125-NGF. Total uptake of I125-NGF was reduced in old CV-projecting, but not iris-projecting, neurons. Numbers of radiolabelled neurons projecting to each target were counted in sectioned ganglia. The data showed age-related reductions in numbers of labelled neurons projecting to CV, but no change in numbers of neurons projecting to the iris. Calculation of uptake of I125-NGF per neuron unexpectedly showed no major age-related differences in either of the two neuron populations. However, uptake per neuron was considerably lower for young and old CV-projecting, compared to iris-projecting, SCG neurons. We hypothesized that variations in NGF uptake might affect neuronal survival in old age. Counts of SCG neurons using a physical disector following retrograde tracing with Fluorogold confirmed the selective vulnerability of CV-projecting neurons by showing a significant 37% loss of these neurons in the period between 15 and 24 months. In contrast, there was no significant loss of iris-projecting neurons. We conclude that vulnerability to, or protection from, age-related neurodegeneration and neuronal cell death are associated with life-long low, or high, levels of NGF uptake, respectively.