Inflammatory exposure and historical changes in human life-spans

Early-Life Disease Exposure and Its Heterogeneous Effects on Mortality Throughout Life: Sweden, 1905-2016

Exposure to infectious diseases in early life has been linked to increased mortality risk in later life in high-disease settings, such as eighteenth- and nineteenth-century Europe. Less is known about the long-term effects of early-life disease exposure in milder disease environments. This study estimates heterogeneous effects from disease exposure in infancy on later-life mortality in twentieth-century Sweden, by socioeconomic status at birth and sex. Using historical population data for southern Sweden, we study 11,515 individuals who were born in 1905-1929 from age 1 until age 85. We measure exposure to disease using the local post-early neonatal mortality rate in the first 12 months after birth and apply flexible parametric survival models. For females, we find a negative effect on life expectancy (scarring) at ages 1-85 following high disease exposure in infancy, particularly for those born to unskilled workers. For males, we find no negative effect on later-life survival, likely because stronger mortality selection in infancy outweighs scarring. Thus, even as the incidence of infectious diseases declined at the start of the twentieth century, early-life disease exposure generated long-lasting negative but heterogeneous population health effects.

Vestiges of famine: Long-term mortality impacts of early-life exposure to the 1840s famine in Estonia

The paper investigates whether exposure to a famine in the Russian Tsarist Province of Livland in 1844-1846 in early life negatively affected survival at later ages, using individual data from two rural parishes. We follow 18 birth cohorts born between 1834-1852 until age 75 and differentiate between timing and length of exposures. We find that relative to individuals born in pre- or post- crisis years, there were no significant differences in survival from age 21-75. Cohorts with longer exposure to famine conditions had increased mortality only in short term, up to age 20. Males were more vulnerable in younger ages than females. The negative effect of adverse early life exposure on survival in later life was constrained to lower social group - the landless, but for the better-off groups the effect was constrained to younger ages. The paper highlights the importance of accounting for sex and socio-economic differences in studies exploring the effects of early life conditions on later-life survival.

Life expectancy in relation to societal development level: significant discordant factors

OBJECTIVES

The aim of this study is to determine the interdependence between life expectancy and numerous social indicators, i.e., to determine the factors that encourage an increase or decrease in life expectancy.

METHODS

Pearson coefficients as well as linear and logarithmic trends and correlations between the dependent variable of life expectancy and numerous independent variables were calculated and analysed. The calculations were carried out for all countries in the world for which data is available. Based on the strength of the correlations between life expectancy and numerous indicators, we have tried to determine the reasons for the different values of life expectancy in the various countries.

RESULTS

Important factors for achieving high life expectancy values are economic development and healthcare spending but the spread of "diseases of the modern era", such as obesity or diabetes, have a significant negative impact on life expectancy. Other important limiting factors for life expectancy are large income inequalities, a higher share of private healthcare expenditure in total healthcare expenditure and lower total healthcare expenditure. Less developed societies can significantly increase their life expectancy by providing clean water and safe sanitation and by combating various infectious diseases (especially HIV).

CONCLUSIONS

Life expectancy is a meaningful indicator of the state of social development and accurately reflects the general state of a particular society. It has been shown that GDP per capita (PPP) is a key determinant of life expectancy, while other important factors play the role of a further modifier.

Disease exposure in infancy affects women's reproductive outcomes and offspring health in southern Sweden 1905-2000

Ample evidence demonstrates that early-life adversity negatively affects morbidity and survival in late life. We show that disease exposure in infancy also has a continuous impact on reproduction and health across the female life course and even affects early-life health of the next generation. Using Swedish administrative data, obstetric records, and local infant mortality rates as a measure of disease exposure, we follow women's reproductive careers and offspring health 1905-2000, examining a comprehensive set of outcomes. Women exposed to disease in infancy give birth to a lower proportion of boys, consistent with notions that male fetuses are more vulnerable to adverse conditions and are more often miscarried. Sons of exposed mothers are also more likely to be born preterm and have higher birthweight suggesting in utero out-selection. Exposed women have a greater risk of miscarriage and of male stillbirth, but their overall likelihood of giving birth is not affected.

Intermittent hypoxia induces hepatic senescence through promoting oxidative stress in a mouse model

PURPOSE

Metabolic-associated fatty liver disease (MAFLD) is an aging-related disease. Obstructive sleep apnea (OSA) may cause MAFLD. This study aimed to explore whether or not intermittent hypoxia (IH), the hallmark of OSA, induces liver aging through oxidative stress.

METHODS

C57BL/6J male mice were administered normal air (control), IH, or antioxidant tempol + IH daily for 6 weeks before the collection of serum and liver tissue samples. A histological examination was conducted to assess liver aging. ELISA was performed to measure liver function indicator levels in the serum and oxidative stress indicator activities in the liver. Western blot analysis was carried out to determine the protein expression of the markers related to oxidative stress, inflammation, and senescence.

RESULTS

Compared with control, IH resulted in significant increases in serum ALT, AST, and TG levels in mice (all P < 0.001), along with lobular inflammation and accumulation of collagen and fat in the liver. The protein levels of inflammatory factors and senescent markers were significantly increased in the IH mouse liver compared with those in the control mouse liver. Meanwhile, IH significantly reduced SOD and CAT activities while enhancing p22phox and Nrf2 protein expression in mouse liver compared with control. Importantly, antioxidant therapy with tempol effectively abrogated the effects of IH on oxidative stress response and aging-related liver injury.

CONCLUSIONS

Our findings suggest that IH induces liver inflammation and aging through oxidative stress. OSA may exacerbate target organ aging and participate in target organ damage. Strategies targeting oxidative stress may prevent and treat OSA-related MAFLD.

Dementia in the Ancient Greco-Roman World Was Minimally Mentioned

Background

The possibility that Alzheimer's disease and related dementias (ADRD) is a modern disease arises from the minimal mention of advanced cognitive decline by ancient Greeks and Romans, who were mainly concerned with the physical frailties of older ages.

Objective

Because standard medical histories of elderly health lacked mention of cognitive decline, we examined texts by Greek and Roman authors that mentioned memory loss and dementia.

Methods

Primary texts of Greco-Roman authors, 8th century BCE into the 3rd century CE, that mentioned cognitive decline were identified and critically evaluated. Secondary sources were excluded.

Results

No ancient account of cognitive loss is equivalent to modern clinical data. The term dementia was occasionally used in antiquity, but not invariably linked to old age. Ancient Greeks and Romans expected intellectual competence beyond age 60. While some memory loss was acknowledged, we found only four accounts of severe cognitive loss that might represent ADRD. The possibility of modest ADRD prevalence in ancient Greece and Rome is consistent with its low prevalence in the Tsimane of Bolivia. These contemporary Amerindians live under conditions of high mortality from frequent infections and minimal cardiovascular disease with physically demanding lives. Tsimane after age 60 had increased mild cognitive impairment; the few cases of dementia were not clinically consistent with AD.

Conclusions

The modern 'epidemic level' of advanced dementias was not described among ancient Greco-Roman elderly. The possible emergence of advanced ADRD in the Roman era may be associated with environmental factors of air pollution and increased exposure to lead. Further historical analysis may formulate critical hypotheses about the modernity of high ADRD prevalence.

The economics of aging with infectious and chronic diseases

We develop an economic model of aging in which the susceptibility and severity of infectious diseases depend on the accumulated health deficits (immunosenescence) and the life history of infections affects the accumulation of chronic health deficits (inflammaging). Individuals invest in their health to slow down health deficit accumulation and take measures to protect themselves from infectious diseases. We calibrate the model for an average American and explore how health expenditure, life expectancy, and the value of life depend on individual characteristics, medical technology, and the disease environment. We then use counterfactual computational experiments of the U.S. epidemiological transition 1860-2010 to show that the decline of infectious diseases caused a substantial decline of chronic diseases and contributed more to increasing life expectancy than advances in the treatment of chronic diseases.

Three common assumptions about inflammation, aging, and health that are probably wrong

Chronic inflammation contributes to the onset and progression of cardiovascular disease and other degenerative diseases of aging. But does it have to? This article considers the associations among inflammation, aging, and health through the lens of human population biology and suggests that chronic inflammation is not a normal nor inevitable component of aging. It is commonly assumed that conclusions drawn from research in affluent, industrialized countries can be applied globally; that aging processes leading to morbidity and mortality begin in middle age; and that inflammation is pathological. These foundational assumptions have shifted focus away from inflammation as a beneficial response to infection or injury and toward an understanding of inflammation as chronic, dysregulated, and dangerous. Findings from community-based studies around the world-many conducted in areas with relatively high burdens of infectious disease-challenge these assumptions by documenting substantial variation in levels of inflammation and patterns of association with disease. They also indicate that nutritional, microbial, and psychosocial environments in infancy and childhood play important roles in shaping inflammatory phenotypes and their contributions to diseases of aging. A comparative, developmental, and ecological approach has the potential to generate novel insights into the regulation of inflammation and how it relates to human health over the life course.

Long-Term Health Benefits of Occupational Licensing: Evidence from Midwifery Laws

During the late 19th and early 20th century, several states mandated midwifery licensing requirements to improve midwives' knowledge, education, and quality. Previous studies point to the health benefits of midwifery quality improvements for maternal and infant health outcomes. This paper exploits the staggered adoption of midwifery laws across states using event-study and difference-in-difference frameworks. We use the universe of death records in the US over the years 1979-2020 and find that exposure to a midwifery licensing law at birth is associated with a 2.5 percent reduction in cumulative mortality rates and an increase of 0.6 months in longevity during adulthood and old age. The effects are concentrated on deaths due to infectious diseases, neoplasm diseases, and suicide mortality. We also show that the impacts are confined among blacks and are slightly larger among males. Additional analyses using alternative data sources suggest small but significant increases in educational attainments, income, measures of socioeconomic status, employment, and measures of height as potential mechanism channels. We provide a discussion on the economic magnitude and policy implication of the results.

Association between infectious exposures in infancy and epigenetic age acceleration in young adulthood in metropolitan Cebu, Philippines

OBJECTIVES

The drivers of human life expectancy gains over the past 200 years are not well-established, with a potential role for historical reductions in infectious disease. We investigate whether infectious exposures in infancy predict biological aging using DNA methylation-based markers that forecast patterns of morbidity and mortality later in life.

METHODS

N = 1450 participants from the Cebu Longitudinal Health and Nutrition Survey-a prospective birth cohort initiated in 1983-provided complete data for the analyses. Mean chronological age was 20.9 years when venous whole blood samples were drawn for DNA extraction and methylation analysis, with subsequent calculation of three epigenetic age markers: Horvath, GrimAge, and DunedinPACE. Unadjusted and adjusted least squares regression models were evaluated to test the hypothesis that infectious exposures in infancy are associated with epigenetic age.

RESULTS

Birth in the dry season, a proxy measure for increased infectious exposure in the first year of life, as well as the number of symptomatic infections in the first year of infancy, predicted lower epigenetic age. Infectious exposures were associated with the distribution of white blood cells in adulthood, which were also associated with measures of epigenetic age.

CONCLUSIONS

We document negative associations between measures of infectious exposure in infancy and DNA methylation-based measures of aging. Additional research, across a wider range of epidemiological settings, is needed to clarify the role of infectious disease in shaping immunophenotypes and trajectories of biological aging and human life expectancy.

Does month of birth influence colorectal cancer prognosis?

PURPOSE

The main aim of this study was to identify a possible association between month of birth of colorectal cancer (CRC) patients and overall survival (OS) or disease-free survival (DFS).

METHODS

This observational study included all consecutive adult patients diagnosed with CRC undergoing oncological surgery from January 2005 to December 2019 with a minimum follow-up of 10 years. The outcome variables were locoregional recurrence, death due to cancer progression, OS and DFS. Non-supervised learning techniques (K-means) were conducted to identify groups of months with similar oncologic outcomes. Finally, OS and DFS were analysed using Kaplan-Meier and Cox regression tests. The model was calibrated with resampling techniques and subsequently a cross-validation was performed.

RESULTS

A total of 2520 patients were included. Three birth month groups with different oncologic outcomes were obtained. Survival analysis showed between-group differences in OS (p < 0.001) and DFS (p = 0.03). The multivariable Cox proportional hazards model identified the clusters obtained as independent prognostic factors for OS (p < 0.001) and DFS (p = 0.031).

CONCLUSION

There is an association between month of birth and oncologic outcomes of CRC. Patients born in the months of January, February, June, July, October and December had better OS and DFS than those born in different months of the year.

Prediction of postoperative hypokalemia in patients with oral cancer undergoing en bloc cancer resection: a retrospective cohort study

BACKGROUND

The factors associated with postoperative hypokalemia in patients with oral cancer remain unclear. We determined the preoperative factors associated with postoperative hypokalemia in patients with oral cancer following en bloc cancer resection and established a nomogram for postoperative hypokalemia prediction.

METHODS

Data from 381 patients with oral cancer who underwent en bloc cancer resection were retrospectively analyzed. Univariate and multivariate analyses were performed to identify the risk factors for postoperative hypokalemia. We used receiver operating characteristic (ROC) curves to quantify the factors' effectiveness. A nomogram was created to show each predictor's relative weight and the likelihood of postoperative hypokalemia development. The multinomial regression model's effectiveness was also evaluated.

RESULTS

Preoperative factors, including sex, preoperative serum potassium level, and preoperative platelet-to-lymphocyte ratio (PLR), were significantly associated with postoperative hypokalemia. Based on the ROC curve, the preoperative serum potassium and PLR cut-off levels were 3.98 mmol/L and 117, respectively. Further multivariate analysis indicated that female sex, preoperative serum potassium level < 3.98 mmol/L, and preoperative PLR ≥ 117 were independently associated with postoperative hypokalemia. We constructed a predictive nomogram with all these factors for the risk of postoperative hypokalemia with good discrimination and internal validation.

CONCLUSIONS

The predictive nomogram for postoperative hypokalemia risk constructed with these factors had good discrimination and internal validation. The developed nomogram will add value to these independent risk factors that can be identified at admission in order to predict postoperative hypokalemia.

Inflammatory proteins are associated with mortality in a middle-aged diverse cohort

BACKGROUND

Recent data indicate a decline in overall longevity in the United States. Even prior to the COVID-19 pandemic, an increase in midlife mortality rates had been reported. Life expectancy disparities have persisted in the United States for racial and ethnic groups and for individuals living at low socioeconomic status. These continued trends in mortality indicate the importance of examining biomarkers of mortality at midlife in at-risk populations. Circulating levels of cytokines and inflammatory markers reflect systemic chronic inflammation, which is a well-known driver of many age-related diseases.

METHODS

In this study, we examined the relationship of nine different inflammatory proteins with mortality in a middle-aged socioeconomically diverse cohort of African-American and White men and women (n = 1122; mean age = 47.8 years).

RESULTS

We found significant differences in inflammatory-related protein serum levels between African-American and White middle-aged adults. E-selectin and fibrinogen were significantly higher in African-American adults. IFN-γ, TNF-α trimer, monocyte chemoattractant protein-1 (MCP-1), soluble receptor for advanced glycation end-products (sRAGE) and P-selectin were significantly higher in White participants compared to African-American participants. Higher levels of E-selectin, MCP-1 and P-selectin were associated with a higher mortality risk. Furthermore, there was a significant interaction between sex and IL-6 with mortality. IL-6 levels were associated with an increased risk of mortality, an association that was significantly greater in women than men. In addition, White participants with high levels of sRAGE had significantly higher survival probability than White participants with low levels of sRAGE, while African-American participants had similar survival probabilities across sRAGE levels.

CONCLUSIONS

These results suggest that circulating inflammatory markers can be utilized as indicators of midlife mortality risk in a socioeconomically diverse cohort of African-American and White individuals.

Investigating the impact of metabolic syndrome traits on telomere length: a Mendelian randomization study

OBJECTIVE

Observational studies have reported bidirectional associations between metabolic syndrome (MetS) traits and short leukocyte telomere length (LTL), a TL marker in somatic tissues and a proposed risk factor for age-related degenerative diseases. However, in Mendelian randomization studies, longer LTL has been paradoxically associated with higher MetS risk. This study investigated the hypothesis that shorter LTL might be a consequence of metabolic dysfunction.

METHODS

This study undertook univariable and multivariable Mendelian randomization. As instrumental variables for MetS traits, all of the genome-wide significant independent signals identified in genome-wide association studies for anthropometric, glycemic, lipid, and blood pressure traits conducted in European individuals were used. Summary-level data for LTL were obtained from a genome-wide association study conducted in the UK Biobank.

RESULTS

Higher BMI was associated with shorter LTL (β = -0.039, 95% CI: -0.058 to -0.020, p = 5 × 10-5 ) equivalent to 1.70 years of age-related LTL change. In contrast, higher low-density lipoprotein cholesterol was associated with longer LTL (β = 0.022, 95% CI: 0.007 to 0.037, p = 0.003) equivalent to 0.96 years of age-related LTL change. Mechanistically, increased low-grade systemic inflammation, as measured by circulating C-reactive protein, and lower circulating linoleic acid levels might link higher BMI to shorter LTL.

CONCLUSIONS

Overweight and obesity might promote the development of aging-related degenerative diseases by accelerating telomere shortening.

Physiological aging in India: The role of the epidemiological transition

We construct a cohort-based frailty index from age-related health deficits to investigate physiological aging in India over the period 1990-2019. During this period, the Indian states underwent at different speeds the epidemiological transition and experienced unprecedented economic growth. We show that the rate of physiological aging remained remarkably stable to the changing environment. Age-related health deficits increased by about 3 percent per year of age with little variation across states, ages, cohorts, and over time. We find that, with advancing epidemiological transition, health deficits for given age declined at the individual level (within states and within cohorts). Across cohorts born between 1900 and 1995, we show that, for given age, health deficits are higher for later-born cohorts until birth years around 1940 and remained trendless afterwards. We propose a selection-based theory of aging during the epidemiological transition that explains these facts.

Epidemiological impacts of post-infection mortality

Infectious diseases may cause some long-term damage to their host, leading to elevated mortality even after recovery. Mortality due to complications from so-called 'long COVID' is a stark illustration of this potential, but the impacts of such post-infection mortality (PIM) on epidemic dynamics are not known. Using an epidemiological model that incorporates PIM, we examine the importance of this effect. We find that in contrast to mortality during infection, PIM can induce epidemic cycling. The effect is due to interference between elevated mortality and reinfection through the previously infected susceptible pool. In particular, robust immunity (via decreased susceptibility to reinfection) reduces the likelihood of cycling; on the other hand, disease-induced mortality can interact with weak PIM to generate periodicity. In the absence of PIM, we prove that the unique endemic equilibrium is stable and therefore our key result is that PIM is an overlooked phenomenon that is likely to be destabilizing. Overall, given potentially widespread effects, our findings highlight the importance of characterizing heterogeneity in susceptibility (via both PIM and robustness of host immunity) for accurate epidemiological predictions. In particular, for diseases without robust immunity, such as SARS-CoV-2, PIM may underlie complex epidemiological dynamics especially in the context of seasonal forcing.

Self-Rated Health and Mortality: Moderation by Purpose in Life

Poor self-rated health consistently predicts reduced longevity, even when objective disease conditions and risk factors are considered. Purpose in life is also a reliable predictor of diverse health outcomes, including greater longevity. Given prior work in which we showed that purpose in life moderated the association between chronic conditions and health-related biological factors, the aim of the current study was to examine the role of purpose in life in moderating the relationship between subjective health and mortality. We also examined potential differences in these associations by race/ethnicity. Data were from two large national longitudinal studies-the Health and Retirement Study (HRS) and the Midlife in the United States (MIDUS) study-with a 12- to 14-year follow-up period for mortality estimates. Results of logistic regression analyses showed that purpose in life and self-rated health were both significantly positively associated with longevity, and that purpose in life significantly moderated the relationship between self-rated health and mortality. Stratified analyses showed similar results across all racial/ethnic groups, with the exception of Black MIDUS participants. These results suggest that greater purpose in life may provide a buffer against the greater probability of mortality associated with poor subjective health.

Racial Discrimination and Multimorbidity Among Older Adults in Colombia: A National Data Analysis

INTRODUCTION

Multimorbidity is a prevalent worldwide problem among older adults. Our objective was to assess the association between life-course racial discrimination and multimorbidity among older adults in Colombia.

METHODS

We used data from the SABE (Salud, Bienestar y Envejecimiento) Colombia Study in 2015 (N = 18,873), a national cross-sectional survey among adults aged 60 years or older. The outcome was multimorbidity, defined as having 2 or more chronic conditions. The main independent variables were 3 racial discrimination measures: 1) everyday racial discrimination (yes or no), 2) childhood racial discrimination score (scored from 0 [never] to 3 [many times]), and 3) situations of racial discrimination in the last 5 years (scored from 0 to 4 as a sum of the number of situations [group activities, public places, inside the family, health centers]). Other variables were sociodemographic characteristics, diseases, economic or health adversity during childhood, and functional status. We used weighted logistic regression analyses to adjust for differences between groups.

RESULTS

Multivariate logistic regression models showed that multimorbidity was significantly associated with experiencing everyday racial discrimination (OR, 2.21; 95% CI, 1.62-3.02), childhood racial discrimination (OR, 1.27; 95% CI, 1.10-1.47), and the number of situations of racial discrimination (OR= 1.56; 95% CI, 1.22-2.00). Multimorbidity was also independently associated with multimorbidity during childhood.

CONCLUSION

Racial discrimination experiences were associated with higher odds of multimorbidity among older adults in Colombia. Strategies to decrease life course experiences of racial discrimination may improve the health of older adults.

Long-Term Transcriptomic Changes and Cardiomyocyte Hyperpolyploidy after Lactose Intolerance in Neonatal Rats

Many cardiovascular diseases originate from growth retardation, inflammation, and malnutrition during early postnatal development. The nature of this phenomenon is not completely understood. Here we aimed to verify the hypothesis that systemic inflammation triggered by neonatal lactose intolerance (NLI) may exert long-term pathologic effects on cardiac developmental programs and cardiomyocyte transcriptome regulation. Using the rat model of NLI triggered by lactase overloading with lactose and the methods of cytophotometry, image analysis, and mRNA-seq, we evaluated cardiomyocyte ploidy, signs of DNA damage, and NLI-associated long-term transcriptomic changes of genes and gene modules that differed qualitatively (i.e., were switched on or switched off) in the experiment vs. the control. Our data indicated that NLI triggers the long-term animal growth retardation, cardiomyocyte hyperpolyploidy, and extensive transcriptomic rearrangements. Many of these rearrangements are known as manifestations of heart pathologies, including DNA and telomere instability, inflammation, fibrosis, and reactivation of fetal gene program. Moreover, bioinformatic analysis identified possible causes of these pathologic traits, including the impaired signaling via thyroid hormone, calcium, and glutathione. We also found transcriptomic manifestations of increased cardiomyocyte polyploidy, such as the induction of gene modules related to open chromatin, e.g., "negative regulation of chromosome organization", "transcription" and "ribosome biogenesis". These findings suggest that ploidy-related epigenetic alterations acquired in the neonatal period permanently rewire gene regulatory networks and alter cardiomyocyte transcriptome. Here we provided first evidence indicating that NLI can be an important trigger of developmental programming of adult cardiovascular disease. The obtained results can help to develop preventive strategies for reducing the NLI-associated adverse effects of inflammation on the developing cardiovascular system.

Do the short die young? Evidence from a large sample of deceased Polish adults

Body height is associated with various socioeconomic and health-related outcomes. Despite numerous studies, the relationship between stature and longevity remains uncertain. This study explores the association between self-reported height and lifespan. Data from 848,860 adults who died between 2004 and 2008 in Poland were collected. After excluding a small proportion of records due to missing data or errors, we examined records for 848,387 individuals (483,281 men, age range: 20–110 years; 365,106 women, age range: 20–112 years). Height was expressed as standardized residual variance derived from linear regression in order to eliminate the variance of year of birth on height. After the elimination of the cohort effect, five height classes were designated using centiles: very short, short, medium, tall and very tall. The differences between sexes and among classes were evaluated with two-way ANOVA and post hoc Tukey’s test. The effect size was assessed using partial eta squared (η2). Pearson’s r coefficients of correlation were calculated. The effect of sex on lifespan was nearly 17 times stronger than the effect of height. No correlation between height and lifespan was found. In conclusion, these findings do not support the hypothesis that taller people have a longevity advantage. We offer tentative explanations for the obtained results.

Childhood health conditions and insomnia among adults in mid-life

Background

Little is known regarding the influence of childhood health broadly and childhood health conditions specifically on insomnia throughout adulthood.

Methods

Health and Retirement Study (HRS) Baby Boomers born 1954-1965 were investigated. We fitted regression models predicting self-reported insomnia based on twenty-three retrospectively reported specific childhood health conditions (e.g., measles) and general childhood health measures and adjusted for demographics, childhood socioeconomic status, and adult socioeconomic status.

Results

Nearly all the measures of childhood health significantly increased insomnia symptoms in adulthood. In a model where all measures were included, we found that respiratory disorders, headaches, stomach problems, and concussions were particularly strong predictors of insomnia.

Conclusions

Our findings extend past work illustrating the "long arm" of childhood conditions for health, showing that specific health conditions in childhood may indelibly imprint insomnia risk.

Social Safety Theory: Conceptual foundation, underlying mechanisms, and future directions

Classic theories of stress and health are largely based on assumptions regarding how different psychosocial stressors influence biological processes that, in turn, affect human health and behavior. Although theoretically rich, this work has yielded little consensus and led to numerous conceptual, measurement, and reproducibility issues. Social Safety Theory aims to address these issues by using the primary goal and regulatory logic of the human brain and immune system as the basis for specifying the social-environmental situations to which these systems should respond most strongly to maximize reproductive success and survival. This analysis gave rise to the integrated, multi-level formulation described herein, which transforms thinking about stress biology and provides a biologically based, evolutionary account for how and why experiences of social safety and social threat are strongly related to health, well-being, aging, and longevity. In doing so, the theory advances a testable framework for investigating the biopsychosocial roots of health disparities as well as how health-relevant biopsychosocial processes crystalize over time and how perceptions of the social environment interact with childhood microbial environment, birth cohort, culture, air pollution, genetics, sleep, diet, personality, and self-harm to affect health. The theory also highlights several interventions for reducing social threat and promoting resilience.

Socioeconomic Positions and Midlife Health Trajectories in a Changing Social Context: Evidence from China, 1991-2006

Cumulative (dis)advantage theory posits that socioeconomic disparities in health may increase with age. This study examines individuals' midlife health trajectories, taking account of how their life courses are embedded within changing social contexts. Using the China Health and Nutrition Survey (1991-2006), it examines the health gap between Chinese rural peasants and urban nonpeasants in three adjacent time periods, during which a rapid process of social change increased the inequalities between rural and urban areas. Findings show that the health gap increases more rapidly in the more recent time periods, with higher levels of inequality, indicating that health inequalities between the two groups are contingent upon the social contexts in which individuals' lives unfold. To better understand the differences observed over these time periods, further analysis will examine the roles of two structural factors: income inequality and differential access to medical care.

Inflammation-related Gene Polymorphisms Associated With Childhood Acute Lymphoblastic Leukemia

BACKGROUND

Acute lymphoblastic leukemia (ALL) is a malignant hematological disease and is often accompanied by a variety of genetic abnormalities. The pathogenesis of inflammation-related single-nucleotide polymorphism (SNP) in children with ALL remains unclear.

OBJECTIVE

This study was to discover the association of the SNP sites of some inflammation-related genes and the susceptibility and treatment response of ALL in children, so as to provide personalized treatment for ALL in children.

PROCEDURE

One hundred sixty-five childhood ALL patients and 175 age-matched healthy participants were recruited in this study. We investigated the involvement of 31 SNPs of the inflammation-related genes in the pathogenesis and treatment response of childhood ALL.

RESULTS

Statistical analysis revealed that rs2280714 in IRF5, rs2297630 in SDF-1, rs4353135 in NLRP3, rs1946518 in interleukin-18 were related to the susceptibility to pediatric ALL. Interleukin-1β rs16944 SNP was correlated with ALL risk stage in children. Rs7633631 in CD226 and rs10818488 in TRAF1 were related to the minimal residual disease (MRD) on day 15 and day 33.

CONCLUSIONS

Certain SNPs of inflammation genes were associated with the susceptibility and treatment response of ALL children. These findings may help in the early detection, diagnostic evaluation, and making individual chemotherapy regimen for ALL children according to the genotype of these sites at the time of initial diagnosis.

The Role of Incarceration as a Risk Factor for Cognitive Impairment

OBJECTIVES

The objective of this study was to understand disparities in cognitive impairment between middle-aged formerly incarcerated (FI) and nonincarcerated individuals.

METHODS

The 1979 National Longitudinal Survey of Youth is a nationally representative longitudinal data set containing information on incarceration, cognitive functioning, and other health conditions. Using a modified version of the Telephone Interview for Cognitive Status (TICS-m), adapted from the Health and Retirement Study, we analyzed the association between incarceration and cognitive impairment, cognitive impairment-not dementia and dementia. Multivariable regression models were estimated, including prior incarceration status and covariates associated with incarceration and cognitive functioning.

RESULTS

FI individuals had lower unadjusted scores on TICS-m (-2.5, p < .001) and had significantly greater unadjusted odds ratios (OR) for scoring in the cognitive impairment (OR = 2.4, p < .001) and dementia (OR = 2.7, p < .001) range. Differences were largely explained by a combination of risk factors associated with incarceration and cognition. Education and premorbid cognition (measured by Armed Forces Qualification Test) separately and completely explained differences in the odds of dementia. Regardless of incarceration status, Blacks and Hispanics had significantly greater odds of cognitive impairment and dementia relative to Whites, holding other factors constant.

DISCUSSION

The association between prior incarceration and cognitive impairment in middle age was largely explained by differences in educational attainment and premorbid cognitive functioning, supporting the cognitive reserve hypothesis. Greater prevalence of cognitive impairment and dementia among the FI could create challenges and should be considered in reentry planning. Structural and institutional factors should be considered when addressing health disparities in Alzheimer's Disease and Related Dementias.

A Unified Model of Cohort Mortality

We propose a dynamic production function of population health and mortality from birth onward. Our parsimonious model provides an excellent fit for the mortality and survival curves for primate and human populations since 1816. The model sheds light on the dynamics behind many phenomena documented in the literature. Simple extensions of the model can reproduce (1) the existence and evolution of mortality gradients across socioeconomic statuses documented in the literature, (2) nonmonotonic dynamic effects of in utero shocks, (3) persistent or scarring effects of wars, and (4) mortality displacement after large temporary shocks, such as extreme weather.

Senescence of the immune defences and reproductive trade-offs in females of the mealworm beetle, Tenebrio molitor

In the theory of ageing, it has been assumed that ageing is associated with a decline in somatic defences, including the immune system, as a consequence of a trade-off with reproduction. While overall immunity suffers from age-related deterioration (immune senescence), the different components of the immune response appear to age differently. It is also likely that investment among the many arms of the immune system and reproduction with age is finely adjusted to the organisms' reproductive strategy. We investigated this possibility in females of Tenebrio molitor, a species of long-lived insect with reproductive strategies similar to those of long-lived mammals. We specifically tested the effects of immunological challenges imposed early or late in adult life on immune pathway activation as well as fertility early and late in life. We found complex patterns of changes in immune defences with age and age-specific immune challenges with contrasted relationships with female reproduction. While cellular and enzymatic defences showed signs of ageing, they did not trade-off with reproduction. By contrast, the induced antibacterial immune response was found to be unaffected by age and to be highly connected to female fecundity. These findings suggest that these immunological pathways have different functions with regard to female ageing in this insect species.

Maternal nutritional status and offspring childlessness: Evidence from the late-nineteenth to early-twentieth centuries in a group of Italian populations

The role of maternal nutrition in affecting offspring fertility, through alteration of foetal programming, has been demonstrated in animal-based experiments. However, results from human populations appear inconsistent and sometimes contradictory, likely because they have been based on single famine events. In this paper, we adopt a different approach. We combine official annual time series of daily nutrient availability with a sample of women's reproductive histories from the 1961 Italian Census to investigate the role of maternal nutritional status in pregnancy on offspring childlessness. The analysis therefore covers cohorts of females born between 1861 and 1939. Our results show a negative association between calorie availability in pregnancy and the odds of offspring childlessness, whereas no association is found between protein availability and offspring childlessness. The consequences of poor calorie intake were aggravated during the summer, likely due to the participation of pregnant women in physically demanding work.

Lessons from Sicilian Centenarians for Anti-Ageing Medicine. The Oxi-Inflammatory Status

Population ageing is a great achievement of humanity, but it also represents a challenge that the Western world is currently facing, as ageing is associated with increased susceptibility to age-related inflammatory diseases. Therefore, it is necessary to fully understand the mechanisms of healthy ageing to prevent the harmful aspects of ageing. The study of long living individuals (LLIs) is a great model for trying to achieve this goal. Accordingly, the oxy-inflammatory status of Sicilian LLIs was reviewed in the present paper. Based on the reported data, anti-inflammatory and anti-oxidative stress strategies have been discussed, useful for delaying or avoiding the onset of age-related diseases, thus favouring a healthy ageing process.

Sensitisation to Pollen Allergens in Children and Adolescents of Different Ancestry Born and Living in the Same Area

Background

Allergy can start at early ages, with genetic and environmental factors contributing to its development.

Aim

The study aimed to describe the pattern of sensitisation and allergy in children and adolescents of Spanish versus Moroccan ancestry but born in the same rural area of Spain.

Methods

Participants were children and adolescents (3–19 years) of Spanish or Moroccan descent, born in Blanca, Murcia (Spain). A detailed questionnaire was completed, and skin prick tests were performed to assess reactions to the most prevalent pollen allergens (O. europaea, P. pratense, S. kali, C. arizonica, P. acerifolia, A. vulgaris and P. judaica) plus molecular components Ole e 1 and Ole e 7. The association with ancestry was verified by studying participants’ parents.

Results

The study included 693 participants: 48% were aged 3–9 years and 52%, 10–19 years; 80% were of Spanish descent and 20% of Moroccan descent. Sensitisation to Olea europaea, Phleum pratense, Salsola kali and Cupressus arizonica were slightly higher in the Spanish group. The only significant differences were observed in sensitisation to Ole e 1 (p=0.02). Rhinitis, conjunctivitis, and rhinitis plus asthma were significantly higher in the Spanish group (p=0.03, p=0.02, p=0.007, respectively). The sensitisation pattern differed between Spanish and Moroccan parents, and between Moroccan parents and their children, but not between Spanish parents and their children.

Conclusion

Both environment and ancestry may influence sensitisation and symptoms. Although the environment seems to have a stronger influence, other factors may contribute to the differences in prevalence and in the clinical entities in people of Spanish versus Moroccan descent.

Scarring and selection effects on children surviving elevated rates of postneonatal mortality in sub-Saharan Africa

Infants in sub-Saharan Africa face adversity: Infections and undernutrition are major causes of infant deaths and can cause physiological damage with long-lasting adverse scarring effects on the human development of the survivors, for example, in terms of health and education. However, selective mortality of more vulnerable children at very high levels of adversity in early life can leave the surviving population to appear on average healthier. This paper estimated the nonlinear effects of postneonatal mortality rate—a proxy for adversity, particularly infections and undernutrition—in a 50 km radius, occurring over the period of infancy, on the subsequent height-for-age and school attendance of the surviving children. The results indicated that an adverse environment in infancy negatively affected height-for-age at age 1–4 years: At relatively low levels of adversity (at the 10th percentile of postneonatal mortality rate), an additional postneonatal death per 100 person-years decreased height-for-age of the survivors by almost 2% of the mean deficit in height (relative to a common growth standard) when comparing siblings born into different levels of adversity. At high levels of adversity, no effect was found for height-for-age while a small positive association was observed for school attendance at age 7–16 years. The results indicated that selective mortality may have canceled out (or even dominated in the case of school attendance) observable scarring effects following high levels of postneonatal mortality rate in sub-Saharan Africa.

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Adversity in early life negatively affects human development in sub-Saharan Africa.

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The postneonatal mortality rate over infancy was used as a proxy for adversity.

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Elevated adversity in infancy negatively affected height-for-age at age 1–4 years.

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At high adversity, selective mortality may cancel out observable scarring effects.

Life Course Socioeconomic Status and Healthy Longevity in China

In 2020, China's population aged 60 or older exceeded 264 million, representing 25% of the global population in that age-group. Older adults in China experienced periods of dramatic political and social unrest in early life, as well as economic transformations leading to drastic improvements in living standards during adulthood and older age. However, the implications of life course socioeconomic status (SES) trajectories for healthy longevity in later life have not been systematically studied in China. We utilize data from the China Health and Retirement Longitudinal Study (CHARLS) to comprehensively investigate how early-life conditions and adult SES combine to influence healthy longevity in later life. We find that both childhood and adulthood SES are associated with late-life health. The largest disparities in life expectancy (LE) and disability-free LE are found between those with persistently low SES throughout life and those with consistently high SES. At age 45, the gap in total LE between the most advantaged and least advantaged groups is six years for men and five years for women. Despite China's major policy changes prioritizing equity in income and health care in recent decades, our findings suggest that dramatic health inequalities among older adults remain. Our findings extend the literature on the effect of socioeconomic patterns across the life course on gradients in later-life health and highlight continuing disparities in healthy longevity among older adults in China.

Population-level impact of adverse early life conditions on adult healthy life expectancy in low- and middle-income countries

Evidence from theories of Developmental Origins of Health and Disease (DOHaD) suggests that experiencing adverse early life conditions subsequently leads to detrimental adult health outcomes. The bulk of empirical DOHaD literature does not consider the nature and magnitude of the impact of adverse early life conditions at the population level. In particular, it ignores the distortion of age and cohort patterns of adult health and mortality and the increased load of chronic illness and disability that ensues. In this paper, we use a microsimulation model combined with empirical estimates of incidence and prevalence of obesity, type 2 diabetes, and associated disability in low- and middle-income countries to assess the magnitude of delayed effects on adult healthy life expectancy and on compression (or expansion) of morbidity at older ages. The main goal is to determine if, in what ways, and to what extent delayed effects due to early conditions can influence cohorts' chronic illness and disability profiles.

Population-level impact of adverse early life conditions on adult healthy life expectancy in low- and middle-income countries

Evidence from theories of Developmental Origins of Health and Disease (DOHaD) suggests that experiencing adverse early life conditions subsequently leads to detrimental adult health outcomes. The bulk of empirical DOHaD literature does not consider the nature and magnitude of the impact of adverse early life conditions at the population level. In particular, it ignores the distortion of age and cohort patterns of adult health and mortality and the increased load of chronic illness and disability that ensues. In this paper, we use a microsimulation model combined with empirical estimates of incidence and prevalence of obesity, type 2 diabetes, and associated disability in low- and middle-income countries to assess the magnitude of delayed effects on adult healthy life expectancy and on compression (or expansion) of morbidity at older ages. The main goal is to determine if, in what ways, and to what extent delayed effects due to early conditions can influence cohorts' chronic illness and disability profiles.

Age, Period, and Cohort Effects in Alcohol Use in the United States in the 20th and 21st Centuries: Implications for the Coming Decades

This article is part of a Festschrift commemorating the 50th anniversary of the National Institute on Alcohol Abuse and Alcoholism (NIAAA). Established in 1970, first as part of the National Institute of Mental Health and later as an independent institute of the National Institutes of Health, NIAAA today is the world's largest funding agency for alcohol research. In addition to its own intramural research program, NIAAA supports the entire spectrum of innovative basic, translational, and clinical research to advance the diagnosis, prevention, and treatment of alcohol use disorder and alcohol-related problems. To celebrate the anniversary, NIAAA hosted a 2-day symposium, "Alcohol Across the Lifespan: 50 Years of Evidence-Based Diagnosis, Prevention, and Treatment Research," devoted to key topics within the field of alcohol research. This article is based on Dr. Keyes' presentation at the event. NIAAA Director George F. Koob, Ph.D., serves as editor of the Festschrift.

What have we learned about mortality patterns over the past 25 years?

In this paper, I examine progress in the field of mortality over the past 25 years. I argue that we have been most successful in taking advantage of an increasingly data-rich environment to improve aggregate mortality models and test pre-existing theories. Less progress has been made in relating our estimates of mortality risk at the individual level to broader mortality patterns at the population level while appropriately accounting for contextual differences and compositional change. Overall, I find that the field of mortality continues to be highly visible in demographic journals, including Population Studies. However much of what is published today in field journals could just as easily appear in neighbouring disciplinary journals, as disciplinary boundaries are shrinking.

Are Recent Cohorts Getting Worse? Trends in US Adult Physiological Status, Mental Health, and Health Behaviors Across a Century of Birth Cohorts

Morbidity and mortality have been increasing among middle-aged and young-old Americans since the turn of the century. We investigated whether these unfavorable trends extend to younger cohorts and their underlying physiological, psychological, and behavioral mechanisms. Applying generalized linear mixed-effects models to data from 62,833 adults from the National Health and Nutrition Examination Surveys (1988-2016) and 625,221 adults from the National Health Interview Surveys (1997-2018), we found that for all sex and racial groups, physiological dysregulation has increased continuously from Baby Boomers through late-Generation X and Generation Y. The magnitude of the increase was higher for White men than for other groups, while Black men had a steepest increase in low urinary albumin (a marker of chronic inflammation). In addition, Whites underwent distinctive increases in anxiety, depression, and heavy drinking, and they had a higher level than Blacks and Hispanics of smoking and drug use in recent cohorts. Smoking is not responsible for the increasing physiological dysregulation across cohorts. The obesity epidemic contributes to the increase in metabolic syndrome but not in low urinary albumin. The worsening physiological and mental health profiles among younger generations imply a challenging morbidity and mortality prospect for the United States, one that might be particularly inauspicious for Whites.

Early-Life War Exposure and Later-Life Frailty Among Older Adults in Vietnam: Does War Hasten Aging?

OBJECTIVES

To assess the nature and degree of association between exposure to potentially-traumatic wartime experiences in early life, such as living in a heavily bombed region or witnessing death first-hand, and later-life frailty.

METHODS

The Vietnam Health and Aging Study included war survivors in Vietnam, 60+, who completed a survey and health exam between May and August 2018. Latent Class Analysis is used to construct classes exposed to similar numbers and types of wartime experiences. Frailty is measured using a deficit accumulation approach that proxies biological aging. Fractional logit regression associates latent classes with frailty scores. Coefficients are used to calculate predicted frailty scores and expected age at which specific levels of frailty are reached across wartime exposure classes.

RESULTS

LCA yields nine unique wartime exposure classes, ranging from extreme exposure to non-exposed. Higher frailty is found among those with more heavy/severe exposures with a combination of certain types of experiences, including intense bombing, witnessing death first-hand, having experienced sleep disruptions during wartime, and having feared for one's life during war. The difference in frailty-associated aging between the most and least affected individuals is more than 18 years.

DISCUSSION

War trauma hastens aging and warrants greater attention toward long-term implications of war on health among vast post-conflict populations across the globe.

Telomere length and metabolic syndrome traits: A Mendelian randomisation study

Observational studies have revealed associations between short leucocyte telomere length (LTL), a TL marker in somatic tissues and multiple Metabolic Syndrome (MetS) traits. Animal studies have supported these findings by showing that increased telomere attrition leads to adipose tissue dysfunction and insulin resistance. We investigated the associations between genetically instrumented LTL and MetS traits using Mendelian Randomisation (MR). Fifty-two independent variants identified at FDR<0.05 from a genome-wide association study (GWAS) including 78,592 Europeans and collectively accounting for 2.93% of LTL variance were selected as genetic instruments for LTL. Summary-level data for MetS traits and for the MetS as a binary phenotype were obtained from the largest publicly available GWAS and two-sample MR analyses were used to estimate the associations of LTL with these traits. The combined effect of the genetic instruments was modelled using inverse variance weighted regression and sensitivity analyses with MR-Egger, weighted-median and MR-PRESSO were performed to test for and correct horizonal pleiotropy. Genetically instrumented longer LTL was associated with higher waist-to-hip ratio adjusted for body mass index (β = 0.045 SD, SE = 0.018, p = 0.01), raised systolic (β = 1.529 mmHg, SE = 0.332, p = 4x10^-6 ) and diastolic (β = 0.633 mmHg, SE = 0.222, p = 0.004) blood pressure, and increased MetS risk (OR = 1.133, 95% CI 1.057-1.215). Consistent results were obtained in sensitivity analyses, which provided no evidence of unbalanced horizontal pleiotropy. Telomere shortening might not be a major driver of cellular senescence and dysfunction in human adipose tissue. Future experimental studies should examine the mechanistic bases for the links between longer LTL and increased upper-body fat distribution and raised blood pressure.

Activation of innate immunity during development induces unresolved dysbiotic inflammatory gut and shortens lifespan

Early-life inflammatory response is associated with risks of age-related pathologies. How transient immune signalling activity during animal development influences life-long fitness is not well understood. Using Drosophila as a model, we find that activation of innate immune pathway IMD signalling in the developing larvae increases adult starvation resistance, decreases food intake, and shortens organismal lifespan. Interestingly, lifespan is shortened by the IMD activation in the larval gut and fat body, while starvation resistance and food intake are altered by that in neurons. The adult flies developed with IMD activation show sustained IMD activity in the gut, despite complete tissue renewal during metamorphosis. The larval IMD activation increases an immuno-stimulative bacterial species Gluconobacter sp. in the gut microbiome, and this dysbiosis is persistent to adulthood. Removing gut microbiota by antibiotics in adult mitigates intestinal immune activation and rescues the shortened lifespan. This study demonstrates that early-life immune activation triggers long-term physiological changes as highlighted as an irreversible gut microbiota alteration, prolonged inflammatory intestine, and concomitant shortening of the organismal lifespan.

Conceptual and analytical overlap between allostatic load and systemic biological aging measures: Analyses from the National Survey of Midlife Development in the United States

BACKGROUND

Indices quantifying allostatic load (AL) and biological aging (BA) have independently received widespread use in epidemiological literature. However, little attention has been paid to their conceptual and quantitative overlap. By reviewing literature utilizing measures of AL and BA, and conducting comparative analysis, we highlight similarities and differences in biological markers employed and approach toward scale construction. Further, we outline opportunities where both types of indices might be improved by adopting methodological features of the other.

METHODS

Using data from the National Survey of Midlife Development in the United States (N=2,055, age=26-86), we constructed three AL indices: one common literature standard, and two alternative formulations informed by previous work with measures of BA. The performance of AL indices was juxtaposed against two commonly employed BA indices: Klemera-Doubal Method Biological Age and Homeostatic Dysregulation.

RESULTS

All indices correlated with chronological age. Participants with higher AL and older BA performed worse on tests of physical and subjective functioning. Further, participants with increased life-course risk exposure exhibited higher AL and BA. Notably, alternative AL formulations tended to exhibit effect-sizes equivalent to or larger than those observed for BA measures, and displayed superior mortality prediction.

CONCLUSIONS

In addition to their conceptual similarity, AL and BA indices also exhibit significant analytical similarity. Further, BA measures are robust to construction using a panel of biomarkers not observed in previous iterations, including carotenoids indexing antioxidant capacity. In turn, AL indices could benefit by adopting the methodological rigor formalized within BA composites, such as applying biomarker down-selection criteria.

Life-course trajectories of body mass index from adolescence to old age: Racial and educational disparities

No research exists on how body mass index (BMI) changes with age over the full life span and social disparities therein. This study aims to fill the gap using an innovative life-course research design and analytic methods to model BMI trajectories from early adolescence to old age across 20th-century birth cohorts and test sociodemographic variation in such trajectories. We conducted the pooled integrative data analysis (IDA) to combine data from four national population-based NIH longitudinal cohort studies that collectively cover multiple stages of the life course (Add Health, MIDUS, ACL, and HRS) and estimate mixed-effects models of age trajectories of BMI for men and women. We examined associations of BMI trajectories with birth cohort, race/ethnicity, parental education, and adult educational attainment. We found higher mean levels of and larger increases in BMI with age across more recent birth cohorts as compared with earlier-born cohorts. Black and Hispanic excesses in BMI compared with Whites were present early in life and persisted at all ages, and, in the case of Black-White disparities, were of larger magnitude for more recent cohorts. Higher parental and adulthood educational attainment were associated with lower levels of BMI at all ages. Women with college-educated parents also experienced less cohort increase in mean BMI. Both race and education disparities in BMI trajectories were larger for women compared with men.

Obstructive Sleep Apnea-hypopnea Syndrome as a Novel Potential Risk for Aging

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is a common sleep disorder, negatively influencing individuals' quality of life and socioeconomic burden. In recent years, OSAHS has been reported in not only constituting an aging-associated disease, but also in accelerating and/or potentiating aging mechanisms. However, the negative impacts of OSAHS on aging are underestimated because of low level of public awareness about this disease and high rates of undiagnosed cases, which are more critical in developing countries or economically disadvantaged regions. Hence, reviewing previously reported observations may assist scholars to better indicate that OSAHS is likely a novel potential risk for aging. Further understanding of the pathophysiological mechanism of OSAHS and its role in procession of aging may markedly highlight the importance of this common sleep disorder.

Exosomes and Exosomal MicroRNAs in Age-Associated Stroke

Aging has been considered to be the most important non-modifiable risk factor for stroke and death. Changes in circulation factors in the systemic environment, cellular senescence and artery hypertension during human ageing have been investigated. Exosomes are nanosize membrane vesicles that can regulate target cell functions via delivering their carried bioactive molecules (e.g. protein, mRNA, and microRNAs). In the central nervous system, exosomes and exosomal microRNAs play a critical role in regulating neurovascular function, and are implicated in the initiation and progression of stroke. MicroRNAs are small non-coding RNAs that have been reported to play critical roles in various biological processes. Recently, evidence has shown that microRNAs are packaged into exosomes and can be secreted into the systemic and tissue environment. Circulating microRNAs participate in cellular senescence and contribute to age-associated stroke. Here, we provide an overview of current knowledge on exosomes and their carried microRNAs in the regulation of cellular and organismal ageing processes, demonstrating the potential role of exosomes and their carried microRNAs in age-associated stroke.

Metformin: A Novel Weapon Against Inflammation

It has become widely accepted that inflammation is a driving force behind a variety of chronic diseases, such as cardiovascular disease, diabetes, kidney disease, cancer, neurodegenerative disorders, etc. However, the existing nonsteroidal anti-inflammatory drugs show a limited utility in clinical patients. Therefore, the novel agents with different inflammation-inhibitory mechanisms are worth pursuing. Metformin, a synthetic derivative of guanidine, has a history of more than 50 years of clinical experience in treating patients with type 2 diabetes. Intense research efforts have been dedicated to proving metformin’s inflammation-inhibitory effects in cells, animal models, patient records, and randomized clinical trials. The emerging evidence also indicates its therapeutic potential in clinical domains other than type 2 diabetes. Herein, this article appraises current pre-clinical and clinical findings, emphasizing metformin’s anti-inflammatory properties under individual pathophysiological scenarios. In summary, the anti-inflammatory effects of metformin are evident in pre-clinical models. By comparison, there are still clinical perplexities to be addressed in repurposing metformin to inflammation-driven chronic diseases. Future randomized controlled trials, incorporating better stratification/targeting, would establish metformin’s utility in this clinical setting.

Matriliny reverses gender disparities in inflammation and hypertension among the Mosuo of China

Women experience higher morbidity than men, despite living longer. This is often attributed to biological differences between the sexes; however, the majority of societies in which these disparities are observed exhibit gender norms that favor men. We tested the hypothesis that female-biased gender norms ameliorate gender disparities in health by comparing gender differences in inflammation and hypertension among the matrilineal and patrilineal Mosuo of China. Widely reported gender disparities in health were reversed among matrilineal Mosuo compared with patrilineal Mosuo, due to substantial improvements in women's health, with no concomitant detrimental effects on men. These findings offer evidence that gender norms limiting women's autonomy and biasing inheritance toward men adversely affect the health of women, increasing women's risk for chronic diseases with tremendous global health impact.

Famine-related mortality in early life and accelerated life histories in nineteenth-century Belgium

Density-dependent and extrinsic mortality are predicted to accelerate reproductive maturation. The first 5 years of life is a proposed sensitive period for life-history regulation. This study examines the ways in which local mortality during this sensitive period was related to subsequent marriage timing in nineteenth-century Belgium (n women = 11 892; n men = 14 140). Local mortality during the sensitive period was inversely associated with age at first marriage for men and women controlling for literacy, occupational status, population growth and migration. Cox regression indicated decreased time to marriage for women (HR = 1.661, 95% CI: 1.542-1.789) and men (HR = 1.327, 95% CI: 1.238-1.422) from high mortality municipalities. Rising population growth rates were associated with earlier marriage for men and women. Migration in general was associated with later marriage for men and women. Consistent with life-history predictions, harsh ecological conditions during early life such as famine coincided with earlier marriage.

Non-esterified fatty acids and telomere length in older adults: The Cardiovascular Health Study

Background

Telomeres shorten as organisms age, placing limits on cell proliferation and serving as a marker of biological aging. Non-esterified fatty acids (NEFAs) are a key mediator of age-related metabolic abnormalities. We aimed to determine if NEFAs are associated with telomere length in community-living older adults.

Material and methods

We cross-sectionally studied 1648 participants of the Cardiovascular Health Study (CHS) who underwent concomitant telomere length measurement from a sample of 4715 participants who underwent measurement of circulating total fasting NEFAs in stored specimens from their 1992-3 clinic visit. We used linear regression and inverse probability weighting to model telomere length as a function of NEFAs with adjustment for age, gender, race, clinic, BMI, marital status, smoking status, alcohol intake, diabetes status, years of education, hypertension status, prevalent cardiovascular disease, C-reactive protein, total adiponectin, albumin, fetuin-A, fasting insulin, eGFR, total cholesterol, HDL-cholesterol, triglycerides, and general health status.

Results

Higher NEFAs were significantly associated with shorter telomere length, after adjusting for age, gender, race, and clinic site (β = −0.034; SE = 0.015; P = 0.02). Estimates remained similar in fully adjusted models where each SD of NEFA increment was associated with 0.042 kilobase (kb) pairs shorter telomere length (standard error = 0.016; P = 0.007); for comparison the coefficient for a single year of age in the same model was −0.017. These results were similar in strata of sex, and waist circumference although they tended to be strongest among participants in the youngest tertile of age (β = -0.079; SE = 0.029; P = 0.01).

Conclusions

In this population-based cohort of community-living elders, we observed a significant inverse association between NEFAs and telomere length. If confirmed, NEFAs may represent a promising target for interventions to slow biological aging.

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Shorter telomere lengths have been linked to accelerated aging and disease.

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Oxidative stress and inflammation drives telomere length shortening.

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Non-esterified fatty acids induce oxidative stress and inflammation.

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Higher levels of non-esterified fatty acids were associated with shorter telomeres.

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Non-esterified fatty acids may be an intervention target to slow biological aging.