Association of Parental Socioeconomic Status and Newborn Telomere Length

Describing Biological Vulnerability in Small, Vulnerable Newborns in Urban Burkina Faso (DenBalo): Gut Microbiota, Immune System, and Breastmilk Assembly

Background: Small vulnerable newborns (SVNs), including those born preterm, small for gestational age, or with low birth weight, are at higher risk of neonatal mortality and long-term health complications. Early exposure to maternal vaginal microbiota and breastfeeding plays a critical role in the development of the neonatal microbiota and immune system, especially in low-resource settings like Burkina Faso, where neonatal mortality rates remain high. Objectives: The DenBalo study aims to investigate the role of maternal and neonatal factors, such as vaginal and gut microbiota, immune development, and early nutrition, in shaping health outcomes in SVNs and healthy infants. Methods: This prospective cohort observational study will recruit 141 mother-infant pairs (70 SVNs and 71 healthy controls) from four health centers in Bobo-Dioulasso, Burkina Faso. The mother-infant pairs will be followed for six months with anthropometric measurements and biospecimen collections, including blood, breast milk, saliva, stool, vaginal swabs, and placental biopsies. Multi-omics approaches, encompassing metagenomics, metabolomics, proteomics, and immune profiling, will be used to assess vaginal and gut microbiota composition and functionality, immune cell maturation, and cytokine levels at critical developmental stages. Conclusions: This study will generate comprehensive data on how microbiota, metabolomic, and proteomic profiles, along with immune system development, differ between SVNs and healthy infants. These findings will guide targeted interventions to improve neonatal health outcomes and reduce mortality, particularly in vulnerable populations.

Association Between Adverse Early Life Factors and Telomere Length in Middle and Late Life

Background and Objectives

Telomere length (TL) has been acknowledged as biomarker of biological aging. Numerous investigations have examined associations between individual early life factors and leukocyte TL; however, the findings were far from consistent.

Research Design and Methods

We evaluated the relationship between individual and combined early life factors and leukocytes TL in middle and late life using data from the UK Biobank. The early life factors (eg, maternal smoking, breastfeeding, birth weight, and comparative body size and height to peers at age 10) were measured. The regression coefficients (β) and 95% confidence interval (CI) were applied to assess the link of the early life factors and TL in adulthood. Flexible parametric survival models incorporated age to calculate the relationship between early life factors and life expectancy.

Results

Exposure to maternal smoking, lack of breastfeeding, low birth weight, and shorter height compared to peers at age 10 were identified to be associated with shorter TL in middle and older age according to the large population-based study with 197 504 participants. Individuals who experienced more than 3 adverse early life factors had the shortest TL in middle and late life (β = -0.053; 95% CI = -0.069 to -0.038; p < .0001), as well as an average of 0.54 years of life loss at the age of 45 and 0.49 years of life loss at the age of 60, compared to those who were not exposed to any early life risk factors.

Discussion and Implications

Early life factors including maternal smoking, non-breastfed, low birth weight, and shorter height compared to peers at age 10 were associated with shorter TL in later life. In addition, an increased number of the aforementioned factors was associated with a greater likelihood of shorter TL in adulthood, as well as a reduced life expectancy.

Exploring the impact of lifestyle and environmental exposures on appetite hormone levels in children and adolescents: An observational study

BACKGROUND

Appetite hormones are considered a promising target in fighting obesity as impaired appetite hormone levels have already been associated with obesity. However, further insights in the drivers of appetite hormone levels are needed.

OBJECTIVES

In this study, we investigated the associations of fasting appetite hormone levels with lifestyle and environmental exposures in children and adolescents.

METHODS

A total of 534 fasting blood samples were collected from children and adolescents (4-16y,50% boys) and appetite hormone levels (glucagon-like peptide-1 (GLP-1), peptide YY (PYY), pancreatic polypeptide (PP), leptin and ghrelin) were measured. Exposures included dietary quality (fiber-rich food intake, sugar propensity, fat propensity), psychosocial stress (happiness, negative emotions, negative life events and emotional problems), sleep duration, physical activity and environmental quality (long term black carbon (BC), particulate matter <2.5 μM (PM2.5), nitrogen dioxide (NO2) exposure, and green space in a 100 m and 2000 m radius around the residence). A multi-exposure score was calculated to combine all the exposures at study in one measure. Associations of individual exposures and multi-exposure score with appetite hormone levels were evaluated using linear mixed regression models adjusting for sex, age, socioeconomic status, waist-to-height ratio and multiple testing.

RESULTS

GLP-1 was associated with air pollution exposure (NO2 β* = -0.13, BC β* = -0.15, PM2.5 β* = -0.16, all p < 0.001). Leptin was associated with green space in a 100 m radius around the residence (β* = -0.11; p = 0.002). Ghrelin was associated with negative emotions (active ghrelin β* = -0.16; p = 0.04, total ghrelin β* = -0.23; p = 0.0051) and happiness (active ghrelin β* = 0.25; p < 0.001, total ghrelin β* = 0.26; p < 0.001). Furthermore, total ghrelin levels were associated with the multi-exposure score, reflecting unhealthy exposures and lifestyle (β* = -0.22; p = 0.036).

DISCUSSION

Our findings provide new insights into the associations of exposures with appetite hormone levels, which are of high interest for preventive obesity research. Further research is crucial to reveal the underlying mechanisms of the observed associations.

Robust evidence supports a causal link between higher birthweight and longer telomere length: a mendelian randomization study

Background

Observational studies have suggested a potential relationship between birthweight and telomere length. However, the causal link between these two parameters remains undefined. In this study, we use Mendelian Randomization (MR). This method employs genetic variants as instrumental variables, to explore the existence of causal associations and elucidate the causal relationship between birth weight and telomere length.

Methods

We used 35 single nucleotide polymorphisms (SNPs) as instrumental variables for birth weight. These SNPs were identified from a meta-analysis involving 153,781 individuals. Furthermore, we obtained summary statistics for telomere length from a study conducted on 472,174 United Kingdom Biobank participants. To evaluate the causal estimates, we applied the random effect inverse variance weighted method (IVW) and several other MR methods, such as MR-Egger, weighted median, and MR-PRESSO, to verify the reliability of our findings.

Results

Our analysis supports a significant causal relationship between genetically predicted birth weight and telomer3e length. The inverse variance weighted analysis results for birth weight (Beta = 0.048; 95%CI = 0.023 to 0.073; p < 0.001) corroborate this association.

Conclusion

Our study provides robust evidence supporting a causal link between higher birth weight and longer telomere length.

Prenatal exposure to air pollution and BWGA Z-score: Modifying effects of placenta leukocyte telomere length and infant sex

BACKGROUND

Air pollutants, such as fine particulate matter (PM2.5), nitrogen dioxide (NO2), and ozone (O3), have been associated with adverse birth outcomes, including low birth weight, often exhibiting sex-specific effects. However, the modifying effect of placental telomere length (TL), reflecting cumulative lifetime oxidative stress in mothers, remains unexplored.

METHOD

Using data from a Northeastern U.S. birth cohort (n = 306), we employed linear regression and weighted quantile sum models to assess trimester-average air pollution exposures and birth weight for gestational age (BWGA) z-scores. Placental TL, categorized by median split, was considered as an effect modifier. Interactions among air pollutants, placental TL, infant sex, and BWGA z-score were evaluated.

RESULTS

Without placental TL as a modifier, only 1st trimester O3 was significantly associated with BWGA z-scores (coefficient: 0.33, 95% CI: 0.03, 0.63). In models considering TL interactions, a significant modifying effect was observed between 3rd trimester NO2 and BWGA z-scores (interaction p-value = 0.02). Specifically, a one interquartile range (1-IQR) increase in 3rd trimester NO2 was linked to a 0.28 (95% CI: 0.06, 0.52) change in BWGA z-score among shorter placental TL group, with no significant association among longer TL group. Among male infants, there were significant associations between 3rd trimester PM2.5 exposure and BWGA z-scores in the longer TL group (coefficient: -0.34, 95% CI: -0.61, -0.02), and between 1st trimester O3 exposure and BWGA z-scores among males in the shorter TL group (coefficient: 0.59, 95% CI: 0.06, 1.08). For females, only a negative association in 2nd trimester mixture model was observed within the longer TL group (coefficient: -0.10, 95% CI: -0.21, -0.01).

CONCLUSION

These findings highlight the need to consider the complex interactions among prenatal air pollutant exposures, placental TL, and fetal sex to better elucidate those at greatest risk for adverse birth outcomes.

Identification of polymorphic alleles in TERC and TERT gene reprogramming the telomeres of newborn and legacy with parental health

Telomere and telomerase genes (TERC and TERT) highlighted many novel genetic polymorphisms related to common diseases. This study explored the polymorphic alleles of TERC and TERT gene in parents-newborn (triad) and its association with telomere length (TL) and parental diseases (mother: Gestational Diabetes Mellitus (GDM), Preeclampsia, fathers: Diabetes, Hypertension). In this cross-sectional study, the blood samples (n = 612) were collected from parents-newborn triad (204 each) for TL (T/S ratio) quantification by using qPCR, and gene (TERC and TERT) polymorphism was detected by Sanger sequencing. The correlation analysis was used to find an association between paternal TL (T/S ratio) and newborn TL. The multivariate linear regression was applied to determine the effect of parents genes and diseases on newborn TL. A positive association (r = 0.42,0.39) (p < 0.0001) among parents and newborn TL was observed. In the diseased group, both TERC (rs10936599) and TERT (rs2736100) genes had a high frequency of allele C in newborns (OR = 0.94, P = 0.90, OR = 4.24, P = 0.012). However, among parents, TERT gene [Mother CC (B = 0.575; P = 0.196), Father CC (B = -0.739; P = 0.071)] was found significant contributing factor for Newborn TL. Diseased parents with T/T and A/C genotypes had longer newborn TL (2.82 ± 2.43, p < 0.022; 1.80 ± 1.20, p < 0.00) than the C/C genotype. Therefore, the study, confirmed that major allele C of TERC and TERT genes is associated with smaller TL in diseased parents-newborns of the targeted population.

Food Insecurity, telomere length and the potential modifying effects of social support in National Health and Nutrition Examination Survey

OBJECTIVE

Telomere length (TL) is a posited pathway through which chronic stress results in biological dysregulation and subsequent adverse health outcomes. Food insecurity is associated with shorter TL. Social support, which is defined by the size and function of an individual's social network, is associated with better health outcomes. The present study assesses whether social support modifies the relationship between food security and TL.

DESIGN

Cross-sectional study design. Linear regression was used to assess the association between food insecurity and TL, stratified by social support level. A multiplicative interacted model was used to formally test modification.

SETTING

Data come from the National Health and Nutrition Examination Survey 1999-2000 and 2001-2002 waves.

PARTICIPANTS

Adults aged 60 years and older who have measurements for TL.

RESULTS

Our sample comprised 2674 participants, and 63·5 % of the total sample had low social support, with 13·3 % being food insecure. In fully adjusted models, food insecurity was negatively though modestly associated (P = 0·13) with TL. Associations between food insecurity and TL were significantly modified by social support (interaction P = 0·026), whereby food insecurity had a stronger effect among individuals with high social support (coefficient = -0·099 (95 % CI: -0·161, -0·038)) compared to low social support (coefficient = -0·001, (95 % CI: -0·033, 0·032)).

CONCLUSION

Food insecurity is modestly associated with shorter TL. Contrary to our hypothesis, food insecurity had more deleterious effects on TL among participants with high social support than low social support. Results may indicate that the food insecure population is a higher needs population, and increased social support reflects these needs rather than providing protective effects.

Investigating the association of prenatal psychological adversities with mother and child telomere length and neurodevelopment

BACKGROUND

Exposure to prenatal maternal psychological adversities can negatively affect the offspring's developing brain. Shortened telomere length (TL) has been implicated as a mechanism for the transgenerational effects of maternal psychological adversities on offspring. This study aimed to determine associations between prenatal psychological stressors and distress with maternal and early life TL, and associations between maternal, newborn and child TL with neurodevelopmental outcomes at 2 years of age.

METHODS

Follow-up TL was measured in a subgroup of African mothers (n = 138) and their newborns (n = 142) and children (n = 96) at 2-years in the Drakenstein Child Health Study. Prenatal symptoms of depression, distress, intimate partner violence, posttraumatic stress-disorder and childhood trauma were measured at 27 weeks gestation. Neurodevelopment was assessed at 2 years using the Bayley Scales of Infant and Toddler Development III. TLs were measured in whole bloods from mothers and their children at 2-years, and cord bloods in newborns.

RESULTS

Maternal prenatal stressors and distress were not significantly associated with TL in mothers or their children at birth or at 2-years. Furthermore, maternal psychological measures were not associated with early-life attrition of TL. Longer TL in children at 2-years was associated (p = 0.04) with higher motor functioning.

LIMITATIONS

Limited numbers of participants and single time-point psychological measures.

CONCLUSIONS

This study is the first to provide information on the association of early life TL with prenatal psychological adversities and neurodevelopmental outcomes in a population of low-income African mothers and their children.

Folic Acid Supplementation during Pregnancy and Its Association with Telomere Length in Children at Four Years: Results from the INMA Birth Cohort Study

This study examined the association between folic acid supplements (FAs) during different periods of pregnancy and offspring telomere length (TL) at age four in 666 children from the INMA study. FAs were self-reported using food-structured questionnaires during three periods of pregnancy (the first three months of pregnancy, from month fourth onward, and the whole pregnancy). For each period, the average daily dosage of FAs was categorised into (i) <400 μg/d, (ii) ≥400 to 999 μg/d, (iii) ≥1000 to 4999 μg/d, and (iv) ≥5000 μg/d. Leucocyte TL at age four was measured using quantitative PCR methods. Multiple robust linear log-level regression models were used to report the % difference among FA categories. During the first period, and compared with children whose mothers were classified in the reference group (<400 μg/d), children whose mothers took higher dosages of FAs showed shorter TL at age four (≥5000 μg/d). When the first and the second periods were mutually adjusted, children whose mothers self-reported ≥5000 μg/d during the first period of pregnancy had a statistically significant shorter TL than their counterparts (% difference: -7.28% [95% CI: -14.42 to -0.13]). Similar trends were observed for the whole period of pregnancy. When the analysis was stratified by sex, the association was more evident in boys (% difference: -13.5% [95% CI: -23.0 to -4.04]), whereas no association was observed in girls. This study suggests that high dosages of FAs in the first pregnancy period may be associated with a shorter TL in children at age four, particularly among boys. Further studies should confirm these results.

A Multi-Omics and Human Biomonitoring Approach to Assessing the Effectiveness of Fortified Balanced Energy-Protein Supplementation on Maternal and Newborn Health in Burkina Faso: A Study Protocol

Fortified balanced energy-protein (BEP) supplementation is a promising intervention for improving maternal health, birth outcomes and infant growth in low- and middle-income countries. This nested biospecimen sub-study aimed to evaluate the physiological effect of multi-micronutrient-fortified BEP supplementation on pregnant and lactating women and their infants. Pregnant women (15-40 years) received either fortified BEP and iron-folic acid (IFA) (intervention) or IFA only (control) throughout pregnancy. The same women were concurrently randomized to receive either a fortified BEP supplement during the first 6 months postpartum in combination with IFA for the first 6 weeks (i.e., intervention) or the postnatal standard of care, which comprised IFA alone for 6 weeks postpartum (i.e., control). Biological specimens were collected at different timepoints. Multi-omics profiles will be characterized to assess the mediating effect of BEP supplementation on the different trial arms and its effect on maternal health, as well as birth and infant growth outcomes. The mediating effect of the exposome in the relationship between BEP supplementation and maternal health, birth outcomes and infant growth were characterized via biomonitoring markers of air pollution, mycotoxins and environmental contaminants. The results will provide holistic insight into the granular physiological effects of prenatal and postnatal BEP supplementation.

Pre-admission ambient air pollution and blood soot particles predict hospitalisation outcomes in COVID-19 patients

BACKGROUND

Air pollution exposure is one of the major risk factors for aggravation of respiratory diseases. We investigated whether exposure to air pollution and accumulated black carbon (BC) particles in blood were associated with coronavirus disease 2019 (COVID-19) disease severity, including the risk for intensive care unit (ICU) admission and duration of hospitalisation.

METHODS

From May 2020 until March 2021, 328 hospitalised COVID-19 patients (29% at intensive care) were recruited from two hospitals in Belgium. Daily exposure levels (from 2016 to 2019) for particulate matter with aerodynamic diameter <2.5 µm and <10 µm (PM2.5 and PM10, respectively), nitrogen dioxide (NO2) and BC were modelled using a high-resolution spatiotemporal model. Blood BC particles (internal exposure to nano-sized particles) were quantified using pulsed laser illumination. Primary clinical parameters and outcomes included duration of hospitalisation and risk of ICU admission.

RESULTS

Independent of potential confounders, an interquartile range (IQR) increase in exposure in the week before admission was associated with increased duration of hospitalisation (PM2.5 +4.13 (95% CI 0.74-7.53) days, PM10 +4.04 (95% CI 1.24-6.83) days and NO2 +4.54 (95% CI 1.53-7.54) days); similar effects were observed for long-term NO2 and BC exposure on hospitalisation duration. These effect sizes for an IQR increase in air pollution on hospitalisation duration were equivalent to the effect of a 10-year increase in age on hospitalisation duration. Furthermore, for an IQR higher blood BC load, the OR for ICU admission was 1.33 (95% CI 1.07-1.65).

CONCLUSIONS

In hospitalised COVID-19 patients, higher pre-admission ambient air pollution and blood BC levels predicted adverse outcomes. Our findings imply that air pollution exposure influences COVID-19 severity and therefore the burden on medical care systems during the COVID-19 pandemic.

Maximal telomerase activity capacity (mTAC) underlies the link between the cortisol response to stress and telomere length

Exposure to various forms of stress has been associated with shorter telomere length (TL). However, the molecular underpinnings of this effect are poorly understood. Based on an understanding of the key role of the reverse transcriptase enzyme telomerase in regulating TL, and building upon our previous work in developing and validating a biomarker of the capacity of cells to express telomerase (maximal telomerase activity capacity (mTAC)), we examine here the hypotheses that mTAC is positively associated with TL and that the effect of stress on TL is mediated by individual differences in mTAC. In a proof-of-principle study of 28 healthy women and men we quantified the cortisol response to a standardized stress challenge, the Trier Social Stress Test (TSST), and we concurrently assessed peripheral blood mononuclear cell (PBMC) mTAC and TL. Our results indicated that higher mTAC levels were associated with longer TL (r = 0.50, p = .01). Moreover, mediational analysis suggested that the effect of the cortisol stress response on TL was mediated by mTAC (completely standardized β = -0.17, bootstrap CI95 %: -0.44 to -0.01). Thus, our findings support the premise that individual differences in the capacity of cells to up-regulate telomerase may represent a key mediator in the link between stress and TL.

The associations of socioeconomic status with incident dementia and Alzheimer's disease are modified by leucocyte telomere length: a population-based cohort study

Socio-economic status (SES) and biological aging are risk factors for dementia, including Alzheimer's disease, however, it is less clear if the associations with SES vary sufficiently across different biological age strata. We used data from 331,066 UK Biobank participants aged 38-73 with mean follow-up of 12 years to examine if associations between SES (assessed by educational attainment, employment status and household income) and dementia and Alzheimer's disease are modified by biological age (assessed by leucocyte telomere length: LTL). Diagnosis of events was ascertained through hospital admissions data. Cox regressions were used to estimate hazard ratios [HRs]. A consistent dose-response relationship was found, with participants in low SES and shorter LTL strata (double-exposed group) reporting 3.28 (95% confidence interval [CI] 2.57-4.20) and 3.44 (95% CI 2.35-5.04) times higher risks of incident dementia and Alzheimer's disease respectively, compared to those of high SES and longer LTL (least-exposed group). Of interest is a synergistic interaction between SES and LTL to increase risk of dementia (RERI 0.57, 95% CI 0.07-1.06) and Alzheimer's disease (RERI 0.79, 95% CI 0.02-1.56). Our findings that SES and biological age (LTL) are synergistic risk factors of dementia and Alzheimer's disease may suggest the need to target interventions among vulnerable sub-groups.

Sedentary Behaviour and Telomere Length Shortening during Early Childhood: Evidence from the Multicentre Prospective INMA Cohort Study

Sedentary behaviour (SB) may be related to telomere length (TL) attrition due to a possible pro-inflammatory effect. This study examined the association between parent-reported sedentary behaviour (SB) and leukocyte TL at the age of 4 and telomere tracking from 4 to 8 years. In the Spanish birth cohort Infancia y Medio Ambiente (INMA) project, we analysed data from children who attended follow-up visits at age 4 (n = 669) and 8 (n = 530). Multiple robust regression models were used to explore the associations between mean daily hours of SB (screen time, other sedentary activities, and total SB) at 4 years categorised into tertiles and TL at 4 years and difference in TL rank between age 4 and 8, respectively. At the age of 4, the results showed that children with the highest screen time (1.6-5.0 h/day) had a shorter TL of -3.9% (95% CI: -7.4, -0.4; p = 0.03) compared with children in the lowest tertile (0.0-1.0 h/day). Between 4 and 8 years, a higher screen time (highest tertile group vs. lowest tertile) was associated with a decrease in the LTL rank of -1.9% (95% CI: -3.8, -0.1; p = 0.03) from 4 to 8 years. Children exposed to a higher screen time at 4 years were more prone to have shorter TL at 4 and between 4 and 8 years of age. This study supports the potential negative effect of SB during childhood on cellular longevity.

Accumulation of Black Carbon Particles in Placenta, Cord Blood, and Childhood Urine in Association with the Intestinal Microbiome Diversity and Composition in Four- to Six-Year-Old Children in the ENVIRONAGE Birth Cohort

BACKGROUND

The gut microbiome plays an essential role in human health. Despite the link between air pollution exposure and various diseases, its association with the gut microbiome during susceptible life periods remains scarce.

OBJECTIVES

In this study, we examined the association between black carbon particles quantified in prenatal and postnatal biological matrices and bacterial richness and diversity measures, and bacterial families.

METHODS

A total of 85 stool samples were collected from 4- to 6-y-old children enrolled in the ENVIRonmental influence ON early AGEing birth cohort. We performed 16S rRNA gene sequencing to calculate bacterial richness and diversity indices (Chao1 richness, Shannon diversity, and Simpson diversity) and the relative abundance of bacterial families. Black carbon particles were quantified via white light generation under femtosecond pulsed laser illumination in placental tissue and cord blood, employed as prenatal exposure biomarkers, and in urine, used as a post-natal exposure biomarker. We used robust multivariable-adjusted linear models to examine the associations between quantified black carbon loads and measures of richness (Chao1 index) and diversity (Shannon and Simpson indices), adjusting for parity, season of delivery, sequencing batch, age, sex, weight and height of the child, and maternal education. Additionally, we performed a differential relative abundance analysis of bacterial families with a correction for sampling fraction bias. Results are expressed as percentage difference for a doubling in black carbon loads with 95% confidence interval (CI).

RESULTS

Two diversity indices were negatively associated with placental black carbon [Shannon: -4.38% (95% CI: -8.31%, -0.28%); Simpson: -0.90% (95% CI: -1.76%, -0.04%)], cord blood black carbon [Shannon: -3.38% (95% CI: -5.66%, -0.84%); Simpson: -0.91 (95% CI: -1.66%, -0.16%)], and urinary black carbon [Shannon: -3.39% (95% CI: -5.77%, -0.94%); Simpson: -0.89% (95% CI: -1.37%, -0.40%)]. The explained variance of black carbon on the above indices varied from 6.1% to 16.6%. No statistically significant associations were found between black carbon load and the Chao1 richness index. After multiple testing correction, placental black carbon was negatively associated with relative abundance of the bacterial families Defluviitaleaceae and Marinifilaceae, and urinary black carbon with Christensenellaceae and Coriobacteriaceae; associations with cord blood black carbon were not statistically significant after correction.

CONCLUSION

Black carbon particles quantified in prenatal and postnatal biological matrices were associated with the composition and diversity of the childhood intestinal microbiome. These findings address the influential role of exposure to air pollution during pregnancy and early life in human health. https://doi.org/10.1289/EHP11257.

Demographic and health predictors of telomere length during adolescence

Telomere length (TL) is proposed to play a mechanistic role in how the exposome affects health outcomes. Little is known about TL during adolescence, a developmental period during which precursors of adult-onset health problems often emerge. We examined health and demographic sources of variation in TL in 899 youth aged 11-17. Demographic and health information included age, sex, race, household income, caregiver age and marital status, youth tobacco exposure, body mass index, pubertal status, health problems, medication use, and season of data collection. Genomic DNA was extracted from saliva, and T/S ratios were computed following qPCR. Age, race, season of data collection, and household income were associated with the telomere to single copy (T/S) ratio. We found that T/S ratios were larger at younger ages, among Black youth, for saliva collected during autumn and winter, and among households with higher income. Analyses stratified by race revealed that the association between age and T/S ratio was present for Black youth, that season of collection was present across races, but that family demographic associations with T/S ratio varied by race. The results provide information for future telomere research and highlight adolescence as a potentially important developmental phase for racial disparities in telomere shortening and health.

Adverse associations of long-term exposure to ambient ozone with molecular biomarkers of aging alleviated by residential greenness in rural Chinese adults

BACKGROUND

Both ambient ozone exposure and residential greenness are linked to the aging process. However, their interactive effect on molecular biomarkers of aging (telomere length (TL) and mitochondrial DNA copy number (mtDNA-CN)) remains unclear.

METHODS

This study was conducted among 6418 rural Chinese adults. The concentration of ambient ozone was assessed using a random forest model. Residential greenness was represented by the normalized difference vegetation index (NDVI). Molecular biomarkers of aging (relative TL and relative mtDNA-CN) were determined by quantitative real-time polymerase chain reaction. Generalized linear regression models were applied to investigate the independent and combined effects of ambient ozone and residential greenness on relative TL and relative mtDNA-CN.

RESULTS

The estimated percent changes and 95 % confidence intervals (CIs) of relative TL in response to per-unit increase in ambient ozone were -22.43 % (-23.74 %, -21.18 %), -14.19 % (-15.63 %, -12.72 %) and -4.50 % (-6.57 %, -2.27 %) for participants with low (NDVI ≤ 0.53), moderate (0.54-0.55) and high (≥0.56) residential greenness exposure, respectively, while the corresponding figures of relative mtDNA-CN were -12.63 % (-13.84 %, -11.31 %), -9.52 % (-10.60 %, -8.33 %) and 2.12 % (0.20 %, 4.19 %). Furthermore, negative interactive effects between ambient ozone and residential greenness exposure on molecular biomarkers of aging were observed (P_{for interaction} < 0.001 for relative TL, and 0.098 for relative mtDNA-CN).

CONCLUSIONS

Long-term exposure to high concentrations of ambient ozone and low residential greenness was associated with decreased mtDNA-CN and shortened TL. The adverse effect of ambient ozone exposure on molecular biomarkers of aging may be attenuated by increased residential greenness.

Examining attachment, cortisol secretion, and cognitive neurodevelopment in preschoolers and its predictive value for telomere length at age seven

Background

Secure attachment reflects caregiver-child relationship in which the caregiver is responsive when support and comforting are needed by the child. This pattern of bond has an important buffering role in the response to stress by the reduction of the negative experience and its associated physiological response. Disruption of the physiological stress system is thought to be a central mechanism by which early care impacts children. Early life stress causes cellular and molecular changes in brain regions associated with cognitive functions that are fundamental for early learning.

Methods

The association between attachment, cortisol response before and after the Strange Situation Experiment, and neurodevelopment was examined in a sample of 107 preschoolers at age three. Also, the predictive effect of cortisol reactivity and attachment on telomere length at age seven was investigated in a followed-up sample of 77 children.

Results

Children with insecure attachment had higher cortisol secretion and poorer neurodevelopmental skills at age three. A significant cortisol change was observed across the experiment with non-significant interaction with attachment. The attachment and neurodevelopment association was not mediated by cortisol secretion. Preschoolers' attachment and cortisol did not associate nor interacted to predict telomere length at age seven.

Conclusion

These findings add evidence to the detrimental effects of insecure attachment as an aggravator of the physiological response to stress and poorer neurodevelopment during the preschool period. Although attachment and cortisol were not predictive of telomere length, intervention policies that promote secure attachment are more likely to positively echo on several health domains.

A multi-exposure approach to study telomere dynamics in childhood: A role for residential green space and waist circumference

BACKGROUND

Telomeres are vulnerable to various environmental exposures and lifestyle factors, encompassed in the exposome. Recent research shows that telomere length is substantially determined early in life and that exposures in childhood may have important consequences in setting later life telomere length.

OBJECTIVES

We explore in a child population the associations of 17 exposures with telomere length and longitudinal telomere change.

METHODS

Children (2.8-10.3y at baseline, 51.3% boys) were followed-up for five to seven years. Relative telomere length was measured at baseline and follow-up using quantitative real-time PCR. Exposures and lifestyle factors included: body composition (body mass index and waist circumference), dietary habits (sugar- and fat-rich food intake, vegetables and fruit intake), psychosocial stress (events, emotions, behaviour), sleep duration, physical activity, and residential environmental quality (longterm black carbon, particulate matter exposure, and residential green space). Cross-sectional (n=182) and longitudinal (n=150) analyses were assessed using linear regression models, adjusting for age, sex, socioeconomic status and multiple testing.

RESULTS

Our longitudinal analyses showed that higher residential green space at baseline was associated with (β=0.261, p=0.002) lower telomere attrition and that children with a higher waist circumference at baseline showed a higher telomere attrition (β=-0.287, p=0.001). These two predictors were confirmed via LASSO variable selection and correction for multiple testing. In addition, children with more unhealthy exposures at baseline had a significantly higher telomere attrition over the follow-up period compared to children with more healthy exposures (β=-0.200, p=0.017).

DISCUSSION

Waist circumference and residential green space were identified as predictors associated with telomere attrition in childhood. These results further support the advantages of a healthy lifestyle from early age onwards and the importance of a green environment to promote molecular longevity from childhood onwards.

Vitamin D Levels During Pregnancy Are Associated With Offspring Telomere Length: A Longitudinal Mother-Child Study

CONTEXT

Leukocyte telomere length (LTL) is a biomarker of biological aging and is associated with metabolic diseases such as type 2 diabetes. Insufficient maternal vitamin D was associated with increased risk for many diseases and adverse later life outcomes.

OBJECTIVE

This study investigates the relationship between vitamin D levels and offspring LTL at early life.

METHODS

This observational, longitudinal, hospital-based cohort study included eligible mother-child pairs from the HAPO Hong Kong Field Centre, with 853 offspring at age 6.96 ± 0.44 (mean ± SD) years. LTL was measured using real-time polymerase chain reaction while serum vitamin D metabolites 25(OH)D2, 25(OH)D3, and 3-epi-25(OH)D3 were measured in maternal blood (at gestation 24-32 weeks) and cord blood by liquid chromatography-mass spectrometry.

RESULTS

LTL at follow-up was significantly shorter in boys compared with girls (P < 0.001) at age 7. Childhood LTL was negatively associated with childhood BMI (β ± SE = -0.016 ± 0.007)(P = 0.02) and HOMA-IR (β ± SE = -0.065 ± 0.021)(P = 0.002). Multiple linear regression was used to evaluate the relationship between 25(OH)D and LTL, with covariate adjustments. Childhood LTL was positively correlated with total maternal 25(OH)D (0.048 ± 0.017) (P = 0.004) and maternal 3-epi-25(OH)D3 (0.05 ± 0.017) (P = 0.003), even after adjustment for covariates. A similar association was also noted for cord 3-epi-25(OH)D3 (0.037 ± 0.018) (P = 0.035) after adjustment for offspring sex and age.

CONCLUSION

Our findings suggest 25(OH)D3 and 3-epi-25(OH)D3 in utero may impact on childhood LTLs, highlighting a potential link between maternal vitamin D and biological aging.

Children who sleep more may have longer telomeres: evidence from a longitudinal population study in Spain

BACKGROUND

Inadequate sleep duration has been suggested as a chronic stressor associated with changes in telomere length (TL). This study aimed to explore the association between sleep duration and TL using the INMA birth cohort study data.

METHODS

A total of 1014 children were included in this study (cross-sectional: 686; longitudinal: 872). Sleep duration (h/day) was reported by caregivers at 4 years and classified into tertiles (7-10 h/day; >10-11 h/day; >11-14 h/day). Leucocyte TL at 4 and 7-9 years were measured using quantitative PCR methods. Multiple robust linear regression models, through log-level regression models, were used to report the % of difference among tertiles of sleep duration.

RESULTS

In comparison to children who slept between >10 and 11 h/day, those in the highest category (more than 11 h/day) had 8.5% (95% CI: 3.56-13.6) longer telomeres at 4 years. Longitudinal analysis showed no significant association between sleep duration at 4 years and TL at 7-9 years.

CONCLUSION

Children who slept more hours per day had longer TL at 4 years independently of a wide range of confounder factors. Environmental conditions, such as sleep duration, might have a major impact on TL during the first years of life.

IMPACT

Telomere length was longer in children with longer sleep duration (>11 h/day) independently of a wide range of confounder factors at age 4 and remained consistent by sex. Sleep routines are encouraged to promote positive child development, like the number of hours of sleep duration. Considering the complex biology of telomere length, future studies still need to elucidate which biological pathways might explain the association between sleep duration and telomere length.

Association of Newborn Telomere Length With Blood Pressure in Childhood

IMPORTANCE

Adult telomere length (TL) is a biological marker of aging associated with vascular health. TL at birth is associated with later life TL and may contain early biological information of later life cardiovascular health and disease.

OBJECTIVE

To evaluate whether newborn TL is associated with early life blood pressure differences in childhood.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study was part of the ENVIRONAGE (Environmental Influence on Aging in Early Life) study, a birth cohort of Belgian mother-child pairs with recruitment at birth and a median follow-up of 4.5 years conducted between October 2014 and July 2021. Participants included for analysis provided full data for evaluation at follow-up visit. Data analysis was conducted between August and September 2021.

MAIN OUTCOMES AND MEASURES

Cord blood and placental average relative TL were measured at birth using quantitative polymerase chain reaction (qPCR). Systolic, diastolic, and mean arterial pressure (MAP) were evaluated at follow-up. High childhood blood pressure (standardized for child age, sex, and height) was defined following the 2017 American Academy of Pediatrics guidelines. Multivariable adjusted linear and logistic regression models were used to associate newborn TL and blood pressure indicators in childhood.

RESULTS

This study included 485 newborn children (52.8% girls) with a mean (SD) age of 4.6 (0.4) years at the follow-up visit. Newborn TL was associated with lower blood pressure in childhood. A 1-IQR increase in cord blood TL was associated with a -1.54 mm Hg (95% CI, -2.36 to -0.72 mm Hg) lower diastolic blood pressure and -1.18 mm Hg (95% CI, -1.89 to -0.46 mm Hg) lower MAP. No association was observed with systolic blood pressure. Furthermore, a 1-IQR increase in cord blood TL was associated with lower odds of having high blood pressure at the age of 4 to 6 years (adjusted OR, 0.72; 95% CI, 0.53 to 0.98). In placenta, a 1-IQR increase in TL was associated with a -0.96 mm Hg (95% CI, -1.72 to -0.21 mm Hg) lower diastolic, -0.88 mm Hg (95% CI, -1.54 to -0.22 mm Hg) lower MAP, and a lower adjusted OR of 0.69 (95% CI, 0.52 to 0.92) for having a high blood pressure in childhood.

CONCLUSIONS AND RELEVANCE

In this prospective birth cohort study, variation in early life blood pressure at school-age was associated with TL at birth. Cardiovascular health may to some extent be programmed at birth, and these results suggest that TL entails a biological mechanism in this programming.

Assessing socioeconomic bias in machine learning algorithms in health care: a case study of the HOUSES index

OBJECTIVE

Artificial intelligence (AI) models may propagate harmful biases in performance and hence negatively affect the underserved. We aimed to assess the degree to which data quality of electronic health records (EHRs) affected by inequities related to low socioeconomic status (SES), results in differential performance of AI models across SES.

MATERIALS AND METHODS

This study utilized existing machine learning models for predicting asthma exacerbation in children with asthma. We compared balanced error rate (BER) against different SES levels measured by HOUsing-based SocioEconomic Status measure (HOUSES) index. As a possible mechanism for differential performance, we also compared incompleteness of EHR information relevant to asthma care by SES.

RESULTS

Asthmatic children with lower SES had larger BER than those with higher SES (eg, ratio = 1.35 for HOUSES Q1 vs Q2-Q4) and had a higher proportion of missing information relevant to asthma care (eg, 41% vs 24% for missing asthma severity and 12% vs 9.8% for undiagnosed asthma despite meeting asthma criteria).

DISCUSSION

Our study suggests that lower SES is associated with worse predictive model performance. It also highlights the potential role of incomplete EHR data in this differential performance and suggests a way to mitigate this bias.

CONCLUSION

The HOUSES index allows AI researchers to assess bias in predictive model performance by SES. Although our case study was based on a small sample size and a single-site study, the study results highlight a potential strategy for identifying bias by using an innovative SES measure.

Social Determinants of Cardiovascular Disease

Social determinants of health (SDoH), which encompass the economic, social, environmental, and psychosocial factors that influence health, play a significant role in the development of cardiovascular disease (CVD) risk factors as well as CVD morbidity and mortality. The COVID-19 pandemic and the current social justice movement sparked by the death of George Floyd have laid bare long-existing health inequities in our society driven by SDoH. Despite a recent focus on these structural drivers of health disparities, the impact of SDoH on cardiovascular health and CVD outcomes remains understudied and incompletely understood. To further investigate the mechanisms connecting SDoH and CVD, and ultimately design targeted and effective interventions, it is important to foster interdisciplinary efforts that incorporate translational, epidemiological, and clinical research in examining SDoH-CVD relationships. This review aims to facilitate research coordination and intervention development by providing an evidence-based framework for SDoH rooted in the lived experiences of marginalized populations. Our framework highlights critical structural/socioeconomic, environmental, and psychosocial factors most strongly associated with CVD and explores several of the underlying biologic mechanisms connecting SDoH to CVD pathogenesis, including excess stress hormones, inflammation, immune cell function, and cellular aging. We present landmark studies and recent findings about SDoH in our framework, with careful consideration of the constructs and measures utilized. Finally, we provide a roadmap for future SDoH research focused on individual, clinical, and policy approaches directed towards developing multilevel community-engaged interventions to promote cardiovascular health.

The impact of neighborhood context on telomere length: A systematic review

A growing body of research demonstrates the association between neighborhood context and health. The underlying biological mechanisms of this association are not fully understood. We conducted a systematic review of studies that investigated the association between neighborhood context and telomere length (TL), a DNA-protein complex that shortens after cell division. Short TL is linked to age-related diseases and may be impacted by chronic stress. Nineteen eligible articles identified through PubMed and Scopus met inclusion criteria. Results demonstrated inconsistent support for the relationship between neighborhood disadvantage and short TL. However, findings across several studies provide evidence for an inverse association between perceived neighborhood problems and TL, suggesting that TL may be an important factor in understanding health vulnerabilities associated specifically with negative perceptions of the neighborhood context.

Variability in newborn telomere length is explained by inheritance and intrauterine environment

BACKGROUND

Telomere length (TL) and its attrition are important indicators of physiological stress and biological aging and hence may vary among individuals of the same age. This variation is apparent even in newborns, suggesting potential effects of parental factors and the intrauterine environment on TL of the growing fetus.

METHODS

Average relative TLs of newborns (cord tissue, N = 950) and mothers (buffy coat collected at 26-28 weeks of gestation, N = 892) were measured in a birth cohort. This study provides a comprehensive analysis of the effects of heritable factors, socioeconomic status, and in utero exposures linked with maternal nutrition, cardiometabolic health, and mental well-being on the newborn TL. The association between maternal TL and antenatal maternal health was also studied.

RESULTS

Longer maternal TL (β = 0.14, P = 1.99E-05) and higher paternal age (β = 0.10, P = 3.73E-03) were positively associated with newborn TL. Genome-wide association studies on newborn and maternal TLs identified 6 genetic variants in a strong linkage disequilibrium on chromosome 3q26.2 (Tag SNP-LRRC34-rs10936600: P_meta = 5.95E-08). Mothers with higher anxiety scores, elevated fasting blood glucose, lower plasma insulin-like growth factor-binding protein 3 and vitamin B12 levels, and active smoking status during pregnancy showed a higher risk of giving birth to offspring with shorter TL. There were sex-related differences in the factors explaining newborn TL variation. Variation in female newborn TL was best explained by maternal TL, mental health, and plasma vitamin B12 levels, while that in male newborn TL was best explained by paternal age, maternal education, and metabolic health. Mother's TL was associated with her own metabolic health and nutrient status, which may have transgenerational effects on offspring TL.

CONCLUSIONS

Our findings provide a comprehensive understanding of the heritable and environmental factors and their relative contributions to the initial setting of TL and programing of longevity in early life. This study provides valuable insights for preventing in utero telomere attrition by improving the antenatal health of mothers via targeting the modifiable factors.

TRIAL REGISTRATION

ClinicalTrials.gov , NCT01174875. Registered on 1 July 2010.

Prenatal exposure to maternal psychological distress and telomere length in childhood

Telomere length (TL) is a biological marker of cellular aging, and shorter TL in adulthood is associated with increased morbidity and mortality risk. It is likely that these differences in TL are established long before adulthood, and there is growing evidence that TL can reflect prenatal experiences. Although maternal prenatal distress predicts newborn TL, it is unknown whether the relation between prenatal exposure to maternal distress and child TL persists through childhood. The purpose of the current longitudinal, prospective study is to examine the relation between prenatal exposure to maternal distress (perceived stress, depressive symptoms, pregnancy-related anxiety) and TL in childhood. Participants included 102 children (54 girls) and their mothers. Mothers' distress was assessed five times during pregnancy, at 12 weeks postpartum, and at the time of child telomere measurement between 6 and 16 years of age. Maternal distress during pregnancy predicted shorter offspring TL in childhood, even after accounting for postnatal exposure to maternal distress and other covariates. These findings indicate that maternal mental health predicts offspring TL biology later in childhood than previously observed. This study bolsters claims that telomere biology is subject to fetal programming and highlights the importance of supporting maternal mental health during pregnancy.

Immune and Epigenetic Pathways Linking Childhood Adversity and Health Across the Lifespan

Childhood adversity is associated with a host of mental and physical health problems across the lifespan. Individuals who have experienced childhood adversity (e.g., child abuse and neglect, family conflict, poor parent/child relationships, low socioeconomic status or extreme poverty) are at a greater risk for morbidity and premature mortality than those not exposed to childhood adversity. Several mechanisms likely contribute to the relationship between childhood adversity and health across the lifespan (e.g., health behaviors, cardiovascular reactivity). In this paper, we review a large body of research within the field of psychoneuroimmunology, demonstrating the relationship between early life stress and alterations of the immune system. We first review the literature demonstrating that childhood adversity is associated with immune dysregulation across different indices, including proinflammatory cytokine production (and its impact on telomere length), illness and infection susceptibility, latent herpesvirus reactivation, and immune response to a tumor. We then summarize the growing literature on how childhood adversity may alter epigenetic processes. Finally, we propose future directions related to this work that have basic and applied implications.

Longitudinal Follow-Up of Blood Telomere Length in HIV-Exposed Uninfected Children Having Received One Year of Lopinavir/Ritonavir or Lamivudine as Prophylaxis

Telomere shortening can be enhanced upon human immunodeficiency virus (HIV) infection and by antiretroviral (ARV) exposures. The aim of this study was to evaluate the acute and long-term effect on telomere shortening of two ARV prophylaxes, lopinavir/ritonavir (LPV/r) and lamivudine (3TC), administered to children who are HIV-exposed uninfected (CHEU) to prevent HIV acquisition through breastfeeding during the first year of life, and to investigate the relationship between telomere shortening and health outcomes at six years of age. We included 198 CHEU and measured telomere length at seven days of life, at week-50 and at six years (year-6) using quantitative polymerase chain reaction. At week-50, telomere shortening was observed among 44.3% of CHEU, irrespective of the prophylactic treatment. Furthermore, this telomere shortening was neither associated with poor growth indicators nor neuropsychological outcomes at year-6, except for motor abilities (MABC test n = 127, β = -3.61, 95%CI: -7.08, -0.14; p = 0.04). Safety data on telomere shortening for infant HIV prophylaxis are scarce. Its association with reduced motor abilities deserves further attention among CHEU but also HIV-infected children receiving ARV treatment.

Symptoms of Prenatal Depression Associated with Shorter Telomeres in Female Placenta

BACKGROUND

Depression is a common mood disorder during pregnancy impacting one in every seven women. Children exposed to prenatal depression are more likely to be born at a low birth weight and develop chronic diseases later in life. A proposed hypothesis for this relationship between early exposure to adversity and poor outcomes is accelerated aging. Telomere length has been used as a biomarker of cellular aging. We used high-resolution telomere length analysis to examine the relationship between placental telomere length distributions and maternal mood symptoms in pregnancy.

METHODS

This study utilised samples from the longitudinal Grown in Wales (GiW) study. Women participating in this study were recruited at their presurgical appointment prior to a term elective caesarean section (ELCS). Women completed the Edinburgh Postnatal Depression Scale (EPDS) and trait subscale of the State-Trait Anxiety Inventory (STAI). Telomere length distributions were generated using single telomere length analysis (STELA) in 109 term placenta (37-42 weeks). Multiple linear regression was performed to examine the relationship between maternally reported symptoms of depression and anxiety at term and mean placental telomere length.

RESULTS

Prenatal depression symptoms were significantly negatively associated with XpYp telomere length in female placenta (B = -0.098, p = 0.026, 95% CI -0.184, -0.012). There was no association between maternal depression symptoms and telomere length in male placenta (B = 0.022, p = 0.586, 95% CI -0.059, 0.103). There was no association with anxiety symptoms and telomere length for either sex.

CONCLUSION

Maternal prenatal depression is associated with sex-specific differences in term placental telomeres. Telomere shortening in female placenta may indicate accelerated placental aging.

Family socioeconomic status and child telomere length among the Samburu of Kenya

Previous research in high-income countries suggests that children from families with lower socioeconomic status (SES) tend to have shorter telomere length - a biomarker of stress and cell aging - than children from families with greater social and economic resources. However, little is known about predictors of child telomere length in low-income settings. Data for the current study are from a sample of 214 Samburu children aged 1-9 years. The Samburu are semi-nomadic pastoralists who live in the Rift Valley of north-central Kenya. Samburu livelihood is based primarily on livestock, and polygynous marriage is common. Drawing on prior ethnographic research, we measured 14 culturally relevant indicators of family SES, including mother's education, head of household's education, whether the child is currently attending school, household spending, mother's employment history, head of household's employment history, mother's perceived wealth, whether the child lives in a modern house, livestock holdings (total, cows, sheep/goats, and camels), mother's wife number, and whether the child lives in a polygynous household. Telomere length was measured in salivary DNA by the quantitative polymerase chain reaction (qPCR) method. Using latent class analysis, we identified four groups of children that are similar based on the 14 indicators of family SES: Lower SES; Middle SES, Traditional; Middle SES, Modern; and Higher SES. SES classes were not significantly associated with child telomere length. In models examining individual indicators of SES, we found that telomere length was 0.57 standard deviations greater for children who lived in families in the lowest quartile of total livestock holdings compared to those in the highest quartile (b = 0.57, p = 0.03). While additional research is needed to identify the mechanisms underlying this counterintuitive finding, the current study highlights the importance of cultural context in shaping the social gradient in health.

Mixture effects of prenatal exposure to per- and polyfluoroalkyl substances and polybrominated diphenyl ethers on maternal and newborn telomere length

BACKGROUND

Per- and polyfluoroalkyl substances (PFAS) and polybrominated diphenyl ethers (PBDEs) are endocrine disrupting chemicals with widespread exposures across the U.S. given their abundance in consumer products. PFAS and PBDEs are associated with reproductive toxicity and adverse health outcomes, including certain cancers. PFAS and PBDEs may affect health through alternations in telomere length. In this study, we examined joint associations between prenatal exposure to PFAS, PBDEs, and maternal and newborn telomere length using mixture analyses, to characterize effects of cumulative environmental chemical exposures.

METHODS

Study participants were enrolled in the Chemicals in Our Bodies (CIOB) study, a demographically diverse cohort of pregnant people and children in San Francisco, CA. Seven PFAS (ng/mL) and four PBDEs (ng/g lipid) were measured in second trimester maternal serum samples. Telomere length (T/S ratio) was measured in delivery cord blood of 292 newborns and 110 second trimester maternal whole blood samples. Quantile g-computation was used to assess the joint associations between groups of PFAS and PBDEs and newborn and maternal telomere length. Groups considered were: (1) all PFAS and PBDEs combined, (2) PFAS, and (3) PBDEs. Maternal and newborn telomere length were modeled as separate outcomes.

RESULTS

T/S ratios in newborn cord and maternal whole blood were moderately correlated (Spearman ρ = 0.31). In mixtures analyses, a simultaneous one quartile increase in all PFAS and PBDEs was associated with a small increase in newborn (mean change per quartile increase = 0.03, 95% confidence interval [CI] = -0.03, 0.08) and maternal telomere length (mean change per quartile increase = 0.03 (95% CI = -0.03, 0.09). When restricted to maternal-fetal paired samples (N = 76), increasing all PFAS and PBDEs combined was associated with a strong, positive increase in newborn telomere length (mean change per quartile increase = 0.16, 95% CI = 0.03, 0.28). These associations were primarily driven by PFAS (mean change per quartile increase = 0.11 [95% CI = 0.01, 0.22]). No associations were observed with maternal telomere length among paired samples.

CONCLUSIONS

Our findings suggest that PFAS and PBDEs may be positively associated with newborn telomere length.

Maternal Vitamin D and Newborn Telomere Length

Nutrition is important during pregnancy for offspring health. Gestational vitamin D intake may prevent several adverse outcomes and might have an influence on offspring telomere length (TL). In this study, we want to assess the association between maternal vitamin D intake during pregnancy and newborn TL, as reflected by cord blood TL. We studied mother–child pairs enrolled in the Maternal Nutrition and Offspring’s Epigenome (MANOE) cohort, Leuven, Belgium. To calculate the dietary vitamin D intake, 108 women were asked to keep track of their diet using the seven-day estimated diet record (EDR) method. TL was assessed in 108 cord blood using a quantitative real-time PCR method. In each trimester of pregnancy, maternal serum 25-hydroxyvitamin D (25-OHD) concentration was measured. We observed a positive association (β = 0.009, p-value = 0.036) between newborn average relative TL and maternal vitamin D intake (diet + supplement) during the first trimester. In contrast, we found no association between average relative TL of the newborn and mean maternal serum 25-OHD concentrations during pregnancy. To conclude, vitamin D intake (diet + supplements), specifically during the first trimester of pregnancy, is an important factor associated with TL at birth.

Telomere Shortening and Psychiatric Disorders: A Systematic Review

Telomeres are aging biomarkers, as they shorten while cells undergo mitosis. The aim of this study was to evaluate whether psychiatric disorders marked by psychological distress lead to alterations to telomere length (TL), corroborating the hypothesis that mental disorders might have a deeper impact on our physiology and aging than it was previously thought. A systematic search of the literature using MeSH descriptors of psychological distress ("Traumatic Stress Disorder" or "Anxiety Disorder" or "depression") and telomere length ("cellular senescence", "oxidative stress" and "telomere") was conducted on PubMed, Cochrane Library and ScienceDirect databases. A total of 56 studies (113,699 patients) measured the TL from individuals diagnosed with anxiety, depression and posttraumatic disorders and compared them with those from healthy subjects. Overall, TL negatively associates with distress-related mental disorders. The possible underlying molecular mechanisms that underly psychiatric diseases to telomere shortening include oxidative stress, inflammation and mitochondrial dysfunction linking. It is still unclear whether psychological distress is either a cause or a consequence of telomere shortening.

Different epigenetic signatures of newborn telomere length and telomere attrition rate in early life

Telomere length (TL) and telomere shortening are biological indicators of aging, and epigenetic associates have been found for TL in adults. However, the role of epigenetic signatures in setting newborn TL and early life telomere dynamics is unknown. In the present study, based on 247 participating newborns from the ENVIRONAGE birth cohort, whole-genome DNA methylation, profiled on the Illumina MethylationEPIC BeadChip microarray, and TL were measured in cord blood. In a follow-up visit at a mean age of 4.58 years, leukocyte TL was evaluated. We combined an epigenome-wide association study and a statistical learning method with re-sampling to select CpGs and their two-way interactions to model baseline (cord blood) TL and early-life telomere attrition rate, where distinct epigenetic signatures were identified for the two outcomes. In addition, a stronger epigenetic regulation was suggested in setting newborn TL than that of telomere dynamics in early life: 47 CpGs and 7 between-CpG interactions explained 76% of the variance in baseline TLs, while 72% of the total variance in telomere attrition rate was explained by 31 CpGs and 5 interactions. Functional enrichment analysis based on the selected CpGs in the two models revealed GLUT4 translocation and immune cell signaling pathways, respectively. These CpGs and interactions, as well as the cellular pathways, are potential novel targets of further investigation of telomere biology and aging.

Newborn telomere length predicts later life telomere length: Tracking telomere length from birth to child- and adulthood

Background

Telomere length (TL) is considered a biological marker of aging and may indicate age-related disease susceptibility. Adults and children show a fixed ranking and tracking of TL over time. However, the contribution of an individual's initial birth TL to their later life TL is unknown. We evaluated change and tracking of TL from birth to child- and adulthood.

Methods

Telomere length at birth was measured using qPCR in two independent prospective birth cohorts. After a median follow-up period of 4 years in ENVIRONAGE (n = 273) we assessed leukocyte telomere length (LTL) and after 23 years in EFPTS (n = 164) buccal TL was assessed. Correlations and multivariable regression models were applied to study telomere tracking and determinants of TL change from birth onwards.

Findings

In children, LTL at the age of 4 correlates with TL at the start of life both in cord blood (r = 0.71, P < 0.0001;) and placenta (r = 0.60, P < 0.0001) and was –11.2% and –33.1% shorter, respectively. In adulthood, buccal TL at the age of 23 correlates with placental TL (r = 0.46, P < 0.0001) and was –35.9% shorter. TL attrition was higher in individuals with longer birth TL. However, based on TL ranking, individuals do not tend to change dramatically from TL rank after 4 or 23 years of follow-up. Finally, longer maternal TL associates with lower telomere attrition in the next generation.

Interpretation

The high prediction of newborn TL for later life TL, and stable TL ranking from birth onwards underscores the importance of understanding the initial setting of newborn TL and its significance for later life.

Funding

European Research Council (ERC-StG310898) and Flemish Scientific Fund (12X9620N).

Pregnancy by Assisted Reproductive Technology Is Associated with Shorter Telomere Length in Neonates

Telomere length (TL) influences the development of lifestyle-related diseases, and neonatal TL may influence their prevalence. Various factors have been reported to affect neonatal TL. Although the fetus is exposed to multiple conditions in utero, the main factors affecting the shortening of neonatal TL are still not known. In this study, we sought to identify factors that influence fetal TL. A total of 578 mother-newborn pairs were included for TL analysis. TL was measured in genomic DNA extracted from cord blood samples using quantitative PCR. The clinical factors examined at enrollment included the following intrauterine environmental factors: maternal age, assisted reproductive technology (ART) used, body mass index (BMI), gestational diabetes mellitus (GDM), maternal stress, smoking, alcohol consumption, preterm delivery, small-for-gestational-age, neonatal sex, and placental weight. Univariate and multivariate regression analyses were used to verify the relationship between neonatal TL and these clinical factors. The median neonatal TL to single-copy gene ratio was 1.0. Pregnancy with ART was among the 11 factors associated with shorter neonatal TL. From multiple regression analysis, we determined that neonatal TL was significantly shorter for pregnancies in the ART group than in the other groups. We conclude that pregnancy with ART is associated with shorter neonatal TL.

Prenatal toxic metal mixture exposure and newborn telomere length: Modification by maternal antioxidant intake

BACKGROUND

Telomere length (TL) predicts the onset of cellular senescence and correlates with longevity and age-related disease risk. While telomeres erode throughout life, adults display fixed ranking and tracking of TL, supporting the importance of the early environment in determining inter-individual variability across the life course. Given their guanine-rich structure, telomeres are highly susceptible to oxidative stress (OS). We examined maternal metal exposure, which can induce OS, in relation to newborn TL. We also considered the modifying role of maternal antioxidant intake.

METHODS

Analyses included 100 mother-newborn pairs enrolled in the Boston and New York City-based PRogramming of Intergenerational Stress Mechanisms (PRISM) pregnancy cohort. We measured As, Ba, Cd, Ni, and Pb in maternal late-pregnancy urine by ICP-MS and quantified relative leukocyte TL (rLTL) in cord blood using qPCR. We used Weighted Quantile Sum (WQS) regression to estimate the metal mixture - rLTL association and conducted repeated holdout validation to improve the stability of estimates across data partitions. We examined models stratified by high (>median) versus low (≤median) maternal antioxidant intake, estimated from Block98 Food Frequency Questionnaires. We considered urinary creatinine, week of urine collection, maternal age, and race/ethnicity as covariates.

RESULTS

In adjusted models, urinary metals were inversely associated with newborn rLTL (βWQS = -0.50, 95% CI: -0.78, -0.21). The top metals contributing to the negative association included Ba (weight: 35.4%), Cd (24.5%) and Pb (26.9%). In models stratified by antioxidant intake, the significant inverse association between metals and rLTL remained only among mothers with low antioxidant intake (low: βWQS = -0.92, 95% CI: -1.53, -0.30; high: βWQS = -0.03, 95% CI: -0.58, 0.52). Results were similar in unadjusted models.

CONCLUSIONS

Relative LTL was shorter among newborns of mothers with higher exposure to metals during pregnancy. Higher maternal antioxidant intake may mitigate the negative influence of metals on newborn rLTL.