Indicator Of Biological Aging Research Articles

Cognitive performance in survivors of breast cancer and markers of biological aging.

Biological aging pathways accelerated by cancer treatments may be a mechanism for cognitive impairment in cancer survivors. The goal of the current study was to examine whether indicators of biological aging, namely elevated levels of DNA damage, reduced telomerase enzymatic activity, and shorter peripheral blood mononuclear cell (PBMC) telomere length (TL) would be related to cognitive function in a cohort of survivors of breast cancer. The authors evaluated a cross-sectional sample of 94 women aged 36 to 69 years who were treated for early-stage breast cancer 3 to 6 years previously. Leukocyte DNA damage, PBMC telomerase enzymatic activity, PBMC TL, and the inflammatory marker soluble tumor necrosis factor receptor II (sTNF-RII) were determined from blood samples. Cognitive function was assessed using a neuropsychological test battery and self-report. Linear regression models examined the relationship between biological aging predictors and cognitive outcomes. Both higher DNA damage and lower telomerase were found to be statistically significantly related to lower executive function scores adjusting for age, body mass index, race, years from treatment, and intelligence score (standardized coefficients [B], -0.23 and 0.30; all P values <.05). In addition, lower telomerase activity was associated with worse attention and motor speed scores (B values, 0.30 and 0.24; P &lt;.05). sTNF-RII and TL were found to be unrelated to any of the neurocognitive domains. The results of the current study suggest a significant association between measures of biological aging and objective measures of cognitive performance in survivors of breast cancer. Future prospective studies are needed to confirm a causal role of biological aging as a driver of declines in cognitive function after cancer treatment.

Justice for all? Beliefs about justice for self and others and telomere length in African Americans.

Believing in justice can protect health. Among marginalized racial minorities however, both endorsing and rejecting beliefs about justice might be critical. The current research examined links between African Americans' beliefs about justice for self and for others and telomere length (TL)-an indicator of biological aging that is increasingly implicated in racial health disparities, with shorter telomeres indicating poorer health. Healthy African Americans (N = 118; 30% male; M age = 31.63 years) completed individual differences measures of justice beliefs for self and others and then provided dried blood spot samples that were assayed for TL. We expected that a belief in justice for self would be positively associated with TL, whereas a belief in justice for others would be negatively associated. A significant 3-way interaction with chronological age confirmed this hypothesis-among older African Americans, TL was positively associated with believing in justice for self, but only when this belief was accompanied by a weak endorsement of the belief in justice for others. Findings underscore that for racial minorities, health might be best protected when justice beliefs are both endorsed and rebuffed. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Error rates for unvalidated medical age assessment procedures

During 2014–2015, Sweden received asylum applications from more than 240,000 people, of which more than 40,000 were termed unaccompanied minors. In a large number of cases, claims by asylum seekers of being below 18 years were not trusted by Swedish authorities. To handle the situation, the Swedish national board of forensic medicine (Rättsmedicinalverket, RMV) was assigned by the government to create a centralized system for medical age assessments. RMV introduced a procedure including two biological age indicators; x-ray of the third molars and magnetic resonance imaging of the distal femoral epiphysis. In 2017, a total of 9617 males and 337 females were subjected to this procedure. No validation study for the procedure was however published, and the observed number of cases with different maturity combinations in teeth and femur were unexpected given the claims originally made by RMV. We present a general stochastic model enabling us to study which combinations of age indicator model parameters and age population profiles are consistent with the observed 2017 data for males. We find that, contrary to some RMV claims, maturity of the femur, as observed by RMV, appears on average well before maturity of teeth. According to our estimates, approximately 15% of the tested males were children. These children had an approximate 33% risk of being classified as adults. The corresponding risk for an adult to be misclassified as a child was approximately 7%. We determine uncertainties and ranges of estimates under reasonable perturbations of the prior.

Epigenetic Age in Male Combat-Exposed War Veterans: Associations with Posttraumatic Stress Disorder Status

DNA methylation patterns change with age and can be used to derive an estimate of “epigenetic age,” an indicator of biological age. Several studies have shown associations of posttraumatic stress disorder (PTSD) with worse somatic health and early mortality, raising the possibility of accelerated biological aging. This study examined associations between estimated epigenetic age and various variables in 160 male combat-exposed war veterans with (n = 79) and without PTSD (n = 81). DNA methylation was assessed in leukocyte genomic DNA using the Illumina 450K DNA methylation arrays. Epigenetic age was estimated using Horvath’s epigenetic clock algorithm and Δage (epigenetic age-chronological age) was calculated. In veterans with PTSD (Δage = 3.2), Δage was on average lower compared to those without PTSD (Δage = 5.0; p = 0.02; Cohen’s d = 0.42). This between-group difference was not explained by race/ethnicity, lifestyle factors or childhood trauma. Antidepressant use, however, explained part of the association. In the PTSD positive group, telomerase activity was negatively related to Δage (β = –0.35; p = 0.007). In conclusion, veterans with PTSD had significantly lower epigenetic age profiles than those without PTSD. Further, current antidepressant use and higher telomerase activity were related to relatively less epigenetic aging in veterans with PTSD, speculative of a mechanistic pathway that might attenuate biological aging-related processes in the context of PTSD.

Age-related gene expression profiles of immature human oocytes.

What is the difference between the gene expression profiles of single human germinal vesicle (GV) oocytes from women of different ages? There were no statistically significant differences in gene expression profiles of human GV oocytes from women of different ages (range: 25-43). It is well established that reproductive capacity declines as women age, which is attributed to oocyte quality since this decline is counterbalanced in older women receiving young donor oocytes. Altered gene expression of human oocytes at different stages of development in relation to female age is one of the suggested mechanisms that could explain the decrease in oocyte quality. Between 2012 and 2014, 40 human GV oocytes of 40 women were obtained during follicular aspiration as part of routine ICSI treatment. Gene expression profiles of 38 GV oocytes were determined in four different age groups: 25-30, 31-35, 36-38 and 39-43 years of age. GV oocytes were donated for research and frozen between 3.5 and 7.5 h after follicular aspiration. Subsequently, GV oocytes were thawed and prepared for gene expression profile analysis using Agilent microarrays containing ~42 000 Human Gene Expression probe-sets. Gene expression profiles were visualized by hierarchical clustering and the top 500 most differing genes were determined by multidimensional scaling (MDS). Transcripts were analysed in a class comparison between the four age groups and for indicators of biological age: antral follicle count (AFC) and the total dosage of FSH needed for ovarian stimulation. Individual transcripts were analysed using linear regression. A false discovery rate <0.05 was considered statistically significant. Visualization of gene expression profiles of GV oocytes with hierarchal clustering and MDS demonstrated no clear grouping of samples based on female age, AFC or FSH dosage. The gene expression profile of GV oocytes classified in four age groups revealed no significantly differentially expressed genes between the four different age groups. There were also no significantly differentially expressed genes in the linear regression analysis for individual transcripts against age. Not applicable. Immature (GV) oocytes obtained from ovarian stimulation cycles were used. Findings may therefore differ for oocytes at other developmental stages and for in-vivo matured oocytes under physiological conditions. Due to our relatively large, but still limited study sample (40 GV oocytes), we cannot exclude that there might be smaller age-related gene-expression differences, i.e. due to a lack of power. We did not find an effect of female age on gene expression profiles of individual human GV oocytes. Other studies have suggested that gene-expression profiles are affected in mature oocytes, which might imply that female age affects oocyte maturation. Alternatively, other mechanisms in human oocytes might cause the age-related fertility decline. This study received no external funding and there are no competing interests.

DNA methylation associated with healthy aging of elderly twins.

Variation in healthy aging and lifespan is ascribed more to various non-genetic factors than to inherited genetic determinants, and a major goal in aging research is to reveal the epigenetic basis of aging. One approach to this goal is to find genomic sites or regions where DNA methylation correlates with biological age. Using health data from 134 elderly twins, we calculated a frailty index as a quantitative indicator of biological age, and by applying the Infinium HumanMethylation450K BeadChip technology to their leukocyte DNA samples, we obtained quantitative DNA methylation data on genome-wide CpG sites. We analyzed the health and epigenome data by taking two independent associative approaches: the parametric regression-based approach and a non-parametric machine learning approach followed by GO ontology analysis. Our results indicate that DNA methylation at CpG sites in the promoter region of PCDHGA3 is associated with biological age. PCDHGA3 belongs to clustered protocadherin genes, which are all located in a single locus on chromosome 5 in human. Previous studies of the clustered protocadherin genes showed that (1) DNA methylation is associated with age or age-related phenotypes; (2) DNA methylation can modulate gene expression; (3) dysregulated gene expression is associated with various pathologies; and (4) DNA methylation patterns at this locus are associated with adverse lifetime experiences. All these observations suggest that DNA methylation at the clustered protocadherin genes, including PCDHGA3, is a key mediator of healthy aging.

It's more than skin-deep: The relationship between social victimization and telomere length in adolescence.

This study examined the relationship between peer victimization and telomere length (TL), an indicator of biological aging that is associated with stressors (Epel, 2009). It was predicted that social victimization would have a greater impact upon TL, as well as the frequency and severity of health complaints than physical victimization. Adolescents (Mage = 15.91 years, SDage = 1.65) and their parents completed measures of peer victimization and physical health problems; adolescents also submitted a DNA sample for telomere analysis. Greater instances of being socially, but not physically, victimized were associated with shorter telomeres, as well as more frequent and severe health complaints. TL was also negatively related to both the frequency and severity of health problems, even after controlling for BMI, age, and sex of participant. The relationship between social victimization and health complaints via TL held only at higher levels of social victimization. These findings are the first to find an association between peer victimization and shortened telomeres.

Faster ticking rate of the epigenetic clock is associated with faster pubertal development in girls

ABSTRACTEpigenetic age is an indicator of biological aging, capturing the impact of environmental and behavioral influences across time on cellular function. Deviance between epigenetic age and chronological age (AgeAccel) is a predictor of health. Pubertal timing has similarly been associated with cancer risk and mortality rate among females. We examined the association between AgeAccel and pubertal timing and adolescent breast composition in the longitudinal Growth and Obesity Cohort Study. AgeAccel was estimated in whole blood using the Horvath method at breast Tanner 2 (B2) and 4 (B4). Total breast volume, absolute fibro-glandular volume (FGV), and %FGV were evaluated at B4 using dual X-ray absorptiometry. The impact of AgeAccel (mean: 0; SD: 3.78) across puberty on the time to breast development (thelarche), menarche, and pubertal tempo (thelarche to menarche) was estimated using accelerated failure time models; generalized estimating equations were used to evaluate associations with breast density. A five-year increase in average adolescent AgeAccel was associated with a significant decrease in time to menarche [hazard ratio (HR): 1.37; 95% confidence interval (CI): 1.04, 1.80] adjusting for birth weight, maternal pre-pregnancy body mass index, maternal height, maternal education, B2 height, fat percentage, and cell composition. AgeAccel displayed a stronger inverse association with pubertal tempo (HR: 1.48; 95% CI: 1.10, 1.99). A five-year increase in AgeAccel was associated with 5% greater %FGV, adjusting for B4 percent body fat, and maternal traits (95% CI: 1.01, 1.10). Our study provides unique insight into the influence of AgeAccel on pubertal development in girls, which may have implications for adult health.

Significant SNPs Related to Telomere Length and Hepatocellular Carcinoma Risk in Chronic Hepatitis B Carriers

Chronic hepatitis B virus (HBV) infection increases the risk of developing cirrhosis and hepatocellular carcinoma (HCC) with suspected interactions between virus replication and host immune responses. A number of reports have suggested that telomerase function may be involved in chronic hepatitis B (CHB) pathogenesis, but positive or negative associations with HCC risk remain for discussion. Mean telomere length is an indicator of biological aging and it has been reported that reduction in NBV carriers compared to normal individuals. In somatic cells, telomeres contain simple, tandemly repeated G-rich sequences that frequently are reduced by 50 to 200 base pairs at each cell division. Several genome-wide association studies (GWAS) in diverse ethnic populations have revealed eleven single nucleotide polymorphisms (SNPs) linked to telomere length. Two of these, rs398652 and rs621559, have prognostic value and could be used as genetic markers. This review describes current knowledge concerning telomerase activity and telomere length as well as significant polymorphisms in HBV-related HCC patients. In particular, to cast light on genotype-phenotype interactions, we used SNPnexus to evaluate effects of the two SNPs on risk of disease and complex disorders.

Assessment of Leukocyte Telomere Length as an Indicator of Biological Age for Risk Stratification of Cardiovascular Events: A Meta-Analysis

Background: Chronological age is the most common risk factor for atrial fibrillation (AF). Telomere length is a marker of biological age. The association between biological age and AF, AF risk factors, and cardiovascular events is not well established.

Childhood adversity, social support, and telomere length among perinatal women

Adverse perinatal health outcomes are heightened among women with psychosocial risk factors, including childhood adversity and a lack of social support. Biological aging could be one pathway by which such outcomes occur. However, data examining links between psychosocial factors and indicators of biological aging among perinatal women are limited. The current study examined the associations of childhood socioeconomic status (SES), childhood trauma, and current social support with telomere length in peripheral blood mononuclear cells (PBMCs) in a sample of 81 women assessed in early, mid, and late pregnancy as well as 7–11 weeks postpartum. Childhood SES was defined as perceived childhood social class and parental educational attainment. Measures included the Childhood Trauma Questionnaire, Center for Epidemiologic Studies-Depression Scale, Multidimensional Scale of Perceived Social Support, and average telomere length in PBMCs. Per a linear mixed model, telomere length did not change across pregnancy and postpartum visits; thus, subsequent analyses defined telomere length as the average across all available timepoints. ANCOVAs showed group differences by perceived childhood social class, maternal and paternal educational attainment, and current family social support, with lower values corresponding with shorter telomeres, after adjustment for possible confounds. No effects of childhood trauma or social support from significant others or friends on telomere length were observed. Findings demonstrate that while current SES was not related to telomeres, low childhood SES, independent of current SES, and low family social support were distinct risk factors for cellular aging in women. These data have relevance for understanding potential mechanisms by which early life deprivation of socioeconomic and relationship resources affect maternal health. In turn, this has potential significance for intergenerational transmission of telomere length. The predictive value of markers of biological versus chronological age on birth outcomes warrants investigation.

Mammographic density, blood telomere length and lipid peroxidation

Extensive mammographic density is a strong risk factor for breast cancer, but may also be an indicator of biological age. In this study we examined whether mammographic density is related to blood telomere length, a potential marker of susceptibility to age-related disease. We measured mammographic density by a computer assisted method and blood telomere length using a validated PCR method. Urinary malondialdehyde (MDA), a marker of lipid peroxidation, was measured in 24 hour urine collections. In the 342 women examined telomere length was negatively correlated with age, was lower in postmenopausal compared to premenopausal women and in smokers compared to non-smokers, and was positively correlated with urinary MDA. Telomere length was not associated with percent mammographic density or dense area, before or after adjustment for risk factors and MDA. However, there was a significant interaction between telomere length and MDA in their association with mammographic density. At lower levels of MDA, mammographic density and telomere length were inversely associated; while at high levels of MDA, there was evidence of a J-shaped association between mammographic density and telomere length. Further work is need to replicate these results and to examine the association of mammographic density with age-related chronic disease and mortality.

Preterm infants have significantly longer telomeres than their term born counterparts.

There are well-established morbidities associated with preterm birth including respiratory, neurocognitive and developmental disorders. However several others have recently emerged that characterise an ‘aged’ phenotype in the preterm infant by term-equivalent age. These include hypertension, insulin resistance and altered body fat distribution. Evidence shows that these morbidities persist into adult life, posing a significant public health concern. In this study, we measured relative telomere length in leukocytes as an indicator of biological ageing in 25 preterm infants at term equivalent age. Comparing our measurements with those from 22 preterm infants sampled at birth and from 31 term-born infants, we tested the hypothesis that by term equivalent age, preterm infants have significantly shorter telomeres (thus suggesting that they are prematurely aged). Our results demonstrate that relative telomere length is highly variable in newborn infants and is significantly negatively correlated with gestational age and birth weight in preterm infants. Further, longitudinal assessment in preterm infants who had telomere length measurements available at both birth and term age (n = 5) suggests that telomere attrition rate is negatively correlated with increasing gestational age. Contrary to our initial hypothesis however, relative telomere length was significantly shortest in the term born control group compared to both preterm groups and longest in the preterm at birth group. In addition, telomere lengths were not significantly different between preterm infants sampled at birth and those sampled at term equivalent age. These results indicate that other, as yet undetermined, factors may influence telomere length in the preterm born infant and raise the intriguing hypothesis that as preterm gestation declines, telomere attrition rate increases.

Influence of Yoga means on students’ biological age indicators

Purpose: to determine effectiveness of Yoga means’ implementation in students’ physical education programs. Material: in experiment 85 2nd year students participated, who were divided in control group (CG, n=43, 15 boys and 28 girls) and experimental group (EG, n=42, 17 boys and 25 girls). Their calendar age was 18-19 years. By state of health all students were in main health group (without health problems). The researches were carried out during one academic semester and implied finding and comparing of students’ biological age. Results: by results of medical examination we registered 22 years as minimal biological age and 55 years as maximal. We found no students, whose biological age would correspond to calendar age. It was also found that systemic practicing of Yoga permits to keep proper level of students’ health and increase their interest to physical exercises’ practicing. It was proved that application of Yoga means approached students’ biological age to calendar one. Conclusions: introduction of Yoga complexes in physical education program will permit to sustain and improve students’ biological indicators and positively influence on their health.

Abstract P080: Self-reported Experiences of Everyday Discrimination are Associated With Shorter Leukocyte Telomeres in African-American Women With Coronary Heart Disease

Rationale: Leukocyte telomere length (LTL) is an indicator of biological aging. Telomere shortening may be sensitive to social stressors such as discrimination, but this has not been previously examined in a biracial cohort of patients with coronary heart disease (CHD). Objective: To explore differences in LTL by race and gender and examine whether discrimination was associated with accelerated cellular aging (shorter telomere length). Methods: Data were from 367 White and African American patients in the Mental Stress Ischemia Mechanisms and Prognosis Study (MIPS) which enrolled patients with a diagnosis of stable CHD from Emory University-affiliated hospitals and clinics. LTL was measured by quantitative polymerase chain reaction (qPCR) and expressed as a ratio of the amount of telomeric DNA to the amount of single-copy control gene (T/S). The T/S ratios were then converted to kilobase pairs. Discrimination was measured using the 10-item Everyday Discrimination Scale (EDS), where participants reported their experiences of everyday mistreatment during the previous 12 months. Responses were rated using 4-point Likert scales ranging from never = 1 to often = 4 which were summed. Due to the potential batch effect in telomere length, we modeled telomere plate as a random effect. Multiple linear regression models were stratified by race/ethnicity and gender to estimate differences in mean LTL and associations with discrimination, adjusted for potential confounding factors. Results: African American women had longer mean LTL (5.58; SD: 0.05) compared to African American men (5.28; SD: 0.04), White women (5.22; SD: 0.05) and White men (5.24; SD: 0.03). Reports of discrimination were higher among African American men (16.1; SD: 6.5) compared to African American women (15.4; SD: 4.9), White women (14.9; SD: 4.4), and White men (13.5; SD: 3.8). The association between discrimination and accelerated cellular aging was statistically significant among African American women [β = -0.02; 95% CI: (-0.04, -0.001); p=0.0377] after models were adjusted for demographics, smoking history, BMI, and disease history. Discrimination was not significantly associated with accelerated cellular aging among African American men [β = -0.01; 95% CI: (-0.02, 0.01)], White men β = [-0.003; 95% CI: (-0.02, 0.01)], or White women [β = -0.01; 95% CI: (-0.03, 0.01)]. The association between discrimination and accelerated cellular aging remained statistically significant for African American women after further adjusting for depression and perceived stress. Conclusions: Although African American women with CHD have longer telomere length, they may experience greater telomere shortening in relation to discrimination. Accelerated telomere shortening secondary to discrimination stress may be a potential mechanism of health related disparities among African American women with CHD.

Physical frailty and sarcopenia (PF&S): a point of view from the industry.

We have observed over the last 15years a wide debate both in the medical scientific community and in the public health arena on the definition and operationalization of frailty, typically a geriatric condition, and in particular of physical frailty linked to sarcopenia. Because physical frailty in its initial phase can still be reversed, fighting sarcopenia in elderly persons has the potential to slow or halt progressive decline towards disability and dependency. Quite recently, regulators focused attention on frailty as an indicator of biological age to be measured to characterize elderly patients before their inclusion in clinical trials. A European guidance regarding most adapted evaluation instruments of frailty is currently under public consultation. Does the regulatory initiative imply we should now consider frailty, and particularly physical frailty, primarily as an important risk factor for adverse events and poor response, or mainly as a clinical tool helping the physician to opt for one therapeutic pathway or another? Or is physical frailty above all a specific geriatric condition deserving an effective and innovative therapeutic approach with the objective to curb the incidence of its most common result, e.g., mobility disability? Pharmaceutical industry developers consider both faces of the coin very relevant. We agree with regulators that better characterization of subpopulations, not only in elderly patients, can improve the benefit risk ratio of medicines. At the same time, we believe it is in the public health interest to develop novel drugs indicated for specific geriatric conditions, like osteoporosis in the 1990s and sarcopenia today. We consider it an important therapeutic goal to effectively delay mobility disability and to extend the active, independent, and healthy life years of aging people. The "Sarcopenia and Physical fRailty IN older people: multi-componenT Treatment strategies" (SPRINTT) collaborative project under IMI is paving the way for adapted methodologies to study the change of physical frailty and sarcopenia in at-risk older persons and to adequately characterize the population that needs to be treated.

The frailty index outperforms DNA methylation age and its derivatives as an indicator of biological age

The measurement of biological age as opposed to chronological age is important to allow the study of factors that are responsible for the heterogeneity in the decline in health and function ability among individuals during aging. Various measures of biological aging have been proposed. Frailty indices based on health deficits in diverse body systems have been well studied, and we have documented the use of a frailty index (FI34) composed of 34 health items, for measuring biological age. A different approach is based on leukocyte DNA methylation. It has been termed DNA methylation age, and derivatives of this metric called age acceleration difference and age acceleration residual have also been employed. Any useful measure of biological age must predict survival better than chronological age does. Meta-analyses indicate that age acceleration difference and age acceleration residual are significant predictors of mortality, qualifying them as indicators of biological age. In this article, we compared the measures based on DNA methylation with FI34. Using a well-studied cohort, we assessed the efficiency of these measures side by side in predicting mortality. In the presence of chronological age as a covariate, FI34 was a significant predictor of mortality, whereas none of the DNA methylation age-based metrics were. The outperformance of FI34 over DNA methylation age measures was apparent when FI34 and each of the DNA methylation age measures were used together as explanatory variables, along with chronological age: FI34 remained significant but the DNA methylation measures did not. These results indicate that FI34 is a robust predictor of biological age, while these DNA methylation measures are largely a statistical reflection of the passage of chronological time.

Comparative analysis of different geroprotective methods

One hundred and ten patients of different ages have undergone a comparative analysis of the efficiency and safety of a number of geroprotective techniques, including the use of dry lead-carbonate baths, hyperbaric oxygenation, therapeutic massage, and reception of oligopeptide preparations containing complexes of lysyl-glutamyl-asparagin and glutamyl-asparagin-arginine complexes (Vezugen and Pinealon). The most pronounced positive impact on indicators of biological age was found during the combined use of these two oligopeptide complexes. The safest ones in terms of influence on a number of biochemical and immunological parameters and on the clinical state of patients were medical massage and oligopeptide preparations. The use of dry carbon dioxide baths and hyperbaric oxygenation, while having an undoubtedly positive influence on the indices of biological age, has a number of limitations and counterindications.

Hostility and telomere shortening among U.S. military veterans: Results from the National Health and Resilience in Veterans Study

Chronic disorders of aging are critical concerns for the U.S. veteran population, which is, on average, two decades older than the non-veteran population. Characterization of risk factors that may accelerate biological aging is important in identifying targets for prevention and intervention. In the current study, we analyzed data from a contemporary, and nationally representative sample of U.S. veterans to evaluate the relationship between a broad range of sociodemographic, military, and clinical variables, and peripheral telomere length, which is an indicator of biological age and linked to risk for aging-related disorders and mortality. Data from 468U.S. military veterans who participated in the National Health and Resilience in Veterans Study were analyzed. Telomere length was assessed from cells isolated from saliva using quantitative polymerase chain reaction methods. A multivariable binary logistic regression analysis was conducted to evaluate the relations between hostility and telomere length, while controlling for sociodemographic, military, and clinical variables. Greater scores on a measure of hostility were independently associated with telomere shortening, even after adjustment for a broad range of other variables (odds ratio [OR]=1.58, 95% confidence interval [CI]=1.15–2.18). Secondary analyses revealed that this association was driven by difficulties controlling anger (OR=1.72, 95%CI=1.14–2.61), which reflect the external manifestation of hostility, rather than aggressive urges or impulses. Hostility, particularly difficulties controlling anger, is associated with peripheral telomere shortening in U.S. military veterans. Prevention and treatment efforts designed to reduce hostility may help mitigate risk for accelerated cellular aging in this growing segment of the U.S. population.

The Influence of Biological Age on Muscle Morphology in Youth Judo Athletes

PURPOSE: Biological age and chronological age (CA) are both used when assessing maturation status in children and adolescents. Muscular development is influenced by puberty and somatic maturity, an indicator of biological age, which can be estimated by the age at peak height velocity (PHV). However, it is unclear whether muscle morphology is influenced more by biological or chronological age in young judo athletes. METHODS: Anthropometric data [weight (BW) and standing and seated height] were collected from thirty-three youth judo athletes [males: n=23, females: n=10; CA: 12.9±2.7y; experience (EXP): 5.5±2.9y] to predict years from PHV and reported as maturity offset (MO: −0.6±2.2y). Muscle morphology [cross-sectional area (CSA), thickness (MT), pennation angle (PA), fascicle length (FL), and echo-intensity (EI)] of the dominant and non-dominant vastus lateralis (VL) was assessed via ultrasonography. The average of both legs was calculated for each morphological measure. Data were examined using stepwise regression to determine if CA, MO, or EXP were predictive of muscle morphology. Partial correlations were used to determine relationships among the identified predictive measures and muscle morphology. RESULTS: MO was shown to be the best predictor (p<0.001) of CSA (R2=0.748, SEE=3.807), and MT (R2=0.535, SEE=0.220), while CA was shown to be the best predictor (p<0.001) of FL (R2=0.602, SEE=0.665). CA was the best predictor of EI (R2=0.287, SEE=14.055, p=0.004), while the inclusion of EXP increased the predictive ability of the model by 23.5% (R2=0.522, SEE=11.741, p<0.001). None of the selected variables were predictive of PA. After accounting for BW, significant relationships were observed between MO and CSA (r=0.394, p=0.047), EI (r=−0.409, p=0.038), and FL (r=0.461, p=0.018); between EXP and EI (r=0.436, p=0.026); and between CA and EI (r=−0.574, p=0.002) and FL (r=0.504, p=0.009). CONCLUSION: Biological age (i.e., maturity offset) appears to be indicative of lower body muscle size, whereas chronological age, and potentially years of experience, appears to be more indicative of lower body muscle composition among youth judo athletes. However, in this cross-sectional sample, ultrasound-derived pennation angle did not appear to be related to age, maturation status, or years of experience.