Childhood Physical and Sexual Abuse History and Leukocyte Telomere Length among Women in Middle Adulthood

The role of optimism, connectedness, and neighborhood collective efficacy as moderators of harsh parenting on telomere length

Research to date has examined telomere length in relation to adverse childhood events but few studies have examined whether protective factors act as a buffer to offset this effect. Further, research is lacking examining whether protective factors vary among minoritized youth. Data were from the Future Families and Child Wellbeing Study, a stratified, multistage sample of 4898 children born in large U.S. cities between 1998 and 2000. Births to unmarried mothers were oversampled by a 3-1 ratio, which resulted in the inclusion of a multi-ethnic and economically diverse sample (48 % Black; 27 % Hispanic; 21 % White; 4 % other racial and ethnic minorities). The current study examined optimism, social connectedness, and neighborhood collective efficacy at age 15 as potential protective factors against the effects of harsh parenting on telomere length in adolescence (analytic N = 1168 youth). This study examines cumulative exposure to harsh parenting across childhood (ages 3, 5, and 9 years). Results from analyses stratified by race/ethnicity show optimism, connectedness, and neighborhood collective efficacy serve as protective factors; however, unique protective factors emerged among different racial and ethnic youth suggesting the need to examine context-specific protective factors. Implications of these findings provide evidence for considering intersectionality in terms of protective factors for biomarkers among minoritized youth.

Telomere Erosion and Depressive Symptoms Across Development Following Institutional Care

OBJECTIVE

A large literature has identified exposure to early caregiving adversities as a potent risk for developing affective psychopathology, with depression, in particular, increasing across childhood into adolescence. Evidence suggests telomere erosion, a marker of biological aging, may underlie associations between adverse early-life experiences and later depressive behavior; yet, little is understood about this association during development.

METHOD

The current accelerated longitudinal study examined concurrent telomere length and depressive symptoms concurrently, 2 and 4 years later, from the preschool period through adolescence among children exposed (n =116) and not exposed (n = 242) to early previous institutional (PI) care.

RESULTS

PI care was associated with shorter telomeres on average and with quadratic age-related growth in depressive symptoms, indicating a steeper association between PI care and depressive symptoms in younger age groups that leveled off in adolescence. Contrary to studies in adult samples, telomere length was not associated with depressive symptoms, and it did not predict future symptoms.

CONCLUSION

These findings indicate that early caregiving disruptions increase the risk for both accelerated biological aging and depressive symptoms, although these variables did not correlate with each other during this age range.

Child maltreatment and telomere length in middle and older age: retrospective cohort study of 141 748 UK Biobank participants

BACKGROUND

There is evidence that child maltreatment is associated with shorter telomere length in early life.

AIMS

This study aims to examine if child maltreatment is associated with telomere length in middle- and older-age adults.

METHOD

This was a retrospective cohort study of 141 748 UK Biobank participants aged 37-73 years at recruitment. Leukocyte telomere length was measured with quantitative polymerase chain reaction, and log-transformed and scaled to have unit standard deviation. Child maltreatment was recalled by participants. Linear regression was used to analyse the association.

RESULTS

After adjusting for sociodemographic characteristics, participants with three or more types of maltreatment presented with the shortest telomere lengths (β = -0.05, 95% CI -0.07 to -0.03; P < 0.0001), followed by those with two types of maltreatment (β = -0.02, 95% CI -0.04 to 0.00; P = 0.02), referent to those who had none. When adjusted for depression and post-traumatic stress disorder, the telomere lengths of participants with three or more types of maltreatment were still shorter (β = -0.04, 95% CI -0.07 to -0.02; P = 0.0008). The telomere lengths of those with one type of maltreatment were not significantly different from those who had none. When mutually adjusted, physical abuse (β = -0.05, 95% CI -0.07 to -0.03; P < 0.0001) and sexual abuse (β = -0.02, 95% CI -0.04 to 0.00; P = 0.02) were independently associated with shorter telomere length.

CONCLUSIONS

Our findings showed that child maltreatment is associated with shorter telomere length in middle- and older-aged adults, independent of sociodemographic and mental health factors.

Posttraumatic Stress Disorder, Depression, and Accelerated Aging: Leukocyte Telomere Length in the Nurses' Health Study II

Background

Exposure to trauma, posttraumatic stress disorder (PTSD), and depression have been independently associated with leukocyte telomere length (LTL), a cellular marker of aging associated with mortality and age-related diseases. However, the joint contributions of trauma and its psychological sequelae on LTL have not been examined.

Methods

We conducted an analysis of LTL in a subset of women from the Nurses' Health Study II (N = 1868). Lifetime exposure to traumatic events, PTSD, and depression was assessed with validated measures. DNA was extracted from peripheral blood leukocytes and telomere repeat copy number to single gene copy number was determined by quantitative real-time polymerase chain reaction telomere assay. Linear regression models assessed the association of trauma, PTSD, and depression with LTL after adjustment for health behaviors and medical conditions.

Results

Trauma, PTSD, and depression were not independently associated with LTL in mutually adjusted models. However, individuals with severe psychological distress-characterized by comorbid PTSD and depression-had shorter LTL equivalent to being 7.62 years older (95% CI, 0.02 to 17.97) than participants who had never experienced a traumatic event and were not depressed. Further examination found only an association among individuals with the highest number of PTSD symptoms and comorbid depression equivalent to 9.71 additional years of aging (95% CI, 1.36 to 20.49). No effect was found among individuals meeting the minimum threshold for probable PTSD with comorbid depression.

Conclusions

Severe psychological distress, as indicated by the presence of comorbid PTSD and depression, may be associated with shorter LTL.

Mechanisms by which adverse childhood experiences, other traumas and PTSD influence the health and well-being of individuals with eating disorders throughout the life span

BACKGROUND

Multiple published sources from around the world have confirmed an association between an array of adverse childhood experiences (ACEs) and other traumatic events with eating disorders (EDs) and related adverse outcomes, including higher morbidity and mortality.

METHODS

In keeping with this Special Issue's goals, this narrative review focuses on the ACEs pyramid and its purported mechanisms through which child maltreatment and other forms of violence toward human beings influence the health and well-being of individuals who develop EDs throughout the life span. Relevant literature on posttraumatic stress disorder (PTSD) is highlighted when applicable.

RESULTS

At every level of the pyramid, it is shown that EDs interact with each of these proclaimed escalating mechanisms in a bidirectional manner that contributes to the predisposition, precipitation and perpetuation of EDs and related medical and psychiatric comorbidities, which then predispose to early death. The levels and their interactions that are discussed include the contribution of generational embodiment (genetics) and historical trauma (epigenetics), social conditions and local context, the ACEs and other traumas themselves, the resultant disrupted neurodevelopment, subsequent social, emotional and cognitive impairment, the adoption of health risk behaviors, and the development of disease, disability and social problems, all resulting in premature mortality by means of fatal complications and/or suicide.

CONCLUSIONS

The implications of these cascading, evolving, and intertwined perspectives have important implications for the assessment and treatment of EDs using trauma-informed care and trauma-focused integrated treatment approaches. This overview offers multiple opportunities at every level for the palliation and prevention of EDs and other associated trauma-related conditions, including PTSD.

Early life trauma and adult leucocyte telomere length

BACKGROUND

Telomere length, a biomarker of cell division and cellular aging, has been associated with multiple chronic disease endpoints. Experienced trauma over the life course may contribute to telomere shortening via mechanisms of stress embodiment. However, it is unclear how patterns of co-occurring trauma during sensitive periods (e.g., early life) throughout the life course may influence telomere shortening. We examine the relationship between co-occurring early life trauma on adult telomere length and the extent to which adulthood trauma, socioeconomic position, and health and lifestyle factors may mediate this relationship.

METHODS

We use data from a sample of participants in the Sister Study (N = 740, analytic sample: n = 602), a prospective cohort of U.S. self-identified females aged 35-74 years at enrollment (2003-2009) for whom leukocyte telomere length was measured in baseline blood samples. Participants reported their experience of 20 different types of trauma, from which we identified patterns of co-occurring early life trauma (before age 18) using latent class analysis. We estimated the direct and indirect effects of early life trauma on leukocyte telomere length using structural equation modeling, allowing for mediating adult pathways.

RESULTS

Approximately 47 % of participants reported early life trauma. High early life trauma was associated with shorter telomere length compared to low early life trauma (β = -0.11; 95 % CI: -0.22, -0.004) after adjusting for age and childhood socioeconomic position. The inverse association between early life trauma and adult leukocyte telomere length was largely attributable to the direct effect of early life trauma on telomere length (β = -0.12; 95 %CI: -0.23, -0.01). Mediating indirect pathways via adult trauma, socioeconomic position, and health metrics did not substantively contribute the overall association.

CONCLUSIONS

These findings highlight the role of patterns of co-occurring early life trauma on shortened telomere length independent of adult pathways.

Association between Childhood Exposure to Family Violence and Telomere Length: A Meta-Analysis

The aims of this meta-analysis were to examine the association between childhood exposure to family violence and telomere length and the moderating variables that influence this association. Relevant works published on or before 1st September 2022 were identified through a search in five major databases in English and 19 articles (N = 18,977) finally met the inclusion criteria. A meta-analysis was conducted to compute the pooled effect size (correlation; r), and moderator analyses were performed using a random effects meta-analytic model. The studies yielded a significant inverse association between childhood exposure to family violence and telomere length, with a small effect size (r = -0.038, 95% CI [-0.070, -0.005], p = 0.025). Furthermore, the strength of this association was stronger in studies examining the co-occurrence of multiple types of violence than in those examining just one type (Q = 8.143, p = 0.004). These findings suggested that victims' telomere length may be negatively influenced by childhood exposure to family violence and that such impairment appears to be stronger for those who are exposed to multiple types of violence. Future studies are necessary to examine the moderating and mediating factors underlying the association between childhood exposure to family violence and telomere length.

A Systematic Review of Research on Trauma and Women's Health in the Nurses' Health Study II

OBJECTIVE

To synthesize research on interpersonal trauma and women's health from the Nurses' Health Study II (NHS II) and to analyze conceptualization of interpersonal trauma across studies.

DATA SOURCES

A literature review was conducted in PubMed using a systematic search strategy.

STUDY SELECTION

Articles were included in the review if they used data from the NHS II and involved investigations of interpersonal trauma. Theoretical articles, methodologic articles, and other literature reviews involving the NHS II were excluded. Initially, the search returned 61 articles. After exclusions, 45 articles met the criteria for inclusion in the review and data extraction.

DATA EXTRACTION

Information was extracted and consolidated in an evidence table. Data included study time frame, sample, definition of trauma, outcomes studied, and journal of publication.

DATA SYNTHESIS

Trauma was not operationalized consistently across studies, even though the NHS II assessed trauma experiences in childhood, adolescence, and adulthood. Most investigations focused on childhood abuse, with investigations of childhood sexual abuse overrepresented in comparison to other abuse experiences. Authors conducting studies of trauma at any time in the life course consistently found a negative association with physical and mental health outcomes, which were increased by the presence of posttraumatic stress symptoms. Results from a small number of studies suggested a negative intergenerational impact of trauma on the children of women in the NHS II.

CONCLUSION

Interpersonal trauma across the life course was strongly associated with many leading causes of morbidity and mortality among female nurses. Trauma conceptualization and operationalization varied across studies, and future investigations should leverage the full range of trauma measures available in the NHS II data set.

Psychobiological Consequences of Childhood Sexual Abuse: Current Knowledge and Clinical Implications

A large body of research has documented the long-term harms of childhood sexual abuse (CSA) on an individual’s emotional-adaptive function and mental health. Recent studies have also provided evidence of the biological impact of CSA, implicating specific alterations in many systems, including the endocrine and immune systems, and in DNA and chromatin, in the pathogenesis of medical disorders. Although the effects of CSA are often examined with regard to the general impact of early-life traumatic experiences, the study of CSA per sè, as a trigger of specific pathogenic pathways, would be more appropriate to understand their long-term implications and develop tailored diagnostic and therapeutic strategies. Based on these premises, this narrative minireview summarizes the research on the short-term and long-term sequelae of CSA, focusing on dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis, the effects on the immune system, and the changes to DNA through altered methylation. Also, we discuss the literature that examines dysfunctional DNA telomere erosion and oxidative stress markers as a sign of CSA. Finally, recent evidence of the intergenerational transmission of the effects of CSA is reported. The impact of CSA on brain connectivity and functions is out of the scope of this review, thus brain imaging studies are not included. The results of this minireview are discussed, considering their implications for prevention and clinical practice.

The dimensionality of adverse childhood experiences: A scoping review of ACE dimensions measurement

OBJECTIVE

Despite extensive research, the concept of adverse childhood experiences (ACEs) is not fully developed and there is low agreement on how the concept should be defined and measured. The purpose of this study was to 1) identify different conceptual dimensions associated with ACEs, such as timing or frequency; and 2) determine how these dimensions have been operationalized and analyzed to this point, in order to advance the conceptual understanding of ACEs.

METHODS

We conducted a scoping review of empirical journal articles on ACEs published after the original ACE-Study in 1998 to summarize the use of dimensions for the 10 conventional ACE domains. We used a PRISMA methodology to identify articles that assessed at least two of the 10 conventional ACE domains and at least two ACE dimensions. A standardized data extraction spreadsheet was used to record basic article information and specifics on ACE domains and dimensions.

RESULTS

Of 15,417 initial search results, 61 articles met all selection criteria. We identified four primary dimensions used for most ACE domains: frequency, timing, perception, and the role of the perpetrator. Additionally, we found several secondary and domain-specific dimensions, which relate to the intensity of the adverse event.

DISCUSSION

We identified the most commonly used ACE dimensions, but these lack standardized phrasing of items and response options. The inclusion of ACE dimensions may increase the accuracy of the association between ACEs and health outcomes and provide for more tailored treatment plans for people who have experienced ACEs. Future research should include a more comprehensive list of ACE domains and aim to develop a clearly articulated, standardized approach to assessing and analyzing ACE dimensions.

The Counterintuitive Relationship between Telomerase Activity and Childhood Emotional Abuse: Culture and Complexity

BACKGROUND: A burgeoning literature has found relationships between telomere length, telomerase activity, and human health and longevity. Although some research links a history of childhood adversity with shortened telomere length, our review found no prior research on the relationship between child maltreatment history and telomerase activity in adulthood. We hypothesized a negative relationship between child maltreatment and telomerase activity and hypothesized that the association would be moderated by sex. METHODS: These relationships were tested on a sample of 262 Hong Kong Chinese adults (200 females versus 62 males) with mild to moderate depression. RESULTS: Counterintuitively, emotional abuse was positively associated with telomerase activity, while other maltreatment types were non-significant. The positive relationship between emotional abuse and telomerase activity was significantly moderated by the sex of the participant. CONCLUSIONS: We advance two possible explanations for this finding (1) a culturally informed resilience explanation and (2) a homeostatic complexity explanation. The two explanations are not mutually exclusive. This trial is registered under Hong Kong Clinical Trial Register number HKCTR-1929. SIGNIFICANCE STATEMENT: Emotional abuse was significantly positively associated with telomerase activity. There are at least two non-mutually exclusive explanations for the findings. Simply put, either (1) in the cultural context of Hong Kong emotional abuse was not a risk factor, and/or (2) the conceptualization of telomerase activity as a straightforward indicator of longevity is overly simplistic. The first story we might term a “resilience explanation” while the second we might call a “homeostatic complexity” story.

Physical and sexual abuse in childhood and adolescence and leukocyte telomere length: A pooled analysis of the study on psychosocial stress, spirituality, and health

Introduction

We examined whether abuse in childhood and/or adolescence was associated with shorter telomere length in a pooled analysis of 3,232 participants from five diverse cohorts. We also assessed whether religion or spirituality (R/S) could buffer deleterious effects of abuse.

Methods

Physical and sexual abuse in childhood (age <12) and adolescence (age 12–18) was assessed using the Revised Conflict Tactics Scale and questions from a 1995 Gallup survey. We measured relative leukocyte telomere lengths (RTL) using quantitative real time polymerase chain reaction. We used generalized estimating equations to assess associations of physical and sexual abuse with log-transformed RTL z-scores. Analyses were conducted in each cohort, overall, and stratified by extent of religiosity or spirituality and religious coping in adulthood. We pooled study‐specific estimates using random‐effects models and assessed between-study heterogeneity.

Results

Compared to no abuse, severe sexual abuse was associated with lower RTL z-scores, in childhood: -15.6%, 95% CI: -25.9, -4.9; p-trend = 0.04; p-heterogeneity = 0.58 and in adolescence: -16.5%, 95% CI: -28.1, -3.0; p-trend = 0.08; p-heterogeneity = 0.68. Sexual abuse experienced in both childhood and adolescence was associated with 11.3% lower RTL z-scores after adjustment for childhood and demographic covariates (95% CI: -20.5%, -2.0%; p-trend = 0.03; p-heterogeneity = 0.62). There was no evidence of effect modification by R/S. Physical abuse was not associated with telomere length.

Conclusions

Sexual abuse in childhood or adolescence was associated with a marker of accelerated biological aging, decreased telomere length. The lack of moderation by R/S may be due to inability to capture the appropriate time period for those beliefs and practices.

Adverse childhood experiences, epigenetics and telomere length variation in childhood and beyond: a systematic review of the literature

A systematic review following PRISMA guidelines was conducted to answer the question: What epigenetic, telomeric and associated biological changes are associated with exposure to adverse childhood experiences (ACEs) in the under 12s? Using PRISMA guidelines, appropriate databases were searched. 190 papers were returned with 38 articles fully reviewed. Articles were each independently quality rated by two authors using the Crowe Critical Appraisal Tool and data were extracted. Of the 38 articles, 23 were rated as very high quality. Most study participants were adults (n = 7769) with n = 727 child participants. Only seven of the very/high-quality studies were prospective and involved children. Methylation was the most studied method of epigenetic modification. There is some evidence supporting epigenetic modification of certain markers in participants exposed to ACEs measured in adulthood. Research is lacking on non-coding aspects of the epigenome and on coding aspects other than DNA methylation. There is some evidence of a more powerful effect on telomere length if physical neglect was involved. Much further work is required to model biological and psychological effects of epigenetic changes during childhood using prospective study designs. The effect of ACEs on the cellular ageing process during childhood is inadequately investigated and relies solely on measure of telomere length. Future research suggestions are proposed.

Intergenerational transmission of childhood trauma? Testing cellular aging in mothers exposed to sexual abuse and their children

BACKGROUND

Exposure to maltreatment in childhood can lead to increased risk for poor health outcomes in adulthood. Child maltreatment and later poor health may be linked by premature biological aging. We tested whether childhood sexual abuse (CSA) was associated with telomere length (TL) in adult females. We further tested the hypothesis of intergenerational transmission of CSA-related effects by measuring TL in both CSA-exposed and non-exposed mothers and their children.

METHODS

Participants were a subset of females and their children in a prospective-longitudinal cohort study of sexually abused females and a demographically comparable control group from the same Washington, D.C. area. TL was measured using qPCR in both leukocyte and buccal samples from females (N = 108, mean age 36.3 years) and buccal samples from their children (N = 124, mean age 10.5 years). Multilevel models were used to test associations between CSA-exposure and TL measured in leukocytes and buccal tissue in females and to test the intergenerational effect of maternal-CSA exposure on age-adjusted TL in their children.

RESULTS

CSA-exposure was not associated with TL in adult females. Maternal TL and biological sex were significant predictors of child TL such that longer maternal TL predicted longer TL in children, and female children had longer TL than male children. However, maternal-CSA exposure did not predict TL in children.

DISCUSSION

CSA-exposure was not associated with TL in this cohort of middle-aged females, nor was there evidence for an intergenerational effect of maternal-CSA exposure on child TL. This finding is in line with some previous results on CSA and adult TL. Previous significant results associating child maltreatment with shorter TL may be capturing a population of individuals exposed to either multiple types of maltreatment compared to controls with no childhood adversity, or maltreatment in childhood with concurrent TL measurements.

Childhood maltreatment, behavioral adjustment, and molecular markers of cellular aging in preschool-aged children: A cohort study

OBJECTIVE

Childhood maltreatment is a major risk factor for the development of behavioral problems and poor physical and mental health. Accelerated cellular aging, through reduced telomere length and mitochondrial dysfunction, may be a mechanism underlying these associations.

METHODS

Families with (n = 133) and without (n = 123) child welfare documentation of moderate-severe maltreatment in the past six months participated in this study. Children ranged in age from 3 to 5 years, were racially and ethnically diverse, and 91% qualified for public assistance. Structured record review and interviews were used to assess a history of maltreatment and other adversities. Telomere length and mitochondrial DNA copy number (mtDNAcn) were measured from saliva DNA using real-time PCR. Measures were repeated at a six-month follow-up assessment. Repeated measures general linear models were used to examine the effects of maltreatment and other adversities on telomere length and mtDNAcn over time.

RESULTS

Maltreatment and other adverse experiences were significant positive predictors of both telomere length and mtDNAcn over time. Internalizing and externalizing behavior problems were also both significantly associated with telomere length, but only internalizing symptoms were associated with mtDNAcn.

CONCLUSIONS

This is the first study to show that mtDNAcn is altered in children with stress and trauma, and the findings are consistent with recent studies of adults. Surprisingly, children who experienced moderate-severe levels of maltreatment in the prior six months had longer telomeres, possibly reflecting compensatory changes in response to recent trauma. Telomere length and mtDNAcn were also associated with behavioral problems, suggesting that these measures of cellular aging may be causally implicated in the pathophysiology of stress-related conditions.

Translating basic research knowledge on the biological embedding of early-life stress into novel approaches for the developmental programming of lifelong health

This review integrates scientific knowledge obtained over the past few decades on the biological mechanisms that contribute to the profound association between exposure to early adversity, including childhood trauma and prenatal stress, and the lifelong elevated risk to develop a broad range of diseases. We further discuss insights into gene-environment interactions moderating the association between early adversity and disease manifestation and we discuss the role of epigenetic and other molecular processes in the biological embedding of early adversity. Based on these findings, we propose potential mechanisms that may contribute to the intergenerational transmission of risk related to early adversity from the mother to the fetus. Finally, we argue that basic research knowledge on the biological embedding of early adversity must now be translated into novel intervention strategies that are mechanism-driven and sensitive to developmental timing. Indeed, to date, there are no diagnostic biomarkers of risk or mechanism-informed interventions that we can offer to victims of early adversity in order to efficiently prevent or reverse adverse health outcomes. Such translational efforts can be expected to have significant impact on both clinical practice and the public health system, and will promote precision medicine in pediatrics and across the lifespan.

Adverse Childhood Experiences and Telomere Length a Look Into the Heterogeneity of Findings-A Narrative Review

Background: Adverse childhood experiences (ACEs) have been associated with poor mental and somatic health. Accumulating evidence indicates that accelerated biological aging-indexed by altered telomere-related markers-may contribute to associations between ACEs and negative long-term health outcomes. Telomeres are repeated, non-coding deoxyribonucleic acid (DNA) sequences at the end of chromosomes. Telomeres shorten during repeated cell divisions over time and are being used as a marker of biological aging. Objectives: The aim of the current paper is to review the literature on the relationship between ACEs and telomere length (TL), with a specific focus on how the heterogeneity of sample and ACEs characteristics lead to varying associations between ACEs and TL. Methods: Multiple databases were searched for relevant English peer-reviewed articles. Thirty-eight papers were found to be eligible for inclusion in the current review. Results: Overall, the studies indicated a negative association between ACEs and TL, although many papers presented mixed findings and about a quarter of eligible studies found no association. Studies with smaller sample sizes more often reported significant associations than studies with larger samples. Also, studies reporting on non-clinical and younger samples more often found associations between ACEs and TL compared to studies with clinical and older samples. Reviewing the included studies based on the "Stressor Exposure Characteristics" recently proposed by Epel et al. (2018) revealed a lack of detailed information regarding ACEs characteristics in many studies. Conclusion: Overall, it is difficult to achieve firm conclusions about associations of ACEs with TL due to the heterogeneity of study and ACE characteristics and the heterogeneity in reported findings. The field would benefit from more detailed descriptions of study samples and measurement of ACEs.

Consequences of measurement error in qPCR telomere data: A simulation study

The qPCR method provides an inexpensive, rapid method for estimating relative telomere length across a set of biological samples. Like all laboratory methods, it involves some degree of measurement error. The estimation of relative telomere length is done subjecting the actual measurements made (the Cq values for telomere and a control gene) to non-linear transformations and combining them into a ratio (the TS ratio). Here, we use computer simulations, supported by mathematical analysis, to explore how errors in measurement affect qPCR estimates of relative telomere length, both in cross-sectional and longitudinal data. We show that errors introduced at the level of Cq values are magnified when the TS ratio is calculated. If the errors at the Cq level are normally distributed and independent of true telomere length, those in the TS ratio are positively skewed and proportional to true telomere length. The repeatability of the TS ratio declines sharply with increasing error in measurement of the Cq values for telomere and/or control gene. In simulated longitudinal data, measurement error alone can produce a pattern of low correlation between successive measures of relative telomere length, coupled with a strong negative dependency of the rate of change on initial relative telomere length. Our results illustrate the importance of reducing measurement error: a small increase in error in Cq values can have large consequences for the power and interpretability of qPCR estimates of relative telomere length. The findings also illustrate the importance of characterising the measurement error in each dataset-coefficients of variation are generally unhelpful, and researchers should report standard deviations of Cq values and/or repeatabilities of TS ratios-and allowing for the known effects of measurement error when interpreting patterns of TS ratio change over time.

Familial support following childhood sexual abuse is associated with longer telomere length in adult females

Robust associations between adverse childhood experiences and shortened telomere length exist, but few studies have examined factors that may moderate this association, particularly with a resilience framework. The present study examined the association between exposure to childhood sexual abuse (and abuse severity) and mean telomere length, and whether social support and optimism moderated this association. The sample included 99 White monozygotic female twins, ranging in age from 35 to 70 (M_age = 52.74, SD = 8.55 years), who provided a blood sample for telomere assay, and data on their childhood sexual abuse history, trait optimism, and current social support. Linear mixed effects models were employed to test study hypotheses. There were no effects of exposure to abuse or abuse severity on mean telomere length, nor were there main or moderating effects of optimism, in analyses of the full sample. However, in analyses that only included women exposed to abuse, there was an abuse type × support interaction: among women who experienced abuse in forms other than intercourse, higher levels of social support were associated with longer mean telomere length. Findings from the current study clarify the role of childhood sexual abuse in telomere attrition, and identify one factor that may protect against the negative biological effects of childhood sexual abuse.

A scoping systematic review of social stressors and various measures of telomere length across the life course

Numerous studies examine the relationship between social stressors and telomere length (TL). Beyond considering methods and major findings, this scoping systematic review takes a novel approach as it groups studies according to the types of social stressor considered and by age groups. Following PRISMA guidelines, we searched PubMed, Web of Science, Embase, and Scopus. We included all English-language human subject research articles that modeled any measure of TL as a dependent variable and exposure to a social stressor as an independent variable. For the sample of 105 articles, we summarized methods and findings by type of social stressor (socioeconomic stressors, stressful life events, work-related stressors, and neighborhood stressors) and by age of the study population (infants/children, middle-aged adults, older adults, and mixed samples of middle-aged and older adults). We found more variation in TL measurement methodology in studies of infants/children and older adults than in studies focusing on middle-aged adults. The most consistent finding was a relationship between early-life stressors and shorter TL. Work and neighborhood stressors, and older populations, are currently understudied. Across all stressors, limited evidence suggests that the stress-TL relationship may be moderated by characteristics such as age, sex, and race/ethnicity. We conclude with specific suggestions for future research.

Telomere length and childhood trauma in Colombians with depressive symptoms

OBJECTIVE

Childhood trauma and telomere length (TL) are important risk factors for major depressive disorder. We examined whether there was an association between childhood trauma and TL in a sample of Colombians who were assessed for depressive symptoms.

METHODS

We applied the Center for Epidemiologic Studies Depression scale, the Patient Health Questionnaire-9, the Hospital Anxiety and Depression scale and the Childhood Trauma Questionnaire to 92 Colombian subjects (mean age = 21). TL was measured with quantitative PCR. Spearman's correlation coefficient (rs) was used to analyze the relationship between childhood trauma scores and TL.

RESULTS

We found a significant correlation between TL and sexual abuse scores (rs = 0.428, p = 0.002) in individuals with higher depressive symptom scores.

CONCLUSION

This is the first report of a significant association between TL and sexual abuse in a Latin American sample and provides additional evidence about the role of childhood trauma and TL in neuropsychiatric disorders.

Early life adversity and telomere length: a meta-analysis

Early adversity, in the form of abuse, neglect, socioeconomic status and other adverse experiences, is associated with poor physical and mental health outcomes. To understand the biologic mechanisms underlying these associations, studies have evaluated the relationship between early adversity and telomere length, a marker of cellular senescence. Such results have varied in regard to the size and significance of this relationship. Using meta-analytic techniques, we aimed to clarify the relationship between early adversity and telomere length while exploring factors affecting the association, including adversity type, timing and study design. A comprehensive search in July 2016 of PubMed/MEDLINE, PsycINFO and Web of Science identified 2462 studies. Multiple reviewers appraised studies for inclusion or exclusion using a priori criteria; 3.9% met inclusion criteria. Data were extracted into a structured form; the Newcastle-Ottawa Scale assessed study quality, validity and bias. Forty-one studies (N=30 773) met inclusion criteria. Early adversity and telomere length were significantly associated (Cohen's d effect size=-0.35; 95% CI, -0.46 to -0.24; P<0.0001). Sensitivity analyses revealed no outlier effects. Adversity type and timing significantly impacted the association with telomere length (P<0.0001 and P=0.0025, respectively). Subgroup and meta-regression analyses revealed that medication use, medical or psychiatric conditions, case-control vs longitudinal study design, methodological factors, age and smoking significantly affected the relationship. Comprehensive evaluations of adversity demonstrated more extensive telomere length changes. These results suggest that early adversity may have long-lasting physiological consequences contributing to disease risk and biological aging.

The fetal programming of telomere biology hypothesis: an update

Research on mechanisms underlying fetal programming of health and disease risk has focused primarily on processes that are specific to cell types, organs or phenotypes of interest. However, the observation that developmental conditions concomitantly influence a diverse set of phenotypes, the majority of which are implicated in age-related disorders, raises the possibility that such developmental conditions may additionally exert effects via a common underlying mechanism that involves cellular/molecular ageing-related processes. In this context, we submit that telomere biology represents a process of particular interest in humans because, firstly, this system represents among the most salient antecedent cellular phenotypes for common age-related disorders; secondly, its initial (newborn) setting appears to be particularly important for its long-term effects; and thirdly, its initial setting appears to be plastic and under developmental regulation. We propose that the effects of suboptimal intrauterine conditions on the initial setting of telomere length and telomerase expression/activity capacity may be mediated by the programming actions of stress-related maternal-placental-fetal oxidative, immune, endocrine and metabolic pathways in a manner that may ultimately accelerate cellular dysfunction, ageing and disease susceptibility over the lifespan. This perspectives paper provides an overview of each of the elements underlying this hypothesis, with an emphasis on recent developments, findings and future directions.This article is part of the theme issue 'Understanding diversity in telomere dynamics'.

Association between childhood trauma and accelerated telomere erosion in adulthood: A meta-analytic study

BACKGROUND

Childhood trauma has long-term sequelae on health status and contributes to numbers of somatic and mental disorders in later life. Findings from experimental studies in animals suggest that telomere erosion may be a mediator of this relationship. However, results from human studies are heterogeneous. To address these inconsistencies, we performed a meta-analysis regarding the association between childhood trauma and telomere length in adulthood.

METHOD

Articles were identified by systematically searching the Medline, EMBASE and Web of Science databases. Twenty four studies, which include twenty six sample sets and 30,919 participants, met the inclusion criteria for meta-analyses.

RESULTS

This meta-analyses revealed that individuals experienced childhood trauma have accelerated telomere erosion in adulthood, with a small effect size (r = -0.05, 95% CI = -0.08-0.03, p < 0.001). Subgroup analyses by type of childhood trauma revealed a trend in difference between groups (Q = 5.24, p = 0.07). Analyses for individual trauma types revealed a significant association between childhood separation and telomere erosion (r = -0.09, p < 0.001), but not for physical abuse, sexual abuse and loss of a parent.

CONCLUSION

This meta-analysis demonstrated a significant association between childhood trauma and accelerated telomere erosion in adulthood, and further revealed that different trauma types have various impacts on telomere. Additional research on the mechanism that links the individual types of childhood trauma with telomere is needed in the future.

Prospective associations of psychosocial adversity in childhood with risk factors for cardiovascular disease in adulthood: the MRC National Survey of Health and Development

BACKGROUND

Studies assessing associations of childhood psychosocial adversity (e.g. sexual abuse, physical neglect, parental death), as opposed to socioeconomic adversity, with cardiovascular disease (CVD) risk factors in adulthood are scarce. We aimed to assess associations of various forms of psychosocial adversity and cumulative adversity in childhood, with multiple CVD risk factors in mid-life.

METHODS

Participants were from the MRC National Survey of Health and Development. Childhood psychosocial risk factors were reported prospectively by parents from 1950-1957, and retrospectively by participants at mean age 43 years in 1989. CVD risk factors were assessed at mean age 60-64 years in 2006-2011. Associations of a summary score of total psychosocial adversity and CVD risk in adulthood were assessed.

RESULTS

There was no consistent evidence that cumulative psychosocial adversity, nor any specific form of psychosocial adversity in childhood, was associated with CVD risk factors in late adulthood. There was some evidence that parental death in the first 15 years was associated with higher SBP (Beta: 0.23, 95% confidence interval: 0.06 to 0.40, P=0.01) and DBP (Beta: 0.15, 95% confidence interval: -0.01 to 0.32, P=0.07).

CONCLUSIONS

We found no evidence that exposure to greater psychosocial adversity, or specific forms of psychosocial adversity during childhood is associated with adult CVD risk factors. Further large population studies are needed to clarify whether parental death is associated with higher systolic and diastolic blood pressure.

History of child maltreatment and telomere length in immune cell subsets: Associations with stress- and attachment-related hormones

Experiencing maltreatment during childhood can have long-lasting consequences for both mental and physical health. Immune cell telomere length (TL) shortening might be one link between child maltreatment (CM) experiences and adverse health outcomes later in life. While the stress hormone cortisol has been associated with TL attrition, the attachment-related hormone oxytocin may promote resilience. In 15 mothers with and 15 age- and body mass index-matched mothers without CM, we assessed TL in peripheral blood mononuclear cells and selected immune cell subsets (monocytes, naive, and memory cytotoxic T cells) by quantitative fluorescence in situ hybridization, as well as peripheral cortisol and oxytocin levels. Memory cytotoxic T cells showed significantly shorter TL in association with CM, whereas TL in monocytes and naive cytotoxic T cells did not significantly differ between the two groups. Across both groups, cortisol was negatively associated with TL, while oxytocin was positively associated with TL in memory cytotoxic T cells. These results indicate that long-lived memory cytotoxic T cells are most affected by the increased biological stress state associated with CM. Keeping in mind the correlational and preliminary nature of the results, the data suggest that cortisol may have a damaging and oxytocin a protective function on TL.

The effects of early life adversity on the immune system

Early life adversity (ELA) is associated with a higher risk for diseases in adulthood. Although the pathophysiological effects of ELA are varied, there may be a unifying role for the immune system in all of the long-term pathologies such as chronic inflammatory disorders (autoimmune diseases, allergy, and asthma). Recently, significant efforts have been made to elucidate the long-term effects ELA has on immune function, as well as the mechanisms underlying these immune changes. In this review, we focus on data from human studies investigating immune parameters in relation to post-natal adverse experiences. We describe the current understanding of the 'ELA immune phenotype', characterized by inflammation, impairment of the cellular immune system, and immunosenescence. However, at present, data addressing specific immune functions are limited and there is a need for high-quality, well powered, longitudinal studies to unravel cause from effect. Besides the immune system, also the stress system and health behaviors are altered in ELA. We discuss probable underlying mechanisms based on epigenetic programming that could explain the ELA immune phenotype and whether this is a direct effect of immune programming or an indirect consequence of changes in behavior or stress reactivity. Understanding the underlying mechanisms will help define effective strategies to prevent or counteract negative ELA-associated outcomes.

Food addiction as a proxy for eating disorder and obesity severity, trauma history, PTSD symptoms, and comorbidity

PURPOSE

Food addiction (FA) is a newly defined yet still controversial condition that has important etiological, developmental, treatment, prevention, and social policy implications. In this review, the case is made that FA (or high scores on the Yale Food Addiction Scale) may be used as a proxy measure for a matrix of interrelated clinical features, including greater eating disorder severity, greater obesity severity, more severe trauma histories, greater symptoms of posttraumatic stress disorder (PTSD), greater psychiatric comorbidity, as well as greater medical morbidity and mortality.

METHODS

A Medline search was undertaken using the following terms: food addiction cross-referenced with eating disorders (anorexia nervosa, bulimia nervosa, binge eating disorder, and binge eating), obesity, trauma, posttraumatic stress disorder, and comorbidity.

RESULTS

The thesis is that the identification and acknowledgment of the concept of FA, when integrated into an overall, trauma-focused and transdiagnostic treatment approach, are supported and can be useful in understanding clinically the "big picture."

CONCLUSIONS

Food addiction (FA) may be used as a proxy for (1) bulimic eating disorder severity, (2) complex trauma histories, (3) severity of PTSD and PTSD symptoms, (4) intensity of psychiatric comorbidity, (5) severity of obesity, as well as (6) their combination. Implications for developing treatment strategies are discussed. The case for a comprehensive management that requires careful attention to medical and psychiatric assessment and integrated care that incorporates trauma-focused treatment is made.

Epigenetic and Neural Circuitry Landscape of Psychotherapeutic Interventions

The science behind psychotherapy has garnered considerable interest, as objective measures are being developed to map the patient's subjective change over the course of treatment. Prenatal and early life influences have a lasting impact on how genes are expressed and the manner in which neural circuits are consolidated. Transgenerationally transmitted epigenetic markers as well as templates of enhanced thought flexibility versus evasion can be passed down from parent to child. This influences gene expression/repression (impacting neuroplasticity) and kindling of neurocircuitry which can perpetuate maladaptive cognitive processing seen in a number of psychiatric conditions. Importantly, genetic factors and the compounding effects of early life adversity do not inexorably lead to certain fated outcomes. The concepts of vulnerability and resilience are becoming more integrated into the framework of "differential susceptibility," speaking to how corrective environmental factors may promote epigenetic change and reconfigure neural templates, allowing for symptomatic improvement. Psychotherapy is one such factor, and this review will focus on our current knowledge of its epigenetic and neurocircuitry impact.

The Relationship Between Childhood Psychosocial Stressor Level and Telomere Length: A Meta-Analysis

This meta-analysis examined the association between the level of childhood psychosocial stressors and telomere length, an important health biomarker. The meta-analysis, including 27 samples and 16,238 participants, found a significant association of -0.08 between a higher level of childhood stressors and shorter telomere length at a mean age of 42 across studies. Moderator analyses showed a trend in the direction of effect sizes being significantly larger with shorter times between the stressors and telomere measurement. Moderator analyses showed significantly higher effect sizes for studies that used a categorical method for assessing child stressor level and for assays completed with qPCR rather than with the Southern blot method. There was no significant moderation of effect size by whether study assayed leukocytes or buccal cells, whether the study assessed child stressor level by memory-based recall versus archival records, and whether the study controlled for age, sex, or additional variables. The results, focused on childhood events, add to prior findings that perceived stress and negative emotions are associated with telomere length.

Posttraumatic stress disorder and accelerated aging: PTSD and leukocyte telomere length in a sample of civilian women

BACKGROUND

Studies in male combat veterans have suggested posttraumatic stress disorder (PTSD) is associated with shorter telomere length (TL). We examined the cross-sectional association of PTSD with TL in women exposed to traumas common in civilian life.

METHODS

Data are from a substudy of the Nurses' Health Study II (N = 116). PTSD and subclinical PTSD were assessed in trauma-exposed women using diagnostic interviews. An array of health behaviors and conditions were assessed. DNA was extracted from peripheral blood leukocytes (collected 1996-1999). Telomere repeat copy number to single gene copy number (T/S) was determined by quantitative real-time PCR telomere assay. We used linear regression models to assess associations and examine whether a range of important health behaviors (e.g., cigarette smoking) and medical conditions (e.g., hypertension) previously associated with TL might explain a PTSD-TL association. We further examined whether type of trauma exposure (e.g., interpersonal violence) was associated with TL and whether trauma type might explain a PTSD-TL association.

RESULTS

Relative to not having PTSD, women with a PTSD diagnosis had shorter log-transformed TL (β = -.112, 95% confidence interval (CI) = -0.196, -0.028). Adjustment for health behaviors and medical conditions did not attenuate this association. Trauma type was not associated with TL and did not account for the association of PTSD with TL.

CONCLUSIONS

Our results add to growing evidence that PTSD may be associated with more rapid cellular aging as measured by telomere erosion. Moreover, the association could not be explained by health behaviors and medical conditions assessed in this study, nor by type of trauma exposure.

Stressful life events and leucocyte telomere length: Do lifestyle factors, somatic and mental health, or low grade inflammation mediate this relationship? Results from a cohort of Danish men born in 1953

Exposure to psychosocial stress is associated with increased risk of a number of somatic and mental disorders with relation to immune system functioning. We aimed to explore whether stressful events in early and recent life was associated with leucocyte telomere length (TL), which is assumed to reflect the accumulated burden of inflammation and oxidative stress occurring during the life course. We specifically aimed to address whether childhood constitutes a sensitive period and how much of the relation between stressful life events and TL is mediated through somatic and mental health, lifestyle, and markers of low-grade inflammation. A cohort of Danish men born in 1953 has been followed since birth in the Metropolit Cohort. These men underwent a health examination including blood sampling in 2010 and a subset of 324 also had a quantitative PCR-based measurement of TL. The relation between stressful life events and TL was analysed using structural equation modelling, which also provided an estimate of the proportion of the total effect mediated by somatic and mental health (cardiovascular disease, body mass and depressive mood), lifestyle factors, and low grade inflammation (C-reactive protein (CRP), interleukin (IL)-6 and IL-10). Total number of stressful events experienced during the life course was not associated with TL. In terms of sensitive periods, we found that number of stressful events in childhood was associated with shorter TL (β_{per number stressful events in childhood}=-0.02(SE=-0.02); P=0.05). This relation was particularly strong for being placed away from home (β=-0.16; P<0.000). Thirty percent of the total effect of stressful events in childhood on TL was mediated by the included variables, with the largest proportion being mediated through depressive mood (16%) and CRP (9%). This study suggests that stressful events in childhood are associated with shorter TL in middle-aged men and that part of this relation is explained by depressive mood and low grade inflammation.

Childhood Personality, Betrayal Trauma, and Leukocyte Telomere Length in Adulthood: A Lifespan Perspective on Conscientiousness and Betrayal Traumas as Predictors of a Biomarker of Cellular Aging

Conscientiousness is associated with longevity. As such, identifying the biological pathways linking personality to mortality is important. This study employs longitudinal data spanning >40 years to test prospective associations with Leukocyte Telomere Length (LTL), a potential marker of cellular aging. Because telomeres shorten over time, and are sensitive to oxidative stress, shorter LTL may reflect cumulative damage associated with negative health behaviors and past stressful events. We investigated childhood conscientiousness as a protective factor, expecting an association with longer LTL in adulthood, possibly reflecting slower LTL shortening. Potential lifespan pathways involving childhood trauma, smoking behaviors, and Body Mass Index (BMI) were explored. Childhood conscientiousness showed a small raw association with LTL (r = .08, p = .04), although this effect did not persist when controlling for age and sex. Despite this lack of a direct effect on LTL, we detected an indirect effect operating jointly through BMI and smoking. Higher rates of childhood betrayal trauma were associated with shorter LTL. Contrary to our hypothesis that conscientiousness would buffer this effect, we found evidence for an interaction with childhood betrayal traumas where the association between childhood betrayal traumas and LTL was larger for those higher on conscientiousness in childhood.