Associations between telomere length and symptoms of posttraumatic stress disorder and appetitive aggression in trauma-exposed men

Association between telomere length and psychiatric disorders: a bidirectional Mendelian randomization study

Observational studies have suggested that shorter telomere length (TL) may be a risk factor for psychiatric disorders. However, whether this association underlie causal effects remains unknown. This study aims to investigate the potential association between TL and psychiatric disorders by conducting a bidirectional Mendelian randomization (MR) study. Summary statistics for TL were obtained from the UK Biobank (n = 472,174), while summary statistics for ten psychiatric disorders were acquired from the Psychiatric Genomics Consortium (PGC). The inverse-variance weighted (IVW) method was used as primary analysis, with the MR-Egger, weighted median, MR-PRESSO, simple mode, and weighted mode approaches were utilized as sensitivity analyses. Our findings indicated a potential association between genetic predisposition to attention deficit hyperactivity disorder (ADHD) and shortened TL (Beta = - 0.039, SE = 0.011, P = 4.00E-04). Additionally, posttraumatic stress disorder (PTSD) may be was potentially associated with TL (Beta = - 0.014, SE = 0.006, P = 0.019). Our findings suggest a potential correlation between ADHD and TL, yet no significant association exists between TL and other psychiatric disorders. Nevertheless, considering the small effect size and the fact that it might have limited practical clinical significance, TL may not function as a biomarker for psychiatric disorders.

Telomere Dynamics in Post-Traumatic Stress Disorder: A Critical Synthesis

Post-traumatic stress disorder (PTSD), a mental disorder caused by exposure to traumatic stress, affects 5-10% of the world's population. There is some evidence that PTSD is associated with accelerated cellular aging, leading to an increased risk of medical and neurodegenerative comorbidities. Alterations in telomere length (TL) and telomerase enzyme activity have been proposed as biomarkers of this process. This hypothesis was seemingly confirmed in preliminary research, but more recent studies have yielded mixed results. The current narrative review was conducted to provide a critical synthesis of existing research on telomere length and telomerase in PTSD. Data from 26 clinical studies suggest that TL in PTSD is highly variable and may be influenced by methodological, demographic, trauma-related, and psychosocial factors. There is no evidence for altered telomerase activity in PTSD. In contrast, animal research suggests that exposure to traumatic stress does lead to TL shortening. Overall, it is likely that TL is not, by itself, a reliable biomarker of cellular aging in PTSD. Other markers of cellular senescence, such as epigenetic changes, may prove to be more specific in measuring this process in patients with PTSD.

Association between telomere length and anorexia of ageing: a cross-sectional study conducted with community-dwelling older people

BACKGROUND

To verify whether shorter telomere length is associated with anorexia of ageing in community-dwelling older people.

METHODS

Conducted as a cross-sectional investigation, the study enrolled 448 participants residing in an urban area of a municipality in Brazil. Relative telomere length in blood samples was measured using quantitative polymerase chain reaction (qPCR), whereas the presence of anorexia of ageing was determined using the Simplified Appetite Nutritional Questionnaire. Data analysis employed multiple logistic regression.

RESULTS

Among the 448 older individuals surveyed, 70.69% were female, and the predominant age bracket ranged from 60 to 69 years (45.08%). Approximately 25% exhibited the shortest telomeric length, with a corresponding anorexia of ageing prevalence of 41.16%. Older individuals with diminished telomere lengths displayed an increased likelihood of experiencing anorexia of ageing (odds ratio [OR] = 1.92; 95% confidence interval [CI] = 1.12-3.29), independent of factors such as gender, age group, depressive symptoms, pain and performance in basic daily life activities.

CONCLUSIONS

The observed association between anorexia of ageing and a telomeric biomarker underscores the imperative to meticulously evaluate the nutritional dimensions of older people, with a view to implementing interventions that may enhance their overall health status.

Psychological and biological mechanisms linking trauma with cardiovascular disease risk

Cardiovascular disease (CVD) is the leading cause of death and disability worldwide, and experiences of psychological trauma have been associated with subsequent CVD onset. Identifying key pathways connecting trauma with CVD has the potential to inform more targeted screening and intervention efforts to offset elevated cardiovascular risk. In this narrative review, we summarize the evidence for key psychological and biological mechanisms linking experiences of trauma with CVD risk. Additionally, we describe various methodologies for measuring these mechanisms in an effort to inform future research related to potential pathways. With regard to mechanisms involving posttraumatic psychopathology, the vast majority of research on psychological distress after trauma and CVD has focused on posttraumatic stress disorder (PTSD), even though posttraumatic psychopathology can manifest in other ways as well. Substantial evidence suggests that PTSD predicts the onset of a range of cardiovascular outcomes in trauma-exposed men and women, yet more research is needed to better understand posttraumatic psychopathology more comprehensively and how it may relate to CVD. Further, dysregulation of numerous biological systems may occur after trauma and in the presence of posttraumatic psychopathology; these processes of immune system dysregulation and elevated inflammation, oxidative stress, mitochondrial dysfunction, renin-angiotensin system dysregulation, and accelerated biological aging may all contribute to subsequent cardiovascular risk, although more research on these pathways in the context of traumatic stress is needed. Given that many of these mechanisms are closely intertwined, future research using a systems biology approach may prove fruitful for elucidating how processes unfold to contribute to CVD after trauma.

Adverse and traumatic exposures, posttraumatic stress disorder, telomere length, and hair cortisol – Exploring associations in a high-risk sample of young adult residential care leavers

Background

Childhood adversities (CAs), potentially traumatic exposures (PTEs), and posttraumatic stress disorder (PTSD) are known to increase the risk for poor health outcomes, including diseases of aging and early mortality. Telomere length (TL) and hair cortisol concentrations (HCC) are biomarkers known to be associated with CA and PTEs, and PTSD, but there is considerable heterogeneity in findings.

Objectives

This study aims to investigate the association of CAs, PTEs, and PTSD with TL and HCC in a high-risk sample of young adults who were previously placed in youth residential care institutions throughout Switzerland.

Method

Our sample includes 130 participants (30.8% women, M _Age = 26.5 ± 3.7 years) with previous youth residential care placements (M_Placements= 3.9). CAs and PTEs, as well as PTSD, were assessed with self-reported questionnaires and semi-structured clinical interviews. Immune cell TL was measured with quantitative polymerase chain reaction (qPCR) in whole blood. Hair samples were collected for HCC measurement and assayed with high-sensitivity ELISA. Multivariate regression models were fitted to describe the associations between CAs, PTEs, and PTSD with TL and HCC, adjusting for covariates.

Results

In our high-risk sample, a higher burden of CAs, PTEs, Criterion A trauma, and PTSD was associated with longer TL. PTEs, Criterion A trauma, and PTSD were associated with lower HCC, however no significant associations between CAs and HCC were found. The magnitude of these effects varied depending on the dimensional or categorical nature of the stress-phenotype and the specific measure used.

Conclusions

Our findings are in contrast with many, but not all, previous studies of associations between adversity and both TL and HCC. For instance, our findings are in line with other studies that find a state of hypocortisolism in PTSD. Better measurement of adversities and trauma, multisystem biomarker approaches, and more research in larger high-risk samples at the upper end of the adversity-continuum is warranted.

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In this high-risk sample,childhood adversities, potential traumatic exposures, criterion A trauma, or posttraumatic stress disorder (PTSD) was associated with longer telomere length (TL).

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Potentially traumatic exposures, criterion A trauma, and PTSD were associated with lower hair cortisol concentrations.

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The magnitude of these effects varied depending on the dimensional or categorical nature of the stress-phenotype and the specific measure used.

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Hypocortisolism might explain findings of longer TL in participants with cumulated adverse and traumatic exposures.

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Research in high-risk populations is strongly needed as results across the entire spectrum of adversity exposures may not generalize to the top end of the spectrum.