Posttraumatic Stress Disorder and Not Depression Is Associated with Shorter Leukocyte Telomere Length: Findings from 3,000 Participants in the Population-Based KORA F4 Study

Thomas Illig,Anne Catharina Brockhaus,Christian Gieger,Sibylle Häfner,Johannes Kruse,Annette Peters,Karoline Lukaschek,H Erich Wichmann,Eva Albrecht,Rebecca T Emeny,Veryan Codd,Nilesh J Samani,Karl-Heinz Ladwig,Jens Baumert

doi:10.1371/journal.pone.0064762

Abstract

BackgroundA link between severe mental stress and shorter telomere length (TL) has been suggested. We analysed the impact of Posttraumatic Stress Disorder (PTSD) on TL in the general population and postulated a dose-dependent TL association in subjects suffering from partial PTSD compared to full PTSD.MethodsData are derived from the population-based KORA F4 study (2006–2008), located in southern Germany including 3,000 individuals (1,449 men and 1,551 women) with valid and complete TL data. Leukocyte TL was measured using a quantitative PCR-based technique. PTSD was assessed in a structured interview and by applying the Posttraumatic Diagnostic Scale (PDS) and the Impact of Event Scale (IES). A total of 262 (8.7%) subjects qualified for having partial PTSD and 51 (1.7%) for full PTSD. To assess the association of PTSD with the average TL, linear regression analyses with adjustments for potential confounding factors were performed.ResultsThe multiple model revealed a significant association between partial PTSD and TL (beta = −0.051, p = 0.009) as well as between full PTSD and shorter TL (beta = −0.103, p = 0.014) indicating shorter TL on average for partial and full PTSD. An additional adjustment for depression and depressed mood/exhaustion gave comparable beta estimations.ConclusionsParticipants with partial and full PTSD had significantly shorter leukocyte TL than participants without PTSD. The dose-dependent variation in TL of subjects with partial and full PTSD exceeded the chronological age effect, and was equivalent to an estimated 5 years in partial and 10 years in full PTSD of premature aging.

Highlights

Telomeres are tandem repeats of hexamers (TTAGGG) at the ends of chromosomes that protect against spontaneous DNA damage and preserve genomic integrity
Description of the study population by Posttraumatic Stress Disorder (PTSD) symptoms In the total study sample, 2,687 (89.6%) subjects were free of PTSD while 262 (8.7%) subjects suffered from partial PTSD and 51 (1.7%) from full PTSD
Concerning classical risk factors (BMI, smoking status, alcohol consumption, physical inactivity, Total cholesterol (TC)/ high density lipoprotein cholesterol (HDL-C), chronic diseases), no significant univariate differences between PTSD groups were observed except for actual hypertension, which was more frequent among non-PTSD participants and for history of chronic diseases, which was more frequent among partial and full PTSD participants

Summary

Introduction

Telomeres are tandem repeats of hexamers (TTAGGG) at the ends of chromosomes that protect against spontaneous DNA damage and preserve genomic integrity. Sustained states of severe mental stress and adverse affective conditions have been associated with shorter TL. Among the first investigations were two studies which observed shorter TL in premenopausal women with a long duration of high perceived stress due to caring for chronically ill children [15] or Alzheimer’s disease patients [16]. The effect of childhood adversities on TL was stronger than suffering from anxiety disorder in adult life [23]. In a 5-year follow-up study, Shalev et al [24] reported shorter telomeres in children who experienced violence. We analysed the impact of Posttraumatic Stress Disorder (PTSD) on TL in the general population and postulated a dose-dependent TL association in subjects suffering from partial PTSD compared to full PTSD

Methods

Results

Discussion

Conclusion