Original Article

Molecular Psychiatry (2013) 18, 576–581; doi:10.1038/mp.2012.32; published online 24 April 2012

Exposure to violence during childhood is associated with telomere erosion from 5 to 10 years of age: a longitudinal study

I Shalev1,2, T E Moffitt1,2,3,4, K Sugden1,2,3,4, B Williams1,2,3,4, R M Houts1,2, A Danese4,5, J Mill4, L Arseneault4 and A Caspi1,2,3,4

  1. 1Department of Psychology and Neuroscience, Duke University, Durham, NC, USA
  2. 2Institute for Genome Sciences and Policy, Duke University, Durham, NC, USA
  3. 3Department of Psychiatry and Behavioral Sciences, Duke University, Durham, NC, USA
  4. 4Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King’s College London, London, UK
  5. 5Department of Child and Adolescent Psychiatry, Institute of Psychiatry, King’s College London, London, UK

Correspondence: Dr I Shalev, Department of Psychology and Neuroscience, Duke University, Suite 201 Grey House, 2020 West Main Street, Box 104410, Durham, NC 27708, USA. E-mail: idan.shalev@duke.edu

Received 2 December 2011; Revised 2 February 2012; Accepted 5 March 2012
Advance online publication 24 April 2012

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Abstract

There is increasing interest in discovering mechanisms that mediate the effects of childhood stress on late-life disease morbidity and mortality. Previous studies have suggested one potential mechanism linking stress to cellular aging, disease and mortality in humans: telomere erosion. We examined telomere erosion in relation to children's exposure to violence, a salient early-life stressor, which has known long-term consequences for well-being and is a major public-health and social-welfare problem. In the first prospective-longitudinal study with repeated telomere measurements in children while they experienced stress, we tested the hypothesis that childhood violence exposure would accelerate telomere erosion from age 5 to age 10 years. Violence was assessed as exposure to maternal domestic violence, frequent bullying victimization and physical maltreatment by an adult. Participants were 236 children (49% females; 42% with one or more violence exposures) recruited from the Environmental-Risk Longitudinal Twin Study, a nationally representative 1994–1995 birth cohort. Each child's mean relative telomere length was measured simultaneously in baseline and follow-up DNA samples, using the quantitative PCR method for T/S ratio (the ratio of telomere repeat copy numbers to single-copy gene numbers). Compared with their counterparts, the children who experienced two or more kinds of violence exposure showed significantly more telomere erosion between age-5 baseline and age-10 follow-up measurements, even after adjusting for sex, socioeconomic status and body mass index (B=−0.052, s.e.=0.021, P=0.015). This finding provides support for a mechanism linking cumulative childhood stress to telomere maintenance, observed already at a young age, with potential impact for life-long health.

Keywords:

childhood stress; cumulative violence exposure; erosion; longitudinal; telomere length