Effects of water, sanitation, handwashing, and nutritional interventions on telomere length among children in a cluster-randomized controlled trial in rural Bangladesh
Abstract
Background: Shorter childhood telomere length (TL) and more rapid TL attrition are widely regarded as manifestations of stress. However, the potential effects of health interventions on child TL are unknown. We hypothesized that a water, sanitation, handwashing (WSH), and nutritional intervention would slow TL attrition during the first two years of life. Methods: In a trial in rural Bangladesh (ClinicalTrials.gov, NCT01590095), we randomized geographical clusters of pregnant women into individual water treatment, sanitation, handwashing, nutrition, combined WSH, combined nutrition plus WSH (N+WSH), or control arms. We conducted a substudy enrolling children from the control arm and the N+WSH intervention arm. Participants and outcome assessors were not masked; analyses were masked. Relative TL was measured at 1 and 2 years after intervention, and the change in relative TL was reported. Analysis was intention-to-treat. Findings: Between May 2012 and July 2013, in the overall trial, we randomized 720 geographical clusters of 5551 pregnant women to a control or an intervention arm. In this substudy, after 1 year of intervention, we assessed a total of 662 children (341 intervention and 321 control) and 713 children after 2 years of intervention (383 intervention and 330 control). Children in the intervention arm had significantly shorter relative TL compared with controls after 1 year of intervention (difference -163 base pairs (bp), P=0.001). Between years 1 and 2, TL increased in the intervention arm (+76 bp) and decreased in the controls (-23 bp) (P=0.050). After 2 years, there was no difference between the arms (P=0.305). Interpretation: Our unexpected finding of increased telomere attrition during the first year of life in the intervention group suggests that rapid telomere attrition during this critical period could reflect the improved growth in the intervention group, rather than accumulated stress.
Data availability
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WASH Benefits Bangladesh Analysis of Telomere OutcomesDOI 10.17605/OSF.IO/EVC98.
Article and author information
Author details
Funding
Bill and Melinda Gates Foundation (Global Development grant OPPGD759)
- John M Colford
The funder approved the study design, but was not involved in data collection, analysis, interpretation or any decisions related to publication. The corresponding author had full access to all study data and final responsibility for the decision to submit for publication.
Reviewing Editor
- Eduardo Franco, McGill University, Canada
Ethics
Human subjects: Primary caregivers of all children provided written informed consent. The study protocols were approved by human subjects committees at icddr,b (PR-11063 and PR-14108), the University of California, Berkeley (2011-09-3652 and 2014-07-6561) and Stanford University (25863 and 35583).
Version history
- Received: June 7, 2017
- Accepted: October 3, 2017
- Accepted Manuscript published: October 5, 2017 (version 1)
- Version of Record published: November 7, 2017 (version 2)
- Version of Record updated: April 2, 2020 (version 3)
Copyright
© 2017, Lin et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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