Journal article Open Access

Controlling for baseline telomere length biases estimates of the rate of telomere attrition.

Bateson, Melissa; Eisenberg, Dan T. A.; Nettle, Daniel

Published article, Supplementary Material, associated R script and dataset.

 

Abstract

Longitudinal studies have sought to establish whether environmental exposures such as smoking accelerate the attrition of individuals’ telomeres over time. These studies typically control for baseline telomere length (TL) by including it as a covariate in statistical models. However, baseline TL also differs between smokers and non-smokers, and telomere attrition is spuriously linked to baseline TL via measurement error and regression to the mean. Using simulated datasets, we show that controlling for baseline TL overestimates the true effect of smoking on telomere attrition. This bias increases with increasing telomere measurement error and increasing difference in baseline TL between smokers and non-smokers. Using a meta-analysis of longitudinal datasets, we show that as predicted, the estimated difference in telomere attrition between smokers and non-smokers is greater when statistical models control for baseline TL than when they do not, and the size of the discrepancy is positively correlated with measurement error. The bias we describe is not specific to smoking and also applies to other exposures. We conclude that to avoid invalid inference, models of telomere attrition should not control for baseline TL by including it as a covariate. Many claims of accelerated telomere attrition in individuals exposed to adversity need to be re-assessed.

Files (3.4 MB)
Name Size
Bateson Eisenberg & Nettle - R script revised Aug19.R
md5:f2d7080164afb4d42164de57bb29a2ef
59.0 kB Download
Bateson Eisenberg & Nettle Supplementary Material.pdf
md5:4b42c0645e780c3dccd8e0c974fc2c49
2.0 MB Download
Bateson, Eisenberg and Nettle 2019 published paper.pdf
md5:f261444debca7fee5826b26c4a200a9a
1.3 MB Download
Supplementary_dataset.CSV
md5:2059a7c4bad64ecbadfbe9cc2e5318b2
20.6 kB Download
626
486
views
downloads
All versions This version
Views 62696
Downloads 48671
Data volume 540.9 MB95.8 MB
Unique views 56686
Unique downloads 35747

Share

Cite as