Telomere length in the superager sample of the Vallecas Project cohort

Abstract

AbstractBackgroundSuperagers are individuals aged 80 and over with youthful episodic memory that can provide insights into protective mechanisms against age‐related memory loss and dementia. We aim to study telomere length in human superagers since telomere attrition is considered a hallmark of ageing and can explain some structural and functional changes occurring in an ageing organism. We therefore tested whether telomere length is associated with successful episodic memory of superagers.MethodTelomere length was measured in peripheral blood cells from 57 superagers (mean age 81.9 years ± 2.0 std, 61.4% women) and 48 age‐matched typical older adults with normal memory for age (mean age 82.4 years ± 1.9 std, 64.6% women) selected from the Vallecas Project cohort. A high‐throughput quantitative fluorescence in situ hybridization technique (HT Q‐FISH) (Life length, Spain) was used. This technology has a low detection limit of < 100 bp, enabling the quantification of short telomeres that can be more informative of telomere dysfunction than centrality measures.ResultSuperagers have significantly shorter median telomere lengths than typical older adults (p = 0.0009, t = ‐3.4) and show a higher proportion of short telomeres (<6 Kbp) (p = 0.0005, t = 3.6) and extremely short telomeres (<3 Kbp) (p = 9. 4×10−5; t = 4.1) than typical older adults. Thus, superagers have shorter average telomere lengths and a higher proportion of short telomeres, which are most associated with genome instability.ConclusionThe successful episodic memory of our superager population is not associated with long telomere length or the presence of fewer short telomeres measured in a cross‐sectional setting. Further analysis exploring telomere attrition rate of these two groups over time may help to interpret the current findings.