Longitudinal changes in leukocyte telomere length and mortality in elderly Swedish men
Xiaotian Yuan1,*,,
Magnus Kronström2,*,,
Mai-Lis Hellenius3,,
Tommy Cederholm2,,
Dawei Xu1,,
Per Sjögren2,,
1 Department of Medicine, Division of Hematology, and Center for Molecular Medicine, Karolinska Institutet and Karolinska University Hospital Solna, SE-171 76 Stockholm, Sweden
2 Department of Public Health and Caring Sciences, Unit of Clinical Nutrition and Metabolism, Uppsala University, Uppsala, Sweden
3 Karolinska Institutet, Department of Medicine, Karolinska University Hospital, Solna, SE-171 76 Stockholm, Sweden
* Equal contribution
Received: June 12, 2018 Accepted: October 19, 2018 Published: October 29, 2018
Telomere length (TL) is considered an indicator of aging and age-related diseases, but longitudinal studies on TL changes and mortality are few. We therefore analyzed TL and longitudinal changes in TL in relation to all-cause, cardiovascular, and cancer mortality in 247 elderly Swedish men. TL was determined by the qPCR method at ages 71 and 81 and subsequent mortality cases were identified from the Swedish cause-of-death registry. Cox proportional hazard ratios were calculated during a mean follow-up of 7.4 years, during which 178 deaths occurred. Short telomeres at baseline was strongly associated with mortality risks, with a 40 to 70% increased risk of all-cause mortality, and a 2-fold increased risk of cancer mortality. Longitudinal changes in TL revealed shortening in 83% of individuals, whilst 10% extended their telomeres. TL attrition did not predict all-cause or cancer mortality, but we found a 60% decreased risk for cardiovascular mortality in those who shortened their telomeres. Our data show an increased risk of mortality in individuals with short baseline telomeres, but no relations to all-cause, and cancer mortality for changes in TL. Intriguingly, our data indicate lower risk of cardiovascular mortality with shortening of telomeres. The latter should be interpreted cautiously.
Abbreviations
BMI: body mass index;
CV: coefficient of variation;
CVD: Cardiovascular disease;
DNA: deoxyribonucleic acid;
HR: hazard ratio;
ICD: international statistical classification of diseases and related health problems;
qPCR: quantitative polymerase chain reaction;
TL: telomere length.