Background: A previous case-control study of 100 individuals found that short telomere length was associated with a 28-fold increased risk of chronic obstructive pulmonary disease (COPD).
Objectives: To test the hypothesis that short telomere length is associated with reduced lung function and an increased risk of COPD.
Methods: Observational study of 46 396 individuals from the Danish general population.
Measurements: Leucocyte telomere length and spirometry were measured. COPD was defined using either fixed forced expiratory volume in 1 s (FEV₁)/forced vital capacity (FVC) ratio <0.70 as suggested by the Global initiative for chronic Obstructive Lung Disease (GOLD) or FEV₁/FVC below the lower limit of normal (LLN).
Results: Telomere length decreased significantly with increasing age (p<10(-300)). FEV₁, FVC and FEV1/FVC decreased with decreasing telomere length quartiles (p trend: 5 × 10(-51), 5 × 10(-35) and 6 × 10(-137), respectively), but the associations attenuated after age and multivariable adjustment. The risk of COPD increased with decreasing telomere length quartile (p trend: p=7 × 10(-92) for GOLD; p=8 × 10(-44) for FEV₁/FVC below LLN), but associations also attenuated after adjustment. Unadjusted and multivariable adjusted OR for shortest versus longest telomere length quartiles were 2.06 (95% CI 1.91 to 2.22) and 1.15 (95% CI 1.06 to 1.25) for GOLD and 1.73 (95% CI 1.60 to 1.88) and 1.19 (95% CI 1.09 to 1.30) for FEV₁/FVC below LLN, respectively. Per 1000 base pairs decrease in telomere length, the multivariable adjusted OR was 1.07 (95% CI 1.03 to 1.10) for GOLD and 1.07 (95% CI 1.03 to 1.11) for FEV₁/FVC below LLN.
Conclusions: Short telomere length is associated with decreased lung function and with increased risk of COPD, but the associations are markedly attenuated after adjustment. Our data support a modest correlation between telomere length and the lung function indices examined.