Telomere length in preterm-born children with bronchopulmonary dysplasia (BPD)

Abstract

<b>Background:</b> Telomere shortening occurs after each cell division. Since preterm-born babies often develop acute lung injury and BPD, they may have shortened telomeres due to greater cell division especially early in life. <b>Aims:</b> Is telomere length decreased in babies who develop BPD or have low lung function defined as percent predicted FEV₁ of ≤85%? <b>Methods:</b> Saliva samples were obtained from preterm- (≤34 weeks’ gestation) and term-born (≥37 weeks’ gestation) children. Telomere length was measured in the extracted DNA by using the ScienCell qPCR method (Ca, USA). BPD was defined as oxygen-dependency at 28 days of age and further classified into those with mild or moderate/severe BPD. Groups were compared using ANOVA and posthoc Bonferroni correction or independent t-tests. <b>Results:</b> 534 children had satisfactory telomere data including 68 preterm-born with BPD (mean birthweight 1092 (SD 388) g; gestation: 27.3 (2.1) weeks), 310 preterm-born without BPD (BW 1867 (491) g; gestation 31.9 (1.8) weeks) and 149 term controls (BW 3465 (513) g; gestation 39.8 (1.3) weeks). Mean telomere length per diploid cell was 409.16 (101.98) for the BPD group; 425.55 (126.40) for preterm controls and 423.02 (105.54) for term controls, which were not significantly different between the three groups. Telomere length was not related to severity of lung disease. However, telomere length was longer in those infants who had intrauterine growth restriction (IUGR) at birth: 464.64 (166.25) vs 418.56 (110.68) in the no-IUGR group; and in females: 440.20 (130.06) vs 405.68 (101.51). <b>Conclusions:</b> Although telomere length was not affected by BPD or prematurity-associated lung disease, it was longer in females and in the IUGR group.