Angiopoietin 2 concentrations in infants developing bronchopulmonary dysplasia: Attenuation by dexamethasone

Objectives: To study the association between angiopoietin 2 (Ang2) concentrations in tracheal aspirates (TAs) and adverse outcome (bronchopulmonary dysplasia (BPD)/death) in ventilated premature infants (VPIs) and modulation of Ang2 concentrations with dexamethasone (Dex) use. Study Design: Serial TA samples were collected on days 1, 3, 5 and7, and Ang2 concentrations were measured. Ang2 TA concentrations were compared prior to and after 48 to 72h of using Dex. Result: A total of 151 TA samples were collected from 60 VPIs. BPD was defined as the oxygen requirement at 36 weeks postmenstrual age (PMA). Twelve infants (mean ± s.d.) (gestational age (GA) 26.5 ± 2.1 weeks, birth weight (BW) 913 ± 230 g) had no BPD, 32 infants (GA 25.8 ± 1.4 weeks, BW 768 ± 157 g) developed BPD and 16 infants (GA 24.5 ± 1.1 weeks, BW 710 ± 143 g) died before 36 weeks PMA. Ang2 concentrations were significantly lower in infants with no BPD (median, 25th and 75th percentile) (157, 16 and 218pg mg^-1) compared with those who developed BPD (234, 138 and 338pg mg^-1, P=0.03) or BPD and/or death (234, 157 and 347 pg mg^-1, P=0.017), in the first week of life. Twenty-six VPIs (BW 719 ± 136 g, GA 25.1 ± 1.3 weeks) received 27 courses of Dex. Ang2 concentrations before starting Dex were 202, 137 and 278 pg mg^-1 and significantly decreased to 144, 0 and 224 pg mg^-1 after therapy (P=0.007). Conclusions: Higher Ang2 concentrations in TAs are associated with the development of BPD or death in VPIs. Dex use suppressed Ang2 concentrations.