Table 3.

Multiple Regression with the Aortic Augmentation Index as the Dependent Variable (All Participants, N = 174)

	Aortic AIx, Model 1		Aortic AIx, Model 2
	B (95% CI)	P Value	B (95% CI)	P Value
Post-bronchodilator FEV1
FEV1	0.40 (−2.54 to 3.33)	0.790	0.69 (−1.90 to 3.29)	0.599
EP without BPD (ref., control group)	5.66 (1.68 to 9.64)	0.006	5.69 (2.16 to 9.21)	0.002
EP with BPD (ref., control group)	6.31 (2.64 to 9.98)	0.001	7.4 (4.08 to 10.72)	<0.001
Heart rate, bpm	—	—	−0.41 (−0.53 to −0.29)	<0.001
MAP, mm Hg	—	—	0.29 (0.11 to 0.48)	0.002
Post-bronchodilator FVC
FVC	−0.10 (−2.67 to 2.47)	0.939	−0.12 (−2.41 to 2.18)	0.921
EP without BPD (ref., control group)	5.51 (1.57 to 9.45)	0.006	5.43 (1.93 to 8.93)	0.003
EP with BPD (ref., control group)	6.02 (2.67 to 9.37)	0.001	6.92 (3.85 to 9.98)	<0.001
Heart rate, bpm	—	—	−0.41 (−0.53 to −0.29)	<0.001
MAP, mm Hg	—	—	0.29 (0.11 to 0.48)	0.002
Bronchodilator reversibility (>12% change in FEV1)
Reversible FEV1	−5.58 (−8.96 to −2.20)	0.001	−4.56 (−7.58 to −1.54)	0.003
EP without BPD (ref., control group)	5.48 (1.73 to 9.23)	0.004	5.42 (2.08 to 8.76)	0.002
EP with BPD (ref., control group)	7.29 (4.12 to 10.47)	<0.001	7.93 (5.04 to 10.83)	<0.001
Heart rate, bpm	—	—	−0.39 (−0.51 to −0.27)	<0.001
MAP, mm Hg	—	—	0.28 (0.10 to 0.46)	0.002

Definition of abbreviations: AIx = augmentation index; B = effect size; BPD = neonatal bronchopulmonary dysplasia; bpm = beats per minute; CI = confidence interval; EP = extremely preterm; MAP = mean arterial pressure; ref. = reference to control group.

Variables entered in model 1: group variable (EP with BPD, EP without BPD, and control subjects), age at testing (years), height (cm), weight (kg), sex, ethnicity, regular exposure to smoking, and maternal smoking during pregnancy. Model 2 was further adjusted for MAP (mm Hg) and heart rate (bpm).