Cardiopulmonary response to exercise in adults born very preterm.

This study aims to compare cardiopulmonary response to aerobic exercise between young adults born very preterm, including a subgroup with bronchopulmonary dysplasia (BPD), and term controls.Seventy-one adults (18-29 years) born <30 weeks' gestational age (24 with BPD) and 73 term controls were recruited. Assessment included cardiopulmonary exercise testing with impedance cardiography. We compared group differences in peak O 2 consumption (peak VO 2 ) and in ventilatory and cardiovascular responses to exercise using linear regression analyses.Preterm participants had reduced peak VO 2 (mean difference -2.7; 95% CI -5.3, -0.1 mL·kg -1 lean body mass·min -1 ) versus controls. Those with BPD achieved lower peak work-rate compared to term controls (-21; 95% CI -38, -5 watts). There was no difference across groups in breathing reserve, ventilatory efficiency, peak heart rate and cardiac output. VO 2 to work-rate relationship (ΔVO 2 /ΔWR) was reduced in preterm versus term. Peak systolic blood pressure and circulatory power (systolic blood pressure*VO 2 ) were also lower in BPD versus term controls. In the preterm group, longer NICU stay and lower peak cardiac output were associated with lower peak VO 2 Results suggest limitations with peripheral O 2 uptake in the muscle with reduced ΔVO 2 /ΔWR and peak circulatory power, but normal cardiac output. Investigations into skeletal muscle perfusion and O 2 use during exercise are warranted to better understand mechanisms of exercise limitation.