Longitudinal changes in cardiopulmonary outcomes of adults born extremely prematurely: United Kingdom Oscillation Study.

Abstract

Background: During puberty, lung function of individuals born extremely prematurely can deteriorate putting them at risk of early chronic obstructive pulmonary disease (COPD). We hypothesise that young adults exposed to postnatal corticosteroids will have poorer lung and cardiac function, higher pulmonary artery pressures and poorer exercise tolerance compared to preterm born adults not exposed to postnatal steroids and term born adults. We further hypothesise lung function differences may be demonstrated depending on mode of ventilation at birth (high frequency oscillatory or conventional ventilation) in preterm born adults.

Methods: A prospective study of participants (aged 24-28) from the United Kingdom Oscillation Study (UKOS) and term born controls. Assessments will involve comprehensive lung function, cardiac ultrasound, exercise assessments, inflammatory cell and biomarker profiling and airway microbiome assessment. The primary outcome is the ratio of forced expiratory volume in 1 s/forced vital capacity (FEV₁/FVC); to detect a significant difference we will recruit 150 individuals. Statistical analysis will involve mixed effect models with adjustment for imbalances and sensitivity analysis.

Discussion: The results may identify adults born extremely preterm at increased risk of COPD and pulmonary hypertension (PH) who might benefit from interventions to delay the onset of COPD and cardiovascular complications such as PH.

Impact: Adults born extremely prematurely in the modern era of neonatal care are an emerging population whose long-term outcomes have infrequently been reported. This study will describe their cardiac and lung function, pulmonary artery pressures, exercise capacity and immunobiological profile. We aim to identify risk factors for worse outcomes such as early chronic obstructive pulmonary disease onset and pulmonary hypertension. The results will identify those who might benefit from multi-disciplinary follow-up to ensure interventions are employed to delay the onset of COPD and manage longer term cardiovascular problems.