Perinatal inflammation relates to early respiratory morbidity and lung function at 12 years of age in children born very preterm.

Abstract

Very preterm birth may be associated with lung function impairment later in life. It is not known if this is caused by prematurity per se or by associated perinatal events, such as maternal-foetal inflammation and severity of early neonatal lung disease. We assessed these factors in a prospective cohort of very preterm infants followed from birth to middle school age. In 71 infants with a gestational age of median 27.4 (range 23.9-31.7) weeks, pro-inflammatory and modulatory cytokines were measured in umbilical cord blood and in arterial blood sampled at 6, 24 and 72h after birth, and cumulated cytokine concentrations were calculated as area under the curve (AUC). At median 12.6 (range 12.3-13.5) years of age, pulmonary function testing was done in 53 children. There was a positive correlation between days on mechanical ventilation and AUC for IL-6 (p=0.001), IL-8 (p=0.015) and IL-10 (p=0.006). Infants with bronchopulmonary dysplasia (BPD; n=32) had higher AUC for the cytokines IL-6, IL-8 and IL-10 than those without BPD (all p<0.01). Higher levels of AUC for IL-6 at birth correlated with lower forced expiratory volume in 1s (p=0.030) and lower mean expiratory flow rate between 25 and 75% of forced vital capacity (p=0.034). Perinatal inflammation, assessed by circulating cytokines in the first three days of life, was associated with BPD and with airway obstruction at 12years of age.