Systematic review and meta-analysis of FEV1 in preterm born children

Abstract

<b>Introduction:</b> Decreased lung function is associated with preterm birth but there is paucity of information on geographical differences and if temporal improvements have occurred. <b>Aims and Objectives:</b> We systematically reviewed the literature to determine deficits in percentage predicted forced expiratory volume in 1s (%FEV₁) in preterm-born subjects including those with bronchopulmonary dysplasia (BPD) compared with term controls. We studied the effect of year of birth, age, introduction of surfactant therapy and geographical region of birth on %FEV₁ deficits. <b>Methods:</b> We searched 8 databases up to December 2021. Studies reporting mean %FEV₁ for preterm subjects, with or without a term control group were identified. Data were analysed using Review Manager and R Metafor package. <b>Results:</b> From 16,856 titles, 685 articles were screened: 86 with and without term controls were included. 50 with term controls were combined with 36 from our previous systematic review to include 7,094 preterm and 17,700 term subjects. 45, 29, and 26 studied preterms without BPD, BPD₂₈ and BPD₃₆ respectively and 86 studied preterms. Compared to the term group, the whole preterm group had deficit of -9.2% for %FEV₁; preterm without BPD and with BPD had -5.8% and -16% deficits respectively. As year of birth increased, the difference in mean %FEV1 between the preterms and terms for whole Preterm and 3 BPD groups significantly narrowed. For the whole BPD group, when compared to Scandinavian, North America and Western Europe had deficits of -5.5% and -4.1% respectively. <b>Conclusions:</b> %FEV1 was reduced in preterm-born survivors. %FEV₁ improved over recent years but geographical region had an effect on later %FEV1 for the BPD groups.