Presented at the Neonatal Society 2008 Spring Meeting.
Lum S1, Kirkby J1, Welsh L1, Marlow N2, Costeloe K3, Stocks J1
1 Portex Respiratory Unit, UCL Institute of Child Health, London, UK
2 Queens Medical Centre, Nottingham, UK
3 Barts and the London School of Medicine and Dentistry, London, UK
Background: Among survivors of the 1995 UK EPICure cohort (GA < 26 weeks), 74% remained in O2 at 36 weeks postmenstrual age with persistent respiratory morbidity at 2.5 and 6 years of age (1). In addition to spirometry undertaken in schools in the national cohort, a subgroup of children was invited to participate in a focussed respiratory follow-up at the Institute of Child Health.
Aims: The aims of this study was to determine the extent and profile of functional respiratory status at 11 years in these extremely preterm (EP) children compared to matched term controls (TC) and to confirm the validity of lung function data collected in schools.
Methods: Measurements of plethysmographic lung volume (FRC) and specific resistance, Multiple Breath Washout (LCI [lung clearance index]) and Spirometry (forced vital capacity, forced expired volume and flows [FVC, FEV1, FEF]) were undertaken by all children.
Results: The 86 children (47 EP,11.2 y;39 TC,10.9 y) who successfully completed all tests were representative of the whole cohort tested at school (186 EP;160 TC). At time of test, EP children were shorter and lighter [Mn (SD) height and weight z-scores: -0.42 (0.92) and -0.23 (1.25) in EP vs. 0.48 (0.93) and 0.54 (1.02) in TC; (p<0.01)]. 51% EP children had a history of wheeze and 32% had current wheeze compared to 18% and 13% respectively in TC. Among EP children, 72% were classified as having bronchopulmonary dysplasia (BPD). A diagnosis of asthma had been made in 38% EP children with BPD, 31% in EP with no BPD and 26% in TC children.
LCI and specific resistance were significantly higher and all Spirometry variables lower both when the entire EP group was compared with term controls (data not shown), as well as when comparisons were limited to the subgroup of EP children with prior BPD (see table). Amongst the EP group, those with prior BPD had significantly lower FVC and FEV1 than those without.
Conclusion: These data confirm and extend results obtained during school spirometry. The continuing symptoms of wheeze together with the significantly diminished lung function in EP children at 11 years, particularly in those with history of BPD, make it imperative to follow-up the longer term effects of neonatal lung disease through adolescence into adult life.
Acknowledgements: Funded by the Medical Research Council, UK.
References
1. Marlow N N Engl J Med 2005; 352:9-19.
2. Stanojevic S Am J Respir Crit Care Med 2008; 177:253-260.