Chronic lung disease of prematurity and intrauterine growth retardation: a population-based study.
OBJECTIVE
To determine the risk of chronic lung disease (CLD) in small for gestational age (SGA) preterm infants in comparison to appropriately grown and large for gestational age (LGA) infants.


METHODS
Observational study derived from a geographically defined population (Trent Health Region, United Kingdom). All preterm infants of <or=32 completed weeks' gestation born to Trent resident mothers admitted to neonatal units between 1995 and 1999 (inclusive) were included. Birth weight percentiles were created for the whole population, and infants were classified as SGA infants (if <10th percentile), appropriately grown (if between 25th and 75th percentiles-reference group), and LGA infants (if >or=90th centile). Both mortality and CLD rates (using both 28 days' and 36 weeks' postmenstrual age [PMA] definitions) were determined for these groups of infants.


RESULTS
Four thousand fifty-one preterm infants <or=32 weeks' gestation were identified. SGA infants showed higher mortality before 28 days' postnatal age and 36 weeks' PMA as compared with reference group infants (odds ratio [OR]: 2.01, 95% confidence interval [CI]: 1.49-2.72; and OR: 2.00, 95% CI: 1.49-2.69), respectively. SGA infants showed a significantly greater risk of developing CLD, both at 28 days' and 36 weeks' PMA as compared with the reference group infants (OR: 1.34, 95% CI: 1.03-1.74; and OR: 1.87, 95% CI: 1.39-2.51), respectively. LGA infants showed a trend toward a reduced incidence of CLD in comparison to the reference group, which was statistically significant for the 36 weeks' definition (OR: 0.76-28 weeks, 95% CI: 0.57-1.01; and OR: 0.55-36 weeks, 95% CI: 0.37-0.81).


CONCLUSIONS
Fetal growth seems to influence mortality in general and morbidity, attributable to CLD, in particular in preterm infants. SGA preterm infants are at higher risk of death before 28 days' and 36 weeks' PMA and CLD by both definitions. LGA infants show reduced risk of CLD.
Lal
Mithilesh K
MK
Neonatal Unit, Leicester Royal Infirmary, University Hospitals of Leicester, Leicester, United Kingdom. mithilesh.lal@doctors.org.uk
Manktelow
Bradley N
BN
Draper
Elizabeth S
ES
Field
David J
DJ
D001724:Birth Weight; D002908:Chronic Disease; D005260:Female; D005317:Fetal Growth Retardation / Q000453:epidemiology*; D005865:Gestational Age; D006801:Humans; D015994:Incidence; D007226:Infant Mortality; D007231:Infant, Newborn; D007235:Infant, Premature, Diseases / Q000453:epidemiology* / Q000401:mortality / Q000628:therapy; D007236:Infant, Small for Gestational Age; D019102:Infant, Very Low Birth Weight; D007363:Intensive Care Units, Neonatal; D007385:Intermittent Positive-Pressure Ventilation; D008171:Lung Diseases / Q000453:epidemiology* / Q000401:mortality / Q000628:therapy; D008297:Male; D011247:Pregnancy; D011446:Prospective Studies; D012121:Respiration, Artificial; D006113:United Kingdom / Q000453:epidemiology