Preterm infant growth and asthma at age 8 years.
OBJECTIVE
To examine associations of gain in body mass index (BMI) and linear growth from term to 18 months with asthma at age 8 years in a cohort of preterm infants. We hypothesised that rapid BMI gain would increase asthma risk, whereas rapid linear growth would be protective.


METHODS
Observational secondary analysis of data from the Infant Health and Development Program.


METHODS
8 centres in the USA.


METHODS
863 preterm (≤37 weeks), low birthweight (≤2500 g) children.
Gain in BMI and linear growth from term to 4 months, 4-12 months and 12-18 months, in z-scores.


METHODS
Asthma at age 8 years, assessed by parent report of the child ever receiving the diagnosis from a doctor.


RESULTS
At age 8 years, 149 (17%) had ever been diagnosed with asthma. Adjusting for maternal and child factors in logistic regression, for each additional z-score gain in BMI from term to 4 months, odds of asthma at age 8 years were higher (OR 1.3, 95% CI 1.1 to 1.5); findings were similar for BMI gain from 4-12 months. More rapid linear growth from term to 4 months was not associated with lower odds of asthma (OR 1.1, 95% CI 0.9 to 1.3), with similar findings for 4-12 months and 12-18 months.


CONCLUSIONS
More rapid BMI gain in the 1st year of life was associated with higher odds of asthma, whereas linear growth did not appear protective. Our results add to mounting evidence that excess weight gain after term may be harmful to preterm infants.
Department of Pediatric Newborn Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA.
Mandy B
MB
Belfort
Division of Pediatric Pulmonary and Allergy, Boston Medical Center, Boston, Massachusetts, USA.
Robyn T
RT
Cohen
Department of Pediatric Newborn Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA Division of Pulmonary and Respiratory Diseases, Boston Children's Hospital, Boston, Massachusetts, USA.
Lawrence M
LM
Rhein
Department of Neonatology, Beth Israel Deaconess Medical Center, Department of Social and Behavioral Sciences, Harvard School of Public Health, Boston, Massachusetts, USA.
Marie C
MC
McCormick
D001249:Asthma / Q000453:epidemiology*; D015992:Body Mass Index; D002648:Child; D005260:Female; D006801:Humans; D007230:Infant, Low Birth Weight / Q000254:growth & development; D007231:Infant, Newborn; D007234:Infant, Premature / Q000254:growth & development*; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D012307:Risk Factors; D014481:United States / Q000453:epidemiology
Epidemiology; Growth; Neonatology; Respiratory