BACKGROUND: Although results of many studies have indicated an increased risk of asthma in former late preterm (LPT) infants, most of these studies did not fully address covariate imbalance. OBJECTIVE: To compare the cumulative frequency of asthma in a population-based cohort of former LPT infants to that of matched term infants in their early childhood, when accounting for covariate imbalance. METHODS: From a population-based birth cohort of children born 2002-2006 in Olmsted County, Minnesota, we assessed a random sample of LPT (34 to 36 6/7 weeks) and frequency-matched term (37 to 40 6/7 weeks) infants. The subjects were followed-up through 2010 or censored based on the last date of contact, with the asthma status based on predetermined criteria. The Kaplan-Meier method was used to estimate the cumulative incidence of asthma during the study period. Cox models were used to estimate the hazard ratio and 95% confidence interval for the risk of asthma, when adjusting for potential confounders. RESULTS: LPT infants (n = 282) had a higher cumulative frequency of asthma than did term infants (n = 297), 29.9 versus 19.5%, respectively; p = 0.01. After adjusting for covariates associated with the risk of asthma, an LPT birth was not associated with a risk of asthma, whereas maternal smoking during pregnancy was associated with a risk of asthma. CONCLUSION: LPT birth was not independently associated with a risk of asthma and other atopic conditions. Clinicians should make an effort to reduce exposure to smoking during pregnancy as a modifiable risk factor for asthma.
BACKGROUND: Although results of many studies have indicated an increased risk of asthma in former late preterm (LPT) infants, most of these studies did not fully address covariate imbalance. OBJECTIVE: To compare the cumulative frequency of asthma in a population-based cohort of former LPT infants to that of matched term infants in their early childhood, when accounting for covariate imbalance. METHODS: From a population-based birth cohort of children born 2002-2006 in Olmsted County, Minnesota, we assessed a random sample of LPT (34 to 36 6/7 weeks) and frequency-matched term (37 to 40 6/7 weeks) infants. The subjects were followed-up through 2010 or censored based on the last date of contact, with the asthma status based on predetermined criteria. The Kaplan-Meier method was used to estimate the cumulative incidence of asthma during the study period. Cox models were used to estimate the hazard ratio and 95% confidence interval for the risk of asthma, when adjusting for potential confounders. RESULTS: LPT infants (n = 282) had a higher cumulative frequency of asthma than did term infants (n = 297), 29.9 versus 19.5%, respectively; p = 0.01. After adjusting for covariates associated with the risk of asthma, an LPT birth was not associated with a risk of asthma, whereas maternal smoking during pregnancy was associated with a risk of asthma. CONCLUSION: LPT birth was not independently associated with a risk of asthma and other atopic conditions. Clinicians should make an effort to reduce exposure to smoking during pregnancy as a modifiable risk factor for asthma.
Authors: Jennifer L St Sauver; Brandon R Grossardt; Barbara P Yawn; L Joseph Melton; Walter A Rocca Journal: Am J Epidemiol Date: 2011-03-23 Impact factor: 4.897
Authors: C-I Wi; E A Krusemark; G Voge; S Sohn; H Liu; E Ryu; M A Park; J A Castro-Rodriguez; Y J Juhn Journal: Allergy Date: 2018-02-07 Impact factor: 13.146
Authors: Chung-Il Wi; Sunghwan Sohn; Mary C Rolfes; Alicia Seabright; Euijung Ryu; Gretchen Voge; Kay A Bachman; Miguel A Park; Hirohito Kita; Ivana T Croghan; Hongfang Liu; Young J Juhn Journal: Am J Respir Crit Care Med Date: 2017-08-15 Impact factor: 21.405
Authors: Wesley M Jackson; Thomas Michael O'Shea; Elizabeth N Allred; Matthew M Laughon; William Adam Gower; Alan Leviton Journal: Pediatr Pulmonol Date: 2018-08-29
Authors: Harsheen Kaur; Sunghwan Sohn; Chung-Il Wi; Euijung Ryu; Miguel A Park; Kay Bachman; Hirohito Kita; Ivana Croghan; Jose A Castro-Rodriguez; Gretchen A Voge; Hongfang Liu; Young J Juhn Journal: BMC Pulm Med Date: 2018-02-13 Impact factor: 3.317