Relationship between in utero C-reactive protein levels and asthma in at-risk children.

BACKGROUND: Asthma research has focused on postnatal exposures, but there is recent evidence to indicate atopic immune responses might be initiated in utero. Systemic inflammation during pregnancy might indicate an environment that could increase propensity in the child to develop allergic disease. OBJECTIVE: To investigate the association of systemic inflammation, as measured by C-reactive protein (CRP) levels, with asthma and wheezing in offspring within an at-risk, mostly Mexican, cohort. METHODS: Using data from a randomized education intervention of families at risk for asthma from 1998 followed through 2009 in urban Chicago, asthma was defined as ever having a physician diagnosis of asthma by 3 years of age and wheezing before the third year. Logistic regression models controlling for confounders investigated the effect of prenatal CRP levels on these outcomes. RESULTS: There were 244 mother-child pairs included in the study analysis with median prenatal CRP levels of 4.9 mg/L (interquartile range 3.2-7.7). Continuous prenatal CRP levels were predictive of asthma by year 3 (relative risk 2.4, 95% confidence interval 1.3, 3.6) and wheezing in year 3 (relative risk 1.7, 95% confidence interval 1.1, 2.4) after adjustment. Associations remained significant in mothers who were of Mexican ethnicity and were nonsmokers, suggesting that effects might be stronger in children at lower risk of disease. CONCLUSION: Prenatal CRP levels are associated with asthma by year 3 and wheezing in year 3 within a high-risk, urban, mostly Mexican, cohort. Maternal systemic inflammation might reflect a prenatal environment that could increase offspring susceptibility to develop wheezing and asthma young in life.

Relationship between prenatal antibiotic use and asthma in at-risk children.

BACKGROUND: Asthma prevalence has doubled in developed countries during the past 30 years. Pre- and perinatal events are essential in shaping the development of the immune system and systemic antibiotic use during this time could alter the maternal or placental microbiome, leading to an increase in the child's risk of developing asthma. OBJECTIVE: To determine whether prenatal antibiotic use is associated with asthma and wheezing in children at risk for asthma. METHODS: Using data from a randomized education intervention of families at risk for asthma from 1998 followed through 2009 in urban Chicago, asthma was defined as ever having a physician asthma diagnosis by year 3 and wheezing in the third year. Logistic regression models controlling for confounders investigated the effect of antibiotic use during pregnancy on these outcomes. RESULTS: After adjustment, prenatal antibiotic use was a risk factor for asthma (odds ratio 3.1, 95% confidence interval 1.4-6.8) but was only weakly associated with wheezing (odds ratio 1.8, 95% confidence interval 0.9-3.3). Analyses of the effects of timing of prenatal antibiotic use on asthma and wheezing showed the relation remained consistent for antibiotic use later in pregnancy, but the outcomes were not associated with antibiotic use in the first trimester. CONCLUSION: This study suggests prenatal antibiotic use might be associated with the development of asthma in children at risk for asthma. Although the relation with prenatal antibiotics does not hold for wheezing in this study, there might be a trend that could be delineated further within a larger cohort study.

The effect of low-cost modification of the home environment on the development of respiratory symptoms in the first year of life.

BACKGROUND: Previous studies have suggested that environmental exposures may be related to the development of respiratory symptoms in early life. Intervention studies, however, have not produced consistent findings. OBJECTIVE: The Peer Education in Pregnancy Study examined the effect of home environment intervention with pregnant women at risk for having children with asthma on the development of respiratory symptoms in their infants. METHODS: A total of 383 pregnant women whose unborn child had a first-degree relative with an allergic history were randomized to 1 of 2 intervention groups, both of whom received general health education, smoking cessation advice, and encouragement to breastfeed. In addition, the intensive education group received 3 home visits focused on home environment modification. Home assessment was performed at baseline and after 1 year of follow-up. Respiratory symptoms were identified during the first year of life. RESULTS: Families in both intervention groups showed significant changes in several environmental factors, with significant differences between the 2 groups in insects other than cockroaches, use of mattress covers, and washing in hot water. Children in the intensive education group had slightly lower incidence rates of respiratory symptoms, but few differences were statistically significant. CONCLUSIONS: The results of this study do not provide strong support for a primary intervention focused on general modification of the home environment during pregnancy for high-risk children. It does not address the effects of more aggressive approaches or of interventions targeting individual environmental factors.

Prenatal exposure to acetaminophen and respiratory symptoms in the first year of life.

BACKGROUND: Prevalence of asthma in developed countries increased between the 1970s and the 1990s. One factor that might contribute to the trends in asthma is the increased use of acetaminophen vs aspirin in children and pregnant women. OBJECTIVE: To examine relationships between in utero exposure to acetaminophen and incidence of respiratory symptoms in the first year of life. METHODS: A total of 345 women were recruited in the first trimester of pregnancy and followed up with their children through the first year of life. Use of acetaminophen in pregnancy was determined by questionnaire and related to incidence of respiratory symptoms. RESULTS: Use of acetaminophen in middle to late but not early pregnancy was significantly related to wheezing (odd ratio, 1.8; 95% confidence interval, 1.1-3.0) and to wheezing that disturbed sleep (odds ratio, 2.1; 95% confidence interval, 1.1-3.8) in the first year of life after control for potential confounders. CONCLUSION: This study suggests that use of acetaminophen in middle to late but not early pregnancy may be related to respiratory symptoms in the first year of life. Additional follow-up will examine relationships of maternal and early childhood use of acetaminophen with incidence of asthma at ages 3 to 5 years, when asthma diagnosis is more firmly established.