Sex differences in the association between smoking exposure and prevalence of wheeze and asthma in 3-year-old children.

OBJECTIVE: We examined independent and joint associations between prenatal and postnatal smoking exposure and the prevalence of wheeze and asthma among 3-year-old Japanese children. Sex differences were also investigated. METHODS: Smoking exposure, allergic symptoms, and potential confounding factor data were collected using a self-administered questionnaire. Wheeze was defined on the basis of the International Study of Asthma and Allergies in Childhood criteria. Physician-diagnosed asthma was considered to be present if a physician had diagnosed the child with asthma any time before the survey was administered. RESULTS: There were 6402 pediatric participants in this study. Maternal smoking throughout pregnancy and household smoking exposure during the first year of life were associated with an increased prevalence of wheeze among girls but not boys (adjusted odds ratio (OR) [95% CI] = 2.00 [1.13-3.42] and 1.34 [1.07-1.68], respectively). Girls exposed to both prenatal maternal smoking and postnatal household smoking exposure had a significantly higher prevalence of wheeze and physician-diagnosed asthma compared with girls without these exposures (adjusted OR [95% CI] = 2.06 [1.39-3.01] and 1.86 [1.01-3.26], respectively). No association was observed between perinatal smoking exposure and the prevalence of wheeze or asthma among boys. Significant interactions between sex and smoking exposure affecting wheeze and asthma were also found (p for interaction = 0.0003 and 0.01, respectively). CONCLUSION: We found a positive association between perinatal smoking exposure and the prevalence of wheeze and asthma only among girls. Effects of perinatal smoking exposure on wheeze and asthma might be sex specific. Further research is required.

Perinatal maternal depressive symptoms and risk of behavioral problems at five years.

BACKGROUND: Evidence on the association between perinatal maternal depression and children's behavioral development is limited. We investigated the association between maternal depressive symptoms during pregnancy and postpartum and the risk of childhood behavioral problems using data from a birth cohort study. METHODS: Study subjects were 1199 mother-child pairs. Maternal depressive symptoms were assessed with the Center for Epidemiologic Studies Depression Scale during pregnancy and the Edinburgh Postnatal Depression Scale at 4 months postpartum. Children's behavioral development at 5 years of age was assessed with the Strengths and Difficulties Questionnaire. RESULTS: Compared with children whose mothers did not experience depressive symptoms during pregnancy, those whose mothers did experience depressive symptoms during pregnancy had increased risk of emotional symptoms, conduct problems, hyperactivity, peer problems, and low prosocial behavior. Maternal depressive symptoms at around 4 months postpartum were associated with increased risk of childhood emotional problems. Compared with children whose mothers did not experience depressive symptoms during the perinatal period, those whose mothers did experience depressive symptoms both during pregnancy and postpartum had a fivefold increased risk of childhood emotional symptoms and a threefold increased risk of peer problems. CONCLUSIONS: Our findings suggest that perinatal maternal depression is associated with behavioral problems in children. IMPACT: Several epidemiological studies in Western countries have examined the association between perinatal maternal depression and children's behavioral development, yet the results are conflicting and inconclusive. There is limited evidence on this topic in Asia. In our study using data from a prospective pregnancy birth cohort, maternal depressive symptoms around 4 months postpartum were associated with an increased risk of emotional symptoms in children aged 5 years. Children whose mothers had exhibited depressive symptoms both during pregnancy and postpartum had a fivefold increased risk of childhood emotional symptoms and a threefold increased risk of peer problems.