Clinical risk factors at 3 months of age for the development of bronchial asthma at 36 months of age.

BACKGROUND: We examined the associations between factors evident at the routine 3-month well-child visit (WCV) and the risk of developing 36-month parent-reported physician-diagnosed bronchial asthma (BA). METHODS: This longitudinal study was conducted in Nagoya City, Japan, and included 40,242 children who qualified for the 3-month WCVs in the city between April 1, 2016 and March 31, 2018. In total, 22,052 (54.8%) questionnaires linked to their 36-month WCVs were analyzed. RESULTS: The prevalence of BA was 4.5%. The multivariable Poisson regression model identified male sex (adjusted risk ratio [aRR], 1.59; 95% confidence interval [CI]: 1.40-1.81), born in autumn (aRR, 1.30; 95% CI: 1.09-1.55), having at least one sibling (aRR, 1.31; 95% CI: 1.15-1.49), wheeze history before 3-month WCVs, with clinic/hospital visit: aRR, 1.99; 95% CI: 1.53-2.56; hospitalization: aRR, 2.99; 95% CI: 2.09-4.12, eczema with itch (aRR, 1.51; 95% CI: 1.27-1.80), paternal history of BA (aRR, 1.98; 95% CI: 1.66-2.34), maternal history of BA (aRR, 2.11; 95% CI: 1.77-2.49), and rearing pets with fur (aRR, 1.35; 95% CI: 1.15-1.58) were independent risk factors for BA at 36 months of age. The combination of severe wheeze history (with clinic/hospital visit or hospitalization) and maternal and paternal BA could identify high-risk infants whose prevalence of BA was 20%. CONCLUSIONS: The combined assessment of important clinical factors enabled us to identify high-risk infants set to derive optimal benefit from health guidance provided to the parent or caregiver of the child or infant at WCVs.

Prevalence of infantile wheezing and eczema in a metropolitan city in Japan: A complete census survey.

Infantile wheezing and eczema are associated with the subsequent onset of asthma and other atopic diseases. However, there are no large population-based surveys on infantile allergic symptoms in Japan. The objective of the study was to determine the prevalence of wheezing and asthma in infants in Nagoya, Japan. This population-based cross-sectional study was performed in the metropolitan city of Nagoya, Japan. We surveyed parents to ascertain the prevalence of wheezing and eczema in infants who attended group health checkups at 3, 18, and 36 months of age. Their parents completed modified questionnaires from the International Study of Asthma and Allergies in Childhood. More than 90% of the approximately 40,000 children in each study group living in the target area were included in the survey. The prevalence of wheezing was 8%, 17%, and 13% at 3, 18, and 36 months, respectively, and was characterized by birth season. The prevalence of eczema was 24%, 30%, and 31%, at 3, 18, and 36 months, respectively. Participants born in autumn and winter had a higher incidence of eczema in each age group. Three-quarters of the children had a parental history of allergic conditions. Parental allergic diseases and male gender are risk factors for wheezing and eczema in children. This survey had a high response rate and covered almost the entire population of the target age groups in a large city. We believe that the results of this study, therefore, provide a much higher level of confidence regarding the prevalence of allergies in infants in Japan than that in previous studies with limited cohorts.

Development of a prediction model for infants at high risk of food allergy.

BACKGROUND: Identification of risk factors for food allergy (FA) in infants is an active research area. An important reason is to identify optimal target infants for early introduction of specific food antigens. Although eczema has been used for this purpose, multivariable prediction scores have not been reported. OBJECTIVE: The aim of this research is to develop a multivariable prediction score for infants at high risk of FA. METHODS: We performed a cross-sectional analysis of a self-administered questionnaire for the parents of 18-month-old children at well-child visits between April 2016 and March 2017 (development dataset) and between April 2017 and March 2018 (validation dataset). We developed and validated the prediction score. RESULTS: The questionnaire collection rate was 18,549 of 20,198 (92%) in the development dataset and 18,620 of 19,977 (93%) in the validation dataset. Risk factors for FA were being born in August-December, first child, eczema, atopic dermatitis in father and mother, and FA in mother and sibling(s). For identifying infants with FA, the developed multivariable prediction score showed higher discrimination ability (area under the curve [AUC] = 0.75) than focusing on eczema (AUC = 0.70) in the validation dataset. The score was also useful for identifying infants with a history of anaphylaxis (AUC = 0.73) than focusing on eczema (AUC = 0.67) in the validation dataset. CONCLUSION: The new prediction score enables more efficient identification of infants at high risk of FA, who may be the optimal target group for the early introduction of specific antigens.

Prevalence and associated factors of wheeze in early infancy.

BACKGROUND: The aim of this study was to assess the prevalence of wheeze in early childhood and to characterize associated factors for wheeze that could identify potentially feasible interventions for the future prevention of wheeze. METHODS: We performed a cross-sectional analysis of the data from the International Study of Asthma and Allergies in Childhood (ISAAC)-modified self-administered questionnaire of parents of 4-month-old infants at well-child visits (mandatory health check-ups) in Nagoya City, Japan, between April 2016 and March 2017 (development dataset) and between April 2017 and March 2018 (validation dataset). We used a multivariable, multilevel analysis to identify significant (P < 0.05), associated factors (Bonferroni correction was applied as necessary) after adjustment for local outbreaks of virus-transmitted diseases, access to medical facilities, and socioeconomic status. RESULTS: Among the 20 362 questionnaires given to families of infants living in Nagoya City (development dataset), 19 104 questionnaires (93.8%) were analyzed after data cleaning. In all, 1,446 (7.6%) infants experienced wheeze at least once within 4 months of age, 991 (5.2%) visited the clinic/hospital with wheeze, and 244 (1.3%) underwent hospitalization at that time. In the multilevel, multivariable model for hospitalization with wheeze, significant associated factors were male sex (adjusted odds ratio 1.8; 95% confidence interval 1.4-2.3), maternal current smoking (3.3; 2.0-5.5), and having at least one sibling (3.0; 2.2-4.1). These factors were also associated with wheeze and clinic/hospital visit with wheeze, and the results were confirmed in the validation dataset. CONCLUSIONS: Our study highlights that smoking cessation among mothers and improved hand hygiene at home are two interventions that could potentially decrease wheeze in early infancy.

[States and predictors of postpartum smoking relapse: a population based longitudinal study].

Objectives　Although more than half of women who smoke attempt to stop smoking after conception, many relapse after delivery. We conducted a population-based longitudinal study to identify the predictors of postpartum smoking relapse.Methods　Participants were expectant mothers living in Nagoya city, Japan, who notified Health Centers of their pregnancy from April 2014 to March 2015. A self-administered questionnaire was given to the expectant mothers that includes individual factors in the pregnancy: expectant mother's smoking status, age, marital status, experience of parturition, (mother's and father's) occupations, infertility treatment reception, feelings when pregnancy was confirmed, plans to return to parents' house for delivery, accessibility to help with childcare, household member(s) smoking in the same room, alcohol consumption, and depressive symptoms continuing more than 2 weeks.　We followed their smoking status at their children's "3-month-old health check-up" (3 months) and "1-year-and-6-months-old health check-up" (18 months) held in Health Centers until March 2017.　The data were analyzed using a combination of Chi-square or Fisher's exact test and logistic regression modeling. The analyses were conducted separately in primiparas and multiparas in addition to all expectant mothers.Results　Participants were 24,413 mothers; 18,041 were followed up at 3 months and 14,163 at 18 months.　Of the 18,041 mothers at 3 months, 1,031 primiparas and 695 multiparas stopped smoking when they confirmed pregnancy; 89 (8.6%) primiparas and 107 (15.4%) multiparas relapsed at 3 months. Of the 14,163 mothers at 18 months, 789 primiparas and 568 multiparas stopped smoking when they confirmed pregnancy; 155 (19.6%) primiparas and 174 (30.6%) multiparas relapsed smoking at 18 months.　As a result of logistic regression modeling, "multiparas," "younger (<25 years old)," "not married (only in multiparas)," "no plan to return to mother's parent's house for delivery," "household member(s) smoking in the same room (only in primiparas)," and "depressive symptoms (only in all mothers and primiparas)" were the predictors of postpartum smoking relapse at 3 months. "Multiparas," "not married (only in all mothers)," "no help with childcare (only in all mothers)," and "household member(s) smoking in the same room" were the predictors of postpartum smoking relapse at 18 months.Conclusion　More mothers relapsed with smoking after 3 months than before 3 months. The predictors of postpartum smoking relapse differed between 3 and 18 months. Support to continue smoking cessation was needed for each mother at an appropriate time not only in pregnancy but also after delivery.

Novel genetic variants of Anaplasma phagocytophilum, Anaplasma bovis, Anaplasma centrale, and a novel Ehrlichia sp. in wild deer and ticks on two major islands in Japan.

Wild deer are one of the important natural reservoir hosts of several species of Ehrlichia and Anaplasma that cause human ehrlichiosis or anaplasmosis in the United States and Europe. The primary aim of the present study was to determine whether and what species of Ehrlichia and Anaplasma naturally infect deer in Japan. Blood samples obtained from wild deer on two major Japanese islands, Hokkaido and Honshu, were tested for the presence of Ehrlichia and Anaplasma by PCR assays and sequencing of the 16S rRNA genes, major outer membrane protein p44 genes, and groESL. DNA representing four species and two genera of Ehrlichia and Anaplasma was identified in 33 of 126 wild deer (26%). DNA sequence analysis revealed novel strains of Anaplasma phagocytophilum, a novel Ehrlichia sp., Anaplasma centrale, and Anaplasma bovis in the blood samples from deer. None of these have been found previously in deer. The new Ehrlichia sp., A. bovis, and A. centrale were also detected in Hemaphysalis longicornis ticks from Honshu Island. These results suggest that enzootic cycles of Ehrlichia and Anaplasma species distinct from those found in the United States or Europe have been established in wild deer and ticks in Japan.