Search

It is difficult to evaluate long‐term ventilation and indoor‐outdoor temperature variation on‐site in the birth residence so as to investigate their associations with learning capacity from childhood through adolescence. Here, we conducted a questionnaire‐based retrospective cohort study in ten schools from two northeast China cities with warm summers and severe cold winters when residences had very low air exchange rates. Scores for Chinese, Mathematics, and English in the final exams of the summer semester in June 2018 were collected to evaluate learning capacity. We surveyed 6238 students aged 14.7 (SD: 2.1) years old. Using the 2nd quarter (April‐May‐June) birth as reference, 4th quarter (October‐November‐December) birth consistently was significantly associated with lower scores in Chinese in bivariate (β, 95%CI: −3.2, −4.3 to −2.0) and multivariate (−1.8, −2.4 to −0.8) linear regression analyses. Stratified sub‐analyses showed significant associations for male (−2.4, −3.7 to −1.1), urban (−2.4, −3.4 to −1.4), and primary students (−2.9, −4.5 to −1.4). Since household ventilation and indoor‐outdoor temperature variation had great differences between the 2nd and 4th quarter of year, our results suggest that these two factors in the birth residence could be associated with learning capacity in childhood, especially for male and primary students in northeast China. [ABSTRACT FROM AUTHOR]

From October 2010 to April 2012, we conducted a cross‐sectional study of associations between household environments and childhood health among preschool children in eight Chinese cities. Here, we analyze associations of early household renovation with preterm birth (PTB), low birthweight (LBW), term low birthweight (Term‐LBW), and small for gestational age (SGA). Parents responded to questions about household renovation and their children's gestational age and birthweight. In the multivariate logistic regression analyses, household renovation in the year before pregnancy was significantly associated with LBW (sample size: N = 25 813; adjusted odds ratio (OR) with 95% confidence intervals (CIs): 1.23, 1.01‐1.50) and Term‐LBW (N = 24 823; 1.29, 1.01‐1.67). Household renovation during pregnancy was significantly associated with PTB (N = 25 202; 1.28, 1.01‐1.69). These significant associations were also found in the two‐level (city‐child) logistic regression analyses and in the sensitivity analyses among 21 009 children with complete data in all studied variates. Stronger associations were found in certain subgroups. Our findings indicate that household renovation within one year before pregnancy might be a risk factor for LBW and Term‐LBW, while household renovation during pregnancy could be a risk factor for PTB. [ABSTRACT FROM AUTHOR]

This study investigated the association of building characteristics and occupant behaviours with building dampness indicators. Data were from a cross-sectional study in urban Tianjin and rural Cangzhou, China, from 2013 to 2014. We studied two fundamental types of Chinese dwellings: bungalows typical of rural locales and apartments in low- and high-rise buildings typical of urban settings. Occupants of bungalows reported more dampness indicators than apartment dwellers. Risk factors for one or more dampness indicators included natural ventilation without fans, older dwellings and coal stove or Kang heating system (a brick bed installed in the bedroom for heating and sleeping). All these factors were typical of bungalows, which generally used older building technologies including non-insulated external walls, wooden frame windows, electric fans for cooling and no exhaust fan ventilation. Occupant behaviours that decreased the risk for dampness indicators included frequent window opening and daily cleaning, regardless of the type of dwelling. Indoor dampness was highly correlated with mouldy and humid odour, and paradoxically (although not a new finding) with the perception of air dryness. [ABSTRACT FROM AUTHOR]

Objectives: We investigated associations of breastfeeding (BF) durations and patterns and of timing of other dietary introductions with prevalence of asthma, wheeze, hay fever, rhinitis, pneumonia, and eczema among preschool children.Methods: During April 2011-April 2012, we conducted a cross-sectional study in 72 kindergartens from five districts of Shanghai, China and obtained 13,335 questionnaires of children 4–6-years-old. We used multiple logistic regression models to evaluate the target associations.Results: Compared to children who were never BF, children who were exclusively breastfed 3–6 months had the lowest risk of asthma (adjusted odds ratio and 95% confidence interval: 0.81, 0.72–0.91) and wheeze (0.93, 0.87–0.99); and exclusive BF >6 months was significantly associated with a reduced risk of hay fever (0.93, 0.89–0.97), rhinitis (0.97, 0.94–0.99), pneumonia (0.97, 0.94–0.99), and eczema (0.96, 0.93–0.99). No significant associations were found between time when fruits or vegetables were introduced and the studied diseases. Associations were independent of the child's sex and parent's ownership of the current residence. Longer duration BF was only significantly protective when there was no family history of atopy.Conclusions: This study suggests that heredity, but not sex and socioeconomic status, may negatively impact the effect of BF on childhood airway and allergic diseases. Our findings support China's national recommendation that mothers provide exclusive BF for the first four months, and continue partial BF for more than 6 months. [ABSTRACT FROM AUTHOR]