Breastfeeding and timing of first dietary introduction in relation to childhood asthma, allergies, and airway diseases: A cross-sectional study.
OBJECTIVE
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.
a Department of Building Environment and Energy Engineering , School of Environment and Architecture, University of Shanghai for Science and Technology , Shanghai , China.
Chen
C
Huang
a Department of Building Environment and Energy Engineering , School of Environment and Architecture, University of Shanghai for Science and Technology , Shanghai , China.
Wei
http://orcid.org/0000-0001-9863-4332
W
Liu
a Department of Building Environment and Energy Engineering , School of Environment and Architecture, University of Shanghai for Science and Technology , Shanghai , China.
Jiao
J
Cai
b Independent Researcher , Colts Neck , New Jersey , USA.
Louise B
LB
Weschler
a Department of Building Environment and Energy Engineering , School of Environment and Architecture, University of Shanghai for Science and Technology , Shanghai , China.
Xueying
X
Wang
a Department of Building Environment and Energy Engineering , School of Environment and Architecture, University of Shanghai for Science and Technology , Shanghai , China.
Yu
Y
Hu
a Department of Building Environment and Energy Engineering , School of Environment and Architecture, University of Shanghai for Science and Technology , Shanghai , China.
Zhijun
Z
Zou
a Department of Building Environment and Energy Engineering , School of Environment and Architecture, University of Shanghai for Science and Technology , Shanghai , China.
Li
L
Shen
a Department of Building Environment and Energy Engineering , School of Environment and Architecture, University of Shanghai for Science and Technology , Shanghai , China.|c Department of Building Science , Tsinghua University , Beijing , China.
Jan
J
Sundell
D000367:Age Factors; D001249:Asthma / Q000453:epidemiology; D001942:Breast Feeding / Q000706:statistics & numerical data*; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D003430:Cross-Sectional Studies; D004485:Eczema / Q000453:epidemiology; D005260:Female; D005638:Fruit; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D011014:Pneumonia / Q000453:epidemiology; D012135:Respiratory Sounds; D012140:Respiratory Tract Diseases / Q000453:epidemiology*; D012220:Rhinitis / Q000453:epidemiology; D006255:Rhinitis, Allergic, Seasonal / Q000453:epidemiology; D012737:Sex Factors; D012959:Socioeconomic Factors; D014675:Vegetables
Allergy; China; breastfeeding; pneumonia; preschool children