Mulin Feng1, Zhaowei Yang1, Liying Pan1, Xuxin Lai2, Mo Xian1, Xiafei Huang1, Yan Chen3, Paul C Schröder4, Marjut Roponen5, Bianca Schaub4, Gary W K Wong6, Jing Li7. 1. Department of Allergy and Clinical Immunology, State Key Laboratory of Respiratory Disease, The First Affiliated Hospital, Guangzhou Medical University, Guangzhou, China. 2. Research Asia Pacific, ALK A/S, Hong Kong, China. 3. Department of Internal Medicine, Guangdong Pharmaceutical University, Guangzhou, China. 4. University Children's Hospital Munich, Department of Pulmonary and Allergy, LMU Munich, Munich, Germany; German Center for Lung Research (DZL), Munich, Germany. 5. Department of Environmental Science, University of Eastern Finland, Kuopio, Finland. 6. Department of Paediatrics, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China. 7. Department of Allergy and Clinical Immunology, State Key Laboratory of Respiratory Disease, The First Affiliated Hospital, Guangzhou Medical University, Guangzhou, China; Guangdong Provincial Key Laboratory of Allergy & Clinical Immunology, Guangzhou Medical University, Guangzhou, China. Electronic address: lijing@gird.cn.
Abstract
BACKGROUND: Environmental factors may play important roles in asthma, but findings have been inconsistent. OBJECTIVE: The goal of this study was to determine the associations between early life exposures, environmental factors, and asthma in urban and rural children in southeast China. METHODS: A screening questionnaire survey was conducted in 7,164 children from urban Guangzhou and 6,087 from rural Conghua. In the second stage, subsamples of 854 children (419 from Guangzhou, 435 from Conghua) were recruited for a case-control study that included a detailed questionnaire enquiring on family history, early life environmental exposures, dietary habits, and laboratory tests (including histamine airway provocation testing, skin prick tests, and serum antibody analyses). House dust samples from 76 Guangzhou families and 80 Conghua families were obtained to analyze levels of endotoxins, house dust mites, and cockroach allergens. RESULTS: According to the screening survey, the prevalence of physician-diagnosed asthma was lower in children from Conghua (3.4%) than in those from Guangzhou (6.9%) (P < .001). A lower percentage of asthma was reported in rural subjects compared with urban subjects (2.8% vs. 29.4%; P < .001) in the case-control study. Atopy (OR, 1.91 [95% CI, 1.58-2.29]), parental atopy (OR, 2.49 [95% CI, 1.55-4.01]), hospitalization before 3 years of age (OR, 2.54 [95% CI, 1.37-4.70]), high consumption of milk products (OR, 1.68 [95% CI, 1.03-2.73]), and dust Dermatophagoides farinae group 1 allergen (OR, 1.71 [95% CI, 1.34-2.19]) were positively associated with asthma. Living in a crop-farming family at < 1 year of age (OR, 0.15 [95% CI, 0.08-0.32]) and dust endotoxin levels (OR, 0.69 [95% CI, 0.50-0.95]) were negatively associated with asthma. CONCLUSIONS: Rural children from an agricultural background exhibited a reduced risk of asthma. Early life exposure to crop farming and high environmental endotoxin levels might protect the children from asthma in southern China.
BACKGROUND: Environmental factors may play important roles in asthma, but findings have been inconsistent. OBJECTIVE: The goal of this study was to determine the associations between early life exposures, environmental factors, and asthma in urban and rural children in southeast China. METHODS: A screening questionnaire survey was conducted in 7,164 children from urban Guangzhou and 6,087 from rural Conghua. In the second stage, subsamples of 854 children (419 from Guangzhou, 435 from Conghua) were recruited for a case-control study that included a detailed questionnaire enquiring on family history, early life environmental exposures, dietary habits, and laboratory tests (including histamine airway provocation testing, skin prick tests, and serum antibody analyses). House dust samples from 76 Guangzhou families and 80 Conghua families were obtained to analyze levels of endotoxins, house dust mites, and cockroach allergens. RESULTS: According to the screening survey, the prevalence of physician-diagnosed asthma was lower in children from Conghua (3.4%) than in those from Guangzhou (6.9%) (P < .001). A lower percentage of asthma was reported in rural subjects compared with urban subjects (2.8% vs. 29.4%; P < .001) in the case-control study. Atopy (OR, 1.91 [95% CI, 1.58-2.29]), parental atopy (OR, 2.49 [95% CI, 1.55-4.01]), hospitalization before 3 years of age (OR, 2.54 [95% CI, 1.37-4.70]), high consumption of milk products (OR, 1.68 [95% CI, 1.03-2.73]), and dust Dermatophagoides farinae group 1 allergen (OR, 1.71 [95% CI, 1.34-2.19]) were positively associated with asthma. Living in a crop-farming family at < 1 year of age (OR, 0.15 [95% CI, 0.08-0.32]) and dust endotoxin levels (OR, 0.69 [95% CI, 0.50-0.95]) were negatively associated with asthma. CONCLUSIONS: Rural children from an agricultural background exhibited a reduced risk of asthma. Early life exposure to crop farming and high environmental endotoxin levels might protect the children from asthma in southern China.
Authors: Niharika P Patel; Anna E Prizment; Bharat Thyagarajan; Evan Roberts; Heather H Nelson; Timothy R Church; DeAnn Lazovich Journal: Ann Allergy Asthma Immunol Date: 2018-04-06 Impact factor: 6.347
Authors: Anne M Riederer; Jennifer E Krenz; Maria I Tchong-French; Elizabeth Torres; Adriana Perez; Lisa R Younglove; Karen L Jansen; David C Hardie; Stephanie A Farquhar; Paul D Sampson; Nervana Metwali; Peter S Thorne; Catherine J Karr Journal: Indoor Air Date: 2021-07-19 Impact factor: 5.770