Associations of Early Life Exposures and Environmental Factors With Asthma Among Children in Rural and Urban Areas of Guangdong, 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.

[Epidemiological investigation on major depressive disorder in the most heavily damaged areas from Wenchuan earthquake in 2008].

OBJECTIVE: To assess the prevalence, demographic characteristics, risk factors and protective factors on major depression disorder (MDD) among the affected people in the epicenter, 7 months after the 2008-earthquake in Wenchuan, China. METHODS: Stratified multistage cluster randomization was conducted to choose 14 503 subjects aged 15 years or over in the city of Dujiangyan, Beichuan county and Qingchuan county, Sichuan province. We used the general health questionnaire (GHQ-12) as the screening instrument, and the structured clinical interview for DSM-IV-TR axis I disorder-patient edition (SCID-I/P) as the tool for diagnosis. RESULTS: There were 180 persons diagnosed as MDD with other 13 asymptomatic ones. The point prevalence of MDD was 1.27% and the lifetime prevalence was 1.36%. Risk factors were including:being female (OR = 1.56, 95%CI: 1.136 ∼ 2.143, P < 0.05), co-morbidity with somatic diseases (OR = 4.02, 95%CI: 2.75 - 5.90, P < 0.05), wounded in the earthquake (OR = 3.29, 95%CI: 1.92 - 5.65, P < 0.05), property loss up to 10 000 - 20 000 Yuan (OR = 2.09, 95%CI: 1.18 - 3.69, P < 0.05), property loss up to > 20 000 Yuan (OR = 2.54, 95% CI: 1.38 - 4.68, P < 0.05), death or missing of family members (OR = 3.79, 95%CI: 2.08 - 6.89, P < 0.05) and in middle-age (OR = 2.31, 95%CI: 1.38 - 3.86, P < 0.05) etc. Having had a job seemed to be a protective factor (OR = 0.60, 95%CI: 0.43 - 0.83, P < 0.05). CONCLUSION: Major depressive disorder appeared to be a common psychiatric disease in these quake-stricken areas, that causing serious problems. Sustained follow-up and care provided to the affected people in these areas were of extreme importance.