A cohort study on the influence of the chronic diseases on activities of daily living of the elderly aged 65 years and over in China / 中华流行病学杂志

Objective: To understand the influence of chronic diseases on the risk of impaired activities of daily living (ADL) of the elderly. Methods: Baseline data of 10 501 elderly individuals recruited by the Chinese Longitudinal Healthy Longevity Survey in 2002 were used, and follow up for this population was conducted until 2014. Cox Proportional Hazard Model was used to estimate the hazards ratios (HR) for the associations between five kinds of chronic diseases, the number of chronic diseases and the risk of ADL impairment in different age groups of the elderly. Results: Hypertension increased the risk of ADL impairment in the elderly of all age groups, which increased the ADL impaired risk by 43% (HR=1.43, 95%CI: 1.14-1.79) in group aged 65-74 years, 21% (HR=1.21, 95%CI: 1.02-1.43) in group aged 75-89 years and 20% (HR=1.20, 95%CI: 1.02-1.43) in group aged 90-105 years, respectively. Diabetes and cerebrovascular disease increased the ADL impaired risk by 102%(HR=2.02, 95%CI: 1.29-3.17), and 79% (HR=1.79, 95%CI: 1.24-2.58) in group aged 65-74 years, respectively. 'Suffering from one chronic disease' increased the ADL impaired risk by 13% (HR=1.13, 95%CI: 1.02-1.25), and suffering from two or more chronic diseases increased the ADL impaired risk by 25% (HR=1.25, 95%CI: 1.13-1.40) in all the age groups. Suffering from two or more chronic diseases increased the ADL impaired risk by 50% (HR=1.50, 95%CI: 1.21-1.87) in group aged 65-74 years and 17% (HR=1.17, 95%CI: 1.01-1.38) in groups aged 75-89 years. Conclusions: Hypertension was one of the most important risk factors for the impaired ADL in the elderly population in all age groups. Hypertension, diabetes, cerebrovascular disease or comorbidity increased the risk of impaired ADL in group aged 65-74 years.

Associations between maternal exposure to chemical fertilizers during pregnancy and the risk of offspring's low birth weights / 中华流行病学杂志

Objective: To explore the association between the consumption of chemical fertilizers and the risk of low birth weight (LBW), to provide references for prevention programs on LBW and to improve the birth outcomes. Methods: Stratified multivariate logistic regression method was used in this study involving 153 preterm LBW infants, 179 term LBW infants and 204 normal control infants that were randomly selected from the birth monitoring data between October 2007 and September 2012 in Pingding county, Shanxi province. Associations between the risk of LBW and maternal exposure to chemical fertilizers during pregnancy were identified. A normal control group was set up to compare results between preterm and term LBW groups. Results: Totally, 18 749 infants were born between 2007 and 2012, with the total incidence rates of LBW as 48.5‰, preterm LBW as 19.4‰, and term LBW as 29.1‰. Concerning the case control study on preterm LBW, after adjustment for confounding factors, the risk of preterm LBW appeared 2.51 (95%CI: 1.05-5.99) times higher in villages with annual consumption of chemical fertilizer ≥100 tons than those villages that using chemical fertilizer less than 50 tons. No significant statistical associations were found between the amounts of household chemical fertilizer consumption and the risks of preterm LBW. Regarding the case control study on term LBW, after adjustment for confounding factors, in villages with ≥100 tons annual consumption of chemical fertilizers, the risk of term LBW was 4.03 (95%CI: 1.63-9.92) times of the risk in villages where the annal use of chemical fertilizers was less than 50 tons. There was no significant association between household consumption of chemical fertilizers and the risk of term LBW. Conclusions: Maternal exposure to chemical fertilizers during pregnancy was associated with the risk of LBW. Our findings suggested that the amount of chemical fertilizer consumption in rural areas seemed also associated with the risks of other adverse pregnancy outcomes. Women should avoid the chance of exposure to chemical fertilizers during pregnancy and the consumption of chemical fertilizers should be carefully managed.