ABSTRACT
Objective To carry out a quantitative estimate that related to the effects of shortterm exposure to PM2.5 on all-cause mortality and emergency visits in China by using the systematic review and Meta-analysis.Methods We selected all the studies published before March 2018 from China National Knowledge Infrastructure,Wanfang database,PubMed and EMBASE and data on relative risk (RR),excess risk (ER) and their 95％CIs:appeared in these papers were extracted.According to the differences in the size or direction (heterogeneity) of the results,we computed summary estimates of the effect values using a random-effect or fixed effect model.We also conducted the subgroup analysis and Meta-analysis to have assessed the selected studies for the evidence of study bias.Results A total of 33 original studies,indexed in databases,were identified.Among those studies,39 sets of data on mortality and 4 sets of data on emergency were valid to show that within the daily concentration range from 47.7 to 176.7 pg/m3,for 10 μg/m3 increases in PM2.5 concentrations,it would increase the daily numbers of deaths by 0.49％ (95％CI:0.39％-0.59％) and 0.30％ (95％CI:0.10％-0.51％) for all-cause deaths and all-cause emergency-room visits,respectively.For subgroup analysis,the combined effect of PM2.5 in causing short-term all-cause deaths in the northern areas (ER=0.42％,95％CI:0.30％-0.54％) seemed lower than that in the southern areas (ER=0.63％,95％CI:0.44％-0.82％).The combined effect of PM2.5 concentration below 75 μg/m3 (ER=0.50％,95％CI:0.37％-0.62％) was higher than that of PM25 concentration ≥75 μ g/m3 (ER=0.39％,95％ CI:0.26％-0.52％).Conclusion Within the concentration range from 47.7 to 176.7 μg/m3,short-term exposure to current level of PM2.5 might increase both the all-cause daily mortality and daily emergency visits in China.
ABSTRACT
Objective To carry out a quantitative estimate that related to the effects of shortterm exposure to PM2.5 on all-cause mortality and emergency visits in China by using the systematic review and Meta-analysis.Methods We selected all the studies published before March 2018 from China National Knowledge Infrastructure,Wanfang database,PubMed and EMBASE and data on relative risk (RR),excess risk (ER) and their 95％CIs:appeared in these papers were extracted.According to the differences in the size or direction (heterogeneity) of the results,we computed summary estimates of the effect values using a random-effect or fixed effect model.We also conducted the subgroup analysis and Meta-analysis to have assessed the selected studies for the evidence of study bias.Results A total of 33 original studies,indexed in databases,were identified.Among those studies,39 sets of data on mortality and 4 sets of data on emergency were valid to show that within the daily concentration range from 47.7 to 176.7 pg/m3,for 10 μg/m3 increases in PM2.5 concentrations,it would increase the daily numbers of deaths by 0.49％ (95％CI:0.39％-0.59％) and 0.30％ (95％CI:0.10％-0.51％) for all-cause deaths and all-cause emergency-room visits,respectively.For subgroup analysis,the combined effect of PM2.5 in causing short-term all-cause deaths in the northern areas (ER=0.42％,95％CI:0.30％-0.54％) seemed lower than that in the southern areas (ER=0.63％,95％CI:0.44％-0.82％).The combined effect of PM2.5 concentration below 75 μg/m3 (ER=0.50％,95％CI:0.37％-0.62％) was higher than that of PM25 concentration ≥75 μ g/m3 (ER=0.39％,95％ CI:0.26％-0.52％).Conclusion Within the concentration range from 47.7 to 176.7 μg/m3,short-term exposure to current level of PM2.5 might increase both the all-cause daily mortality and daily emergency visits in China.
ABSTRACT
Objective: To explore the relationship between glycemic control and visceral adiposity index (VAI) among type 2 diabetes mellitus (T2DM) patients.Methods: A community-based epidemiological field study for patients with T2DM aged ≥ 40 years was conducted in China.Every participant underwent physical examinations, biochemical tests of fasting glucose, glycosylated hemoglobin (HbA1c), total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C) and so on, and a questionnaire, including anthropometric characteristics, lifestyle, disease history, family history, and medication use.Those participants with HbA1c ≥7.0% were classified as the poorly controlled in our analysis of relationship between glycemic control and VAI.Anthropometric characteristics, lifestyle, and biochemical indexes of the participants were compared among the groups of different VAI levels.Logistic models were applied in multiple analysis adjusting for possible confounders.Results: A total of 1 607 patients with T2DM were recruited in our analysis with a mean age of (59.4±8.1) years and an average T2DM duration of (7.0±6.4) years.Among them, 78.3% were on hypoglycemic therapy.The cutoff points of quartiles of VAI were calculated for the males and females, respectively.According to the ascending order of the quartiles of VAI, the participants were divided into four groups, i.e.Q1, Q2, Q3, and Q4.The poor glycemic control rate for these groups were 60.6%, 65.7%, 70.1%, and 71.0%, respectively (Trend χ2=12.20, P<0.001).After adjustment for age, gender, systolic blood pressure (SBP), diastolic blood pressure (DBP), LDL-C, smoking, cardio-cerebral vascular disease (CVD) history, hypoglycemic therapy, T2DM duration, and family history of diabetes, the Logistic regression models showed that the glycemic control rate was significantly associated with VAI levels among the patients with T2DM.Compared with the participants in group Q1, the ORs of poor glycemic control for those in groups Q2, Q3, and Q4 were 1.239 (95%CI 0.918 to 1.672), 1.513 (95%CI 1.117 to 2.050), and 1.535 (95%CI 1.128to 2.088), respectively (trend P=0.003).With each quartile increase in VAI, the OR of poor glycemic control was 1.162 (95%CI 1.054 to 1.282).Conclusion: The glycemic control among the patients with T2DM is significantly associated with VAI.High level of VAI is an indicator of poor glycemic control.