Prevalence, associated factors and patterns of multimorbidity of non-communicable diseases among adults in Shaanxi Province / 西安交通大学学报(医学版)

【Objective】 To estimate the prevalence, associated factors and patterns of multimorbidity of non-communicable diseases among adults in Shaanxi Province so as to provide evidence for the prevention and control of non-communicable diseases. 【Methods】 We used the data of adults aged 18 years and older collected in the baseline survey of Shaanxi Project in the Regional Ethnic Cohort Study in Northwest China. Multinomial logistic regression was used to explore the associated factors for multimorbidity. Exploratory factor analysis was used to extract patterns of multimorbidity. 【Results】 The prevalence of multimorbidity was 10.7% among the 44 442 participants. Age increase, being males, urban residence, and being overweight or obesity were positively associated with multimorbidity. Compared with women, men had a higher risk of multimorbidity. The OR and 95% CI was 1.25 (1.12-1.39). The risk of multimorbidity increased with age among adults. Compared with participants aged 18.0-34.9 years, the ORs and 95% CIs of those aged 35.0-44.9, 45.0-54.9, 55.0-64.9, and ≥65.0 years were 4.73 (3.47-6.46), 15.61 (11.60-21.00), 41.39 (30.76-55.70) and 90.04 (66.58-121.77), respectively. The primary multimorbidity patterns among adults in Shaanxi were cardiovascular-metabolic multimorbidity (5.4%), viscero-articular multimorbidity (1.0%), and respiratory multimorbidity (0.3%). 【Conclusion】 More than one in ten adults in Shaanxi Province had multimorbidity, and the predominant pattern of multimorbidity was cardiovascular-metabolic multimorbidity. The prevention and control of non-communicable diseases should be reinforced in middle-aged and older people, males, people living in the urban, and overweight or obese people. More attention should be paid to the prevention and control of cardiovascular-metabolic diseases.

Establishment of the data capture and management platform for case-control study on precocious puberty based on REDCap system / 西安交通大学学报(医学版)

【Objective】 To conduct a case-control study on precocious puberty as an example to introduce the establishment and design of the electronic Data capture and management platform using Research Electronic data Capture (REDCap) system and support the development of clinical research. 【Methods】 Based on the clinical REDCap system, the case-control research project of precocious puberty was created, the case report forms were designed, the user rights were set, and the data quality control rules were formulated. 【Results】 We established the electronic data capture and management platform for our research, which had 15 case report forms, to collect the data of the participants, including sociodemographic information, time for rest and activities, diet, exposure to environmental internal-secretion interfering-substances, physical examination and biochemical indicators. We conducted project management by setting up features such as user permissions and workgroups, and added data quality verification rules to control data quality. The data could be exported in various file formats for analysis and sharing. 【Conclusion】 The application of REDCap to establish the data capture and management platform of precocious puberty case-control study has promoted the efficient implementation of clinical research, which can be further popularized and applied to clinical researches in other fields.

Potential false-positive rate among the 'asymptomatic infected individuals’ in close contacts of COVID-19 patients / 中华流行病学杂志

Objective@#As the prevention and control of COVID-19continues to advance, the active nucleic acid test screening in the close contacts of the patients has been carrying out in many parts of China. However, the false-positive rate of positive results in the screening has not been reported up to now. But to clearify the false-positive rate during screening is important in COVID-19 control and prevention.@*Methods@#Point values and reasonable ranges of the indicators which impact the false-positive rate of positive results were estimated based on the information available to us at present. The false-positive rate of positive results in the active screening was deduced, and univariate and multivariate-probabilistic sensitivity analyses were performed to understand the robustness of the findings.@*Results@#When the infection rate of the close contacts and the sensitivity and specificity of reported results were taken as the point estimates, the positive predictive value of the active screening was only 19.67%, in contrast, the false-positive rate of positive results was 80.33%. The multivariate-probabilistic sensitivity analysis results supported the base-case findings, with a 75% probability for the false-positive rate of positive results over 47%.@*Conclusions@#In the close contacts of COVID-19 patients, nearly half or even more of the 'asymptomatic infected individuals’ reported in the active nucleic acid test screening might be false positives.

Interaction between pregnancy-induced hypertension and history of preterm birth on the risk of small for gestational age / 中华流行病学杂志

Objective@#To investigate the interaction of pregnancy-induced hypertension and history of preterm birth on the risk of small for gestational age.@*Methods@#Stratified multistage random sampling method was used to choose samples from 30 districts and counties of Shaanxi province. Information on childbearing-age women with their children between January 2010 and November 2013 was retrospectively collected through face-to-face questionnaire survey. The childbearing-aged women were in pregnancy or having had definite outcomes of pregnancy. Enumeration data were described by percentage, and measurement data were described by Mean±SD, and χ2 test was used to compare the rates. Unconditional logistic regression analysis was performed to estimate the interaction between pregnancy-induced hypertension and history of preterm birth on the risk of small for gestational age, and by using small for gestational age as dependent variables, pregnancy-induced hypertension and history of preterm birth as independent variables. Confounding factors were under control. Firstly, the association between pregnancy-induced hypertension and small for gestational age has been analyzed in primiparas, secondly, interaction of pregnancy-induced hypertension and history of preterm birth on the risk of small for gestational age has been analyzed in multiparas.@*Results@#A total of 25 751 women of childbearing age and their children were recruited. 60.55% (15 592/25 751) were primiparas, 39.45% (10 159/25 751) were multiparas, the rate of history of preterm birth was 1.89% (192/10 159) for multiparas. The incidence rates of pregnancy-induced hypertension and small for gestational age were 1.55% and 15.49% in pregnant woman (400/25 751) and their newborns (3 990/25 751). Unconditioned logistic regression analysis showed that compared with woman without pregnancy-induced hypertension, primiparas with pregnancy-induced hypertension had increased risk of small for gestational age (OR=1.43, 95%CI: 1.02-2.00, P=0.041). Regarding multiparas, the main effect of pregnancy-induced hypertension had a positive correlation with small for gestational age (OR=1.34, 95%CI: 0.91-1.96), but there was no statistical significance (P=0.138). The main effect of history of preterm birth was positively correlated with small for gestational age (OR=1.61, 95%CI: 1.13-2.31, P=0.009). The interaction term "pregnancy-induced hypertension×history of preterm birth" was positively associated with risk of small for gestational age (OR=5.93, 95%CI: 1.19-29.61, P=0.030).@*Conclusions@#Pregnancy-induced hypertension was associated with increased risk for small for gestational age in both primiparas and multiparas, and history of preterm birth further increased risk for small for gestational age in pregnant women with pregnancy-induced hypertension, indicating that there was multiplication interaction between pregnancy-induced hypertension and history of preterm birth.

Association between congenital heart disease and maternal disease in early pregnancy in women of childbearing age / 中华流行病学杂志

Objective@#To investigate the relationship between maternal disease in early pregnancy of women of childbearing age and congenital heart disease of neonates.@*Methods@#A cross-sectional design was used in this study and stratified multistage random sampling method was used. A questionnaire survey was conducted in the childbearing-aged women during 2010-2013 in Shaanxi province. Propensity score (PS) matched (1∶1) analysis was used to match participants with diseases to those without disease in early pregnancy. Through the control of the confounders step by step, a logistic regression model was established to evaluate the ORs of congenital heart disease according to the independent variable of maternal disease.@*Results@#A total of 28 680 pairs of mothers and infants were included in this study, the proportion of the women with disease in early pregnancy was 20.25% (5 807). After PS matching, 5 436 pairs were matched. After adjusting all confounding factors, the multivariable logistic regression analysis results showed that maternal disease (OR=1.86, 95%CI: 1.23-2.81), especially cold (OR=2.19, 95%CI: 1.46-3.28), gynecological disease (OR=4.74, 95%CI: 2.03-11.09) and diabetes (OR=14.00, 95%CI: 1.64-119.21), in early pregnancy were the risk factors for congenital heart disease of neonate.@*Conclusion@#In women of childbearing age, disease in early pregnancy, especially cold, gynecological disease and diabetes, can increase the risk of congenital heart disease in neonates.

A propensity score-matched study on relationship between maternal respiratory infection in early pregnancy and gestational age / 中华流行病学杂志

Objective To explore the association between maternal respiratory infection in early pregnancy and gestational age of single live birth.Methods A face to face questionnaire survey was conducted among child bearing aged women in 30 counties (district) of Shaanxi province selected through stratified multistage sampling.Propensity score (PS) matched (1 ∶ 1) analysis was used to match participants with respiratory infections to those without respiratory infections.A multilevel linear model was used to investigate the association between respiratory infections and gestational age.Through the control of the confounders step by step,three models were established in this study:model 1 for the variable of respiratory infections before PS matching,model 2 was adjusted for variables in model 1 plus some other individual differences of mother and baby,and model 3 for the variable of respiratory infections after PS matching.Results Of 28 848 child bearing aged women surveyed,3 676 (12.74％) had respiratory infections in early pregnancy.After PS matching,2 762 pairs were matched.Analysis with model 1 indicated that a decrease of 0.111 week (P＜0.001) in gestational age was associated with a respiratory infection during the first trimester.Analysis with model 2 and model 3 indicated that a decrease of 0.058 week (P=0.025) and a decrease of 0.076 week (P=0.036) were associated with respiratory infection during the fast trimester,respectively.Conclusion The respiratory infection during the first trimester was associated with the decrease of the gestational age of newborn.

A propensity score-matched study on relationship between maternal respiratory infection in early pregnancy and gestational age / 中华流行病学杂志

Objective To explore the association between maternal respiratory infection in early pregnancy and gestational age of single live birth.Methods A face to face questionnaire survey was conducted among child bearing aged women in 30 counties (district) of Shaanxi province selected through stratified multistage sampling.Propensity score (PS) matched (1 ∶ 1) analysis was used to match participants with respiratory infections to those without respiratory infections.A multilevel linear model was used to investigate the association between respiratory infections and gestational age.Through the control of the confounders step by step,three models were established in this study:model 1 for the variable of respiratory infections before PS matching,model 2 was adjusted for variables in model 1 plus some other individual differences of mother and baby,and model 3 for the variable of respiratory infections after PS matching.Results Of 28 848 child bearing aged women surveyed,3 676 (12.74％) had respiratory infections in early pregnancy.After PS matching,2 762 pairs were matched.Analysis with model 1 indicated that a decrease of 0.111 week (P＜0.001) in gestational age was associated with a respiratory infection during the first trimester.Analysis with model 2 and model 3 indicated that a decrease of 0.058 week (P=0.025) and a decrease of 0.076 week (P=0.036) were associated with respiratory infection during the fast trimester,respectively.Conclusion The respiratory infection during the first trimester was associated with the decrease of the gestational age of newborn.

Relationship between exposure to air pollutants during pre-pregnancy or early pregnancy and birth defects in Xi'an, 2013-2015: a case crossover study / 中华流行病学杂志

Objective To understand the levels of exposure to traffic-related air pollutants including nitrogen dioxide (NO2),PM10 and PM2.5,and the relationship between the exposure to air pollutants during pre-pregnancy or early pregnancy and birth defects.Methods Data on air pollution and birth defects from 2013 to 2015 was collected.A case-crossover design was employed to analyze the exposure-response relationship between traffic-related air pollutants and birth defects.Results A total of 4 235 pregnant women were studied.During the study period,the daily average concentrations of ambient NO2,PM10 and PM25 appeared as 60.83 μg/m3,104.94 μg/m3 and 103.88 μ.tg/m3,respectively,with the concentration of PM2.5 larger than the 2nd version of Standard National Ambient Air Quality Standard.In addition,there were strong correlations seen between each of the pollutants (P＜0.01).After adjustment for the influence of meteorological factors,it was found that the exposure to high level of NO2 and PM10 during pre-pregnancy or early pregnancy increased the risk on birth defects (P＜0.05).Conclusion Levels of exposure to adverse environmental factors during pre-pregnancy or early pregnancy could increase the risk of birth defects,suggesting that in these sensitive periods,women should try to avoid being exposed to high concentration of traffic-related air pollutants as NO2,PM10 etc.in order to reduce the risk of birth defects.

Association between illness and mental status in pregnant women and birth defects / 中华流行病学杂志

Objective To understand the prevalence of birth defects, related diseases and mental status of women during pregnancy in Shaanxi province and to analyse the major risk factors on birth defects and congenital heart disease. Possible association between maternal diseases or mental status and the risk of birth defects, was also explored. Methods A cross-sectional design was used in this study and stratified multistage random sampling method was used. The whole survey was from Jury 2013 to November 2013. Logistic regression method was used to analyze the association between maternal diseases, mental status during pregnancy and birth defects. Results The overall prevalence of birth defects was 195.04 per 10000 in Shaanxi. Among the 29121 mothers participating in this study, 51.1% developed illness and 6.8%"changed their mental status during pregnancy. After adjusting all the confounding factors, results showed that, histories of cold", fever, and intrahepatic cholestasis were (OR=1.33, 95%CI:1.10-1.61, OR=1.54, 95%CI:1.09-2.16, and OR=32.77, 95%CI:4.08-263.04) respectively, during pregnancy that related to birth defects. Self-reported unstable mental status (OR=1.60, 95%CI: 1.19-2.15) and family friction (OR=2.07, 95%CI: 1.12-3.79) were both related to the birth rates. Histories of cold and fever (OR=1.59, 95%CI:1.28-1.98;OR=1.43, 95%CI:1.48-4.00), during early pregnancy, unstable mental status during mid-pregnant period (OR=1.52, 95%CI:1.05-2.19), unstable mental status during late-pregnant period (OR=1.63, 95%CI:1.05-2.19) and family friction during late-pregnant period (OR=2.89, 95%CI:1.16-7.20) were found to be related to birth defects. Compared with those without history of cold, those with the history of cold during first (OR=1.24, 95%CI: 1.02-1.52) and second stages (OR=2.06, 95%CI: 1.30-3.26) of pregnancy were more likely to bear fetus with birth defects. Compared with those without these histories, those with histories of fever (OR=1.49, 95%CI:1.04-2.13), emotional problem (OR=1.71, 95%CI:1.19-2.45) and related diseases (OR=2.67, 95%CI: 1.32-5.39) during the first period of pregnancy were more likely to bear fetus with birth defects. Conclusion The incidence of birth defects in Shaanxi was high. Histories of cold, fever, unstable mental status and family friction during pregnancy, seemed to have increased the risks of bearing child with birth defects.

Relationship between air pollution exposure during pregnancy and birth weight of term singleton live-birth newborns / 中华流行病学杂志

Objective This study explored the association between air pollution exposure and birth weight by using the multilevel linear model,after controlling related meteorological factors and individual differences of both mothers and babies.Methods Women of childbearing age who were pregnant in Xi'an from 2010 to 2013,were selected as objects of this study.Multistage random sampling method was used to select 4 631 subjects followed by a self-designed questionnaire survey.Data related to quality of air and meteorology were gathered from routine monitoring system.Gestational age and date of birth,together with the average levels of air pollution were calculated for each trimester on each mother,and then the impact of air pollution on birth weight was assessed.A multilevel linear model was employed to investigate the association between the levels of exposure to air pollution by birth weight.Confounding factors were under control.We established three models in this study:Model 1 which involving the variable of air pollution exposure.Model 2 was adjusted for variables in Model 1 plus some other individual differences of both mother and baby.Model 3 was adjusted for variables in Model 2 plus meteorological factors.Results There were significant differences seen in birth weight within the subgroups of gender,gestational age,mother's reproductive age,maternal education,residential areas and family incomes (P＜0.01) of the infants.However,there was no difference found in Model 1 (P＞0.05).Data from Model 3 indicated that a decrease of 13.3 g (10.9 g in Model 2) and 6.6 g (5.9 g in Model 2) in birth weight that were associated with an increase of 10 μg/m3 in the average level of NO2 and PM10 during the second trimester;A decrease of 13.7 g (9.8 g in Model 2) in birth weight was associated with an increase of 10 μg/m3 in the average level of NO2 during the third trimester.Conclusion After controlling for meteorological factors,the levels of exposure to NO2 and PM10 during the second trimester and NO2 during the third trimester were negatively associated with birth weight.

Temperature that modifies the effect of air pollution on emergency room visits for circulatory and respiratory diseases in Beijing, China / 中华流行病学杂志

Objective To analyze the temperature modification effect on emergency room visits for circulatory and respiratory diseases caused by air pollution,in Beijing,Methods Data on both circulatory and respiratory diseases in 2010 and 2011 were collected,Both meteorological and air pollutants related data were obtained from the National Scientific Data Sharing Platform for Population and Health.By using the stratified time-series models,we analyzed the effects of air pollution on emergency room visits for circulatory and respiratory diseases under different temperature zones,from 2010 to 2011,in Beijing.Results Low temperature (daily average temperature ＜-4.9 ℃) seemed to have obviously enhanced the effect of air pollution index (API) on emergency room visits for circulatory diseases,Under 10 units of API,the relative risks and confidence interval appeared as 1.067 (1.054-1.080).However,high (daily average temperature between 24.4 ℃ and 28.5 ℃) and extra-high temperature (daily average temperature ＞28.5 ℃) could enhance the effect of API on emergency room visits for respiratory diseases,Under 10 units of API,the relative risks and confidence interval were 1.021 (1.015-1.028) and 1.006 (1.003-1.008),respectively.Conclusion Temperature seemed to have modified the association between air pollution and both circulatory and respiratory diseases.

Study on relationship between mother's animal sourced food intake during pregnancy and neonate birth weight / 中华流行病学杂志

Objective To explore the effect of maternal animal sourced food intake during pregnancy on neonate birth weight and provide scientific basis for guiding the reasonable diet intake in pregnant women and increasing neonate birth weight.Methods Data were derived from a cross-sectional project of "the prevalence and risk factors of birth defects in Shaanxi province",which were conducted in 30 counties in Shaanxi province from July to November in 2013.A stratified multistage random sampling method was used to select women who were pregnant between January 2010 and December 2013 for a random semi-quantitative food frequency questionnaire survey to collect the data on the frequency and amount of food consumption on animal protein sources and the data of newborns.Children aged 0-1 years and their mothers were selected as the study subjects.The generalized linear model was used to analyze the relationship between the neonate birth weight and maternal animal sourced food intake during pregnancy,and by using neonate birth weight as dependent variable,food intake frequency as independent variable,three adjustment models were established for stratified analysis.Results Totally 11 459 participants were involved in this study.The average birth weight of newborn was (3 279.9 ± 454.6) g,the average weekly intake of animal sourced foods was 4.00 times for egg,1.50 times for meat,3.00 times for dairy foods,0.50 times for fish and 5.00 times for overall animal sourced foods in pregnant women.Without stratification,three models shown that meat and overall animal sourced food intake had effects on neonate birth weight.After adjustment for gestational weeks,maternal age,social and demographic factors and others,meat intake increased by 1 time a week,the increase of neonate birth weight was about 5.26 (95％ CI:1.32-9.20) g,and the overall animal food increased by 1 times a week,the average neonate birth weight increased by 3.24 (95％ CI:1.09-5.39) g.Stratified analysis showed that meat and overall animal sourced food always had more influences on baby girls and those living in rural area.In the region classification,the overall animal sourced food intake had more influences on women living in northern area and Guanzhong area of Shaanxi,and meat intake had greater influence on women living in southern Shaanxi.And the influences were positive,the more animal sourced foods were taken,the greater the birth weight increased.Conclusion Animal sourced food intake during pregnancy would benefit the increase of neonate birth weight.It suggests that pregnant women should pay more attention to the intake of animal sourced food.

Spatial distribution and clustering in birth defects from 2010 to 2013 in Shaanxi Province / 中南大学学报(医学版)

Objective:To explore the spatial distribution and clustering in birth defects from 2010 to 2013 in Shaanxi Province.Methods:Spatial distribution was used to describe the birth defects,while ordinary Kriging method was used to predict the status of birth defects in Shaanxi province.The spatial characteristics for the birth defects at the county/district level were analyzed by spatial autocorrelation.Results:The overall incidence of birth defects was 219.196/10 000;Birth defect did not appear to be a random distribution but show a significant spatial aggregation.Spatial interpolation predicted the geographic distribution for occurrence of birth defects in Shaanxi Province.Local autocorrelation analysis showed nine hot spot areas for birth defects,such as Qian County,Liquan County,Yongshou County,Bin County,Fufeng County,Jingyang County,Chunhua County,Wugong County and Xingping City,and seven cold spot areas including Jia County,Yuyang District,Mizhi County,Suide County,Wubu County,Qingjian County and Zizhou District.Conclusion:There are spatial clustering in birth defects from 2010 to 2013 in Shaanxi Province.Spatial interpolation and spatial autocorrelation can be used to predict the spatial features of birthdefects in the whole province and provide evidence for the further intervention.

Ecological research on time series changes in air pollutants and birth defects in Xi'an and their correlation / 西安交通大学学报(医学版)

Objective To analyze the trend of birth defects and air pollution in Xi'an and discuss the correlation between air pollution exposure and birth defects.Methods Time series multiplication model was used to decompose the time series of birth defects and concentration of air pollutants to describe their long-term trend and seasonal variations.The rank correlation and cross-correlation between birth defects and air pollutants were analyzed by ecological approach.Results During 2010-2015,the results of air pollution analysis in Xi'an showed that the overall trend of NO2 increased in 2013 and then fluctuated at a high level.Generally,SO2 showed a trend of slow decline,but there were two peaks in 2012 and 2013.The overall trend of PM10 had two small peaks in 2013 and 2014,and during the rest of the time the change was stable.The overall trend of PM2.5 showed a slow decline,but after 2015 it showed a slight increase.Analysis of the birth defects during 2010-2015 in Xi'an showed that the long-term trend of total birth defects and congenital heart disease increased in 2010-2014,but then decreased rapidly.The long-term trend of cleft lip and palate and neural tube defects fluctuated at a low level.Analysis of the correlation between air pollutants and birth defects showed that total birth defects and congenital heart disease were positively correlated with NO2 at 3 months before pregnancy and early 3 months of pregnancy.Congenital heart disease 3 months before pregnancy had a positive correlation with PM10.Conclusion Birth defects and air pollution in Xi'an have trend variations and seasonal regularity.There is a positive correlation of women's exposure to NO2 3 months before pregnancy and the first 3 months of pregnancy with the incidence of congenital heart disease.

Spatial distribution characteristics of birth defects and air pollution in Xi'an between 2010 and 2015 / 西安交通大学学报(医学版)

Objective To analyze the spatial distribution characteristics of birth defects and air pollution in Xi'an and the correlation between air pollution exposure and birth defects.Methods In this study,we calculated the mean and median concentration of air pollutants in Xi'an between 2010 and 2015 to describe their concentration trends.Then we analyzed quartile range to describe their discrete trend.The spatial distribution of air pollution in the whole study area was calculated by inverse distance weighted spatial interpolation method to describe its overall occurrence level.The global trend was analyzed to describe the main body change pattern in the birth defect space.The total number of birth defects in the districts and counties of Xi'an between 2010 and 2015 was calculated and the incidence of birth defects was calculated according to the monitoring data of live births.Correlation between birth defects and air pollution was analyzed by rank correlation analysis.Results The spatial distribution of air pollutants in Xi'an between 2010 and 2015 was as follows:the concentration of SO2 was relatively high in Lianhu District,Yanta District,Baqiao District,Beilin District,and Xincheng District.The concentration of NO2 was relatively high in Yanta District,Baqiao District,Lianhu District,Beilin District,and Xincheng District.The concentration of PM10 was relatively high in Baqiao District,Yanta District,Xincheng District,Weiyang District,and Yanliang District.In Baqiao District,Xincheng District,Lianhu District,Weiyang District,and Gaoling District,the concentration of PM2.5 was relatively high.The total number of birth defects was 6 858 cases in Xi'an between 2010 and 2015,and the total number of perinatal births was 752 142 cases,with the incidence of 91.18 (1/10 000).The spatial distribution of birth defects from the west to the east direction and from south to north direction was generally characterized of inverted U type.The birth defects were positively correlated with NO2 concentration.Conclusion There are obvious regional differences in air pollution and birth defects in Xi'an.Birth defects may be related to NO2.

Time-series analysis of air pollution and birth defects during 2010 to 2015 in Xi'an / 西安交通大学学报(医学版)

Objective To study the effects of air pollution including sulphur dioxide (SO2),nitrogen dioxide (NO2) and PM10 in Xi'an on birth defects.Methods We collected the birth defects data from Xi'an Maternal and Child Health Hospital,meteorological data from Xi'an Bureau of Meteorology,and the air pollution data from Xi'an Environment Monitoring Station from 2010 to 2015.Generalized additive model (GAM) was used to explore the relationship between air pollution and birth defects after adjusting the effects of long-term and seasonal trend,temperature,and relative humidity.Results The monthly average birth defects were 89 cases;the monthly average concentration of SO2,NO2 and PM10 was 34.05 μg/m3,45.13 μg/m3,and 96.77 μg/m3,respectively.In the GAM,the monthly average temperature was 13.57 ℃ and the relative humidity was 63.20％.The three kinds of air pollutants all had a certain lag effect in 10 months,which reached the maximum.With an increase of concentration by 10 μg/m3 in three air pollutants,the relative risks and confidence interval of SO2,NO2,and PM10 were 1.060 (1.023-1.097),1.033 (1.014-1.052) and 1.018 (1.007-1.029),with significant differences (P＜0.05).Conclusion Exposure to SO2,NO2,and PM10 may be associated with the risk of birth defects.

The epidemiological characteristics of perinatal birth defects in Xi'an from 2010 to 2015 / 西安交通大学学报(医学版)

Objective To investigate the dynamic epidemiological characteristics of perinatal birth defects in Xi'an so as to provide scientific evidence for the priority of future birth defect prevention.Methods We made a statistical description of the data of perinatal birth defects from 2010 to 2015 reported by all the maternity hospitals in Xi'an.Results The incidence of birth defects in Xi'an from 2010 to 2015 was 89.62/104 (87.60/104,91.74/ 104) and had an annual ascending tendency (x2-157.13,P＜0.01).The top five main birth defects in a descending order were congenital heart disease (26.53/104),polydactyly (13.10/104),total cleft lip (11.42/104),neural tube defects (6.06 /104),and congenital hydrocephalus (5.08/104),accounting for 69.39％ of the total number of birth defects.And the incidence of congenital heart diseases showed a year-by-year ascending trend (x2=837.65,P＜ 0.01).The incidence of birth defects was higher in urban areas than in rural areas (OR 1.108,95％ CI:1.056-1.162).The birth defects were more frequently seen in males than in females (OB=1.151,95％ CI:1.097-1.208).Mother's age ＜20 (OR=1.764,95％ CI..1.532-2.032) and mother'sage≥35 (OR=1.283,95％ CI:1.179-1.395) also were risk factors for birth defects.Up to 72.54％ of the defects were live births.There were 52.83％ cases diagnosed by ultrasound and 46.24％ ones by clinical examination.The prenatal diagnosis rate was 33.20％.Conclusion The incidence of perinatal birth defects in Xi'an from 2010 to 2015 showed an annual ascending trend.We should improve the prenatal diagnosis level of all monitored hospitals in order to reduce incidence of birth defects and increase the quality of population.

Application of multiple seasonal ARIMA model in predication of birth defect incidence in Xi'an area / 西安交通大学学报(医学版)

Objective To predict the incidence of birth defects in Xi'an using the auto-regressive integrated moving average product seasonal model.Methods In Xi'an,the trend of the incidence of birth defects was analyzed and tested from October 2009 to August 2015.Using the data from September to December 2015,the actual birth defects were compared with the model fitting data to evaluate the predictive performance of the model.Multiple seasonal ARIMA model was then fitted under time series to predict the incidence of birth defects in 2016.Results Seasonal effect was seen in the incidence of birth defects in Xi'an.A multiple seasonal ARIMA(0,0,1) (0,1,1)12 was established.The mean of absolute error and the relative error were 9.5 and 0.084,respectively,when compared to the simulated number of patients from September to December in 2015,suggesting that ARIMA (0,0,1) (0,1,1)12 has a better predictive ability.Results under the prediction of multiple seasonal ARIMA model showed that the number of patients in 2016 was similar to that of 2015 in Xi'an,with a slight increase and a decrease in the peak value.Conclusion Multiple seasonal ARIMA(0,0,1)(0,1,1)12 model could be used to successfully predict the incidence of birth defects in Xi'an.

Relationship between exposure to air pollutants during pre-pregnancy or early pregnancy and birth defects in Xi'an, 2013-2015: a case crossover study / 中华流行病学杂志

Objective To understand the levels of exposure to traffic-related air pollutants including nitrogen dioxide (NO2),PM10 and PM2.5,and the relationship between the exposure to air pollutants during pre-pregnancy or early pregnancy and birth defects.Methods Data on air pollution and birth defects from 2013 to 2015 was collected.A case-crossover design was employed to analyze the exposure-response relationship between traffic-related air pollutants and birth defects.Results A total of 4 235 pregnant women were studied.During the study period,the daily average concentrations of ambient NO2,PM10 and PM25 appeared as 60.83 μg/m3,104.94 μg/m3 and 103.88 μ.tg/m3,respectively,with the concentration of PM2.5 larger than the 2nd version of Standard National Ambient Air Quality Standard.In addition,there were strong correlations seen between each of the pollutants (P＜0.01).After adjustment for the influence of meteorological factors,it was found that the exposure to high level of NO2 and PM10 during pre-pregnancy or early pregnancy increased the risk on birth defects (P＜0.05).Conclusion Levels of exposure to adverse environmental factors during pre-pregnancy or early pregnancy could increase the risk of birth defects,suggesting that in these sensitive periods,women should try to avoid being exposed to high concentration of traffic-related air pollutants as NO2,PM10 etc.in order to reduce the risk of birth defects.

Association between illness and mental status in pregnant women and birth defects / 中华流行病学杂志

Objective To understand the prevalence of birth defects, related diseases and mental status of women during pregnancy in Shaanxi province and to analyse the major risk factors on birth defects and congenital heart disease. Possible association between maternal diseases or mental status and the risk of birth defects, was also explored. Methods A cross-sectional design was used in this study and stratified multistage random sampling method was used. The whole survey was from Jury 2013 to November 2013. Logistic regression method was used to analyze the association between maternal diseases, mental status during pregnancy and birth defects. Results The overall prevalence of birth defects was 195.04 per 10000 in Shaanxi. Among the 29121 mothers participating in this study, 51.1% developed illness and 6.8%"changed their mental status during pregnancy. After adjusting all the confounding factors, results showed that, histories of cold", fever, and intrahepatic cholestasis were (OR=1.33, 95%CI:1.10-1.61, OR=1.54, 95%CI:1.09-2.16, and OR=32.77, 95%CI:4.08-263.04) respectively, during pregnancy that related to birth defects. Self-reported unstable mental status (OR=1.60, 95%CI: 1.19-2.15) and family friction (OR=2.07, 95%CI: 1.12-3.79) were both related to the birth rates. Histories of cold and fever (OR=1.59, 95%CI:1.28-1.98;OR=1.43, 95%CI:1.48-4.00), during early pregnancy, unstable mental status during mid-pregnant period (OR=1.52, 95%CI:1.05-2.19), unstable mental status during late-pregnant period (OR=1.63, 95%CI:1.05-2.19) and family friction during late-pregnant period (OR=2.89, 95%CI:1.16-7.20) were found to be related to birth defects. Compared with those without history of cold, those with the history of cold during first (OR=1.24, 95%CI: 1.02-1.52) and second stages (OR=2.06, 95%CI: 1.30-3.26) of pregnancy were more likely to bear fetus with birth defects. Compared with those without these histories, those with histories of fever (OR=1.49, 95%CI:1.04-2.13), emotional problem (OR=1.71, 95%CI:1.19-2.45) and related diseases (OR=2.67, 95%CI: 1.32-5.39) during the first period of pregnancy were more likely to bear fetus with birth defects. Conclusion The incidence of birth defects in Shaanxi was high. Histories of cold, fever, unstable mental status and family friction during pregnancy, seemed to have increased the risks of bearing child with birth defects.