Objective To explore the relationship of four kinds of lifestyle factors,namely,prenatal passive smoking,hair dyeing or perming,exposure to noise,living in a house renovated in the past one year,with congenital heart disease.Methods A hospital-based case-control study was conducted.Totally 270 mothers in the case group and 1633 mothers in the control group were interviewed through a face-to-face questionnaire survey.A generalized linear model was employed to investigate the association between congenital heart disease and prenatal lifestyle factors.Results Both in Model 1 and Model 2,prenatal hair dyeing or perming had no association with congenital heart disease.On the other hand,prenatal passive smoking,exposure to noise and living in a house renovated in the past one year all increased the risk of congenital heart disease.After adjustment for all confounders,the OR values were 1.771 (95％ CI:1.079-2.909),2.079 (95％ CI:1.310-3.298),and 2.494 (95％ CI:1.511-4.116),respectively.Conclusion Prenatal passive smoking,exposure to noise and living in a house renovated in the past one year are the risk factors for congenital heart disease.It is very important to avoid such factors during pre-pregnancy and pregnancy.

ObjectiveObjective To systematically evaluate the efficacy and safety of antiviral therapy in patients with chronic hepatitis B (CHB) in the immune-tolerant phase. MethodsPubMed, Embase, Cochrane Library, CNKI, and Wanfang Data were searched for clinical trials of antiviral therapy for CHB patients in the immune-tolerant phase published up to September 2020. Related data were extracted after quality assessment for systematic review. HBV DNA clearance rate was the primary outcome. ResultsA total of 9 studies involving 821 patients were included. Eight studies reported HBV DNA clearance rate in the treatment group, among which 6 studies had an HBV DNA clearance rate of ＞60%, which was significantly higher than that in the untreated patients (0%-29.1%), and the combination therapy group had a better clearance rate than the monotherapy group. However, virologic recurrence was more common in the long term. Eight studies reported HBeAg seroconversion, and only 2 studies of the treatment of children with interferon-α (IFN-α) reported a seroconversion rate of ＞20% in the treatment group, which was higher than that in the untreated group. HBsAg clearance was observed in 2 studies of IFN-α treatment, while HBsAg seroconversion was not observed. One study reported the risk of liver cirrhosis and hepatocellular carcinoma (HCC) and showed that antiviral therapy could reduce the risk of liver cirrhosis and HCC in patients. The incidence rate of adverse events ranged from 4.1%-13.0% in the treatment with nucleos(t)ide analogues and reached 100% in the treatment with IFN-α, and serious adverse events were rare. ConclusionThe majority of CHB patients in the immune-tolerant phase show satisfactory virologic response after antiviral therapy, but they tend to experience recurrence after drug withdrawal and have a low seroconversion rate. Antiviral therapy has good safety. Current evidence suggests that such patients can be dynamically observed if there is no clear evidence for disease progression.

Objective To explore the association between exposure to ambient air pollution during pregnancy and congenital heart disease so as to provide evidence for primary prevention of congenital heart disease.Methods Epidemiologic studies on ambient air pollution and congenital heart diseases were reviewed.Summary risk estimates were calculated at high versus low exposure levels and risk per-unit-increase in continuous pollutant concentration.Meta-analysis was conducted with Stata 12.0 software.Results A total of 20 articles in English were qualified for inclusion.Results from Meta-analysis showed that CO exposures were related to the increase on the risk of tetralogy of fallot (high versus low exposure level OR=1.22,95％CI:1.03-1.44),while the exposures to NO2 were related to the increase on risk of coarctation of aorta (per 10 mm3/m3 OR=1.01,95％CI:1.01-1.20).Exposures to O3 were related to the increase on risk of atrial septal defect (per 10 mm3/m3 OR=1.14,95％CI:1.03-1.26),and PM10 exposures were related to the increase on risk of atrial septal defect (per 10 μg/m3 OR=1.10,95％CI:1.03-1.19).In addition,there were inverse associations between CO and atrial septal defect and between PM10 and ventricular septal defect.Conclusion Exposures to CO,NO2,O3,PM10 during pregnancy seemed to be associated with congenital heart diseases.

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.

Objective To explore the effect of exposure to noise of 3.0T magnetic resonance imaging(MRI)on children's cochlear function.Methods We prospectively recruited 72 children who underwent cranial MRI examination at our hospital from May to November 2018;3M earplugs and sponge mats were used for hearing protection during MRI scanning.Noise level(dBA)of each MRI sequence was detected with a nonmagnetic microphone and a sound level meter.Distortion product otoacoustic emissions(DPOAE)test at 2-7 kHz was performed 24 hours before and 30 minutes after the MRI examination.Paired t-test or Wilcoxon signed-rank test was used to analyze differences in DPOAE amplitude before and after the MRI examination.Results The average noise level of MRI measured in the study was(107.7±3.92)dBA.Compared with that before the MRI examination,the DPOAE amplitude(dB)changed little after the MRI examination;the range of amplitude differences in each age group was as follows:left ear(-0.24-1.10)and right ear(-0.24-0.74)in the 0-1 year-old group;left ear(-0.07-0.59)and right ear(-0.57-0.75)in the 2-5 year-old group;left ear(-0.36-0.44)and right ear(-0.30-0.57)in the 6-12 year-old group.No statistically significant difference was found(correction P＞0.05).Conclusion No potential impact of 3.0T MRI noise on children's cochlear function was observed under routine hearing protection.

【Objective】 To explore the dynamic change of depression in diabetic patients so as to provide evidence for early detection and warning of psychological problems in diabetic patients. 【Methods】 Based on the data from the China Health and Retirement Longitudinal Study （CHARLS）， the propensity score matching method was used to eliminate confounding factors in the study. The linear growth model， the nonlinear quadratic growth model， and the growth model without defined curve type were fitted respectively. According to the fitting indices of the models， the optimal solution of the growth function was determined to explore the changes of depression development in the diabetic patients. 【Results】 A total of 5 711 cases （5 380 cases in the non-diabetic group and 331 cases in the diabetic group） were included in the study. After propensity score matching， 1 621 cases （1 291 cases in the non-diabetic group and 330 cases in the diabetic group） were included and all confounding factors were balanced between the two groups. By fitting three growth curve models with latent variables， the results showed that the model without defined curve type was better than the other two models. The mean depression score for initial status in the non-diabetic and diabetic groups was 9.640 and 10.097， respectively， with significant inter-individual differences. During the follow-up period， the depression status of both groups showed a trend of decrease first and then increase， but the depression score was always lower in the non-diabetic group than in the diabetic group. At the same time， there was no individual difference in the rate of change between the two groups， and there was no statistical difference between the initial depression score and the subsequent slope of change. 【Conclusion】 Exploring the change track of depression status over time in diabetic patients， understanding the individual psychological change trend and further explaining the differences between individuals are of great significance for intervention on psychological status at different stages.

【Objective】 To compare the performance of five commonly used variable selection methods in high-dimensional biomedical data variable screening so as to explore the effects of sample size and association among candidate variables on screening results and provide evidence for the development of variable selection strategy in high-dimensional biomedical data analysis. 【Methods】 Variable selection algorithms were implemented based on R-programming language. Monte Carlo method was used to simulate high-dimensional biomedical data under different conditions to evaluate and compare the performance of different variable selection methods. Variable selection performance was evaluated based on the true positive rate and true negative rate in screening. 【Results】 For specified high-dimensional data, the variable selection performance was improved for all the methods when sample size was increased, and the association between candidate variables did affect variable screening results. Simulation results indicated that the elastic network algorithm yielded the best screening performance, LASSO algorithm took the second place, and ridge algorithm did not work at all. 【Conclusion】 Elastic network algorithm is an ideal variable screening method for high-dimensional data variable screening.

【Objective】 To compare the ability of body mass index （BMI）， body fat percentage （BFP）， waist circumference （WC）， waist-to-height ratio （WHtR）， visceral fat index （VFI） and the combinations of two kinds of obesity indices to predict the risk of hypertension. 【Methods】 Data collected in the baseline survey of “Gansu Province’s Urban and Rural Natural Population Cohort Establishment and Tumor Follow-up Study” were analyzed. Area under the curve （AUC） of ROC curve with covariates was used to analyze and compare the effects of individual obesity evaluation index and the combination of two kinds of obesity indices in predicting the risk of hypertension. 【Results】 Analyses of data of 20，079 adults showed that the AUC of BMI， WC， WHtR， BFP and VFI was 0.636， 0.604， 0.615， 0.614 and 0.619， respectively. AUC of the combination of BMI and WC （0.643） was higher than that of BMI （0.636）； however， the change rate of AUC was only 1.09%. AUC of the combinations of WC， WHtR and VFI， the three central obesity evaluation indices， and BFP， a general obesity evaluation index， were lower than that of BMI. The optimal cutoff value for BMI was 24.2 kg/m². 【Conclusion】 The effect of BMI in predicting the risk of hypertension is better than that of BFP， WC， WHtR and VFI. The effects of the combinations of the two kinds of obesity evaluation indices are not better than that of BMI. To prevent and control hypertension， adults should keep their BMI under overweight.

【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.

【Objective】 To evaluate the dietary quality with the dietary balance index (DBI_16) and the association between dietary quality and bone mass among middle-aged and elderly people in Gansu Province so as to provide evidence for improving dietary quality and bone health status of Gansu population. 【Methods】 Based on the information of the type and quantity of food intake and the bone mass of middle-aged and elderly people aged 35 years and above collected by the Gansu Project in the Regional Ethnic Cohort Study in Northwest China, DBI_16 was used to evaluate the intake level of cereals, vegetables, fruits, milk, beans, fish and shrimp, eggs and other foods, and the degree of inadequate, excessive and unbalanced dietary intake of the participants. Multiple linear regression was used to evaluate the associations of three component indexes of DBI_16, high bound score (DBI_HBS), low bound score (DBI_LBS), diet quality distance (DBI_DQD), and seven single indexes of DBI_16 with bone mass. 【Results】 Analyses of the dietary and bone mass data of 11,840 participants showed that 44.8% of participants consumed excessive amounts of cereals compared to the dietary recommendation. 96.3%, 90.6%, 90.1%, 71.9%, 95.1% and 60.3% of participants’ intake of vegetables, fruits, milk, soybeans, fish and shrimp, and eggs, respectively, were inadequate. 47.7% participants consumed less than 10 types of food. 2.3% participants’ DBI_LBS levels were appropriate. 54.7% participants’ DBI_HBS levels were appropriate. Only 1.2% participants’ DBI_DQD reached a balanced level. The bone mass level in the study population was (2.5±0.6) kg [(2.8±0.5) kg for men and (2.3±0.5) kg for women]. After adjusting for sociodemographic characteristics, lifestyle, total dietary energy intake and body mass index, DBI_LBS and DBI_DQD were negatively associated with bone mass [β and 95% CI was -0.002 01 (-0.003 62--0.000 40) and -0.001 76 (-0.003 09--0.000 43), respectively]. 【Conclusion】 Dietary intake imbalance is common among middle-aged and elderly people in Gansu Province, and the more severe the dietary intake imbalance, the lower the bone mass level.