Evaluation of Four Candidate VNTR Loci for Genotyping 225 Chinese Clinical Mycobacterium Tuberculosis Complex Strains

Objective To evaluate four candidate variable number tandem repeat （VNTR） loci for genotyping Mycobacterium tuberculosis complex strains. Methods Genomic sequences for two M. tuberculosis strains （CCDC5079 and CCDC5180） were generated, and using published sequence data, four candidate VNTR loci were identified. The VNTRs were used to genotype 225 Chinese clinical M. tuberculosis complex strains. The discriminatory power of the VNTRs was evaluated using BioNumerics 5.0 software. Results The Hunter-Gaston Index （HGI） for BJ1, BJ2, BJ3, and BJ4 loci was 0.634, 0.917, 0.697, and 0.910, respectively. Combining all four loci gave an HGI value of 0.995, thus confirming that the genotyping had good discriminatory power. The HGI values for BJ1, BJ2, BJ3, and BJ4, obtained from Beijing family strain genotyping, were 0.447, 0.878, 0.315, and 0.850, respectively. Combining all four loci produced an HGI value of 0.988 for genotyping the Beijing family strains. We observed unique patterns for M. boris and M. africanum strains from the four loci. Conclusion We have shown that the four VNTR loci can be successfully used for genotyping M. tuberculosis complex strains. Notably, these new loci may provide additional information about Chinese M. tuberculosis isolates than that currently afforded by established VNTR loci typing.

How hypertensive patients in the rural areas use home blood pressure monitoring and its relationship with medication adherence: A primary care survey in China

Despite an increasing popularity of home blood pressure monitoring (HBPM) over the last few decades, little is known about HBPM use among hypertensive patients in the rural areas. A cross-sectional survey including 318 hypertensive patients was conducted in a rural community in Beijing, China, in 2012. Participants were mainly recruited from a community health clinic and completed the questionnaires assessing HBPM usage. Binary logistic regression models were used for the analysis of medication adherence with age, gender, level of education marital status, perceived health status, duration of hypertension, HBPM use, and frequency of performing BP measurement. Among the total population, 78 (24.5%) reported currently use of HBPM. Only 5.1% of the HBPM users cited doctor’s advice as the reason for using HBPM. Analysis of the risk factors of poor medication adherence by multivariable modeling indicated significant associations between the duration of hypertension (adjusted OR, 3.31;95% CI, 1.91-5.72;P 01), frequency of performing BP measurements (adjusted OR, 2.33;95% CI, 1.42-3.83;

Diabetes awareness, treatment, control rates and associated risk factors among Beijing residents in 2011:A cross-sectional survey

Objective: To examine the awareness, treatment and control rates of diabetes and identify their associated risk factors among Beijing residents. Methods: A cross-sectional survey was conducted in 2011, using a stratified multistage cluster random sampling method to select a representative sample of 20,242 residents in Beijing aged 18e79 years. Diabetes was defined as fasting blood glucose (FBG)≥7.0 mmol/L and/or history of diabetes and/or using insulin or hypoglycemic agents. All estimates of awareness, treatment and control rates were weighted by the 2010 Beijing Population Census data and the sampling scheme. Multivariate Logistic regression was used to identify factors associated with awareness, treatment and control rates. Results: A total of 2061 (10.3%) participants were diagnosed as diabetes. The overall awareness, treatment and control rate among patients were 60.9%, 51.3% and 22.4%, respectively, while overall control rate among treated patients was 33.8%. These rates differed across subgroups. Women were more likely to be aware of diabetes status, receive treatment and have better glucose controlled than men (69.5%vs. 54.7%for awareness, 61.0%vs. 44.3%for treatment, and 27.6%vs. 18.6%for control, respectively). In addition, only 22.2%of treated patients had both FBG and hemoglobin A1c (HbA1c) controlled well. Multivariate Logistic regression suggested that old age, women, higher education and family history of diabetes were asso-ciated with higher awareness, treatment and control rates (All P<0.05). Treated individuals living in rural (OR ? 0.67(95%CI: 0.47e0.96)) or with dyslipidemia (OR ? 0.63 (95%CI: 0.44e0.91)) had a lower diabetic control rate. Conclusions: Awareness, treatment and control rates of diabetes in Beijing were still low. A comprehensive intervention strategy on diabetes management and control is warranted.

Clustering of Risk Behaviors and their Social Determinants among Primary School Learners in Beijing, China：A Cross-sectional Study

Background：Studies in developed countries reveal that poor lifestyle choices triggering diseases typically cluster among children.However,there is insufficient evidence on the clustering of risk behaviors among children in developing countries.This study aimed to determine the clustering of risk behaviors and their social determinants among 4th-and 5th-grade learners in Beijing,China.Methods：The sample comprised of 967 learners from six primary schools enrolled migrant and resident learners by two-stage stratified cluster sampling.Prevalence denoted the risk behaviors and their clustering.A log-linear model was used to explore the clustering patterns.Ordinal logistic regression determined the influence of demographic characteristics,school environment,and family context on behavioral clustering.Results：The prevalence of none,one,two,and three or more risk factors was 61.2%,20.0%,10.8%,and 8.1% for infectious diseases and 46.0%,30.6%,15.4%,and 8.0% for chronic diseases,respectively.Some behaviors appeared dependent and were more likely to be observed together.The three most influential factors for infectious diseases were school type （odds ratio [OR] =4.47,95% confidence interval [CI] 3.00-6.66）,school located in an inner suburb （OR =0.27,95% CI 0.18-0.38）,and gender （OR =0.56,95% CI 0.42-0.74）.Regarding risk behaviors for chronic diseases,clustering was not associated with household registration status and number of appliances,but was significantly associated with school type （OR =5.36,95% CI 3.72-7.73）,school located in an inner suburb （OR =0.59,95% CI 0.43-0.81）,and gender （OR =0.61,95% CI 0.47-0.78）.School environment variables were the most significant contributor to the number of risk behaviors.Conclusions：The characteristics of schools enrolling migrants and residents influenced the number of risk behaviors.Therefore,improved school conditions and integrated behavioral interventions are particularly recommended for health promotion.

Prevalence of active and passive tobacco smoking among Beijing residents in 2011

Objectives: This study was aimed to investigate the prevalence of active and passive tobacco smoking among Beijing residents in 2011. Methods: A cross-sectional survey was conducted, using a stratified multistage cluster random sampling method to select a representative sample of 20,242, among Beijing residents aged 18-79 years. Active and passive tobacco smoking information was collected by a standardized and validated questionnaire in a face-to-face interview. All estimates of prevalence and numbers were weighted by the 2010 Beijing Population Census data and the sampling scheme. Results: Among Beijing residents aged 18-79 years, the overall prevalence of ever smokers and current smokers were 33.13%and 30.18%, respectively. The prevalence in males was much higher than that in females (60.75%vs. 3.75%for ever smokers, and 55.53% vs. 3.21% for current smokers, respectively). For overall current smokers, 14.12 cigarettes were consumed per day. However, only 8.91%of ever smokers quitted smoking at the time of the survey, and 2.44%of ever smokers quitted smoking in recent two years. Furthermore, 44.74%of overall nonsmokers and former smokers, with 47.03%of males and 43.63%of females, reported exposure to secondhand smoke for at least 15 minutes per day and at least one day per week. Conclusions: Tobacco smoking prevalence is still extremely high in Beijing. Nonsmokers do still suffer from secondhand smoke critically. Further urgent efforts for tobacco control are warranted in Beijing.

HIV incidence among men who have sex with men using geosocial networking smartphone application in Beijing, China: an open cohort study

Background:Sexual transmission among men who have sex with men(MSM)is the dominant route of HIV transmission in China.Extensive use of geosocial networking(GSN)smartphone application(app)has dramatically changed the pattern of sexual behaviors and HIV risk among MSM;but data on HIV incidence and the changing risk behaviors of GSN app-using MSM are limited.We aims to assess the HIV incidence and its correlates among gay GSN app-using MSM in China.Methods:We constructed an open cohort which was initiated and maintained using a GSN app to assess the HIV incidence among app-using MSM,recruited from June 2017 to December 2018.MSM completed an online questionnaire on their sociodemographic characteristics,sexual behaviors,recreational drug use and sexually transmitted infections status.Then each man had an HIV test,and those tested negatives were enrolled into the cohort.Participants completed follow-ups with additional HIV tests though the app during the study period,and were censored at HIV seroconversion or study end date.HIV incidence was calculated by dividing the sum of observed HIV seroconversions by the observed person-time.Univariate(Chi-square test and Fisher's exact test)and multivariate(proportional hazards regression)analyses were used to examine correlates of HIV incidence.Results:A total of 6957 HIV negative MSM were enrolled in the open cohort,37 seroconversions occurred among 1937 men contributing 1065 observed person-years:HIV incidence was 3.47 per 100 person-years[95%confidence interval(Cl):2.37-4.57].More than five sexual partners[hazard ratio(HR)=2.65,95%Cl:1.04-6.67],and sex with HIV positive partners(HR=3.82,95%Cl:1.16-12.64)in the preceding six months were positively associated with HIV seroconversion.Consistent condom use for anal sex(HR=0.27,95%Cl:0.07-0.96),and reporting insertive anal sex only(HR=0.23,95%Cl:0.08-0.62)in the preceding six months were protective factors for HIV seroconversion.Conclusions:Tailored interventions targeting app-using MSM are urgently needed given their high risk of HIV.As a new tool for accessing MSM at higher HIV risk,GSN smartphone app could play an important role in HIV research among MSM.