Predicting risk of preterm birth in singleton pregnancies using machine learning algorithms.

We aimed to develop, train, and validate machine learning models for predicting preterm birth (<37 weeks' gestation) in singleton pregnancies at different gestational intervals. Models were developed based on complete data from 22,603 singleton pregnancies from a prospective population-based cohort study that was conducted in 51 midwifery clinics and hospitals in Wenzhou City of China between 2014 and 2016. We applied Catboost, Random Forest, Stacked Model, Deep Neural Networks (DNN), and Support Vector Machine (SVM) algorithms, as well as logistic regression, to conduct feature selection and predictive modeling. Feature selection was implemented based on permutation-based feature importance lists derived from the machine learning models including all features, using a balanced training data set. To develop prediction models, the top 10%, 25%, and 50% most important predictive features were selected. Prediction models were developed with the training data set with 5-fold cross-validation for internal validation. Model performance was assessed using area under the receiver operating curve (AUC) values. The CatBoost-based prediction model after 26 weeks' gestation performed best with an AUC value of 0.70 (0.67, 0.73), accuracy of 0.81, sensitivity of 0.47, and specificity of 0.83. Number of antenatal care visits before 24 weeks' gestation, aspartate aminotransferase level at registration, symphysis fundal height, maternal weight, abdominal circumference, and blood pressure emerged as strong predictors after 26 completed weeks. The application of machine learning on pregnancy surveillance data is a promising approach to predict preterm birth and we identified several modifiable antenatal predictors.

Genetically predicted selenium concentrations and thyroid function: A two-sample Mendelian randomization study.

OBJECTIVE: The impact of selenium (Se) on human thyroid function remains unclear, with inconsistent results from recent epidemiological studies. Moreover, the observed associations are prone to bias due to potential confounding and reverse causation. Mendelian randomization (MR) analysis facilitates the large minimization of biases produced by environmental and lifestyle influences, providing unconfounded estimates of causal effects using instrumental variables. We aim to examine the association between Se concentrations and human thyroid function using a two-sample MR analysis. DESIGN AND METHODS: Genetic instruments for Se concentrations, including toenail and blood (TAB) and blood Se concentrations, were identified from a genome-wide association study (GWAS) of blood Se (n = 5477) and toenail Se levels (n = 4162). GWAS summary statistics on thyroid phenotypes were downloaded from the ThyroidOmics consortium, including thyroid-stimulating hormone (TSH) (n = 54,288), free thyroxin (FT4) (n = 49,269), hypo (n = 53,423), and hyperthyroidism (n = 51,823). The MR study was conducted using the inverse-variance weighted (IVW) method, supplemented with the weighted median and the mode-based method. RESULTS: Genetically determined TAB Se was negatively associated with FT4 (ß = -.067; 95% confidence interval [CI] = -0.106, -0.028; p = 0.001) using the IVW analyses, as well in the additional analyses using the weighted median and weighted-mode methods. No evidence in heterogeneity, pleiotropy or outlier single-nucleotide polymorphisms was detected (all p > 0.05). Suggestive casual association between increased genetically determined TAB Se concentrations and decreased hypothyroidism risk was found by the IVW method (odds ratio [OR] = 0.847; 95% CI = 0.728, 0.985; p = 0.031). The causal effect of TAB Se on FT4 was observed in women (ß = -.076; 95% CI = -0.129, -0.024; p = 0.004). However, the influence of genetically determined higher Se concentrations on TSH levels and hyperthyroidism revealed insignificance in the primary and sensitivity analyses. CONCLUSIONS: The present MR study indicated that high Se concentration enable the decreasing of FT4 levels, and the effects of Se concentrations on FT4 remain sex-specific.

Associations between seasonal ambient air pollution and adverse perinatal outcomes: a retrospective cohort study in Wenzhou, China.

Prenatal exposure to ambient air pollution has been associated with adverse perinatal outcomes in previous studies. However, few studies have examined the interaction between air pollution and the season of conception on term low birth weight (TLBW) or macrosomia. Birth registry data of singleton live births in Wenzhou, China, between January 2015 and December 2016 were accessed from the Wenzhou Maternal and Child Health Information Management platform, and data on the ambient air pollutants in Wenzhou were obtained from the Chinese Air Quality Online Monitoring and Analysis Platform. Single-/two-pollutant binary logistic regression models were used to assess the associations between ambient air pollutants (PM2.5, PM10, NO2, SO2, and O3) and TLBW/macrosomia, further exploring whether the season of conception interacts with air pollution to impact birth weight. Finally, 213,959 term newborns were selected, including 2452 (1.1%) infants with TLBW and 13,173 (6.1%) infants with macrosomia. In the single-/two-pollutant models, we observed an increased risk of TLBW associated with maternal exposure to PM2.5, PM10, SO2, and NO2 during the entire pregnancy, especially in the 2nd trimester. Maternal exposure to O3 during the 1st trimester was associated with increased macrosomia risk, and O3 exposure during the 3rd trimester was associated with increased TLBW risk. Pregnant women who conceive in the warm season may experience a more adverse ambient air environment that is related to the risks of TLBW. These findings add to the evidence suggesting that air pollution and the season of conception may have synergistic effects on adverse perinatal outcomes, especially TLBW. Further prospective cohort studies are needed to validate our results.

Placental mtDNA copy number and methylation in association with macrosomia in healthy pregnancy.

INTRODUCTION: Fetal growth and development depend on metabolic energy from placental mitochondria. However, the impact of placental mitochondria on the occurrence of macrosomia remains unclear. We aimed to explore the association between macrosomia without gestational diabetes mellitus (non-GDM) and changes in placental mitochondrial DNA (mtDNA) copy number and methylation. METHODS: Fifty-four newborns with macrosomia and 54 normal birthweight controls were enrolled in this study. Placental mtDNA copy number and mRNA expression of nuclear genes related to mitochondrial replication or ATP synthesis-related genes were measured by real-time quantitative polymerase chain reaction (qPCR). Methylation levels of the non-coding regulatory region D-loop and ATP synthesis-related genes were detected by targeted bisulfite sequencing. RESULTS: Newborns with macrosomia had lower placental mtDNA copy number and higher methylation rates of the CpG15 site in the D-loop region (D-CpG15) and CpG6 site in the cytochrome C oxidase III (COX3) gene (COX3-CpG6) than normal birth weight newborns. After adjusting for potential covariates (gestational age, prepregnancy BMI, and infant sex), decreased placental mtDNA copy number (adjusted odds ratio [aOR] = 2.09, 95% confidence interval [CI] 1.03-4.25), elevated methylation rate of D-CpG15 (aOR = 2.06, 95% CI 1.03-4.09) and COX3-CpG6 (aOR = 2.13, 95% CI 1.08-4.20) remained significantly associated with a higher risk of macrosomia. DISCUSSION: Reduced mtDNA copy number and increased methylation levels of specific loci at mtDNA would increase the risk of macrosomia. However, the detailed molecular mechanism needs further identification.

Efficacy and Safety of Laser Surgery and Transurethral Resection of the Prostate for Treating Benign Prostate Hyperplasia: a Network Meta-analysis.

BACKGROUND: Traditional meta-analyses or systematic reviews of randomized controlled trials (RCTs) have been used to compare laser surgeries and transurethral resection of the prostate (TURP) for benign prostate hyperplasia (BHP), but they cannot provide a hierarchy regarding efficacy and safety of treatment. OBJECTIVE: We therefore performed a network meta-analysis (NMA) to compare and create hierarchies for efficacy and safety of TUPR and laser surgeries for BPH. MATERIALS AND METHODS: We searched for reports of RCTs published up to April 25, 2015. After methodological quality assessment and data extraction, we performed an NMA to compare TURP and laser surgeries for BPH. RESULTS: We ranked the treatments of TURP and laser surgeries for BPH. For IPSS at 6 months, holmium laser resection of the prostate (HoLRP) ranked the first-best and at 12 months, holmium laser enucleation of the prostate (HoLEP). For Qmax at 6 and 12 months, HoLEP ranked the first-best; for operative time it was TURP; for cathedral removal time, diode laser enucleation of the prostate (DiLEP) ranked the first-best. CONCLUSIONS: Although TURP is considered the gold standard for treating BPH, it is not better in terms of efficacy and safety compared with the laser surgery. Our NMA created hierarchies for the 9 types of surgery in terms of efficacy and safety, which should help clinicians choose the best approach for the individual patient.

Vitamin B2 intake and the risk of colorectal cancer: a meta-analysis of observational studies.

BACKGROUND: A systematic review and meta-analysis of observational studies evaluated the association of intake of vitamin B2 with the incidence of colorectal cancer. MATERIALS AND METHODS: Relevant studies were identified in MEDLINE via PubMed (published up to April 2014). We extracted data from articles on vitamin B2 and used multivariable-adjusted odds ratio (OR) and a random-effects model for analysis. RESULTS: We found 8 articles meeting the inclusion criteria (4 of cohort studies and 4 of case-control studies) and a total of 7,750 colorectal cancer cases were included in this meta-analysis. The multivariable-adjusted OR for pooled studies for the association of the highest versus lowest vitamin B2 intake and the risk of colorectal cancer was 0.83 (95% confidence interval [95%CI]:0.75,0.91). We performed a sensitivity analysis for vitamin B2. If we omitted the study by Vecchia et al., the pooled OR was 0.86 (95%CI, 0.77,0.96). CONCLUSIONS: This is the first meta-analysis to study links between vitamin B2 and colorectal cancer. We found vitamin B2 intake was inversely associated with risk of colorectal cancer. However, further research and large sample studies need to be conducted to better validate the result.

[Analysis on incidence of bacillary dysentery in Jinan municipality from 1951 to 2005].

OBJECTIVE: To explore the epidemic characteristics of bacterial dysentery in Jinan municipality, and to provide scientific basis for effective strategy for bacterial dysentery control. METHODS: The epidemiological characteristics of bacillary dysentery in Jinan from 1951 to 2005 were analyzed. A total of 485,333 cases in the span of 50 years were recorded, while the population-based case distribution was less than the total cases due to the data incompleteness during the Cultural Revolution. RESULTS: The incidence of bacillary dysentery in Jinan has been decreasing by years with average incidence rate of 283.10/100,000. The significant differences were observed among the incidence rates of various ages(chi2 = 14.99, P < 0.05). There were four epidemic peaks, and all the incidence rates were about 1000/100,000. Age of onset mainly concentrated in the 0-4 years old, 20-years old and 30-years old. In terms of occupational distribution, workers accounted for 30.31%, the living-scattered children accounted for 22.71%, and the farmers accounted for 17.90%. The incidence focus was from July to September, which accounted for 71.57%. The peak of incidence emerged in August. The highest incidence in urban was 550.94/100,000. CONCLUSION: Through the efforts of several generations of health workers, the incidence of bacillary dysentery in Jinan has been basically brought under control. Further step should be taken for the control of bacterial dysentery in urban areas and the management of bacterial dysentery in rural areas. Moreover, the biological characteristics of F2a should be a focus for the future study.