Global trends in total fertility rate and its relation to national wealth, life expectancy and female education.

OBJECTIVES: Along with the development of the times and progress of the society, the total fertility rate (TFR) markedly changed in each country. Therefore, it is critical to describe the trend of TFR and explore its influencing factors. However, previous studies did not consider the time lag and cumulative effect in the associations between the influencing factors and TFR. Thus, our study aimed to analyze the associations from a new dimension. METHODS: The study was employed using national-level data from the World Bank and United Nations Development Programme. Distributed lag non-linear models with 5-year lag were used to examine the independent associations between the relevant factors and TFR. RESULTS: The cumulative exposure-TFR curves were inverted U-shaped for log gross domestic product (GDP) per capita and life expectancy at birth, while the cumulative exposure-response curves were approximately linear for female expected years of schooling and human development index (HDI). However, it is worth noting that in the developed regions, TFR increased slightly with the high level of GDP per capita, female expected years of schooling and HDI. CONCLUSIONS: Nowadays, with the growth of GDP per capita, life expectancy at birth, female expected years of schooling and HDI, TFR are on a drastic downward trend in most regions. Besides, with the development of society, when levels of the factors continued to increase, TFR also showed a slight rebound. Therefore, governments, especially those in developing countries, should take measures to stimulate fertility and deal with a series of problems caused by declining TFR.

Descriptive study of foodborne disease using disease monitoring data in Zhejiang Province, China, 2016-2020.

BACKGROUND: This study aimed to identify the epidemiology, seasonality, aetiology and clinical characteristics of sporadic foodborne diseases in Zhejiang province during 2016-2020. METHODS: Descriptive statistical methods were used to analyze the data from surveillance network established by the Zhejiang Provincial Center for Disease Control and Prevention. There were 31 designated hospitals in all 11 cities which were selected using probability proportionate to size sampling method. RESULTS: During the study period, the surveillance system received 75,124 cases with 4826 (6.42%) hospitalizations from 31 hospitals. The most common cause was Norovirus, 6120 cases (42.56%), followed by Salmonella, 3351 cases (23.30%). A significant seasonal trend was observed for the V. parahaemolyticus, with the highest rates over the summer period, peaking in August, 1171 cases (38.75%), a similar trend was also observed with Salmonella and Diarrheagenic E. coli. Norovirus infections showed the highest rate in November (904, 14.77%) and March (660,10.78%), the lowest in August, 215 cases (3.51%). Patients between 19 ~ 40 years were more likely to infected by Norovirus, V. parahaemolyticus and Diarrheagenic E. coli, patients below 1 year were the highest among patients with Salmonella infection, 881 cases (26.3%). The Norovirus, V. parahaemolyticus and Diarrheagenic E. coli infection with the highest positive detection rates among the workers were observed. The largest number cases of food categories were from aquatic product infection. The private home was the most common exposure setting. CONCLUSION: Our study highlighted the necessity for conducting an active, comprehensive surveillance for pathogens in all age groups, to monitor the changing dynamics in the epidemiology and aetiology of foodborne diseases to guide policies that would reduce related illnesses.

Association of nausea and vomiting of pregnancy with infant growth in the first 24 months of life.

PURPOSE: We aimed to investigate the association of maternal nausea and vomiting during pregnancy (NVP) with infant growth in the first 24 months of life and compare the effect of fetal gender. METHODS: This prospective cohort study was conducted in Zhoushan Maternal and Child Health Hospital, Zhejiang, from 2011 to 2018. 1942 pairs of singleton newborns and their mothers were selected as participants. Main outcomes were gestational weight gain (GWG), birth outcomes (birthweight and gestational age) and infant growth [weight, height, weight/height-for-age Z score (WAZ/HAZ), the weight gain during childhood]. The associations of NVP with birth outcomes and infant growth at children's age of 1, 3, 6, 12, 18, and 24 months were analyzed by multivariable regression models. RESULTS: Of the 1942 women, 1395 had NVP at first trimester (T1) and among them, 210 still experienced NVP at second trimester (T2). Compared with women without NVP, women experienced severe NVP at T1 were related with lower total GWG. Mild and moderate NVP at T1 were negatively associated with lower birthweight among women with male infants. Female infants exposed to maternal NVP at T1, especially for severe degree, were showed greater weight, WAZ, height, HAZ, and weight gain after 1 year old (at age of 12, 18, 24 months). No association between maternal NVP and infant growth was observed among male infants. CONCLUSION: Exposure to NVP at T1 was, respectively, associated with lower GWG. Favorable influence of NVP at T1 on infant growth was observed among female offspring.

[Analysis on the pollution characteristics and influence factors of PM_(2. 5) in Shenzhen City in 2016].

OBJECTIVE: To explore the pollution characteristics and possible influence factors of PM_(2. 5)in Shenzhen in 2016. METHODS: The dynamic characters of PM_(2. 5)mass concentration were analyzed using air quality monitoring and meteorology observation data. The correlations between PM_(2. 5)and other affecting factors, e. g. gas pollutions and meteorology factors, were discussed. A multiple linear regression model was built to reveal the impacts of those factors on PM_(2. 5)concentrations in Shenzhen City using the air quality monitoring and meteorology observation data. RESULTS: The mass concentration of PM_(2. 5)was(27. 02±13. 88)µg/m~3, and the ratios of PM_(2. 5)/PM_(10)was(0. 62±0. 08)in Shenzhen City. Significant positive correlations existed between PM_(2. 5)concentration and main airpollutants(NO_2, SO_2, CO and O_3)(P<0. 05). A significant negative correlation existed between PM_(2. 5) concentration and temperature, relative humidity(P<0. 05), and also a significant positive correlation between atmospheric pressure and PM_(2. 5)concentration. The multiple linear regression showed that air pollutants(NO_2, SO_2, CO, and O_3)and atmospheric pressure could explain 86. 7% of the variations of PM_(2. 5)concentration. The standard regression coefficient of CO in the model was the highest(0. 439). CONCLUSION: PM_(2. 5)pollution was relatively light in Shenzhen City, and PM_(2. 5)was the main component of inhalable particulate matter. Atmospheric pressure and other pollutants in the atmosphere were the main influencing factors of PM_(2. 5)concentration, and CO was the major contributor to PM_(2. 5)concentration rising in Shenzhen City.

[Temporal and spatial distribution of air pollution in Shenzhen City during 2014-2016].

OBJECTIVE: To investigate spatial-temporal distribution characteristics of air quality indexes( AQI) in Shenzhen City and provide scientific basis for control of air pollution. METHODS: The monitoring data of AQI collected at the 19 monitoring posts in Shenzhen City from 2014 to 2016 were pooled and analyzed, and daily, seasonal and annual means of AQI at each monitoring post were forked out. The theory of spatial autocorrelation analysis was adopted in analyzing strength of the spatial autocorrelation and spatial clustering patterns of AQI. RESULTS: The median of AQI of Shenzhen City was50. 0, and the air quality level of Shenzhen City was level 2. PM_(2. 5) was the primary air pollutant in 2014, and O_3 was the primary air pollutant in 2015 and 2016 respectively. From the time distribution, the air quality in Shenzhen City was the worst in the winter but the best in the summer, and the air quality in night was worse than the day. Spatial autocorrelation analysis showed that there was positive spatial autocorrelation of AQI in Shenzhen. The global moran's I of AQI was 0. 167( Z = 2. 000, P < 0. 05), and the greary coefficient was 0. 801( Z = 1. 711, P < 0. 05). The local moran's I of AQI was 1. 027( P < 0. 05) in Guangming New District. The moran scatter plot of AQI in Guangming New District was in the first quadrant, and appeared to be in a high-high clustering pattern. The moran scatter plot of AQI in Yantian District was in the third quadrant, and appeared to be in a low-low clustering pattern. CONCLUSION: The air quality of Shenzhen City was better. PM_(2. 5) and O_3 were the primary air pollutant. It is necessary to emphasize and strengthen the prevention and control of air pollution in Winter, especially in several administrative districts of the northwest of Shenzhen City.

Efficacy of intermittent versus daily vitamin D supplementation on improving circulating 25(OH)D concentration: a Bayesian network meta-analysis of randomized controlled trials.

Background: Vitamin D deficiency is a widespread issue globally, resulting in increased use of vitamin D supplements. However, it is unclear whether intermittent (weekly or monthly) vitamin D supplementation is as effective as daily supplementation in improving circulating 25-hydroxyvitamin D [25(OH)D] levels. Methods: Three databases including Medline, EMBASE, and the Cochrane Library were systematically searched up to 10 November 2020. The risk of bias was evaluated according to Cochrane Collaboration's tool for rating methodological quality assessment. Direct and indirect comparisons between interventions and controls were performed by a Bayesian network meta-analysis (NMA), where the mean difference (MD) and its 95% confidence interval (CI) were used to indicate the efficacy. Results: This NMA analysis included 116 RCTs with a total of 11,376 participants. Generally, we observed that 25(OH)D concentrations were significantly elevated regardless of vitamin D supplementation frequency. Although the findings of SUCRA indicated that daily vitamin D supplementation had a higher rank value than intermittent supplementation when the supplement dosage was similar, no statistically significant pooled mean differences of 25(OH)D concentration were noted between the daily supplementation group and intermittent supplementation group. Additionally, weekly supplementation with a total of 600,000 IU vitamin D supplementation during 3 months had the best efficacy in elevating 25(OH)D concentration (pooled MD = 63 nmol/L, 95%CI: 49-77). To achieve optimal 25(OH)D concentration (>75 nmol/L), we recommend 60,000 IU vitamin D supplementation monthly (~2,000 IU/day). Conclusion: The efficacy of intermittent vitamin D supplementation was similar to daily supplementation. Coupled with its convenience, the frequency and dosage of intermittent vitamin D supplements were recommended to reach the optimal 25(OH)D level.Systematic review registration:https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=257257, PROSPERO CRD42021257257.

Association of vitamin D and gene variants in the vitamin D metabolic pathway with preterm birth.

OBJECTIVES: The aim of this study was to explore the association of vitamin D (VitD) levels during pregnancy and its metabolic pathway genes with the risk for preterm birth (PTB) among pregnant women in southeast China. METHODS: This study was conducted in Zhoushan Maternal and Child Health Hospital, Zhejiang, from August 2011 to May 2018. Plasma 25-hydroxyvitamin vitamin D [25(OH)D] levels in three trimesters and single-nucleotide morphisms in the VitD metabolic pathway were measured. Relevant information was collected using questionnaires and an electronic medical recorder system. Multiple statistical methods including linear regression, logistic regression, and crossover analysis were applied. RESULTS: The prospective cohort study included 3465 pregnant women, of which 202 were PTB (week of gestation at delivery: 33.38 ± 4.05), accounting for 5.8%. After adjusting for potential confounders, VitD sufficiency (≥30 ng/mL) in the second and third trimesters was associated with longer gestational age at delivery compared with VitD deficiency (<20 ng/mL). However, no significant association was found between VitD with the risk for PTB. rs7041, rs10210408, and rs2228171 were associated with gestational week and the risk for PTB. Significant associations were found of rs10210408, rs2209314, rs1155563, rs2544381 and the status of VitD in the second and third trimester with the gestational week. We also found that rs7041 and VitD in the second trimester might exert interaction on gestational week and the risk for PTB (Pinter = 0.038; Pinter = 0.019); rs16846876 and VitD in the second trimester might exert interaction on gestational week (Pinter = 0.024); rs4334089 and VitD in the third trimester might exert interaction on gestational week (Pinter = 0.024). Similar results were found when we tested pregnant women's plasma 25(OH)D in the first and second trimesters. CONCLUSIONS: Women with VitD deficiency were associated with shorter gestational weeks. Single-nucleotide morphisms in VitD metabolic pathway genes were significantly associated with gestation week and the risk for PTB, mainly in vitamin D-binding protein (GC) and low-density lipoprotein-related protein 2 (LRP2)genes. Additionally, maternal VitD with GC gene and maternal VitD with vitamin D receptor (VDR) gene might exert interactions on the risk for PTB.

Association of vitamin D pathway gene polymorphisms with vitamin D level during pregnancy was modified by season and vitamin D supplement.

BACKGROUND & AIMS: This study aims to explore the associations of vitamin D (VD) metabolic pathway gene with 25(OH)D level in pregnant women and the interactions of SNP with season and VD supplement. METHODS: A total of 2658 pregnant women were selected from Zhoushan Pregnant Women Cohort study. Gestational 25(OH)D level and single nucleotide polymorphism (SNP) of VD metabolic pathway gene were detected. Multilinear regression models were used to estimate associations of SNPs with gestational 25(OH)D levels. Stratified analyses were performed to test the interactions of SNP with season and VD supplements. RESULTS: The mutations of rs2298849 and rs7041 on the GC gene were respectively associated with higher 25(OH)D in the first and third trimester; the mutations of seven SNPs (rs1155563, rs16846876, rs17467825, rs2282679, rs2298850, rs3755967, and rs4588) on the GC gene were respectively associated with lower 25(OH)D both in the first and third trimester, and lower changes in 25(OH)D during late pregnancy. The mutations of above seven SNPs, except for rs1155563, were also respectively associated with lower 25(OH)D in the second trimester, but to a lesser extent; Besides, pregnant women with mutation on CYP24A1-rs2209314 had a higher increment in 25(OH)D than their counterparts in the second trimester. The increasing dose effect of Gc isoform on 25(OH)D was observed. The associations of GC and LRP2 genes with 25(OH)D modified by season and VD supplements. CONCLUSIONS: The polymorphisms of VD metabolic pathway gene were associated with gestational 25(OH)D, and the associations differ by seasons and VD supplements. Gc isoform exerted a profound influence on gestational 25(OH)D.

Efficacy and Safety of COVID-19 Vaccines in Phase III Trials: A Meta-Analysis.

Nowadays, the vaccination with COVID-19 vaccines is being promoted worldwide, professionals and common people are very concerned about the efficacy and safety of COVID-19 vaccines. No published systematic review and meta-analysis has assessed the efficacy and safety of the COVID-19 vaccines based on data from phase III clinical trials. Therefore, this study has estimated the efficacy and safety of COVID-19 vaccines and the differences between vaccine types. PubMed, Embase, the Cochrane Library, CNKI, Wanfang, medRxiv databases and two websites were used to retrieve the studies. Random-effects models were used to estimate the pooled efficacy and safety with risk ratio (RR). A total of eight studies, seven COVID-19 vaccines and 158,204 subjects were included in the meta-analysis. All the vaccines had a good preventive effect on COVID-19 (RR = 0.17, 95% CI: 0.09-0.32), and the mRNA vaccine (RR = 0.05, 95% CI: 0.03-0.09) was the most effective against COVID-19, while the inactivated vaccine (RR = 0.32, 95% CI: 0.19-0.54) was the least. In terms of safety, the risk of overall adverse events showed an increase in the vaccine group after the first (RR = 1.46, 95% CI: 1.03-2.05) or second (RR = 1.52, 95% CI: 1.04-2.20) injection. However, compared with the first injection, the risk of local (RR = 2.64, 95% CI: 1.02-6.83 vs. RR = 2.25, 95% CI: 0.52-9.75) and systemic (RR = 1.33, 95% CI: 1.21-1.46 vs. RR = 1.59, 95% CI: 0.84-3.01) adverse events decreased after the second injection. As for the mRNA vaccine, the risk of overall adverse events increased significantly, compared with the placebo, no matter whether it was the first (RR = 1.83, 95% CI = 1.80-1.86) or the second (RR = 2.16, 95% CI = 2.11-2.20) injection. All the COVID-19 vaccines that have published the data of phase III clinical trials have excellent efficacy, and the risk of adverse events is acceptable. The mRNA vaccines were the most effective against COVID-19, meanwhile the risk and grade of adverse events was minimal, compared to that of severe symptoms induced by COVID-19.

The Association of Gene Variants in the Vitamin D Metabolic Pathway and Its Interaction with Vitamin D on Gestational Diabetes Mellitus: A Prospective Cohort Study.

The present prospective study included 2156 women and investigated the effect of gene variants in the vitamin D (VitD) metabolic and glucose pathways and their interaction with VitD levels during pregnancy on gestational diabetes mellitus (GDM). Plasma 25(OH)D concentrations were measured at the first and second trimesters. GDM subtype 1 was defined as those with isolated elevated fasting plasma glucose; GDM subtype 2 were those with isolated elevated postprandial glucose at 1 h and/or 2 h; and GDM subtype 3 were those with both elevated fasting plasma glucose and postprandial glucose. Six Gc isoforms were categorized based on two GC gene variants rs4588 and rs7041, including 1s/1s, 1s/2, 1s/1f, 2/2, 1f/2 and 1f/1f. VDR-rs10783219 and MTNR1B-rs10830962 were associated with increased risks of GDM and GDM subtype 2; interactions between each other as well as with CDKAL1-rs7754840 were observed (Pinteraction < 0.05). Compared with the 1f/1f isoform, the risk of GDM subtype 2 among women with 1f/2, 2/2, 1s/1f, 1s/2 and 1s/1s isoforms and with prepregnancy body mass index ≥24 kg/m2 increased by 5.11, 10.01, 10, 14.23, 19.45 times, respectively. Gene variants in VitD pathway interacts with VitD deficiency at the first trimester on the risk of GDM and GDM subtype 2.

Hemoglobin concentration and iron supplement during pregnancy were associated with an increased risk of gestational diabetes mellitus.

BACKGROUND: Hemoglobin (Hb) measurement is a conventional test during perinatal visits. Hb concentration is related to iron supplement. However, studies focusing on Hb levels, iron supplement, and pregnancy outcomes are scarce. This study aimed to determine whether Hb levels and iron supplement were associated with the risk of gestational diabetes mellitus (GDM). METHODS: A running hospital-based cohort was conducted from August, 2011. The demographic data and medical information were collected individually through questionnaires and patient medical records. Multiple linear regression was applied for the association between Hb levels, iron supplement, and blood glucose. Multiple logistic regression was used for evaluating odds ratios between Hb levels, iron supplement, and GDM. RESULTS: Hb levels during first (T1) and second trimester (T2) of pregnancy were significantly and positively associated with blood glucose and GDM risk. After adjusting for age, prepregnancy body mass index, and other risk factors, pregnant women with Hb ≥ 11 g/dL and iron supplement had higher postprandial blood glucose at 1 hour (Hb ≥ 11 g/dL in T2 and iron supplement in T1: ß = 0.860，P = <0.001; Hb ≥ 11 g/dL in T2 and iron supplement in T2: ß = 0.960，P < 0.001; Hb ≥ 11 g/dL in T1 and iron supplement in T2: ß = 1.133, P = 0.033) and GDM risks (odds ratio [OR] = 1.53, 95% confidence interval [CI]: 1.05-2.24; OR = 1.92, 95% CI: 1.13-3.35; OR = 2.15, 95% CI: 1.07-4.34, respectively), compared with those with Hb < 11 g/dL and without iron supplement. CONCLUSION: High Hb concentration and iron supplements without anemia increased postprandial blood glucose and risks for GDM. It indicates that pregnant women with good Hb levels should not be advised to take iron supplements during pregnancy.

Anemia and Diabetic Kidney Disease Had Joint Effect on Diabetic Retinopathy Among Patients With Type 2 Diabetes.

Purpose: Whether the association between diabetic kidney disease (DKD) and diabetic retinopathy (DR) in patients with type 2 diabetes mellitus (T2DM) is leveraged by anemia remains unclear. This study is to evaluate the joint effect of DKD and anemia on DR. Methods: Data were collected from electronic medical records of 1389 patients with T2DM in the Yiwu Central Hospital of Zhejiang Province from 2018 to 2019. Based on retinal examination findings, patients were classified as without diabetic retinopathy (non-DR), non-proliferative diabetic retinopathy (NPDR), and proliferative diabetic retinopathy (PDR). Odds ratio (OR) from multinomial logistic regression models adjusting for potential risk factors of DR were used to evaluate associations of DKD, renal function measures, and anemia with risk of NPDR and PDR. Path analysis was performed to help understand the association of DKD and hemoglobin (Hb) with DR. Results: The study included 901 patients with non-DR, 367 patients with NPDR and 121 patients with PDR. Both high DKD risk and abnormal renal function measures were significantly associated with PDR. Anemia was associated with increased risk of NPDR (OR = 1.75, 95% confidence interval [CI] = 1.18-2.58) and PDR (OR = 3.71, 95% CI = 2.23-6.18). DKD severity and anemia had joint effect on NPDR (OR = 2.29, 95% CI = 1.32-3.96) and PDR (OR = 11.31, 95% CI = 5.95-21.51). These associations were supported by path analysis. Conclusions: DKD severity, abnormal estimated glomerular filtration rate (eGFR), and urinary albumin/creatinine ratio (UACR) were associated with increased risk of DR in patients with T2DM, and anemia had joint effect on these associations. Improving Hb level may decrease the risk of DR in patients with T2DM.