Aim
We performed a meta‐analysis of randomized controlled trials (RCT) and observational studies to answer the two following questions: (i) whether low maternal circulating 25 hydroxyvitamin D ...(25‐OHD) is associated with an increased risk of preterm birth (PTB) or spontaneous PTB (sPTB); and (ii) whether vitamin D supplementation alone during pregnancy can reduce the risk of PTB.
Methods
Literature search was carried out using Pubmed, Web of Science and Embase databases up to June 2016. Pooled OR or relative risk (RR) with 95%CI were computed using fixed or random effects models depending on the size of heterogeneity. Subgroup analysis was used to explore potential sources of between‐study heterogeneity. Publication bias was evaluated using Egger's test and Begg's test.
Results
Twenty‐four articles (six RCT and 18 observational studies) were identified. Maternal circulating 25‐OHD deficiency (pooled OR, 1.25; 95%CI: 1.13–1.38) rather than insufficiency (pooled OR, 1.09; 95%CI: 0.89–1.35) was associated with an increased risk of PTB, and vitamin D supplementation alone during pregnancy could reduce the risk of PTB (pooled RR, 0.57; 95%CI: 0.36–0.91). This was also the case for the sPTB subgroup (circulating 25‐OHD <50 vs >50 nmol/L; pooled OR, 1.45; 95%CI: 1.20–1.75).
Conclusions
Maternal circulating 25‐OHD deficiency could increase PTB risk and vitamin D supplementation alone during pregnancy could reduce PTB risk. Extrapolation of the results, however, must be done with caution, and there is urgent need for larger, better‐designed RCT to confirm this effect.
Abstract Purpose Little is known about patterns of active commuting to school (ACS) among school-aged children in China. This study examines mode of transport to school in China and associations with ...physical and mental well-being among national representative children. Methods Data came from National Puberty Research Collaboration. Commuting mode to school was self-reported and categorized as three categories: walking, cycling, and passive commuting to school. Body mass index, percentage body fat (PBF, measured by skinfold thickness), waist circumference (WC) was measured, and depressive symptoms was assessed by Children's Depression Inventory. Results A total of 12,151 girls and 9,445 boys from grade 4 to grade 12 participated in this study. Totally 39.9% of Chinese children walked and 15.9% cycled to school, 44.2% traveled by passive commuting mode. ACS was predictive of lower body mass index, PBF, and WC. Children who commuted via active modes had body mass index, PBF, and WC scores of .167 (95% confidence interval CI .274–.060), .566 (95% CI .270–.862), and .724 (95% CI .423–1.025) points lower, respectively, than those who used passive transport. ACS was associated with .855 lower odds of being obese ( p < .001) and .907 lower ( p < .001) odds of having depressive symptoms compared with children using passive transport. Conclusions ACS is correlated with better physical and mental well-being. Sustainable transport planning aimed at increasing active travel to school among Chinese children and adolescents is in great need.
Abstract Background Previous studies concerning the association between maternal anxiety during pregnancy and adverse birth outcomes have provided controversial findings. Methods In this systematic ...review, a meta-analysis was utilized to investigate the association between maternal anxiety and preterm birth (PTB) and/or low birth weight (LBW). Literature was searched until June 2013. Only prospective cohort studies that reported data on maternal anxiety during pregnancy with PTB and/or LBW were included. Pooled relative risks (RRs) with 95% confidence intervals (CIs) were calculated using fixed or random effects models depending on the size of heterogeneity. Results Twelve studies totaling 17,304 pregnant women reported PTB data; and six studies totaling 4948 pregnant women reported LBW data. Maternal anxiety during pregnancy was associated with significant increased risk of PTB (pooled RR=1.50, 95% CI=1.33–1.70) and LBW (pooled RR=1.76, 95% CI=1.32–2.33). Limitations Potential moderators could not be adequately considered due to insufficient information. In addition, the effects of different types of anxiety disorder on the risk of these adverse birth outcomes could not be investigated. Conclusions The results suggested that maternal anxiety during pregnancy was positively related to an increased risk of PTB and LBW. Healthcare providers should give close attention to anxiety in pregnant women and provide appropriate mental health support in order to improve outcomes for both mothers and infants.
The relationship of intrauterine phthalate exposure with gestational metabolic syndrome (GMS) parameters is inconsistently reported. We performed a systematic review to evaluate the association ...between prenatal phthalate exposure and GMS parameters. A literature search was performed in three databases. According to the defined PECOS statement, eligible studies were identified. The method and result for each study was qualitatively summarized with great emphasis on study design and exposure assessment. Fourteen studies were included in the present systematic review. Two studies used one-spot serum sample for evaluation of phthalate exposure, while others used 1–4 urine samples. Concentrations of phthalate metabolites varied substantially, and the levels in serum were greatly lower than those in urine. These studies observed no interstudy or intrastudy consistency for association between phthalates and GMS in pregnant women cross-sectionally or longitudinally, regardless of phthalates species or GMS indicator. Most reported associations were not significantly different from null result. Besides, positive and negative relationships also existed. The current epidemiological data do not support the hypothesis that prenatal exposure to phthalates increases GMS risk.
Context:
There are a few prospective population-based cohort studies evaluating the effects of maternal thyroid dysfunctions on fetal and infant developments, but they are inconsistent.
Objective:
...The objective of the study was to investigate the effects of maternal thyroid dysfunction on fetal and infant development.
Setting and Participants:
The study was nested within a prospective population-based China-Anhui Birth Defects and Child Development study. A total of 1017 women with singleton pregnancies participated in this study. Maternal serum samples in the first 20 wk of pregnancy were tested for thyroid hormones (TSH and free T4). Pregnant women were classified by hormone status into percentile categories based on laboratory assay and were compared accordingly.
Main Outcomes:
Outcomes included fetal loss, malformation, birth weight, preterm delivery, fetal stress, neonatal death, and infant development.
Results:
Clinical hypothyroidism was associated with increased fetal loss, low birth weight, and congenital circulation system malformations; the adjusted odds ratios 95% confidence interval (CI) were 13.45 (2.54–71.20), 9.05 (1.01–80.90), and 10.44 (1.15–94.62), respectively. Subclinical hypothyroidism was associated with increased fetal distress, preterm delivery, poor vision development, and neurodevelopmental delay; the adjusted odds ratios (95% CI) were 3.65 (1.44–9.26), 3.32 (1.22–9.05), 5.34 (1.09–26.16), and 10.49 (1.01–119.19), respectively. Isolated hypothyroxinemia was related to fetal distress, small for gestational age, and musculoskeletal malformations; the adjusted odds ratios (95% CI) were 2.95 (1.08–8.05), 3.55 (1.01–12.83), and 9.12 (1.67–49.70), respectively. Isolated hyperthyroxinemia was associated with spontaneous abortion; the adjusted odds ratio (95% CI) was 6.02 (1.25–28.96). Clinical hyperthyroidism was associated with hearing dysplasia; the adjusted odds ratio (95% CI) was 12.14 (1.22–120.70).
Conclusions:
Thyroid dysfunction in the first 20 wk of pregnancy may result in fetal loss and dysplasia and some congenital malformations.
Accumulating evidence have investigated the effects of nighttime light exposure on sleep problems. Nevertheless, the evidence of the relationship between light at night (LAN) and sleep problems ...remains scarce and inconsistent.
Conducted a systematic review and meta-analysis based on observational studies to examine the association between LAN exposure and sleep problems among human subjects.
We systematically searched three databases (PubMed, Web of Science, and Embase) to identify potentially eligible studies through May 25, 2022. The risk of bias and the quality of the generated evidence were assessed by two authors using the National Toxicology Program's Office of Health Assessment and Translation (OHAT) risk of bias rating tool and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) guideline. Random-effects model was applied to synthesize the risk estimates across eligible studies. The heterogeneity of included studies was quantified by the statistics of I2.
A total of 7 cross-sectional studies comprising 577,932 participants were included. Individuals with higher levels of LAN exposure were associated with a 22 % (Summary Odds Ratio, SOR: 1.22, 95 %CI: 1.13–1.33) increased prevalence of sleep problems. The pooled effect size of indoor LAN exposure (SOR: 1.74, 95%CI: 1.27–2.37) associated with sleep problems was significantly higher than outdoor LAN exposure (SOR: 1.19, 95%CI: 1.11–1.29; P = 0.022). Additionally, dose-response analysis demonstrated that LAN intensity threshold exceeding 5.8 nW/cm2/sr (SOR: 1.04, 95%CI: 1.01–1.07) had a significant effect on sleep problems and the prevalence of sleep problems was increasing with increase in LAN intensity.
Overall, our findings support the detrimental effects of LAN exposure on sleep. Maintaining bedroom darkness at night may be a feasible measure to reduce the prevalence of sleep problems. Future longitudinal studies with more advanced LAN assessment methods are required to move the field forward.
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•Increasing evidence showed that LAN exposure is associated with sleep problem.•Studies on the effects of nighttime light exposure on sleep problem are inconsistent.•Higher LAN exposure was associated with a 22 % increased prevalence of sleep problem.•Keeping bedroom dark at night may be an important strategy for reducing sleep problem risk.
Context:
Vitamin D deficiency is common in pregnant women. Nevertheless, the association between maternal vitamin D status during pregnancy and the risk of having small for gestational age (SGA) and ...low birth weight (LBW) infants is uncertain.
Objective:
The objective of this study was to investigate whether there is a correlation between maternal vitamin D deficiency during pregnancy and the risk of having SGA and LBW infants in a Chinese population.
Design and Participants:
This was a population-based birth cohort study that recruited 3658 eligible mother-and-singleton-offspring pairs.
Main Outcome Measures:
Serum 25-hydroxyvitamin D was measured by RIA. The rate and relative risk (RR) for SGA and LBW infants were calculated among subjects with vitamin D deficiency and insufficiency during pregnancy.
Results:
There was a positive correlation between maternal serum 25-hydroxyvitamin D level and offspring birth weight (r = 0.477; P < .001). Further analysis showed that 4.98% of neonates were LBW infants among the subjects with vitamin D deficiency (RR, 12.00; 95% confidence interval CI, 4.37, 33.00) and 1.32% among the subjects with vitamin D insufficiency (RR, 3.18; 95% CI, 1.07, 9.48). After adjustment for confounders, the RR for LBW infants was 12.31 (95% CI, 4.47, 33.89) among subjects with vitamin D deficiency and 3.15 (95% CI, 1.06, 9.39) among subjects with vitamin D insufficiency. Moreover, 16.01% of neonates were SGA infants among subjects with vitamin D deficiency (RR, 5.72; 95% CI, 3.80, 8.59) and 5.59% among subjects with vitamin D insufficiency (RR, 1.99; 95% CI, 1.27, 3.13). After adjustment for confounders, the RR for SGA infants was 6.47 (95% CI, 4.30, 9.75) among subjects with vitamin D deficiency and 2.01 (95% CI, 1.28, 3.16) among subjects with vitamin D insufficiency.
Conclusion:
Maternal vitamin D deficiency during pregnancy elevates the risk of SGA and LBW infants in a Chinese population.
•We evaluated the effect of prenatal phthalate exposure on children cognitive development by repeated measure analysis.•The first trimester might be the most critical period of cognitive development ...in term of exposure to phthalate.•VCI and VSI might be more susceptible to phthalates exposure than other domains.•A gender-specific effect may exist between prenatal phthalates exposure and IQ.
Phthalates are a group of heavily produced endocrine disruptors that are widely used in personal care products, food packaging, building materials, and medical device. Few epidemiological studies have examined the effect of repeated prenatal exposure to multiple phthalates on preschooler cognitive development.
This study aimed to examine the association between prenatal phthalate exposure measured at multiple time points and the intelligent quotient (IQ) scores of preschoolers, and to further identify the critical windows and specific intelligence domains in which phthalate exposure would affect preschooler cognitive development.
The current study was based on the Ma’anshan Birth Cohort (MABC) study. Seven phthalate metabolites were measured in 2128 maternal urine samples collected during the first, second, and third trimesters of pregnancy. The IQ score of preschool-aged children were assessed with the Chinese version of the Wechsler Preschool and Primary Scale of Intelligence, Fourth edition (WPPSI-Ⅳ CN). Linear mixed models (LMMs) were used to assess the longitudinal effects of repeated prenatal phthalate exposure on children’s IQ score. Multiple linear regression models were fitted to determine whether critical window phthalate exposure would affect cognitive development of children.
Overall, the repeated measures analysis indicated that the verbal comprehension index (VCI), visual space index (VSI) and full-scale intelligence quotient (FSIQ) decreased by 0.30 (95% CI: −0.60, 0; p = 0.05), 0.32 (95% CI: −0.62, −0.01; p = 0.04), and 0.31 (95% CI:-0.57, −0.04; p = 0.02) points, respectively, with each ln-transformed increase in the metabolite concentration of MBP. The fluid reasoning index (FRI) and processing speed index (PSI) increased by 0.30 (95% CI: 0.07, 0.54; p = 0.01) and 0.28 (95% CI: 0.06, 0.51; p = 0.01) points, respectively, with each ln-concentration increase in MEP. Trimester-specific regression models stratified by the sample collection time during pregnancy generated consistent results. In the first trimester, each ln-transformed MBP increase was associated with reductions in VCI, VSI and FSIQ of 0.56 (95% CI:-1.09, −0.02; p = 0.04), 0.60 (95% CI:-1.15, −0.05; p = 0.03) and 0.49 (95% CI:-0.97, −0.01; p = 0.04) points, respectively. In the third trimester, we observed that only MBzP exposure was associated with an increase in VCI (β: 0.48, 95% CI: 0.03, 0.92; p = 0.04). The gender-stratified analyses revealed that boys drove these associations.
Our results suggest that prenatal phthalate exposure impairs the cognitive development of preschoolers. The first trimester of pregnancy might be the most vulnerable period in terms of neurotoxicitydue to phthalate exposure. These findings warrant further confirmation.
Previous studies have found associations between single toxic metals, such as arsenic and cadmium, and kidney function in adults with diabetes. However, studies with regards to other metals and metal ...mixtures are still limited.
Our study aimed to investigate the associations between urinary concentrations of 5 selected metals and metal mixtures and kidney function using a sample of older adults with diabetes mellitus in Chinese communities.
In a sample of older adults (n = 5186), 592 eligible subjects were included in this study. Urinary concentrations of 5 metals, i.e., arsenic (As), cadmium (Cd), vanadium (V), cobalt (Co), and thallium (Tl), were measured by inductively coupled plasma mass spectrometer (ICP-MS). Estimated glomerular filtration rate (eGFR) was calculated and dichotomized into indicator of chronic kidney disease (CKD). Logistic analysis and Bayesian kernel machine regression (BKMR) were used to explore the associations between single metals and metal mixtures and CKD, respectively.
Urinary levels of As and V were positively correlated with CKD (OR=2.37, 95% CI: 1.31–4.30 for As; OR=2.24, 95% CI: 1.25–4.03 for V), when compared the 4th quartile with the 1st quartile. After adjustment for potential confounders, the significant association between As and CKD still existed (OR=2.73, 95% CI: 1.23–6.07). BKMR analyses showed strong linear positive associations between As and V and CKD. Higher urinary levels of the mixture were significantly associated with higher odds of CKD in a dose-response pattern. As and V showed the highest posterior inclusion probabilities.
Urine As and V were positively associated with CKD in older adults with diabetes mellitus, separately and in a mixture. The metals mixture showed a linear dose-response association with the odds of CKD. The analyses of mixtures, rather than of single metals, may provide a real-world perspective on the relationship between metals and kidney function.
•Urine As and V were significantly associated with CKD in single metal models.•The overall harmful effects of 5 selected metals on kidney function were observed.•As and V made major contributions to kidney function among mixtures.
The evidence about the effect of essential trace element (ETE) mixture on cognitive function amongst older adults is limited. This study aims to evaluate the associations of single ETEs and ETE ...mixture with cognitive function using a representative sample of community-dwelling older adults in China.
A total of 3814 older adults were included in the study. Urinary concentrations of selenium (Se), vanadium (V), cobalt (Co), strontium (Sr), and molybdenum (Mo) were detected by inductively coupled plasma mass spectrometry. Cognitive function in older adults was assessed using the Chinese version of the Mini-Mental State Examination (MMSE). Linear regression and Bayesian kernel machine regression (BKMR) were performed to explore the associations of single ETEs and ETE mixture with cognitive function, respectively.
Linear regression showed that urinary levels of Se and V were positively associated with MMSE scores in the adjusted single-element models. BKMR also showed marginally positive associations of Se and V with MMSE scores. Moreover, higher urinary levels of ETE mixture were significantly associated with increased MMSE scores in a dose-response pattern, and Se was the most important contributor within the mixture. Both Se and V demonstrated positive additive effects on the associations of other ETEs with MMSE scores, whereas Co had a negative additive effect.
V and Se are positively associated with cognitive function, individually and as a mixture. ETE mixture exhibits a linear dose-response association with improved cognitive function, with Se being the most important component within the mixture. Mixture analyses rather than single ETE analyses may provide a real-world perspective on the relationship between ETE mixture and cognitive function. Further cohort studies are needed to clarify the association of multiple ETEs with cognitive function.
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•Se and V were positively associated with MMSE scores, separately and in a mixture.•Higher levels of ETE mixture were associated with increased MMSE scores.•Se was the most beneficial contributor to cognitive function within the mixture.
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