Combining single-cell RNA sequencing and population-based studies reveals hand osteoarthritis-associated chondrocyte subpopulations and pathways

Hand osteoarthritis is a common heterogeneous joint disorder with unclear molecular mechanisms and no disease-modifying drugs. In this study, we performed single-cell RNA sequencing analysis to compare the cellular composition and subpopulation-specific gene expression between cartilage with macroscopically confirmed osteoarthritis (n = 5) and cartilage without osteoarthritis (n = 5) from the interphalangeal joints of five donors. Of 105 142 cells, we identified 13 subpopulations, including a novel subpopulation with inflammation-modulating potential annotated as inflammatory chondrocytes. Fibrocartilage chondrocytes exhibited extensive alteration of gene expression patterns in osteoarthritic cartilage compared with nonosteoarthritic cartilage. Both inflammatory chondrocytes and fibrocartilage chondrocytes showed a trend toward increased numbers in osteoarthritic cartilage. In these two subpopulations from osteoarthritic cartilage, the ferroptosis pathway was enriched, and expression of iron overload-related genes, e.g., FTH1, was elevated. To verify these findings, we conducted a Mendelian randomization study using UK Biobank and a population-based cross-sectional study using data collected from Xiangya Osteoarthritis Study. Genetic predisposition toward higher expression of FTH1 mRNA significantly increased the risk of hand osteoarthritis (odds ratio = 1.07, 95% confidence interval: 1.02-1.11) among participants (n = 332 668) in UK Biobank. High levels of serum ferritin (encoded by FTH1), a biomarker of body iron overload, were significantly associated with a high prevalence of hand osteoarthritis among participants (n = 1 241) of Xiangya Osteoarthritis Study (P-for-trend = 0.037). In conclusion, our findings indicate that inflammatory and fibrocartilage chondrocytes are key subpopulations and that ferroptosis may be a key pathway in hand osteoarthritis, providing new insights into the pathophysiology and potential therapeutic targets of hand osteoarthritis.

Genetically Predicted Levels of Serum Metabolites and Risk of Sarcopenia: A Mendelian Randomization Study

Metabolites' connection to sarcopenia through inflammation and mitochondrial dysfunction is presumed, but their impact remains unclear due to limitations in conventional observational studies caused by confounding bias and reverse causation. We conducted a Mendelian randomization (MR) analysis to elucidate the association of serum metabolites with sarcopenia and its related traits, i.e., appendicular lean mass and grip strength. Genetic instruments to proxy the serum metabolites were extracted from the most comprehensive genome-wide association study on the topic published so far. The corresponding summary statistics for the associations of genetic instruments with outcomes were calculated from the UK Biobank (n = 324,976 participants). The primary analyses were assessed by an inverse-variance weighted (IVW) method. The weighted median and MR-PRESSO methods were used as sensitive analyses. Fourteen genetically predicted serum metabolites were associated with the risk of sarcopenia (PIVW < 0.05). Two metabolites showed the overlapped association with sarcopenia and its related traits, which were isovalerylcarnitine (sarcopenia: odds ratio [OR] = 4.00, 95% confidence interval [CI] = 1.11~14.52, PIVW = 0.034; appendicular lean mass: β = -0.45 kg, 95% CI = -0.81~-0.09, PIVW = 0.015; grip strength: β = -1.51 kg, 95% CI = -2.31~-0.71, PIVW = 2.19 × 10-4) and docosapentaenoate (sarcopenia: OR = 0.16, 95% CI = 0.03~0.83, PIVW = 0.029; appendicular lean mass: β = -0.45 kg, 95% CI = 0.08~0.81, PIVW = 0.016). Twenty-seven metabolites were suggestive associated with appendicular lean mass or grip strength. This MR study provided evidence for the potential effects of metabolites on sarcopenia.

Genetic Variants, Serum 25-Hydroxyvitamin D Levels, and Sarcopenia: A Mendelian Randomization Analysis

Importance

Vitamin D deficiency is commonly associated with sarcopenia; however, the latest International Clinical Practice Guidelines for Sarcopenia do not recommend vitamin D supplementation for sarcopenia owing to a lack of an apparent therapeutic effect on the indices of sarcopenia among participants with replete vitamin D concentration (ie, 25-hydroxyvitamin D [25(OH)D] level >20 ng/mL) from randomized clinical trials. While there is consensus in all vitamin D guidelines that serum levels of 25(OH)D less than 10 ng/mL should be corrected, approximately 30% of the world population's 25(OH)D levels range from 10 to 20 ng/mL, and it remains unclear whether such suboptimal levels can maintain optimal health, including sarcopenia risk.

Objective

To investigate the association of serum 25(OH)D level, especially suboptimal levels, with sarcopenia risk.

Design, Setting, and Participants

This genome-wide genetic association study was performed from August 2022 to February 2023 among the 295 489 unrelated European participants from the UK Biobank (2006-2010). Nonlinear and standard mendelian randomization analyses were used to examine the association of serum 25(OH)D concentration with sarcopenia risk.

Exposures

A weighted genetic risk score using 35 unrelated single-nucleotide variants from the UK Biobank and weights from the SUNLIGHT Consortium was selected as an instrumental variable for serum 25(OH)D concentration.

Main Outcomes and Measures

The primary outcome was sarcopenia, and the secondary outcomes consisted of grip strength, appendicular lean mass index, and gait speed.

Results

The final genetic analyses included 295 489 participants (mean [SD] age, 56.3 [8.1] years; 139 216 female [52.9%]). There was an L-shaped association between genetically predicted serum 25(OH)D concentration and sarcopenia risk. The risk of sarcopenia decreased rapidly as 25(OH)D concentration increased until 20 ng/mL and then leveled off. The odds ratio of sarcopenia for serum 25(OH)D level of 10 vs 20 ng/mL was 1.74 (95% CI, 1.17-2.59). Similar patterns were also observed when the association between serum 25(OH)D concentration and risks of each of the sarcopenia indices were evaluated.

Conclusions and Relevance

In this mendelian randomization genetic association study of adults in the UK Biobank, the findings supported a nonlinear association between suboptimal 25(OH)D levels and sarcopenia risk. Randomized clinical trials among participants with suboptimal 25(OH)D levels are required to verify the potential causality.

Efficacy and Safety of Tramadol for Knee or Hip Osteoarthritis: A Systematic Review and Network Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

To examine efficacy and safety of tramadol for knee or hip osteoarthritis (OA).

METHODS

PubMed, Embase, Cochrane Library, and Web of Science were searched up to May 2020 for randomized controlled trials (RCTs) comparing any of the following interventions: tramadol 100 mg/day, 200 mg/day, and 300 mg/day, and placebo for knee or hip OA. Pain and function were measured at or near 12 weeks for efficacy. Gastrointestinal, cardiovascular, and central nervous system (CNS) adverse events (AEs), and withdrawals were measured for safety. Bayesian network meta-analysis was conducted.

RESULTS

Six RCTs (3,611 participants) were included. Tramadol 100 mg/day (standardized mean difference [SMD] -0.16 [95% confidence interval (95% CI) -0.34, 0.00]), 200 mg/day (SMD -0.21 [95% CI -0.37, -0.06]), and 300 mg/day (SMD -0.30 [95% CI -0.48, -0.14]) were statistically more effective than placebo in pain relief, but only tramadol 300 mg/day was better than placebo in functional improvement (SMD -0.24 [95% CI -0.47, -0.03]). Tramadol 100 mg/day (relative risk [RR] 2.29 [95% credible interval (CrI) 1.22, 4.25]), 200 mg/day (RR 4.35 [95% CrI 2.31, 8.01]), and 300 mg/day (RR 6.02 [95% CrI 3.22, 11.1]) involved a higher risk of gastrointestinal AEs. Similarly, tramadol 100-300 mg/day showed a higher risk of CNS AEs and withdrawals. However, the risk of cardiovascular AEs remained unclear.

CONCLUSION

Only tramadol 300 mg/day showed minimal improvement in pain and function but with increasing AEs compared with placebo. Tramadol may not be sufficiently recommended for knee or hip OA based on the presented evidence, especially in patients with the risk of gastrointestinal and CNS AEs.

[Changes of the World Health Organization 2022 classification (5th edition) of salivary glands tumors]

Pathological diagnosis of salivary gland tumors is one of the most challenging areas in all head and neck surgical pathology. The classification of salivary gland tumors was updated in the 5th edition of the World Health Organization Classification of Head and Neck Tumours, most of which were based on their molecular pathological characteristerics. This new classification features a description of several new entitiesamong benign and malignant neoplasms, salivary gland tumors with updated naming or diagnostic criteria, and lesions deleted from this section, etc.This present review focuses on the updates and changes in the new classification of salivary gland tumors, and provides some reference for head and neck surgeons and pathologists.

Construction and validation of a revised satisfaction index model for the Chinese urban and rural resident-based basic medical insurance scheme

BACKGROUND

Quality is the most important factor in satisfaction. However, the existing satisfaction index model of urban and rural resident-based basic medical insurance scheme (SIM_URRBMI) lacks the segmentation of perceived quality elements, it couldn't provide a reference for quality improvement and satisfaction promotion. This study aims to construct a revised SIM_URRBMI that can accurately and detailly measure perceived quality and provide feasible and scientific suggestions for improving the satisfaction of urban and rural residents' basic medical insurance scheme (URRBMI) in China.

METHODS

Based on the theoretical framework of the American Customer Satisfaction Index, the elements of perceived quality were refined through literature review and expert consultation, and a pool of alternative measurement variables was formed. A three-stage randomized stratified cluster sampling was adopted. The main decision makers of URRBMI in the families of primary school students in 8 primary schools in Changsha were selected. Both the classic test theory and the item response theory were used for measurement variables selection. The reliability and validity of the model were tested by partial least squares (PLS)-related methods.

RESULTS

A total of 1909 respondents who had URRBMI for their children were investigated. The SIM_URRBMI1.0 consists of 11 latent variables and 28 measurement variables with good reliability and validity. Among the three explanatory variables of public satisfaction, perceived quality had the largest total effect (path coefficient) (0.737). The variable with the greatest effect among the five first-order latent variables on perceived quality was the quality of the medical insurance policy (0.472).

CONCLUSIONS

The SIM_URRBMI1.0 consists of 28 measurement variables and 11 latent variables. It is a reliable, valid, and standard satisfaction measurement tool for URRBMI with good prediction ability for public satisfaction. In addition, the model provides an accurate evaluation of the perceived quality, which will greatly help with performance improvement diagnosis. The most critical aspects of satisfaction improvement are optimizing the scope and proportion of reimbursement as well as setting appropriate level of deductible and capitation of URRBMI.

Liver Fibrosis Assessment by Viewing Sinusoidal Capillarization: US Molecular Imaging versus Two-dimensional Shear-Wave Elastography in Rats

Background US elastography is a first-line assessment of liver fibrosis severity; however, its application is limited by its insufficient sensitivity in early-stage fibrosis detection and its measurements are affected by inflammation. Purpose To assess the sensitivity of US molecular imaging (USMI) in early-stage liver fibrosis detection and to determine whether USMI can specifically distinguish fibrosis regardless of inflammation when compared with two-dimensional (2D) shear-wave elastography (SWE). Materials and methods USMI and 2D SWE were performed prospectively (January to June 2021) in 120 male Sprague-Dawley rats with varying degrees of liver fibrosis and acute hepatitis and control rats. Liver sinusoidal capillarization was viewed at CD34-targeted USMI and quantitatively analyzed by the normalized intensity difference (NID). Data were compared by using a two-sided Student t test or one-way analysis of variance. Linear correlation analyses were used to evaluate the relationships between collagen proportionate area values and NID and liver stiffness measurement (LSM) values. Receiver operating characteristic curves were used to assess the diagnostic performance in detecting liver fibrosis. Results Both NID and LSM values showed good linear correlation with collagen proportionate area values (r = 0.91 and 0.87, respectively). No difference was observed between the areas under the receiver operating characteristic curve in detecting stage F0-F1 between USMI and 2D SWE (0.97 vs 0.91, respectively; P = .20). USMI depicted liver fibrosis at an early stage more accurately than 2D SWE (area under the curve, 0.97 vs 0.82, respectively; P = .01). Rats with hepatitis had higher liver stiffness values than control rats (9.83 kPa ± 0.79 vs 6.55 kPa ± 0.38, respectively; P < .001), with no difference in the NID values between control rats and rats with hepatitis (6.75% ± 1.43 vs 6.74% ± 0.86, respectively; P = .98). Conclusion Sinusoidal capillarization viewed at US molecular imaging helped to detect early-stage liver fibrosis more accurately than two-dimensional shear-wave elastography and helped assess fibrosis regardless of inflammation. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Barr in this issue.

Association of Metformin Use With Risk of Venous Thromboembolism in Adults With Type 2 Diabetes: A General-Population-Based Cohort Study

Metformin is hypothesized to protect against the risk of venous thromboembolism (VTE); however, there is a paucity of data supporting this hypothesis. Among individuals aged 40-90 years with a diagnosis of type 2 diabetes in the Health Improvement Network database (2000-2019), we compared the risks of incident VTE, pulmonary embolism, and deep vein thrombosis among metformin initiators with those among sulfonylurea initiators. Individuals were followed from their first prescription refill to an incident VTE, drug discontinuation, switching or augmenting, plan disenrollment, or the end of the study, whichever occurred first. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using the Cox model, adjusting for confounders using inverse probability of treatment weighting. Among 117,472 initiators of metformin and 13,835 initiators of sulfonylureas, 555 (1.3/1,000 person-years) and 75 (2.1/1,000 person-years) VTE cases occurred in each group, respectively. The multivariable-adjusted HR was 0.65 (95% CI: 0.51, 0.84). The corresponding risks for pulmonary embolism (adjusted HR = 0.71, 95% CI: 0.50, 1.01) and deep vein thrombosis (adjusted HR = 0.64, 95% CI: 0.48, 0.87) were also lower in metformin initiators than in sulfonylurea initiators. Our study provided empirical evidence to support a lower risk of VTE after initiation of metformin as compared with sulfonylureas among patients with type 2 diabetes.

Causal Relationship of Genetically Predicted Serum Micronutrients Levels With Sarcopenia: A Mendelian Randomization Study

Objectives

Previous observational studies have suggested associations between concentrations of several circulating micronutrients and sarcopenia. However, the causality inferred from those studies was subjected to residual confounding and reverse causation. Therefore, we aimed to examine the causal effects of the levels of genetically predicted serum micronutrients on sarcopenia.

Methods

Single nucleotide polymorphisms (SNPs) were chosen from large-scale genome-wide association studies of participants only with European descent and were used as genetic instruments for the levels of 10 serum micronutrients (calcium, magnesium, selenium, copper, iron, zinc, Vitamin A, Vitamin B12, Vitamin D, and Vitamin E). Sarcopenia was defined by referencing to the 2019 definition given by the European Working Group on Sarcopenia in Older People (EWGSOP). A two-sample Mendelian randomization (MR) analysis was carried out to examine the associations between the levels of genetically predicted serum micronutrients and the risk of sarcopenia. Then, sensitivity analyses (including weighted median, MR-Egger and leave-one-out sensitivity analyses) were performed to evaluate the robustness of study findings. The estimates were presented as odds ratio (OR) with their 95% confidence intervals (CIs) per one standard deviation (SD) increase in the exposures.

Results

A total of 378,635 UK Biobank participants, including 572 participants who were identified with sarcopenia, were included in this study. The iron status was shown to have a clear effect on the risk of sarcopenia based on MR analyses. The per one SD increment in the genetically-determined serum iron level corresponded to a 53% increase in the risk of sarcopenia (OR = 1.53, 95% CI: 1.31-1.78, P = 0.001). The exclusion of SNPs of the circulating iron level (i.e., rs1799945 SNP, rs1800562 SNP or rs855791 SNP) did not attenuate the magnitude of the signal in MR analysis. There was little evidence supporting the associations between other remaining micronutrients and sarcopenia.

Conclusions

An increased risk of sarcopenia was observed with a genetically higher concentration of iron, suggesting that iron may play a role in the occurrence or development of sarcopenia.

Contrast-enhanced ultrasound of intrahepatic portal vein gas: Case report and review of literature

Portal vein gas is a rare imaging finding and a concomitant sign of abdominal disease. Here, we report a 64-year-old man with an emphasis on contrast-enhanced ultrasound for describing the findings for portal vein gas and evaluating liver blood perfusion. Ultrasonography is a favorable imaging modality for the rapid bedside evaluation and monitoring of portal vein gas in the emergency room.

VEGFR2-targeted ultrasound molecular imaging of angiogenesis to evaluate liver allograft fibrosis

Liver allograft fibrosis (LAF) is a common challenge threatening patient survival after liver transplantation, making a potent imaging technique vital for clinical management. To date, ultrasound (US) elastography has been regarded as one of the most promising techniques for LAF monitoring. However, it is susceptible to inflammation and also insensitive to early-stage pathological changes, which affects its diagnostic accuracy of LAF. Herein, based on a thorough comparison with US elastography at multiple disease stages, VEGF receptor-2 (VEGFR2) targeted US molecular imaging (USMI) was validated to be highly potent for LAF early diagnosis and staging. The VEGFR2-targeted microbubbles (MBs) were fabricated as a specific probe for angiogenesis. Then, VEGFR2-targeted USMI and US elastography were compared in terms of evaluating the LAF progress in a rodent model. The quantitative USMI result displayed a much higher linear correlation with histological standards including the Metavir fibrosis score (R² = 0.77 vs. 0.35) and VEGFR2 semi-quantitative counting (R² = 0.78 vs. 0.49) than US elastography, which demonstrated a greatly improved diagnostic accuracy. The study not only revealed the mechanism of employing angiogenesis to describe LAF but also overcame the intrinsic limitations of US elastography, thus highlighting the potential of VEGFR2-targeted USMI as an effective monitoring tool for LAF surveilling.

The Relationships between Screen Use and Health Indicators among Infants, Toddlers, and Preschoolers: A Meta-Analysis and Systematic Review

Evidence suggests that excessive screen time in early childhood is related to children's physical and mental health. This study aimed to review the relationships between screen media use and several health indicators in infants, toddlers, and preschoolers. A systematic search was conducted by two independent reviewers on PubMed, Web of Science, Embase, and Cochrane Library to identify the eligible studies, with an end date of 13 August 2019. Included studies (published in English) were peer-reviewed and met the determinate population (children aged 0-7 years with screen media exposure and related health outcomes). The AHRQ, NOS, and the Cochrane Handbook were used to evaluate the cross-sectional study, cohort study, and RCT, respectively. A meta-analysis and narrative syntheses were employed separately. Eighty studies (23 studies for meta-analysis) met the inclusion criteria for the systematic review. Strong evidence of the meta-analysis suggested that excessive screen time was associated with overweight/obesity and shorter sleep duration among toddlers and preschoolers. Excessive screen use was associated with various health indicators in physical, behavioral, and psychosocial aspects. Better-quality research on newer media devices, on various kinds of contents in young children, and on dose-response relationships between excessive screen use and health indicators are needed to update recommendations of screen use.

Changes in the Intestinal Microbiota in Patients with Stage 5 Chronic Kidney Disease on a Low-Protein Diet and the Effects of Human to Rat Fecal Microbiota Transplantation

Background

Dietary protein restriction is recommended for patients with stage 5 chronic kidney disease (CKD), or end-stage renal disease (ESRD). This study aimed to investigate the changes in the intestinal microbiota due to different dietary regimens in patients with stage 5 CKD and the effects of human to rat fecal microbiota transplantation.

Material/Methods

Second-generation high-throughput sequencing was used to analyze the amplifiers in the 16S rRNA V4 region in the intestinal microbiota of patients with stage 5 CKD and healthy individuals. The intestinal microbiota of patients with stage 5 CKD in the low-protein group and the healthy individual group was transferred by human to rat fecal microbiota transplantation using Sprague-Dawley rats. Data underwent meta-analysis using Meta-Stat.

Results

Patients with CKD on a very low-protein diet showed an increase in intestinal Escherichia, Shigella, and Klebsiella, a decrease in Blautia, heat map analysis showed that Christensenellaceae R-7 group rs1 were significantly increased, and MetaStat analysis showed that Bacteroides, Prevotella, and Mitsuokella were significantly increased. Following human to rat fecal microbiota transplantation from patients with stage 5 CKD, the profile of the rat intestinal microbiota became similar to the human donors. The weight of the rats fed a very low-protein diet after fecal microbiota transplantation significantly decreased after six weeks compared with normal rats and rats that received normal fecal microbiota transplantation.

Conclusions

Patients with stage 5 CKD on a very low-protein diet showed changes in the intestinal microbiota that could be transferred from humans to rats by fecal microbiota transplantation.

Effect of feeding patterns on growth and nutritional status of children aged 0-24 months: A Chinese cohort study

Objective

This study was aimed to examine the effect of feeding patterns on growth and nutritional status of children aged 0~24 months.

Methods

We conducted a cohort study with an initial sample of 927 children. Considering the follow-up losses, 903, 897, 895, 897, 883, 827 and 750 children were followed up at 1, 3, 6, 8, 12, 18 and 24 months, respectively. Children were grouped according to exclusive breastfeeding (EBF) duration in the first 6 months: (1) never EBF; (2) EBF ≤ 3 months: EBF ≤ 3 months and stopped BF after 3 months or EBF ≤ 3 months and BF = 6 months or EBF ≤ 3 months and BF after 3 months, had formula and/or solids; (3) EBF for 3 ~ 6 months: BF < 3 months and EBF for 3 ~ 6 months or EBF for 3 ~ 6 months and BF < 3 months, had formula and/or solids; (4) EBF = 6 months. We used Z-scores to evaluate the growth and nutritional status of children, used the generalized estimation equation to compare the difference between feeding patterns.

Results

The generalized estimation equation results showed that Weight-for-age Z-score (WAZ), Length-for-age Z-score (LAZ), and Weight-for-length Z-score (WLZ) in different feeding patterns had statistical significance. The WAZ in EBF for 6 months group was higher in the first 8 months, in never EBF group was higher after 12 months old; the LAZ in EBF for 6 month group was lower than other groups; the WLZ in EBF for 6 months group was higher than EBF for 3 ~ 6 months group. The EBF ≤ 3 months group had higher underweight, stunting, and wasting rates. The EBF for 6 months had a higher stunting rate; the never EBF and EBF for 6 months groups had higher overweight and obesity rates.

Conclusions

In conclusion, different feeding patterns affect growth and nutritional status in children, so proper guidelines should be implemented to improve nutritional status and promote the growth of children.

The Associations between the Duration of Folic Acid Supplementation, Gestational Diabetes Mellitus, and Adverse Birth Outcomes based on a Birth Cohort

This study aimed to examine the associations between the duration of folic acid (FA) supplementation, gestational diabetes mellitus (GDM), and adverse birth outcomes. A total of 950 mother-offspring pairs participated in the cohort study during 2015 in Changsha, China. The data were collected through home visits and perfected by maternal and child healthcare handbooks. Generalized linear models and stratified analyses were used for statistical analyses. The incidence of GDM in our cohort was 10.2%. FA supplementation for ≥3 months before pregnancy was associated with an increased risk of GDM (adjusted relative risk (aRR): 1.72; 95% CI: 1.17–2.53) and decreased risk of small-for-gestational-age (SGA) birth (aRR: 0.40; 95% CI: 0.18–0.88). In the group of FA supplementation for ≥3 months during pregnancy, GDM was associated with an increased risk of cesarean delivery (aRR: 1.36; 95% CI: 1.06–1.75) and macrosomia (aRR: 2.11; 95% CI: 1.06, 4.20), but the aRRs were lower than the RR_MH 1.53 (95% CI: 1.01–2.34) and 2.43 (95% CI: 1.27–4.66). Our study suggested that the longer duration of FA supplementation before pregnancy might increase the risk of GDM, but decrease the risk of SGA birth. Longer duration of FA supplementation during pregnancy had beneficial effects on birth outcomes in women with GDM. Further studies should consider a larger sample size to confirm these findings.

Patterns of Women's Postpartum Weight Retention and Its Associations with Maternal Obesity-Related Factors and Parity

Background: There is not much data on the effects of the timing of gestational weight gain (GWG), pre-pregnancy waist circumference (WC), pre-pregnancy body mass index (BMI), and parity, with postpartum weight retention (PPWR) trajectories. Methods: This study was based on a longitudinal cohort. Latent growth mixture models were applied to identify the latent trajectories of PPWR and test the effects of the predictors on distinct classes of PPWR trajectories. Results: Three PPWR trajectories were identified. About 2.8% (n = 26) of women were classified into Class 1, with an inverted U-shape trajectory; 6.6% (n = 61) were assigned to Class 2, with a rapid increase trajectory; 90.6% (n = 837) were classified into Class 3, with a significant decrease. Women who had a lower pre-pregnancy BMI (β = −0.279), higher pre-pregnancy WC (β = 0.111) and GWG (β = 0.723) were at a higher risk of retaining more weight at 1 month postpartum. Only GWG, especially GWG during late pregnancy, was associated with the rate of PPWR change. Parity was not associated with the changes in PPWR, while, compared to Class 1 trajectory, multiparous women were protected from having a Class 2 trajectory. Conclusions: Early targeted interventions should be taken to prevent women who were primiparous, and/or had a lower pre-pregnancy BMI and higher pre-pregnancy WC and GWG, from excessive PPWR.

Association of Assisted Reproductive Techniques with Infant Feeding Practices: A Community-Based Study in China

Background: With births generated with assisted reproductive techniques (ARTs) increasingly, the effect of ARTs on infant feeding behaviors is an essential topic to explore. However, limited literature focused on this topic. The objective of this study is to examine the effect of ARTs on infant feeding behaviors. Materials and Methods: Participants, including 41 mothers who conceived with ARTs and 935 conceived spontaneously, were drawn from a prospective birth cohort between January 2015 and December 2015. The participants were followed up at 1, 3, 6, 8, and 12 months postpartum at their residences through a face-to-face interview. Feeding behaviors, including breastfeeding initiation, partial/exclusive breastfeeding duration and formula introduction were assessed using World Health Organization-recommended definitions. Cox and logistic regression models were applied to examine the association of assisted conception with feeding behaviors. Results: Breastfeeding initiation rates were comparable between women who conceived with and without ARTs (70.7% versus 76.0%). Breastfeeding duration and formula introduction were significantly shorter and earlier in assisted conceptions in univariate analyses at 6 months postpartum [crude hazard ratios (HRs), 95% confidence intervals (CIs) 2.02 (1.03-3.84), and 1.63 (1.09-2.44)]. However, after controlling for covariates, assisted conception was only associated with shorter breastfeeding duration at 6 months postpartum [adjusted HR 1.99, 95% CI 1.05-3.80], no significant differences were found in infant feeding outcomes at 12 months postpartum among women with ART conception versus general conception. Mothers who conceived through ARTs with cesarean deliveries were at the highest risks of shorter breastfeeding duration and earlier formula introduction than mothers who conceived spontaneously with vaginal deliveries. Conclusions: Mothers who conceive through ARTs are associated with shorter breastfeeding durations for the first 6 months, compare to mothers who conceive spontaneously. Furthermore, cesarean delivery has a joint effect with the treatment of ARTs on promoting the development of poor feeding behaviors.

A prospective study of maternal postnatal depressive symptoms with infant-feeding practices in a Chinese birth cohort

BACKGROUND

The first few weeks after childbirth are critical, as women may encounter lactation problems and postpartum depression during this period. However, it is still unclear whether early breastfeeding behaviours are related to the symptoms of postnatal depression (PND) in Chinese populations. Therefore, the current study aimed to investigate the association between symptoms of PND and infant feeding practices based on a large-scale Chinese cohort.

METHODS

A prospective study of the community-based cohort was conducted from January 2015 to December 2016. Infant feeding outcomes, including exclusive/partial breastfeeding and formula feeding, were assessed according to the WHO guidelines. Symptoms of PND were assessed by the Edinburgh Postnatal Depression Scale at 4 weeks postpartum. Multivariate generalized estimating equation models were applied to investigate the associations between depressive symptoms and infant feeding behaviours.

RESULTS

A total of 956 mother-infant pairs were included. Fifty-six mothers presented screen-positive symptoms of PND with a cut-off ≥10. The percentage of early breastfeeding initiation was 75.8%, while the average duration of exclusive breastfeeding was 3.90 ± 2.33 months. Postnatal depressive symptoms were associated with a shorter breastfeeding duration (8.02 vs. 6.32 months, P < 0.05) and earlier formula introduction (4.98 vs. 3.60 months, P < 0.05). After adjustments were made for covariates, postnatal depressive symptoms were associated with an increased risk of the discontinuation of exclusive and partial breastfeeding (β = - 0.049, P = 0.047 and β = - 0.082, P = 0.006, respectively). Compared to mothers without symptoms of PND, mothers with depressive symptoms were more likely to supplement formula for their infants in the first year of life (β =0.074, P = 0.016). These associations were still significant in the sensitivity analyses, using an EPDS cut-off of ≥13.

CONCLUSIONS

Our findings indicate that depressive symptoms at 4 weeks postpartum are associated with the cessation of exclusive and partial breastfeeding duration and the introduction of formula in the 12 months of delivery. Early psychosocial assessment and social support should be offered to mothers in the early postpartum period to indirectly prevent adverse breastfeeding outcomes.

Prospective association between sleep-related factors and the trajectories of cognitive performance in the elderly Chinese population across a 5-year period cohort study

The integral role of sleep in cognition, such as night-time sleep and napping duration, has yielded mixed findings, especially in healthy elderly adults. This study aimed to identify the heterogeneous classes of the cognitive trajectories and investigated the associations between sleep parameters and the trajectories of cognition in different elderly subpopulations. The study was based on a large, national representative sample aged 60 years or older. Two cognitive measures were assessed, including executive function and episodic memory. Sleep parameters were evaluated, including post-lunch napping, night-time sleep duration, and sleep disturbances. Latent growth mixture model (LGMM) was used to describe the trajectories of cognition and investigate the effects of sleep factors on cognition. Three heterogeneous trajectories were identified for executive cognition and four for episodic memory. Inverted U-shape associations of cognition with night-time sleep and napping duration were found. In LGMM, night-time sleep duration was negatively associated with the baseline episodic memory in elderly adults. Post-lunch napping was positively associated with the baseline executive function (β = 0.078, P<0.05) and episodic memory (β = 0.084, P<0.05) in men, whereas it was only associated with impaired episodic memory (β = -0.152, P<0.05) in women. Frequent sleep disturbances were only associated with the impaired executive function at baseline (β = -0.088, 95%CI -0.162, -0.013) among older men. Overall, sleep parameters played different roles in heterogeneous trajectories of cognition by sex difference. Sleep factors may not be related to the rate of cognition decline, but these factors, independent of time-variant depressive symptoms, were associated with the initial status of cognition at baseline.

Effects of Maternal Prenatal Multi-Micronutrient Supplementation on Growth and Development until 3 Years of Age

At present, there is insufficient evidence on whether prenatal multi-micronutrient (MM) supplementation can be an antenatal nutritional intervention or not. This study aimed to explore the sustained effect of prenatal MM supplementation on early childhood health. A total of 939 mother–offspring pairs were followed up in the study between 2015 to 2018 in Changsha, China. Information was mainly collected through household surveys at the ages of 1, 3, 6, 8, 12, 18, 24, and 36 months. General linear models and generalized estimating equation models were used to estimate the effects of maternal prenatal MM compared with IFA supplementation on infant growth and development. Offspring of women who used prenatal MM compared with IFA supplements had lower weight-for-age z score (WAZ) (adjusted β: −0.23, 95% CI: (−0.40, −0.06)) and weight-for-length z score (WLZ) (adjusted β: −0.20, 95% CI: (−0.37, −0.02)) at 3 months old, but a reduced risk of obesity at birth (aRR: 0.30, 95% CI: 0.11–0.78) and being overweight at 3 months old (aRR: 0.52, 95% CI: 0.32–0.84). Moreover, offspring of women who used prenatal MM compared with IFA supplements had significantly higher scores for communication (adjusted β: 0.41, 95% CI: 0.61–0.21), gross motor (adjusted β: 0.68, 95% CI: 0.49–0.88), fine motor (adjusted β: 1.64, 95% CI: 1.45–1.84), problem solving (adjusted β: 0.29, 95% CI: 0.10–0.49), and personal–social (adjusted β: 0.90, 95% CI: 0.70–1.10) skills at 36 months old. Prenatal MM supplementation could result in better infant growth in the first few months of life and improve development scores at the age of 3 years compared with IFA supplementation.

Influence of prenatal and early-life exposures on food allergy and eczema in infancy: a birth cohort study

Background

Few prospective birth cohort studies are available on the effects of prenatal and early-life exposures on food allergy and eczema among Chinese children. The aim of this study was to evaluate the influence of prenatal and early-life exposures on food allergy and eczema during the first year of life in a prospective birth cohort study.

Methods

This study was based on a prospective, observational birth cohort of 976 mother-child pairs in three Streets in Changsha, China from January to December 2015. Data on prenatal, early-life exposures and allergic outcomes were obtained from questionnaires collected at birth, and 1, 3, 6, 8, and 12 months of age. Multivariate logistic regression models were performed to estimate the effects of prenatal and early-life exposures on food allergy and eczema.

Results

Common risk factors for food allergy and eczema in infancy were parental history of allergy, while moderate eggs consumption (3–4 times/week) during pregnancy was protective for both of them compared with low consumption (≤ 2 times/week). Factors only associated with food allergy were maternal aquatic products consumption during pregnancy, number of older siblings and age of solid food introduction, whereas factors only associated with eczema were maternal milk or milk products consumption during pregnancy, maternal antibiotic exposure during pregnancy, season of birth and antibiotic exposure through medication during the first year of life.

Conclusion

Our study suggests that factors associated with food allergy and eczema are multifaceted, which involving hereditary, environmental and nutritional exposures. Furthermore, differential factors influence the development of food allergy and eczema in infants.

A meta-analysis of pregnancy-related outcomes and complications in women with polycystic ovary syndrome undergoing IVF

This meta-analysis aimed to study whether pregnancy-related outcomes and complications differed between patients with polycystic ovary syndrome (PCOS) and those with other causes of infertility who had undergone IVF. A systematic search of PubMed, Embase, the Cochrane Library and Chinese databases was carried out to identify relevant studies published before July 2018. Outcomes were expressed as odds ratios (OR) and 95% confidence intervals (CI). Subgroup analyses and sensitivity analyses were also conducted. Twenty-nine studies were identified for inclusion. Women with PCOS had higher risks of miscarriage (OR 1.41, 95% CI 1.04-1.91), ovarian hyperstimulation syndrome (OR 4.96, 95% CI 3.73-6.60), gestational diabetes mellitus (OR 2.67, 95% CI 1.43-4.98), pregnancy-induced hypertension (OR 2.06, 95% CI 1.45-2.91), preterm birth (OR 1.60, 95% CI 1.25-2.04) and large-for-gestational-age babies (OR 2.10, 95% CI 1.01-4.37). Women with PCOS showed similar rates of clinical pregnancy, multiple pregnancy, ectopic pregnancy, small for gestational age and congenital malformations, and a higher live birth rate, compared with women without PCOS. This study provides an update on and comprehensive evidence to support the observation that despite the fact that PCOS patients achieve a better live birth rate, physicians should continue to consider them to be at high risk of adverse pregnancy-related outcomes.

Associations of Pre-Pregnancy BMI, Gestational Weight Gain and Maternal Parity with the Trajectory of Weight in Early Childhood: A Prospective Cohort Study

Background: The association of maternal parity, pre-pregnancy body mass index (BMI) and gestational weight gain (GWG) with childhood weight status has been well studied; however, little is known about these factors with respect to the rate of weight changes in early childhood. Methods: This study was based on a prospective longitudinal study. The follow-up surveys were conducted at the ages of 1, 3, 6, 8, 12, and 18 months. Child weight was investigated twice at each wave. Data on maternal parity, pre-pregnancy weight and height were collected at baseline. The latent growth curve model was used to examine the effects of interested predictors on the trajectory of weight in early childhood. Results: Finally, 893 eligible mother-child pairs were drawn from the cohort. In adjusted models, multiparas were associated with higher birth weight (β = 0.103) and slower weight change rate of children (β = −0.028). Pre-conception BMI (β = 0.034) and GWG (β = 0.014) played important roles in the initial status of child weight but did not have effects on the rate of weight changes of the child. Conclusions: Multiparous pregnancy is associated with both higher mean birth weight and slower weight-growth velocity in early childhood, while pregravid maternal BMI and GWG are only related to the birth weight.

Modifiable Individual Factors Associated with Breastfeeding: A Cohort Study in China

Breast milk is an ideal first food for infants in the initial months of life. This study aimed to identify modifiable individual factors in breastfeeding during the first six months of life in Hunan. This birth cohort study was conducted in three communities in Changsha, Hunan province. Data were collected through maternal health manuals and self-administered questionnaires during the follow-up period. To find risk factors and calculate odds ratios, generalized estimating equation models were applied. The final study included 951 mother-infant pairs. The prevalence of exclusive breastfeeding and any breastfeeding in this study was below the World Health Organization's breastfeeding goals. Infant age, passive smoking after delivery, minor postnatal depression, and feeding-bottles were shown to act negatively on both exclusive breastfeeding and any breastfeeding. In addition, cesarean delivery and delayed breastfeeding initiation had adverse effects on exclusive breastfeeding. Multiparas were less likely to continue any breastfeeding during the first few months. This study highlights the importance of screening probable maternal depression during primary care service and reducing secondhand smoke and feeding-bottle use. The results also suggest that healthcare professionals should provide more assistance and education to multiparas and mothers with cesarean delivery or delayed breastfeeding initiation.

[Factors associated with postpartum weight retention based on the generalized estimation equation in Kaifu Districtin Changsha]

OBJECTIVE

To investigate the current status of the postpartum weight retention (PPWR) in Kaifu District of Changsha, and explore the influential factors with PPWR based on the generalized estimating equation model.
 Methods: A cluster sampling method was applied to select women who gave birth at the health service centers of 3 street communities in Kaifu District of Changsha during 2015. According to the inclusion and exclusion criteria, 783 cases were finally included in the study. Data on PPWR were collected prospectively by using the self-made questionnaire at 1, 3, 6 and 8 months after childbirth. Analysis were performed to investigate the associations between PPWR and its potential factors with generalized estimation equation model.
 Results: The mean PPWR of women was gradually decreased with the increase of postpartum time, and 34.6% of them have returned to the pre-pregnancy weight in the 8 months postpartum. Our findings revealed that gestation weight gain (GWG), pre-pregnancy body mass index, feeding patterns, and delivery mode were significantly associated with maternal PPWR (P<0.05). In contrast, maternal age, educational level, per capita income of family, parity and postpartum depression were not contributed to PPWR (P>0.05).
 Conclusion: GWG is one of the most important predictors for PPWR. The key to reducing PPWR is to control GWG systematically. Early targeted interventions and health education should be taken to prevent women from excessive PPWR at the first-year postpartum, in particular to the women who underwent cesarean deliveries and breastfed their infants. It is conducive to reduce the risks of overweight or obesity caused by PPWR.

Associations of childhood socioeconomic status with mid-life and late-life cognition in Chinese middle-aged and older population based on a 5-year period cohort study

OBJECTIVES

A prospective study was performed to examine the relationship of childhood socioeconomic status (SES) with cognition and the rate of change in a nationally representative sample of community-dwelling middle-aged and older Chinese population.

METHODS

This study mainly focused on 3 composite measures of cognitive function, including Telephone Interview of Cognitive Status, word recall, and drawing a figure successfully. Childhood SES was evaluated by parental occupation and education, childhood residence, and self-evaluated financial status. We designed an analysis strategy adding predictors incrementally in different models to examine the changes of effects of childhood SES on cognition by latent growth curve models.

RESULTS

Finally, a total of 10 533 respondents were prospectively studied, including 5980 respondents aged 45-59 and 4553 aged 60-90. Cognition in younger cohort showed a curvilinear change, while cognition in older cohort showed a linear decline. After controlling for covariates, middle-aged respondents with higher self-evaluated financial status (β: -0.22, P < .001), better health status (β: -0.13, P < .001), higher parental education (β: 0.17 and 0.10, P < .001), who had lived in city/town before 16 years (β: 0.69, P < .001), and whose fathers engaged in nonfarming work (β: 0.43, P < .001) were associated with the better baseline cognition. Similar results were found in older cohort. Additionally, early-life SES was not associated with cognitive decline in both cohorts.

CONCLUSIONS

This study indicates that childhood SES is associated with mid-life and late-life baseline cognition, but it is not contributed to cognition decline. Interventions in early-life focused on improving childhood SES might have positive impacts on baseline cognition in later-life.

Influences of Cesarean Delivery on Breastfeeding Practices and Duration: A Prospective Cohort Study

BACKGROUND

Mothers are encouraged to exclusively breastfeed for the first 6 months. However, cesarean delivery rates have increased worldwide, which may affect breastfeeding. Research aim: This study aimed to determine the potential effects of cesarean delivery on breastfeeding practices and breastfeeding duration.

METHODS

This was a 6-month cohort study extracted from a 24-month prospective cohort study of mother-infant pairs in three communities in Hunan, China. Data about participants' characteristics, delivery methods, breastfeeding initiation, use of formula in the hospital, exclusive breastfeeding, and any breastfeeding were collected at 1, 3, and 6 months following each infant's birth. The chi-square test, logistic regression model, and Cox proportional hazard regression model were used to examine the relationship between breastfeeding practices and cesarean delivery.

RESULTS

The number of women who had a cesarean delivery was 387 (40.6%), and 567 (59.4%) women had a vaginal delivery. The exclusive breastfeeding rates at 1, 3, and 6 months were 80.2%, 67.4%, and 21.5%, respectively. Women who had a cesarean delivery showed a lower rate of exclusive breastfeeding and any breastfeeding than those who had a vaginal delivery ( p < .05). In addition, cesarean delivery was related with using formula in the hospital and delayed breastfeeding initiation. Cesarean delivery also shortened the breastfeeding duration (hazard ratio = 1.40, 95% confidence interval [1.06, 1.84]).

CONCLUSION

Healthcare professionals should provide more breastfeeding skills to women who have a cesarean delivery and warn mothers about the dangers of elective cesarean section for breastfeeding practices.

[Risk factors for delayed breastfeeding initiation based on decision tree model and logistic regression model]

OBJECTIVE

To determine influential factors for delayed breastfeeding initiation.
 Methods: Using questionnaires to collect the data of 950 pregnant women and infants' feeding practices in Changsha, Hunan, logistic regression and decision tree model were used to determine influential factors for delayed breastfeeding initiation.
 Results: Mothers with timely breastfeeding initiation were 594 (62.5%), and those with delayed breastfeeding initiation accounted for 356 (37.5%). Mothers with timely breastfeeding initiation were more likely to use exclusive breastfeeding than those with delayed breastfeeding initiation (P<0.05). Four risk factors were found by logistic regression model and decision tree model, including cesarean delivery, using feeding-bottle before breastfeeding initiation, falling ill, and vomiting during pregnancy. Receiver operating characteristic curve showed no significant difference in the predictive effect of the 2 models (Z=0.142, P=0.889).
 Conclusion: Cesarean delivery, using feeding-bottle before initiation of breastfeeding, and poor physical condition during pregnancy exert negatively effects on breastfeeding initiation. Health workers should help mother to timely initiate breastfeeding and enhance their confidence in exclusive breastfeeding.

Prospective associations between pulse pressure and cognitive performance in Chinese middle-aged and older population across a 5-year study period

Background

Substantial evidence indicates that the relationship between blood pressure (BP) measures and cognitive functioning is inconsistent, complex, and age-related. Pulse pressure (PP), which can not only reflect arterial stiffness and but also represent the chronic effects of hypertension other than BP itself, has been considered as a better predictor of cognitive impairment. However, evidence on the association of cognitive function with PP has not been investigated extensively. We examined this relationship in a longitudinal study based on the latent growth model (LGM).

Methods

This study was based on a nationally representative sample of Chinese middle-aged and older participants from the China Health and Retirement Longitudinal Study (CHARLS), a prospective observational study conducted from 2011 to 2016. Cognitive performance was assessed on the basis of three measures of cognition. The PP was calculated as the difference of the average values of three systolic and diastolic BP readings. A series of potential confounders were collected in this research. The LGM was used to examine the effects of PP on cognitive performance at three time points. To test the independent effects of PP on the initial level and the subsequent development of cognition, unconditional and conditional models were compared sequentially.

Results

After excluding respondents with missing key variables, we ultimately included 9750 participants in the analysis. Cognitive performance scores and PP showed significant differences across time. After adjustment for the confounders, the standardized coefficients of PP in the LGM indicated negative effects on cognitive performance in elderly Chinese participants at wave 2 and wave 3 (P < 0.01). The initial level of PP in the unconditional model was negatively associated with the initial level (β = − 0.25) and the slope (β = − 0.16) of cognition, whereas these effects were attenuated and the association between intercept of PP and slope of cognition became nonsignificant after controlling for the confounders.

Conclusions

The implications of these results demonstrate that a higher PP lowers the cognitive performance of middle-aged and elderly persons independent of a comprehensive set of covariates, but it is not a contributor to the rate of change in cognition.

Electronic supplementary material

The online version of this article (10.1186/s13195-018-0355-1) contains supplementary material, which is available to authorized users.

[Influential factors for postpartum depression based on the structural equation model in Kaifu District in Changsha]

OBJECTIVE

To investigate the current status of the postpartum depression in Kaifu District in Changsha, and to explore the influential factors for postpartum depression.
 Methods: We selected the mothers, who had a delivery and met the inclusion criteria in Changsha during 2015, as the participants and established a prospective birth cohort study. The social demographic characteristics and health-related information for the mothers and their families were collected by using self-made questionnaire. The mothers' depression symptoms after one month postpartum were assessed by the Edinburgh Postnatal Depression Scale. We used the structural equation model to analyze the influential factors for postpartum depression.
 Results: A total of 961 cases were investigated. 82 of them whose scores of EPDS were≥9 points, and the incidence of PPD was 8.2%. The results of structural equation model revealed the influential factors and their correlations with postpartum depression. It has been shown that maternal age, maternal education level, per capita income of family, intention of pregnancy, pregnancy-related complications, mode of conception, mode of delivery, feeding patterns, birth weight, baby gender, and infant illness could exert effects on postpartum depression.
 Conclusion: The incidence of postpartum depression in Kaifu District is at a low level and the structural equation model can be applied to analyze the influential factors and their relations with postpartum depression.

The mutual effect of pre-pregnancy body mass index, waist circumference and gestational weight gain on obesity-related adverse pregnancy outcomes: A birth cohort study

OBJECTIVE

The aim of this study was to examine the mutual effect of pre-pregnancy body mass index (BMI), waist circumference (WC) and gestational weight gain (GWG) on obesity-related adverse pregnancy outcomes.

METHODS

This birth cohort study was conducted in three Streets in Changsha, China, including a total of 976 mother-child pairs. All data was collected within 15 days after deliveries from a self-administered questionnaire, maternal health manual and perinatal health care information system. Multivariate logistic regression models were conducted to estimate the effects of maternal pre-pregnancy BMI, WC and GWG on obesity-related adverse pregnancy outcomes including gestational diabetes mellitus (GDM), primary cesarean section (P-CS), large for gestational age (LGA) and composite outcome (one or more adverse pregnancy outcomes).

RESULTS

After controlling for all confounders, both maternal pre-pregnancy overweight/obesity and central adiposity contributed to increased risks of GDM [ORs 95% CIs = 2.19 (1.02-4.76) and 2.26 (1.11-4.60), respectively], P-CS [ORs 95% CIs = 1.66 (1.05-2.65) and 1.71 (1.11-2.63), respectively], LGA [ORs 95% CIs = 1.93 (1.07-3.50) and 2.14 (1.21-3.75), respectively] and composite outcome [ORs 95% CIs = 1.82 (1.15-2.87) and 1.98 (1.30-3.01), respectively] compared with mothers with normal pre-pregnancy weight and normal WC. Excessive GWG was found to be associated with an increased risk of LGA [OR 95% CI = 1.74 (1.05-2.89)], but was not significantly related to higher risks of GDM, P-CS and composite outcome [ORs 95% CIs = 0.90 (0.47-1.72), 1.08 (0.77-1.52), and 1.30 (0.94-1.79), respectively]. In terms of the joint effect of maternal pregestational BMI and WC on obesity-related composite outcome, mothers with both pre-pregnancy overweight and central adiposity had the highest risk of composite outcome [OR 95% CI = 3.96 (2.40-6.54)], compared with mothers without pre-pregnancy overweight or central adiposity.

CONCLUSIONS

The results of this study suggest that maternal pre-pregnancy overweight/obesity and central adiposity may contribute to multiple obesity-related adverse pregnancy outcomes, excessive weight gain during pregnancy is associated with an increased risk of LGA. Healthcare providers should carry out health education, and guide women to keep an ideal BMI and WC prior to pregnancy and help them gain optimal weight during pregnancy based on their pre-pregnancy BMI and WC.

Risk factors for postpartum depression among Chinese women: path model analysis

Background

Postpartum depression causes harm to both mothers and infants. The purpose of this study was to find out several potential risk factors, and to identify the intrinsic interrelationships between factors and postpartum depression by constructing a path model. The results of this study may help to control the increasing incidence of maternal postpartum depression.

Methods

The study was based on a sample of mothers from a cross-sectional study which was set up at 4 weeks after a mother had childbirth and was conducted in three streets at Kaifu District of Changsha in Hunan province from January to December 2015. Questionnaires were distributed to subjects who responded to questions concerning factors related to pregnancy, delivery and infants within 4 weeks after childbirth. The Edinburgh Postnatal Depression Scale (EPDS) was used to measure postpartum depression. Chi-square test was used to detect significant differences between non-postpartum depression group and postpartum depression group. A path model was constructed to explore the interrelationships between variables, and to verify the relationships between variables and postpartum depression.

Results

The proportion of maternal postpartum depression was 6.7%. Univariate analysis showed that there were significant differences between non-postpartum depression group and postpartum depression group (all P-values <0.05) on the part of maternal age, parity, frequent exposure to mobile phone during pregnancy, gestational hypertensive disorders, fetus number, premature delivery, birth weight, initiation of breastfeeding, mode of feeding, infant illness within 4 weeks after delivery and infant weight at 4 weeks. Path analysis results showed that the final model could be fitted well with sample data (P = 0.687, CMIN/DF = 0.824, NFI = 0.992, RFI = 0.982, IFI = 1.002, TLI =1.004, CFI = 1.000 and RMSEA < 0.001). Frequent exposure to mobile phone during pregnancy, maternal age and gestational hypertensive disorders had both direct and indirect effects on postpartum depression. Mode of feeding and infant weight at 4 weeks, which was the most total effect on postpartum depression, had only a direct impact on postpartum depression. Fetus number, premature delivery, initiation of breastfeeding and birth weight had only an indirect influence on postpartum depression.

Conclusion

The findings of this study suggest that constructing a path analysis model could identify potential factors and explore the potential interrelations between factors and postpartum depression. It is an effective way to prevent maternal postpartum depression by taking appropriate intervention measures and carrying out health education for pregnant women.

Electronic supplementary material

The online version of this article (doi:10.1186/s12884-017-1320-x) contains supplementary material, which is available to authorized users.

Association between Sleep and Body Weight: A Panel Data Model Based on a Retrospective Longitudinal Cohort of Chinese Infants

The focus of this article is on sleep duration and sleep problems in infants and their association with body weight. A retrospective birth cohort of 519 infants was enrolled in a community-based study conducted in Changsha, China. Infant weight and other health-related information were collected during regular standard checkups at the Community Health Service Centers when infants were 1, 3, 6, 8, and 12 months old. The sleep duration and sleep problems of infants were assessed by maternal self-reports. Panel data model was used to evaluate the association of sleep duration and sleep problems with infant body weight. Significant relevance between self-reported sleep duration and weight of infants has been reported in the literature tested by the fixed effects model (p < 0.01). However, this study indicated that sleep problems of infants had no effect on their weight (p = 0.151), after adjusting feeding patterns and socioeconomic factors of their families. This paper argues that, as a potentially modifiable risk factor, infant sleep duration deserves more attention from their parents and families in order to prevent and control overweight or obesity in infants as well as reducing the incidence of obesity in adults.

[Influential factors of iron deficient anemia among infants aged 8 months based on a case-control study]

OBJECTIVE

To study the status and influential factors of iron deficient anemia (IDA) among infants aged 8 months in Changsha City.
 Methods: A case-control study was performed in this research. The case group including 105 8-month-old infants definitely diagnosed as IDA based on standardized blood test. Four-times numbers of age- and genger-matched infants without IDA were selected as a control group. Chi-square test and conditional logistic regression was used to analyze the influential factors for IDA.
 Results: The incidence rate of IDA among infants aged 8 months in Changsha City was 14.7%. The risk factors were as follows: mother with anemia in late pregnancy (OR=3.540, 95% CI 1.898 to 6.601), mixed feeding within 6 months old (OR=1.682, 95% CI 1.099 to 2.574), artificial feeding within 6 months old (OR=4.162, 95% CI 1.343 to 12.896), complementary feeding before 6 months old (OR=1.423, 95% CI 1.022 to 1.982), complementary feeding at or after 7 months old (OR=4.415, 95% CI 2.150 to 9.064), recurrent respiratory tract infections within 8 months old (OR=2.878, 95% CI 1.224 to 6.764), and repeated diarrhea within 8 months old (OR=3.710, 95% CI 1.533 to 8.980).
 Conclusion: There is certain incidence rate of IDA among infants aged 8 months in Changsha City. To prevent the IDA among infants, we should treat mothers' anemia during pregnancy, advocate scientific feeding, encourage complete breastfeeding until 6 months old, add complementary food timely and reasonably, treat infants suffering from respiratory or digestive diseases actively.

[Risk factors for nausea and vomiting in pregnant women in Changsha]

OBJECTIVE

To explore the risk factors for nausea and vomiting in pregnant women.
 Methods: Using cluster random sampling method and following the exclusion and inclusion criteria, a total of 713 pregnant women from the health service center of 3 street communities in Changsha city district were enrolled. Statistical analysis was used to analyze the relevant influential factors for nausea and vomiting.
 Results: Vomiting incidence in pregnant women was 59.6%. The risk factors for nausea and vomiting were female fetus (OR=1.404, 95% CI 1.035 to 1.905), vaginal bleeding (OR=1.513, 95%CI 1.062 to 2.156) and life stress (OR=1.031, 95% CI 1.009 to 1.054), and the protective factor for nausea and vomiting was the age (OR=0.798, 95% CI 0.661 to 0.964).
 Conclusion: The pregnant vomiting is a result of a combination of multiple factors. Age, female fetus, vaginal bleeding, negative quality of life are the influential factors for vomiting during pregnancy. Prenatal health education should be strengthened for young pregnant women. Suitable maintenance for pregnant woman life should be performed to reduce the amount of negative stimulus.

An update on acupuncture point injection

This overview reports the global research advances in acupuncture point injection in the last 5 years. Acupuncture point injection can be applied to a wide range of curable diseases, predominantly those involving pain, but it has poor clinical evidence. Progress has been attained in the mechanism research on acupuncture point injection, but further studies remain necessary. With the reported adverse effects of acupuncture point injection, the need to standardize its clinical procedure has become urgent.

Improved tolerance of maize (Zea mays L.) to heavy metals by colonization of a dark septate endophyte (DSE) Exophiala pisciphila

Dark septate endophytes (DSE) are ubiquitous and abundant in stressful environments including heavy metal (HM) stress. However, our knowledge about the roles of DSE in improving HM tolerance of their host plants is poor. In this study, maize (Zea mays L.) was inoculated with a HM tolerant DSE strain Exophiala pisciphila H93 in lead (Pb), zinc (Zn), and cadmium (Cd) contaminated soils. E. pisciphila H93 successfully colonized and formed typical DSE structures in the inoculated maize roots. Colonization of E. pisciphila H93 alleviated the deleterious effects of excessive HM supplements and promoted the growth of maize (roots and shoots) under HM stress conditions, though it significantly decreased the biomass of inoculated maize under no HM stress. Further analysis showed that the colonization of E. pisciphila H93 improved the tolerance of maize to HM by restricting the translocation of HM ions from roots to shoots. This study demonstrated that under higher HM stress, such a mutual symbiosis between E. pisciphila and its host (maize) may be an efficient strategy to survive in the stressful environments.