Objective: To investigate the association between muscle mass and quality of life in adults in Shaanxi adults. Methods: The data in this analysis were part of the baseline survey of the Regional Ethnic Cohort Study in Northwest China from June 2018 to May 2019 in Shaanxi Province. The participants' quality of life, including physical component summary (PCS) and mental component summary (MCS), was assessed by the 12-Item Short Form Survey, and the Body Fat Determination System measured muscle mass. A logistic regression model with adjustment for confounding factors was established to analyze the association between muscle mass and quality of life in different genders. Further, sensitivity and subgroup analyses were conducted to explore its stability. Finally, a restricted cubic spline was employed to investigate the dose-response relationship between muscle mass and quality of life in different genders. Results: A total of 20 595 participants were included, with an average age of 55.0, and 33.4% were male. After controlling for potential confounders, compared with the Q₁ group, the risk of low PCS was reduced by 20.6% (OR=0.794, 95%CI: 0.681-0.925) and the risk of low MCS was lower reduced by 20.1% (OR=0.799, 95%CI: 0.689-0.926) in female Q₅ groups. Compared with the Q₁ group, the risk of low PCS was reduced by 24.4% (OR=0.756, 95%CI: 0.644-0.888) in the male Q₂ group. However, no significant association between muscle mass and MCS in males has been found. In females, restricted cubic spline analysis showed a significant linear dose-response relationship between muscle mass and PCS and MCS. Conclusions: There is a positive association between muscle mass and quality of life in Shaanxi adults, especially females. With the increase in muscle mass, the physical and mental functions of the population continue to improve.
Humans ; Female ; Adult ; Male ; Quality of Life ; Cohort Studies ; Adipose Tissue ; China ; Muscles

Isotemporal substitution model is a powerful tool to explore the real association between physical behavior and health outcomes, which has the potential of the application in large-scale cohort study. This paper systematically introduces the principle of isotemporal substitution model and its implementation method in specific analysis to provide analytical ideas for the epidemiological research related to physical behavior in China. The baseline data of Regional Ethic Cohort Study in Northwest China conducted in Shaanxi province were used to analyze the relationship between physical behavior and cardiovascular disease with single-factor model, partition model and isotemporal substitution model. The advantages and disadvantages of different models were compared, and the advantages of isotemporal substitution model in quantifying physical activity health risk were introduced. Isotemporal substitution model could qualify physical behavior and health outcomes, which has wide application value in epidemiological research.
Humans ; Cohort Studies ; Epidemiologic Studies ; Cardiovascular Diseases ; China/epidemiology*

Retraction Note to: J Zhejiang Univ-Sci B (Biomed & Biotechnol) 2019 20(3):238-252. https://doi.org/10.1631/jzus.B1800122. The authors have retracted this article (Guo et al., 2019) because some data from the original literature had not been converted to appropriate units in the paper, which resulted in deviation of the meta-analysis results. For example, for the forest plot used to examine associations between PM exposure and the risk of adverse birth outcomes, the estimates from Brauer et al. (2008), Pedersen et al. (2013), Zhao et al. (2015), and Hansen et al. (2006) were on the originally reported scales of 1 µg/m, 10 µg/m, 10 µg/m, and Inter Quartile Range, respectively. None of these estimates had been converted to 20 µg/m increase scale that was stated in the article. Similar problem exists in the analysis on associations between NO exposure and risk of adverse birth outcomes. Therefore, the results of the meta-analysis are misleading. All authors have agreed to this retraction and express their deepest apologies to the original authors, publishers, and readers.

Several reviews have assessed the relationship between exposure to ambient air pollution and adverse birth outcomes during pregnancy, but the results remain controversial. The objective of this study was to assess this correlation quantitatively and to explore sources of heterogeneity. We included all published case-control or cohort studies that evaluated the correlation between ambient air pollution and low birth weight (LBW), preterm birth (PTB), and small for gestational age (SGA). Analytical methods and inclusion criteria were provided on the PROSPERO website (CRD42018085816). We evaluated pooled effects and heterogeneity. Subgroup analyses (grouped by exposure period, study settings, study design, exposure types, data source, Newcastle-Ottawa quality score (NOS), and adjustment for smoking or meteorological factors) were also conducted and publication bias was examined. The risk of bias in systematic reviews (ROBIS) tool was used to evaluate the overall risk of bias in this review. Forty studies met the inclusion criteria. We observed pooled odds ratios (ORs) of 1.03-1.21 for LBW and 0.97-1.06 for PTB when mothers were exposed to CO, NO₂, NO_x, O₃, PM_2.5, PM₁₀, or SO₂ throughout their pregnancy. For SGA, the pooled estimate was 1.02 in relation to NO₂ concentrations. Subgroup analysis and sensitivity analysis decreased the heterogeneity to some extent, such as the subgroups of continuous measures (OR=0.98 (0.97-0.99), I²=0.0%) and NOS>7 (OR=0.98 (0.97-0.99), I²=0.0%) in evaluating the association between PTB and NO₂. This review was completed with a low risk of bias. High concentrations of air pollution were significantly related to the higher risk of adverse birth outcomes. However, the sources of heterogeneity among studies should be further explored.
Air Pollutants/adverse effects* ; Air Pollution/adverse effects* ; Bias ; Environmental Exposure ; Female ; Humans ; Infant, Low Birth Weight ; Infant, Newborn ; Infant, Premature ; Infant, Small for Gestational Age ; Maternal Exposure ; Odds Ratio ; Pregnancy ; Pregnancy Outcome ; Premature Birth/epidemiology* ; Risk Assessment

OBJECTIVE: This study investigated complementary feeding practices among four ethnic groups (Han, Uygur, Tibetan, and Zhuang) based on a cross-sectional survey in rural western China. METHODS: In 2005, a stratified multistage cluster random sampling method was used to recruit 9712 children (7411 Han, 1032 Uygur, 678 Tibetan, and 591 Zhuang) between 6 and 35 months of age and their mothers from 45 counties in 10 provinces (autonomous regions, municipalities) in western China. RESULTS: The rates of early introduction (before 6 months) of complementary foods in four ethnic groups (Han, Uygur, Tibetan, and Zhuang) were 71.30%, 95.95%, 82.40%, and 72.30%, respectively. The Infant and Child Feeding Index (ICFI) for Uygur and Tibetan children was lower than that for Han children at all age groups. Uygur children were more likely to have unqualified ICFI compared with Han children in a multivariate logistic regression (odds ratio (OR)=5.138, 95% confidence interval (CI): 4.340-6.084). A higher level of maternal education, greater family wealth, and the availability of complementary feeding educational materials decreased the likelihood of an unqualified ICFI. The nutritional status of children (Han, Tibetan, and Zhuang) with qualified ICFI was better than that for children with unqualified ICFI. CONCLUSIONS Appropriate interventions are required to improve complementary feeding practices in rural western China.
Adult ; Asian People ; Child, Preschool ; China ; Cluster Analysis ; Cross-Sectional Studies ; Educational Status ; Ethnicity ; Feeding Behavior/ethnology* ; Female ; Humans ; Infant ; Infant Nutritional Physiological Phenomena/ethnology* ; Infant, Newborn ; Male ; Multivariate Analysis ; Nutritional Status ; Odds Ratio ; Rural Population ; Social Class ; Surveys and Questionnaires ; Young Adult

BACKGROUNDPreterm birth is a common cause of death in newborns and may result from many determinants, but evidence for the socioeconomic and environmental determinants of preterm birth in Tibetan women of childbearing age is limited. The aim of this study was to understand the current status of preterm birth in native Tibetan women and investigate the socioeconomic and environmental determinants.

METHODSData were drawn from a cohort study which was conducted from August 2006 to August 2012 in rural Lhasa, Tibet, China. A total of 1419 Tibetan pregnant women were followed from 20 weeks' gestation until delivery; the loss to follow-up rate was 4.69%. The incidence of preterm birth was estimated to show the status of preterm births in Tibet. Logistic regression models for longitudinal data were established, and odds ratios (ORs) together with 95% confidence intervals (CIs) were used to evaluate the association between the occurrence of preterm birth and 16 selected potential determinants based on the hierarchical conceptual frame.

RESULTSThe incidence of preterm birth was 4.58% (95% CI = 3.55-5.80%). After adjusting for health-related variables of the mothers and newborns, socioeconomic and environmental determinants associated with preterm birth included season (spring: OR = 0.28, 95% CI = 0.09-0.84; autumn: OR = 0.21, 95% CI = 0.06-0.69; and winter: OR = 0.31, 95% CI = 0.12-0.82) and calendar year of delivery (2010: OR = 5.03, 95% CI = 1.24-20.35; 2009: OR = 6.62, 95% CI = 1.75-25.10; and 2007-2008: OR = 5.93, 95% CI = 1.47-23.90).

CONCLUSIONSThe incidence of preterm birth among native Tibetan women was low and there was a decreasing trend in recent years; however, it is still essential to strengthen seasonal maternal care, extend the spacing between pregnancies, and reinforce adequate maternal nutrition.

Objective To analyze the factors influencing the occurrence of macrosomia so as to provide a theoretical basis for the prevention of macrosomia.Methods The data were selected from the findings of Survey on Prevalence and Risk Factors for Birth Defects in Shaanxi Province.This study intended to select data of macrosomia in Xianyang City and its influencing factors for statistical analysis.The rates were compared by χ2 ;the influencing factors were analyzed by univariate and multivariate Logistic regression.Results The incidence of fetal macrosomia among single live birth neonates in Xianyang was 5.2%.The incidence of macrosomia was 6.5%in males and 4.2% in females,with a significant difference (P <0.001).From 2010 to 2013 the annual incidence rate of macrosomia was 5.4%,6.2%,5.9% and 4.4%,with no significant difference (P =0.151).The incidence rate of macrosomia in urban and rural areas was 6.3% and 5.5%,respectively,without significant difference (P =0.556).The incidence of macrosomia was 3.2% in Binxian County,5.6% in Changwu County,6.7% in Liquan County,5.4% in Qianxian County,8.0% in Wugong County,and 4.2% in Xunyi County,with significant differences (P <0.001).Logistic regression analysis showed that the occurrence of macrosomia was related to the baby's sex,mother's age,the times of pregancy,the time of antenatal care,alcohol intake during pregnancy and father's occupation.Conclusion The incidence of macrosomia of Xianyang from 2010 to 2013 was close to the national average.The sex of baby,mother's age,the times of pregnancy,the times of antenatal care,drinking history during pregnancy and father's occupation may affect the occurrence of macrosomia.

Background: Preterm birth is a common cause of death in newborns and may result from many determinants, but evidence for the socioeconomic and environmental determinants of preterm birth in Tibetan women of childbearing age is limited. The aim of this study was to understand the current status of preterm birth in native Tibetan women and investigate the socioeconomic and environmental determinants. Methods: Data were drawn from a cohort study which was conducted from August 2006 to August 2012 in rural Lhasa, Tibet, China. A total of 1419 Tibetan pregnant women were followed from 20 weeks' gestation until delivery; the loss to follow?up rate was 4.69%. The incidence of preterm birth was estimated to show the status of preterm births in Tibet. Logistic regression models for longitudinal data were established, and odds ratios (ORs) together with 95% confidence intervals (CIs) were used to evaluate the association between the occurrence of preterm birth and 16 selected potential determinants based on the hierarchical conceptual frame. Results: The incidence of preterm birth was 4.58% (95% CI = 3.55–5.80%). After adjusting for health?related variables of the mothers and newborns, socioeconomic and environmental determinants associated with preterm birth included season (spring: OR = 0.28, 95%CI = 0.09–0.84; autumn: OR = 0.21, 95% CI = 0.06–0.69; and winter: OR = 0.31, 95% CI = 0.12–0.82) and calendar year of delivery (2010: OR = 5.03, 95% CI = 1.24–20.35; 2009: OR = 6.62, 95% CI = 1.75–25.10; and 2007–2008: OR = 5.93, 95% CI = 1.47–23.90). Conclusions: The incidence of preterm birth among native Tibetan women was low and there was a decreasing trend in recent years;however, it is still essential to strengthen seasonal maternal care, extend the spacing between pregnancies, and reinforce adequate maternal nutrition.

OBJECTIVEUsing infant and child feeding index (ICFI) to evaluate the relationship between infant feeding and physical development indicators in rural areas of Lhasa.

METHODSIn July and August 2010 in the rural areas of Lhasa, the multi-stage cluster random sampling method was adopted to select 540 Tibetan children who were between 6 to 35 months of age. There were 70, 79 and 391 cases in 6 to 8, 9 to 11 and 12 to 35-month-old group respectively. The basic status of infants, information about breastfeeding and complementary feeding were collected by using designed questionnaires. Their height and weight were measured to calculate the children's weight for age Z-score (WAZ), height for age Z-score (HAZ) and weight for height Z-score (WHZ) and assess feeding index score (out of 17 scores) and analyze the relationship between feeding index and HAZ, WAZ and WHZ.

RESULTSThe mean ICFI score of 540 cases was 8.90 ± 2.82.It was 6.84 ± 3.16, 8.16 ± 2.78 and 9.41 ± 2.55 for 6 to 8, 9 to 11 and 12 to 35-month-old infants respectively. There was significant difference between the different month group (F = 30.99, P < 0.05).For the three month groups, the scores of WAZ were 0.10 ± 1.18, -0.09 ± 1.20 and -0.38 ± 0.96; HAZ were -0.60 ± 1.68, -1.02 ± 1.72 and -1.30 ± 1.30; WHZ were 0.62 ± 1.23, 0.69 ± 0.96 and 0.43 ± 0.95 respectively. The ICFI scores of 9 to 11, 12 to 35 and 6 to 35-month-old infants were positively correlated with HAZ (correlation coefficients were 0.25,0.12 and 0.09 respectively, all P values <0.05). There was no correlation with WAZ (correlation coefficients were 0.15,0.08 and 0.03 respectively, all P values >0.05) and WHZ (correlation coefficients were -0.08, -0.02, and -0.07 respectively, all P values >0.05). There were no correlation between ICFI score with HAZ, WAZ and WHZ for 6 to 8 month-old infants (correlation coefficient were 0.06,0.16 and -0.07 respectively, all P values >0.05).

CONCLUSIONTo some extent, the feeding index can effectively reflect the growth status of these infants and can serve as a comprehensive assessment of feeding situations among Tibetan children in rural areas of Lhasa.

Breast Feeding ; Child Development ; Child, Preschool ; China ; Female ; Humans ; Infant ; Infant Food ; Male ; Nutritional Status ; Rural Population ; Somatotypes

OBJECTIVETo analyze the associations between menopause and hypertension/isolated systolic hypertension (ISH) among rural females in Hanzhong, Shaanxi Province, China.

METHODSIn this cross-sectional study, 3030 residents were selected by stratified random sampling and investigated by questionnaire survey and physical examinations. Data of the females were analyzed to explore the impact of menopause on blood pressure by quantile regression and to investigate the associations between menopause and hypertension, ISH, and isolated distolic hypertension (IDH) by logistic regression.

RESULTSThe number of premenopausal and postmenopausal women was 965 and 998. The average age was (41.0 ± 8.07) years in the premenopausal group and (58.0±7.12) years in the postmenopausal group (P<0.001). The prevalence of hypertension among the premenopausal group and postmenopausal group was 21.9% and 49.3%, respectively. Quantiles regression analysis showed that the impact of menopause on systolic blood pressure increased as the percentile increased. The diastolic blood pressure (DBP) of the premenopausal group was significantly lower than that in the postmenopausal at q ≥ 0.40(DBP = 84 mmHg,1 mmHg = 0.133 kPa) percentile points (P<0.05), while the difference was not significant at q≤ 0.30 (DBP=80 mmHg) percentile points(P>0.05). After the potential confounders including age, education level, marriage, occupational, hyperlipidemia, family history, exercise, sleep, watching TV, smoking, passive smoking, alcohol consumption, body mass index, wealth index, waist circumference were controlled, positive associations were observed between menopause and hypertension/ISH in logistic regression models.

CONCLUSIONSMenopause is positively related with hypertension/ISH. More effective interventions should be taken to prevent hypertension and ISH among rural women.

Adult ; Aged ; Blood Pressure ; China ; epidemiology ; Cross-Sectional Studies ; Female ; Humans ; Hypertension ; epidemiology ; physiopathology ; Menopause ; Middle Aged ; Rural Population ; Surveys and Questionnaires