Composite dietary antioxidant intake and osteoporosis likelihood in premenopausal and postmenopausal women: a population-based study in the United States.

OBJECTIVE: Osteoporosis is a skeletal disease characterized by low bone mass, reduced bone strength, and increased fracture risk. We aimed to investigate the association between combined dietary antioxidant intake and the likelihood of osteoporosis in premenopausal and postmenopausal women, based on data from the National Health and Nutrition Examination Survey. METHODS: Nutrient intake data were obtained using two 24-hour recalls. Composite dietary antioxidant index (CDAI), which refers to the intake amounts of ß-carotene, vitamin A, vitamin C, vitamin E, selenium, zinc, copper, and iron, was then constructed. Prevalent osteoporosis was defined according to bone mineral density T scores of ≤ -2.5 and self-reports. Multiple logistic and Poisson regression models were used for association analyses. RESULTS: A total of 3,418 participants (1,157 premenopausal and 2,261 postmenopausal women) 40 years or older were included, 776 (22.70%) of whom had prevalent osteoporosis. In terms of individual nutrients, postmenopausal women in the highest CDAI quartiles for dietary ß-carotene, vitamin A, vitamin C, and iron intakes had a low likelihood of osteoporosis. Regarding the CDAI-osteoporosis association, postmenopausal women in the highest quartile were less likely to have osteoporosis (OR Q3 vs Q1 , 0.64; 95% CI, 0.43-0.96; OR Q4 vs Q1 , 0.56; 95% CI, 0.35-0.89; P for trend = 0.013), after controlling for covariates. CONCLUSIONS: CDAI was negatively associated with the likelihood of osteoporosis in postmenopausal women. Our findings suggest that the combined intake of antioxidant nutrients can help reduce the likelihood of osteoporosis in women.

[Optimal gestational weight gain for Chinese urban women].

OBJECTIVE: To examine optimal gestational weight gain(GWG) for Chinese pregnant women. METHODS: A total of 6998 women with singleton and term pregnancy recruited to the Tongji Maternal and Child Health Cohort during January 2013 to May 2016 in Wuhan, Hubei were included. Information on sociodemographic, medical and family history of disease was obtained by questionnaire, body weight and height were measured at the first antenatal care during 8-16 weeks of gestation. Prenatal weight of mothers were measured, and gestational week, mode of delivery, pregnancy complications, gender of newborn, birth weight and length were collected from medical records after delivery. Restricted cubic spline was used to model nonlinear relationships between GWG and the occurrence of small for gestational age(SGA), large for gestational age(LGA), low birth weight(LBW), macrosomia, cesarean, gestational hypertension(GH)and gestational diabetes mellitus(GDM), respectively. The GWG of the lowest risks for adverse pregnant outcomes was regarded as optimal GWG recommended by Tongji(TJ) for pregnant women. The P25-P75 of GWG was defined as the optimal GWG recommended by percentile method. Logistic regression was used to analyze the effect of excessive or insufficient GWG on adverse pregnancy outcomes, while the recommendations of TJ and percentile method were used as references, respectively. RESULTS: (1) The GWG with lower risk of adverse pregnant outcomes based on pre-gravid body mass index(BMI) are 12. 0-17. 0 kg for underweight, 9. 0-14. 0 kg for normal weight and 7. 0-11. 0 kg for overweight, respectively, which are defined as TJ recommendations. The recommended GWG by percentile method are 14. 0-19. 0 kg for underweight, 13. 0-19. 0 kg for normal weight, 10. 8-18. 0 kg for overweight and 9. 0-15. 8 kg for obesity, respectively. (2) Compared to women gain within the TJ recommendations, OR of LGA is 2. 94(95%CI 2. 31-3. 73), macrosomia is 3. 13(95%CI 2. 38-4. 13), cesarean is 1. 53(95%CI 1. 38-1. 71) and GH is 2. 18(95%CI 1. 50-3. 17) for those with excessive GWG, OR of SGA is 1. 82(95%CI 1. 32-2. 53) for those who gain less. The corresponding ORs according to percentile method are 2. 11(95%CI 1. 76-2. 54) for LGA, 2. 16(95%CI 1. 76-2. 65) for macrosomia, 1. 53(95%CI 1. 36-1. 72) for cesarean, 1. 39(95%CI 1. 02-1. 90) for GH and 1. 60(95%CI 1. 29-1. 99) for SGA, respectively. CONCLUSION: The optimal GWG of Chinese pregnant women recommended by the study are 12. 0-17. 0 kg for pre-gravid underweight women, 9. 0-14. 0 kg for normal weight women and 7. 0-11. 0 kg for overweight, respectively.

Association of Bone Turnover Levels with MTHFR Gene Polymorphisms among Pregnant Women in Wuhan, China.

Pregnancy is a critical stimulator of bone mineral resorption. We used to find the MTHFR gene polymorphisms are related with blood lead levels among pregnant women. Pregnancy-stimulated bone turnover may be associated with MTHFR gene polymorphisms too. In this article, we aimed to determine the relationship between MTHFR gene polymorphisms and bone turnover rates among the pregnant women. The participants including pregnant and non-pregnant women were selected and recruited during their routine prenatal or physical examination from July to October in 2012. A total of 1000 participants, including 250 pregnant women in the first, second, and third trimesters and 250 non-pregnant women, were enrolled in the study. Finally, after excluding 27 participants unable to provide blood samples, 973 eligible participants (i.e., 234,249, and 248 pregnant women in the first, second, and third trimesters, respectively, and 242 non-pregnant women) were included in the research. The MTHFR gene 1298CC homozygote carriers were more susceptible to yield higher plasma homocysteine levels than the 1298AA/AC carriers, with standardized coefficients of 0.086 (P<0.05) and 0.104 (P<0.01) of all the participants and the pregnant women, respectively. The MTHFR gene 1793AA homozygote carriers more likely showed higher plasma osteocalcin levels (standardized ß=0.091,P<0.01) than the 1793GG/GA carriers among all the subjects. Plasma homocysteine levels were positively correlated with blood lead levels among the participants and the pregnant women with standardized coefficients of 0.320 (P<0.01) and 0.179 (P<0.01), respectively. Plasma osteocalcin levels were positively associated with blood lead levels among pregnant and non-pregnant women with standardized coefficients of 0.084 (P<0.05) and 0.125 (P<0.01), respectively. In conclusion, homocysteine and osteocalcin contents in plasma are associated with the MTHFR gene A1298C polymorphism and blood lead levels among pregnant women. The MTHFR gene A1298C polymorphism-related homocysteine is a possible risk factor for increased blood lead levels among Chinese women.

The association between caesarean delivery and the initiation and duration of breastfeeding: a prospective cohort study in China.

BACKGROUND/OBJECTIVES: Breastfeeding is of great benefit to infants and their mothers. Caesarean delivery (CD) have increased worldwide in recent years and emerging evidence has implied that CD may influence the initiation and duration of breastfeeding. However, the findings are inconsistent and intricate. The aim of this study is to illuminate the association between the CD and the initiation and duration of breastfeeding in the first 6 months postpartum. SUBJECTS/METHODS: A total of 2058 mother-infant pairs were studied in this prospective study. Delivery information was obtained from birth records. Feeding information in the first 6 months postpartum were collected from face-to-face interviews. Logistic regression was used to explore the association between CD and the initiation and duration of breastfeeding. RESULTS: After adjustment for potential confounders, CD was significantly associated with the unsuccessful initiation of breastfeeding [odds ratio (OR): 1.943, 95% confidence interval (CI): 1.050-3.597] and delayed initiation of breastfeeding [OR: 1.450, (95% CI: 1.041-2.019)], when compared with vaginal delivery (VD). More importantly, for mothers who had initiated breastfeeding, CD was associated with significantly higher risks of an inability to sustain full breastfeeding (OR: 1.369, 95% CI: 1.128-1.662), any breastfeeding at 3 months postpartum (OR: 1.715, 95% CI: 1.265-2.325) and any breastfeeding at 6-month postpartum (OR: 1.462, 95% CI: 1.174-1.820). CONCLUSIONS: CD is an independent risk factor for the inability to initiate and sustain breastfeeding. It is desirable to reduce the CD rate and provide specific breastfeeding support during early postpartum period to CD mothers.

Dose-response relationship between blood lead levels and hematological parameters in children from central China.

BACKGROUND: Lead is a heavy metal that can affect the human hematological system. However, reports are limited on the dose-response relationship between blood lead levels (BLLs) and hematological parameters in children. This study aimed to explore the dose-response relationship between BLLs and hematological measurements among children in China. METHODS: A cross-sectional design was used. A total of 743 children aged 5-8 years were recruited from two counties in central China. The BLLs and blood levels of iron, zinc, and calcium were determined, and hematological parameters were measured. RESULTS: All hematological measurements and BLLs were logarithm-transformed to ensure a normal distribution. The geometric mean of the BLLs of all children was 82.4 µg/L. Forty-one percent of the children had BLLs ≥ 100 µg/L. The lead-poisoning percentages of the children were significantly associated with gender, age, district of residence, and environmental lead exposure level. Multivariate linear regression analyses showed no significant linear correlation between BLL and each hematological parameter among the children with BLLs ≥ 100 µg/L. The analyses also revealed a small increase in red blood cell count (RBC) with increasing BLLs in the BLLs < 100 µg/L group (ß = 0.03, P =  0.048). A negative association was noted between BLLs and blood platelet (PLT) count in the children with BLLs < 100 µg/L (ß = -0.90, P < 0.001). Logistic regression analyses showed that BLLs were significantly associated with decreased hemoglobin (Hb) levels, RBC counts, PLT counts and mean corpuscular hemoglobin (MCH) after adjusting for potential confounders. Such analyses also revealed a dose-response relationship between the BLLs and hematological parameters (Hb level, RBC count, and PLT count). The children with BLLs ≥ 100 µg/L were 2.72, 2.51, and 3.76 times more likely to achieve decreased RBC counts, Hb levels and PLT counts, respectively, compared to those with BLLs < 100 µg/L. Compared with children with BLLs < 100 µg/L, those with BLLs ≥ 100 µg/L were 3.16 and 4.38 times more likely to show decreased Hb levels and PLT counts respectively in the high-level lead-exposure group and 4.33 times more likely to achieve a decreased PLT count in the low-level lead-exposure group. The individuals with BLLs of the highest quartile were 3.65, 5.87, and 29.23 times more likely to exhibit decreased Hb levels, RBC counts, and PLT counts, respectively, than the children with BLLs of the lowest quartile. CONCLUSION: Our findings suggested a negative association between BLLs and hematological indicators (Hb level, RBC count, PLT count and MCH). A strong negative, non-linear dose-response relationship was also showed between BLLs and hematological parameters (Hb level, RBC count, and PLT count).

Early feeding of larger volumes of formula milk is associated with greater body weight or overweight in later infancy.

BACKGROUND: The relation between infant feeding and growth has been extensively evaluated, but studies examining the volume of formula milk consumption on infant growth are limited. This study aimed to examine the effects of early feeding of larger volumes of formula on growth and risk of overweight in later infancy. METHODS: In total, 1093 infants were studied prospectively. Milk records collected at 3 mo of age were used to define the following 3 feeding groups: breast milk feeding (BM, no formula), lower-volume formula milk feeding (LFM, <840 ml formula/d), and higher-volume formula milk feeding (HFM, ≥840 ml formula/d). Body weight and length were measured at 3 time points of 3, 6 and 12 mo of age. RESULTS: The results showed that the difference in weight and length between the HFM and BM infants was significant at 3 mo of age (P < 0.05) and continued until 12 mo of age (P < 0.001). The adjusted mean changes in weight-for-length z-scores (WLZ) and BMI-for-age z-scores (BAZ) from 3 to 6 mo of age were significantly higher in HFM and LFM group than in BM group. Two-way interactions between feeding practice and age intervals were significant for WLZ changes (P = 0.002) and BAZ changes (P = 0.017). Compared with BM-fed infants, infants fed with HFM had 1.60-fold (95% CI 1.05-2.44) higher odds of greater body weight (1SD < WLZ ≤2 SD) at the age of 6 mo and 1.55-fold (95% CI 1.01-2.37) higher odds of greater body weight and 2.13-fold (95% CI 1.03-4.38) higher odds of overweight (WLZ > 2 SD) at the age of 12 mo. CONCLUSION: Feeding higher volumes of formula in early infancy is associated with greater body weight and overweight in later infancy.

Risk factors for low birth weight and preterm birth: A population-based case-control study in Wuhan, China.

Low birth weight (LBW) and preterm birth (PB) are associated with newborn mortality and diseases in adulthood. We explored factors related to LBW and PB by conducting a population-based case-control study from January 2011 to December 2013 in Wuhan, China. A total of 337 LBW newborn babies, 472 PB babies, and 708 babies with normal birth weights and born from term pregnancies were included in this study. Information of newborns and their parents was collected by trained investigators using questionnaires and referring to medical records. Univariate and logistic regression analyses with the stepwise selection method were used to determine the associations of related factors with LBW and PB. Results showed that maternal hypertension (OR=6.78, 95% CI: 2.27-20.29, P=0.001), maternal high-risk pregnancy (OR=1.53, 95% CI: 1.06-2.21, P=0.022), and maternal fruit intake ≥300 g per day during the first trimester (OR=1.70, 95% CI: 1.17-2.45, P=0.005) were associated with LBW. BMI ≥24 kg/m2 of mother prior to delivery (OR=0.48, 95% CI: 0.32-0.74, P=0.001) and gestation ≥37 weeks (OR=0.01, 95% CI: 0.00-0.02, P<0.034) were protective factors for LBW. Maternal hypertension (OR=3.36, 95% CI: 1.26-8.98, P=0.016), maternal high-risk pregnancy (OR=4.38, 95% CI: 3.26-5.88, P<0.001), maternal meal intake of only twice per day (OR=1.88, 95% CI: 1.10-3.20, P=0.021), and mother liking food with lots of aginomoto and salt (OR=1.60, 95% CI: 1.02-2.51, P=0.040) were risk factors for PB. BMI ≥24 kg/m2 of mother prior to delivery (OR=0.66, 95% CI: 0.47-0.93, P=0.018), distance of house from road ≥36 meters (OR=0.72, 95% CI: 0.53-0.97, P=0.028), and living in rural area (OR= 0.60, 95% CI: 0.37-0.99, P=0.047) were protective factors for PB. Our study demonstrated some risk factors and protective factors for LBW and PB, and provided valuable information for the prevention of the conditions among newborns.

Risk Factors for Low Birth Weight and Preterm Birth: A Population-based Case-control Study in Wuhan, China / 华中科技大学学报（医学）（英德文版）

Low birth weight (LBW) and preterm birth (PB) are associated with newborn mortality and diseases in adulthood.We explored factors related to LBW and PB by conducting a population-based case-control study from January 2011 to December 2013 in Wuhan,China.A total of 337 LBW newborn babies,472 PB babies,and 708 babies with normal birth weights and born from term pregnancies were included in this study.Information of newborns and their parents was collected by trained investigators using questionnaires and referring to medical records.Univariate and logistic regression analyses with the stepwise selection method were used to determine the associations of related factors with LBW and PB.Results showed that maternal hypertension (OR=6.78,95％ CI:2.27-20.29,P=0.001),maternal high-risk pregnancy (OR=1.53,95％ CI:1.06-2.21,P=0.022),and maternal fruit intake ≥300 g per day during the first trimester (OR=1.70,95％ CI:1.17-2.45,P=0.005) were associated with LBW.BMI ≥24 kg/m2 of mother prior to delivery (OR=0.48,95％ CI:0.32-0.74,P=0.001) and gestation ≥37 weeks (OR=0.01,95％ CI:0.00-0.02,P＜0.034) were protective factors for LBW.Maternal hypertension (OR=3.36,95％ CI:1.26-8.98,P=0.016),maternal high-risk pregnancy (OR=4.38,95％ CI:3.26-5.88,P＜0.001),maternal meal intake of only twice per day (OR=1.88,95％ CI:1.10-3.20,P=0.021),and mother liking food with lots of aginomoto and salt (OR=1.60,95％ CI:1.02-2.51,P=0.040) were risk factors for PB.BMI ≥24 kg/m2 of mother prior to delivery (OR=0.66,95％ CI:0.47-0.93,P=0.018),distance of house from road ≥36 meters (OR=0.72,95％ CI:0.53-0.97,P=0.028),and living in rural area (OR=0.60,95％ CI:0.37-0.99,P=0.047) were protective factors for PB.Our study demonstrated some risk factors and protective factors for LBW and PB,and provided valuable information for the prevention of the conditions among newborns.

Parity and All-cause Mortality in Women and Men: A Dose-Response Meta-Analysis of Cohort Studies.

To quantitatively assess the association between parity and all-cause mortality, we conducted a meta-analysis of cohort studies. Relevant reports were identified from PubMed and Embase databases. Cohort studies with relative risks (RRs) and 95% confidence intervals (CIs) of all-cause mortality in three or more categories of parity were eligible. Eighteen articles with 2,813,418 participants were included. Results showed that participants with no live birth had higher risk of all-cause mortality (RR= 1.19, 95% CI = 1.03-1.38; I(2) = 96.7%, P < 0.001) compared with participants with one or more live births. Nonlinear dose-response association was found between parity and all-cause mortality (P for non-linearity < 0.0001). Our findings suggest that moderate-level parity is inversely associated with all-cause mortality.

Association of blood lead levels with methylenetetrahydrofolate reductase polymorphisms among Chinese pregnant women in Wuhan city.

BACKGROUND: Pregnancy is an important stimulus of bone lead release. Elevated blood lead levels (BLLs) may cause adverse pregnancy outcomes for mothers and harmful lead effects on fetuses. However, the reports about maternal BLL changes during pregnancy are conflicting to some extent. This article is to explore the variations in BLLs among pregnant women. The relationships of BLLs with methylenetetrahydrofolate reductase (MTHFR) gene C677T, A1298C, and G1793A polymorphisms, which are associated with bone resorption, were also studied. A total of 973 women, including 234, 249, and 248 women in their first, second, and third trimesters, respectively, and 242 non-pregnant women, were recruited at the Wuhan Women and Children Medical Health Center. METHODS: BLLs were determined using a graphite furnace atomic absorption spectrometer. Single-nucleotide polymorphisms of MTHFR were identified with the TaqMan probe method. RESULTS: The geometric mean (geometric standard deviation) of BLLs was 16.2 (1.78) µg/L for all participants. All the studied MTHFR alleles were in Hardy-Weinberg equilibrium. Multiple-linear regression analysis revealed the following results. Among the pregnant women, those that carried MTHFR 677CC (i.e. wild-genotype homozygote) and 1298CC (i.e. mutant-genotype homozygote) exhibited higher BLLs than those that carried 677CT/TT (standardized ß = 0.074, P = 0.042) and 1298AC/AA (standardized ß = 0.077, P = 0.035) when other covariates (e.g., age, no. of children, education and income, etc.) were adjusted. The BLLs of pregnant women consistently decreased during the pregnancy and these levels positively correlated with BMI (standard ß = 0.086-0.096, P<0.05). CONCLUSIONS: The 1298CC mutant-type homozygote in the MTHFR gene is a risk factor for high BLLs among low-level environmental lead-exposed Chinese pregnant women, whose BLLs consistently decreased during gestation.