Maternal gestational diabetes and childhood adiposity risk from 6 to 8 years of age.

BACKGROUND/OBJECTIVE: Previous studies found conflicting results on the association between maternal gestational diabetes mellitus (GDM) and childhood overweight/obesity. This study was to assess the association between maternal GDM and offspring's adiposity risk from 6 to 8 years of age. METHODS: The present study longitudinally followed 1156 mother-child pairs (578 GDM and 578 non-GDM) at 5.9 ± 1.2 years postpartum and retained 912 mother-child pairs (486 GDM and 426 non-GDM) at 8.3 ± 1.6 years postpartum. Childhood body mass index (BMI), waist circumference, body fat and skinfold were measured using standardized methods. RESULTS: Compared with the counterparts born to mothers with normal glucose during pregnancy, children born to mothers with GDM during pregnancy had higher mean values of adiposity indicators (waist circumference, body fat, subscapular skinfold and suprailiac skinfold) at 5.9 and 8.3 years of age. There was a positive association of maternal GDM with changes of childhood adiposity indicators from the 5.9-year to 8.3-year visit, and ß values were significantly larger than zero: +0.10 (95% CI: 0.02-0.18) for z score of BMI for age, +1.46 (95% CI: 0.70-2.22) cm for waist circumference, +1.78% (95% CI: 1.16%-2.40%) for body fat, +2.40 (95% CI: 1.78-3.01) mm for triceps skinfold, +1.59 (95% CI: 1.10-2.09) mm for subscapular skinfold, and +2.03 (95% CI: 1.35-2.71) mm for suprailiac skinfold, respectively. Maternal GDM was associated with higher risks of childhood overweight/obesity, central obesity, and high body fat (Odd ratios 1.41-1.57 at 5.9 years of age and 1.73-2.03 at 8.3 years of age) compared with the children of mothers without GDM. CONCLUSIONS: Maternal GDM was a risk factor of childhood overweight/obesity at both 5.9 and 8.3 years of age, which was independent from several important confounders including maternal pre-pregnancy BMI, gestational weight gain, children's birth weight and lifestyle factors. This significant and positive association became stronger with age.

Interactive effects of gestational diabetes and high pre-pregnancy body mass index on adverse growth patterns of offspring.

AIMS: To examine the independent and interactive effects of maternal gestational diabetes mellitus (GDM) and high pre-pregnancy body mass index (BMI) on the risk of offspring adverse growth patterns. MATERIALS AND METHODS: One thousand six hundred and eighty one mother-child pairs were followed for 8 years in Tianjin, China. Group-based trajectory modelling was used to identify offspring growth patterns. Logistic regression was performed to obtain odds ratios (ORs) and 95% confidence intervals (CIs) of GDM and high pre-pregnancy BMI for offspring adverse growth patterns. Restricted cubic spline was used to identify cut-off points. Additive interactions and multiplicative interactions were used to test interactive effects between GDM and high pre-pregnancy BMI for adverse growth patterns. RESULTS: Four distinct growth patterns were identified in offspring, including normal growth pattern, persistent lean growth pattern, late obesity growth pattern (LOGP), and persistent obesity growth pattern (POGP). Maternal high pre-pregnancy BMI was associated with LOGP and POGP (adjusted OR, 95% CI: 2.38, 1.74-3.25 & 4.92, 2.26-10.73). GDM greatly enhanced the adjusted OR of high pre-pregnancy BMI for LOGP up to 3.48 (95% CI: 2.25-5.38). Additive interactions and multiplicative interactions between both risk factors were significant for LOGP but not for POGP. CONCLUSIONS: Maternal high pre-pregnancy BMI was associated with increased risk of LOGP and POGP, whereas GDM greatly enhanced the risk of high pre-pregnancy BMI for LOGP.

Identifying optimal ranges of weight gain at the end of the second trimester result from a population-based cohort study.

OBJECTIVE: To identify the optimal weight gain at the end of the second trimester. DESIGN: This was a population-based cohort study from the antenatal care system in Tianjin, China. We calculated gestational weight gain (GWG) based on the weight measured in the first trimester and the end of the second trimester. Restricted cubic spline analysis was performed to model the possible non-linear relationships between GWG and adverse outcomes. The optimal GWG was defined as the value of the lowest risk. Non-inferiority margins and the shape of the spline curves identified the recommended ranges in Chinese-specific BMI categories. SETTING: Tianjin Maternal and Child Health Cohort. PARTICIPANTS: Singleton pregnant women aged 18-45 years. RESULTS: In total, 69 859 pregnant women were included. Adverse outcome (including stillbirth, preterm birth, hypertensive disorders of pregnancy, gestational diabetes mellitus, small and large for gestational age) was significantly associated with GWG at the end of the second trimester. The risk score was non-linearly correlated with GWG in the underweight, normal weight and overweight groups. GWG at the end of the second trimester should not be < 7 kg in underweight group. For most normal-weight women, a GWG of about 8 kg is optimal. Pregnant women who are overweight should not have a GWG of more than 9 kg. We advised women with overweight and obesity to keep positive growth of GWG (> 0 kg) in the first and second trimesters. CONCLUSIONS: According to the comprehensive adverse maternal and infant outcomes, we recommend the optimal GWG at the end of the second trimester. This study may provide a considerable reference for weight management.

Aromatic Amino Acids and Their Interactions with Gut Microbiota-Related Metabolites for Risk of Gestational Diabetes: A Prospective Nested Case-Control Study in a Chinese Cohort.

INTRODUCTION: The aim of this study was to explore associations of aromatic amino acids (AAA) in early pregnancy with gestational diabetes mellitus (GDM), and whether high AAA and gut microbiota-related metabolites had interactive effects on GDM risk. METHODS: We conducted a 1:1 case-control study (n = 486) nested in a prospective cohort of pregnant women from 2010 to 2012. According to the International Association of Diabetes and Pregnancy Study Group's criteria, 243 women were diagnosed with GDM. Binary conditional logistic regression was performed to examine associations of AAA with GDM risk. Interactions between AAA and gut microbiota-related metabolites for GDM were examined using additive interaction measures. RESULTS: High phenylalanine and tryptophan were associated with increased GDM risk (OR: 1.72, 95% CI: 1.07-2.78 and 1.66, 1.02-2.71). The presence of high trimethylamine (TMA) markedly increased the OR of high phenylalanine alone up to 7.95 (2.79-22.71), while the presence of low glycoursodeoxycholic acid (GUDCA) markedly increased the OR of high tryptophan alone up to 22.88 (5.28-99.26), both with significant additive interactions. Furthermore, high lysophosphatidylcholines (LPC18:0) mediated both interactive effects. CONCLUSIONS: High phenylalanine may have an additive interaction with high TMA, while high tryptophan may have an additive interaction with low GUDCA toward increased risk of GDM, both being mediated via LPC18:0.

Early prenatal exposure to air pollutants and congenital heart disease: a nested case-control study.

BACKGROUND: Congenital heart disease (CHD) is one of the most common congenital malformations in humans. Inconsistent results emerged in the existed studies on associations between air pollution and congenital heart disease. The purpose of this study was to evaluate the association of gestational exposure to air pollutants with congenital heart disease, and to explore the critical exposure windows for congenital heart disease. METHODS: The nested case-control study collected birth records and the following health data in Tianjin Women and Children's Health Center, China. All of the cases of congenital heart disease from 2013 to 2015 were selected matching five healthy controls for each case. Inverse distance weighting was used to estimate individual exposure based on daily air pollution data. Furthermore, the conditional logistic regression with distributed lag non-linear model was performed to identify the association between gestational exposure to air pollution and congenital heart disease. RESULTS: A total of 8,748 mother-infant pairs were entered into the analysis, of which 1,458 infants suffered from congenital heart disease. For each 10 µg/m3 increase of gestational exposure to PM2.5, the ORs (95% confidence interval, 95%CI) ranged from 1.008 (1.001-1.016) to 1.013 (1.001-1.024) during the 1st-2nd gestation weeks. Similar weak but increased risks of congenital heart disease were associated with O3 exposure during the 1st week and SO2 exposure during 6th-7th weeks in the first trimester, while no significant findings for other air pollutants. CONCLUSIONS: This study highlighted that gestational exposure to PM2.5, O3, and SO2 had lag effects on congenital heart disease. Our results support potential benefits for pregnancy women to the mitigation of air pollution exposure in the early stage, especially when a critical exposure time window of air pollutants may precede heart development.

Relationship between gestational body mass index change and the risk of gestational diabetes mellitus: a community-based retrospective study of 41,845 pregnant women.

BACKGROUND: Gestational diabetes mellitus (GDM) is associated with adverse health consequences for women and their offspring. It is associated with maternal body mass index (BMI) and may be associated with gestational weight gain (GWG). But due to the heterogeneity of diagnosis and treatment and the potential effect of GDM treatment on GWG, the association between the two has not been thoroughly clarified. Compared to body weight, BMI has the advantage that it considers height during the whole course of pregnancy. Understanding BMI changes during pregnancy may provide new evidence for the prevention of GDM. METHODS: This study investigated the BMI change of pregnant women based on a retrospective study covering all communities in Tianjin, China. According to the results of GDM screening at 24-28 weeks of gestation, pregnancies were divided into the GDM group and the non-GDM group. We compared gestational BMI change and GWG in the two groups from early pregnancy to GDM screening. GWG was evaluated according to the IOM guidelines. Logistic regression was applied to determine the significance of variables with GDM. RESULTS: A total of 41,845 pregnant women were included in the final analysis (GDM group, n = 4257 vs. non-GDM group, n = 37,588). BMI gain has no significant differences between the GDM and non-GDM groups at any early pregnancy BMI categories (each of 2 kg/m2), as well as weight gain (P > 0.05). Early pregnancy BMI was a risk factor for GDM (OR 1.131, 95% CI 1.122-1.139). And BMI gain was associated with a decreased risk of GDM in unadjusted univariate analysis (OR 0.895, 95% CI 0.869-0.922). After adjusting on early pregnancy BMI and other confounding factors, the effect of BMI gain was no longer significant (AOR 1.029, 95% CI 0.999-1.061), as well as weight gain (AOR 1.006, 95% CI 0.995-1.018) and GWG categories (insufficient: AOR 1.016, 95% CI 0.911-1.133; excessive: AOR 1.044, 95% CI 0.957-1.138). CONCLUSIONS: BMI in early pregnancy was a risk factor for GDM, while BMI gain before GDM screening was not associated with the risk of GDM. Therefore, the optimal BMI in early pregnancy is the key to preventing GDM.

Abnormal glucose in pre-school children and the association with obesity/physical activity: A large population-based study.

AIM: The rise of diabetes mellitus (DM) and impaired fasting glucose (IFG) in children has become a worldwide challenge, but population-based survey targeted on pre-school children is lacking. The aim of the study was to determine the prevalence of DM and IFG in pre-school children and their association with obesity and susceptible behaviours. METHODS: A population-based survey was conducted and 21,571 Chinese children aged 5-6 years were recruited from 66 kindergartens in Tianjin, China during the year of 2016-2018. Fasting glucose was measured for all participants. Children with fasting glucose over 7.0 mmol/L was defined as DM, and 5.6-6.9 mmol/L was defined as IFG. RESULTS: The prevalence of DM and IFG in the current study among Chinese children aged 5-6 years old was 0.05% and 1.18%, respectively, with significant gender and regional disparities (p < 0.001). The risk of abnormal fasting glucose increased with obesity (OR 1.44, 95% CI 1.00-2.06, p < 0.05), especially with moderate/severe obesity (OR 1.84, 95% CI 1.10-3.10, p < 0.05). Further analyses found that as compared to children who had at least 2 h/day physical activity, physical activity <1 h/day increased the risk of abnormal fasting glucose independently of BMI z-score (OR 1.79, 95% CI 1.10-2.91, p < 0.05). CONCLUSIONS: The study was the first population-based large-scale survey of DM and IFG which targeted on pre-school children, and demonstrated that moderate/severe obesity and inadequate physical activity raised the risk of DM and IFG early from pre-school. The findings highlighted the necessity of early detection for abnormal glucose and control of obesity and susceptible behaviours.

Machine learning risk score for prediction of gestational diabetes in early pregnancy in Tianjin, China.

AIMS: This study aimed to develop a machine learning-based prediction model for gestational diabetes mellitus (GDM) in early pregnancy in Chinese women. MATERIALS AND METHODS: We used an established population-based prospective cohort of 19,331 pregnant women registered as pregnant before the 15th gestational week in Tianjin, China, from October 2010 to August 2012. The dataset was randomly divided into a training set (70%) and a test set (30%). Risk factors collected at registration were examined and used to construct the prediction model in the training dataset. Machine learning, that is, the extreme gradient boosting (XGBoost) method, was employed to develop the model, while a traditional logistic model was also developed for comparison purposes. In the test dataset, the performance of the developed prediction model was assessed by calibration plots for calibration and area under the receiver operating characteristic curve (AUR) for discrimination. RESULTS: In total, 1484 (7.6%) women developed GDM. Pre-pregnancy body mass index, maternal age, fasting plasma glucose at registration, and alanine aminotransferase were selected as risk factors. The machine learning XGBoost model-predicted probability of GDM was similar to the observed probability in the test data set, while the logistic model tended to overestimate the risk at the highest risk level (Hosmer-Lemeshow test p value: 0.243 vs. 0.099). The XGBoost model achieved a higher AUR than the logistic model (0.742 vs. 0.663, p < 0.001). This XGBoost model was deployed through a free, publicly available software interface (https://liuhongwei.shinyapps.io/gdm_risk_calculator/). CONCLUSION: The XGBoost model achieved better performance than the logistic model.

Usefulness of cut-off points of International criteria for prediction of post-partum diabetes and prediabetes among Chinese women with gestational diabetes.

AIMS: This study tests whether cut-off points of the International Association of Diabetes and Pregnancy Study Group's (IADPSG) criteria had threshold effects on post-partum prediabetes and diabetes among Chinese pregnant women with gestational diabetes mellitus (GDM). MATERIALS AND METHODS: A total of 507 out of 1000 women with GDM (948 of them enrolled in a lifestyle trial during pregnancy) turned up for the follow-up study and underwent a 75-g 2-h oral glucose tolerance test. GDM was diagnosed based on the IADPSG's criteria while post-partum diabetes and prediabetes were defined by the World Health Organization's. Generalized logit model was used to obtain odds ratios (OR) and 95% confidence interval (CI) of fasting, 1-h and 2-h plasma glucoses (PGs) for post-partum diabetes and prediabetes. Restricted cubic spline was used to identify any threshold effects. RESULTS: At a median of 9.1 weeks post-partum, 3.7% (n = 19) women developed post-partum diabetes and 35.1% (n = 178) developed post-partum prediabetes. Fasting PG ≥ 5.1 mmol/L was associated with markedly increased risk of post-partum diabetes without a discernible threshold (adjusted OR: 3.87, 95% CI: 1.03-14.52) while 2-h PG ≥ 8.5 and ≥ 9.0 mmol/L had threshold effects on post-partum prediabetes (2.10, 1.33-3.30) and diabetes (4.02, 1.04-15.56). The 1-h PG also had a threshold at ≥10.0 mmol/L for prediabetes (1.67, 1.06-2.64), but it was not significant for post-partum diabetes. CONCLUSIONS: Among Chinese women with GDM, fasting PG ≥ 5.1 mmol/L was associated with post-partum diabetes without any discernible threshold effects while 2-h PG ≥ 8.5 and ≥ 9.0 mmol/L respectively identified women at high risk of post-partum prediabetes and diabetes.

Maternal gestational diabetes and childhood hyperlipidemia.

AIMS: Aim of this study is to assess dyslipidemia risk between children exposed to maternal gestational diabetes mellitus (GDM) and those not exposed. METHODS: We recruited 1144 mother-child pairs (572 GDM and 572 non-GDM women matched by their offspring's age and sex). The age of offspring ranged from 3 to 9 years old. We used general linear models to compare mean values of different lipid profiles among children born to mothers with and without GDM. Logistic regression models were used to assess associations of maternal GDM with abnormal lipid profiles in offspring. RESULTS: After adjustment for maternal and children's characteristics, children born to mothers with GDM had lower mean values of high-density-lipoprotein (HDL) cholesterol (1.40 ± 0.01 vs. 1.50 ± 0.01; p < 0.001) and higher mean levels of triglycerides/HDL cholesterol ratio (0.37 ± 0.01 vs. 0.35 ± 0.01; p < 0.05) in comparison with their counterparts born to mothers without GDM. Multivariate-adjusted odds ratios among children exposed to mothers with GDM compared with the counterparts were 2.11 (95% confidence interval [CI 1.15-3.88]) for low HDL cholesterol and 1.35 (95% CI 1.00-1.81) for high triglycerides/HDL cholesterol ratio, respectively. CONCLUSIONS: Maternal GDM was associated with an increased risk of hyperlipidemia in the offspring during early childhood aged from 3 to 9 years old.

Physical activity and sleep duration during pregnancy have interactive effects on caesarean delivery: a population-based cohort study in Tianjin, China.

BACKGROUND: There were inconsistent findings in the literature regarding the associations of physical activity and sleep duration during pregnancy with caesarean delivery for different reasons. It was also unknown whether physical activity and sleep duration during pregnancy had interactive effects on the risks of different types of caesarean delivery. The study aimed to investigate the effects of physical activity, sleep duration and their interactions on the risk of caesarean delivery for medical reasons and non-medical reasons. METHODS: From October 2010 to August 2012, a prospective population-based cohort of 13,015 pregnant women was established in six central urban districts of Tianjin, China. Pregnancy outcomes were retrieved from an electronic database and caesarean delivery was divided into caesarean delivery for medical reasons and caesarean delivery for non-medical reasons. Physical activity and sleep status were collected at 24-28 weeks of gestation using self-reported questionnaires. Logistic regression and additive interaction were used to examine physical activity, sleep duration and their interactive effects on risk of caesarean delivery. RESULTS: In the cohort, 5692 (43.7%) and 2641 (20.3%) of women had caesarean delivery for medical reasons and non-medical reasons, respectively. Low physical activity increased the risk of caesarean delivery for medical reasons (adjusted OR: 1.13, 95%CI 1.04-1.23) but not caesarean delivery for non-medical reasons. Sleep duration < 7 h/day and poor sleep quality were not associated with caesarean delivery. Sleep duration ≥9 h/day increased the risk of caesarean delivery for medical reasons (1.12, 1.02-1.22) and caesarean delivery for non-medical reasons (1.16, 1.05-1.29). Co-presence of low physical activity and sleep duration ≥9 h/day increased risk of caesarean delivery (1.25, 1.12-1.41), and their additive interaction was statistically significant for caesarean delivery for medical reasons but not for caesarean delivery for non-medical reasons. CONCLUSIONS: Low physical activity and excessive sleep duration during pregnancy each increased the risk of caesarean delivery, and they had an interactive effect on the risk of caesarean delivery for medical reasons but not on the risk of caesarean delivery for non-medical reasons. Increasing physical activity and maintaining recommended sleep duration during pregnancy may have benefits for perinatal health.

Effects of rapid growth in early childhood on metabolic and cardiovascular diseases among preschool-aged children.

BACKGROUND AND OBJECTIVES: To investigate whether the tempo of weight gain of children during infancy (from birth up to two years of age) or childhood (between two and five years old) is associated with metabolic and cardiovascular disease. METHODS AND STUDY DESIGN: Cluster sampling was employed to obtain a random sample of preschool children. In total, 1450 children aged five to six years participated in this survey. We obtained data on body weight, height, blood pressure (BP), and serum levels of total cholesterol, triglycerides, glucose, and uric acid, as well as anthropometry at birth and at age 2. RESULTS: The prevalence of obesity at five years old was 14.5%. At five years of age, children with rapid growth (change in body mass index, BMI z-score >0.67) during infancy had a higher odds ratio (OR) of childhood obesity (OR: 2.97 [95% CI: 2.15-4.11]) compared to children with non-rapid growth (change in BMI z-score ≤0.67). Also, children with rapid growth during childhood had a higher OR of childhood obesity (OR: 17.90 [95% CI: 12.31-26.04]), higher systolic BP (OR: 2.38 [95% CI: 1.68-3.39]), higher diastolic BP (OR: 2.42 [95% CI: 1.53-3.83]), and higher triglycerides (OR: 4.09 [95% CI: 1.47-11.33]) or hyperuricemia (OR: 2.23 [95% CI: 1.51-3.29]). CONCLUSIONS: Rapid growth in early childhood is associated with risk factors for both cardiovascular outcomes and metabolic outcomes among preschool children. Developing effective prevention and intervention programs for pre-school children might be important to reduce incidence of long-term metabolic and cardiovascular disease as adults.

Nationwide population genetic screening improves outcomes of newborn screening for hearing loss in China.

PURPOSE: The benefits of concurrent newborn hearing and genetic screening have not been statistically proven due to limited sample sizes and outcome data. To fill this gap, we analyzed outcomes of newborns with genetic screening results. METHODS: Newborns in China were screened for 20 hearing-loss-related genetic variants from 2012 to 2017. Genetic results were categorized as positive, at-risk, inconclusive, or negative. Hearing screening results, risk factors, and up-to-date hearing status were followed up via phone interviews. RESULTS: Following up 12,778 of 1.2 million genetically screened newborns revealed a higher rate of hearing loss by three months of age among referrals from the initial hearing screening (60% vs. 5.0%, P < 0.001) and a lower rate of lost-to-follow-up/documentation (5% vs. 22%, P < 0.001) in the positive group than in the inconclusive group. Importantly, genetic screening detected 13% more hearing-impaired infants than hearing screening alone and identified 2,638 (0.23% of total) newborns predisposed to preventable ototoxicity undetectable by hearing screening. CONCLUSION: Incorporating genetic screening improves the effectiveness of newborn hearing screening programs by elucidating etiologies, discerning high-risk subgroups for vigilant management, identifying additional children who may benefit from early intervention, and informing at-risk newborns and their maternal relatives of increased susceptibility to ototoxicity.

Nomograms for incident risk of post-partum type 2 diabetes in Chinese women with prior gestational diabetes mellitus.

OBJECTIVE: Counselling patients with gestational diabetes mellitus (GDM) on their individual risk of post-partum type 2 diabetes (T2D) is challenging. This study aimed to develop nomograms for predicting incident risk of post-partum T2D in women with GDM diagnosed by WHO 1998 criteria. METHODS: We performed a retrospective cohort study in 1263 Chinese women with GDM, of whom 83 were diagnosed as T2D at 2.3 years post-partum. Multivariate Cox proportional hazards models were used to investigate the independent predictors for post-partum T2D. The results of multivariate analyses were used to formulate nomograms for predicting incident risk of post-partum T2D. The predictive accuracy was evaluated using the area under the receiver operating characteristic curve (AUROC). RESULTS: On multivariate analysis, independent predictors of post-partum T2DM in women with GDM included family history of diabetes [hazard ratio (HR) and its 95% confidential interval (95% CI): 2.06 (95% CI: 1.32-3.22)], history of pregnancy-induced hypertension [3.11 (95% CI: 1.86-5.21)], pre-pregnancy BMI [1.00, 1.90 (95% CI: 1.14-3.16), and 3.67 (95% CI: 2.03-6.63) for BMI <24, 24-28, and ≥28 kg/m2 ], and 2-hour glucose at 26-30 gestational weeks [1.00, 2.84 (95% CI: 1.42-5.69), and 9.42 (95% CI: 4.46-19.90) for 2-hour glucose at 7.8 ~ <8.5, 8.5 ~ <11.1, and ≥11.1 mmol/L). The overall AUROC of nomogram was 82.8% (95% CI: 78.1%-87.5%), with AUROCs of 85.9% (95% CI: 79.7%-92.1%) and 83.2% (95% CI: 77.9%-88.6%) for post-partum 2-year and 3-year risk of T2D, respectively. CONCLUSIONS: This easy-to-use nomogram, with non-invasive clinical characteristics, can accurately predict the risk of post-partum T2D in women with GDM. It may facilitate risk communication between patients and clinicians.

Lactation intensity and duration to postpartum diabetes and prediabetes risk in women with gestational diabetes.

OBJECTIVE: To investigate the association of lactation intensity and duration with postpartum diabetes and prediabetes risks among Chinese women with a history of gestational diabetes (GDM). METHODS: We included 1260 women with a history of GDM who participated in the whole population's GDM universal screening survey by using the 1999 World Health Organization's criteria. Lactation intensity and lactation duration were collected by a standardized questionnaire. Postpartum diabetes and prediabetes risk were confirmed by an oral glucose tolerance test. RESULTS: During a mean postpartum period of 3.65 years, we identified 114 cases of diabetes and 417 cases of prediabetes. The multivariable-adjusted hazard ratios based on different lactation intensity (exclusive formula, mixed feeding, and exclusive lactation) were 1.00, 0.68, 0.45 for diabetes (Ptrend  = 0.008), and 1.00, 0.74, and 0.61 for prediabetes (Ptrend  = 0.006), respectively. The multivariable-adjusted hazard ratios associated with different lactation duration (none, 0-6 months, 6-12 months, 12-18 months, and ≥18 months) were 1.00, 0.66, 0.42, 0.66, and 0.25 for diabetes (Ptrend  = 0.013), and 1.00, 0.82, 0.62, 0.67, and 0.63 for prediabetes (Ptrend  = 0.021), respectively. A restricted cubic spline curve showed a graded inverse association of lactation duration with the risks of diabetes and prediabetes (Ptrend  < 0.001). CONCLUSIONS: Higher-lactation intensity and longer-lactation duration were significantly associated with lower risks of postpartum diabetes and prediabetes among Chinese women with a history of GDM.

Passive smoking and postpartum depression among Chinese women: A prospective cohort study in Tianjin, China.

Smoking has been associated with depression in the general population. Whether passive smoking is also associated with postpartum depression (PPD) is uncertain. From 2010 to 2012, we recruited 8,842 pregnant women in Tianjin, China. The mainland Chinese version of the Edinburgh Postnatal Depression Scale was used to evaluate postpartum depressive symptoms after birth, with a score of >9 defining PPD. Data were collected using specially designed questionnaires or data from the electronic database of Tianjin Maternal and Child Health Information System. Odds ratios (OR) and 95 percent confidence intervals (CI) were obtained for the association of smoking status with PPD using binary logistic regression. Passive smoke exposure rates before and during pregnancy were 40.9 percent and 52.1 percent, respectively. A total of 8.5% (n = 747) of participants had PPD. Compared with those not exposed, women passively exposed to smoke before and during pregnancy had higher odds of PPD (before pregnancy: OR: 1.24, 95 percent CI: 1.03-1.50; during pregnancy: OR: 1.43, 95 percent CI: 1.16-1.77) after adjustment for confounding factors. Passive smoking before and during pregnancy were associated with PPD in Chinese women. Reducing passive smoke exposure may reduce PPD in Chinese women; further longitudinal studies are warranted to replicate these findings.

One-year weight losses in the Tianjin Gestational Diabetes Mellitus Prevention Programme: A randomized clinical trial.

AIMS: To report the weight loss findings after the first year of a lifestyle intervention trial among women with gestational diabetes mellitus (GDM). METHODS: A total of 1180 women with GDM were randomly assigned (1:1) to receive a 4-year lifestyle intervention (intervention group, n = 586) or standard care (control group, n = 594) between August 2009 and July 2011. Major elements of the intervention included 6 face-to-face sessions with study dieticians and two telephone calls in the first year, and two individual sessions and two telephone calls in each subsequent year. RESULTS: Among 79% of participants who completed the year 1 trial, mean weight loss was 0.82 kg (1.12% of initial weight) in the intervention group and 0.09 kg (0.03% of initial weight) in the control group (P = .001). In a prespecified subgroup analysis of people who completed the trial, weight loss was more pronounced in women who were overweight (body mass index ≥24 kg/m2 ) at baseline: mean weight loss 2.01 kg (2.87% of initial weight) in the intervention group and 0.44 kg (0.52% of initial weight) in the control group (P < .001). Compared with those in the control group, women in the intervention group had a greater decrease in waist circumference (1.76 cm vs 0.73 cm; P = .003) and body fat (0.50% vs 0.05% increase; P = .001). CONCLUSION: The 1-year lifestyle intervention led to significant weight losses after delivery in women who had GDM, and the effect was more pronounced in women who were overweight at baseline.

Effects of the interaction between glycated haemoglobin genetic risk score and postpartum weight reduction on glycaemic changes: A gene-weight interaction analysis.

AIM: To investigate the effects of the interaction between glycated haemoglobin (HbA1c) genetic risk score and weight changes during and after pregnancy (postpartum weight reduction and gestational weight gain) on long-term glycaemic changes in the largest cohort of women with a history of gestational diabetes mellitus (GDM). METHODS: This was a retrospective cohort using the baseline data from the Tianjin Gestational Diabetes Mellitus Prevention Programme. A genetic risk score was established by combining 10 HbA1c-related single-nucleotide polymorphisms, which were identified by genome-wide association studies. General linear regression models were applied to evaluate the effect of interaction between HbA1c genetic risk score and weight changes during and after pregnancy (postpartum weight reduction and gestational weight gain) on glycaemic changes. RESULTS: 'A total of 1156 women with a history of GDM were included in this respective cohort study. Statistical differences in pre-pregnancy weight, pre-delivery weight and postpartum weight were evidenced across different groups of postpartum weight reduction. After adjusting for covariates, statistical significance for changes in HbA1c level was only observed in the postpartum weight reduction <5 kg/y group (P = 0.002), and a significant effect of interaction between HbA1c genetic risk score and postpartum weight reduction on long-term changes in HbA1c was evidenced (P interaction = 0.01). In women with postpartum weight reduction ≥8 kg/y, those with a lower HbA1c genetic risk score had a greater decrease in HbA1c level. CONCLUSIONS: HbA1c genetic risk score interacts with postpartum weight reduction to affect long-term changes in HbA1c levels among women with a history of GDM.

ABO blood types and postpartum depression among Chinese women: A prospective cohort study in Tianjin, China.

Postpartum depression is associated with adverse consequences for mother and offspring. The heritable ABO blood group has been associated with multiple diseases, including mental illness and diabetes. We explored the association of ABO blood group and postpartum depressive symptoms (PPDS) in a population-based cohort of pregnant Chinese women. From 2010 to August 2012, we recruited 8842 pregnant women with a mean age of 28.5 years (SD: 2.94) and mean body mass index of 22.4kg/m2 (SD: 3.45) in Tianjin, China. We used the Mainland Chinese version of the Edinburgh Postnatal Depression Scale after delivery with a cutoff score of 10 to define PPDS. Odds ratios (ORs) and 95% confidence intervals (CIs) for PPDS were obtained using binary logistic regression. Of 8842 women, 8.5% (n = 747) developed PPDS. Compared to those with blood group B, women with blood groups A, AB or O had a higher odds of PPDS (adjusted ORs: 1.23 (95% CI: 1.13-1.40), 1.31 (95% CI: 0.98-1.74), and 1.30(95% CI:1.03-1.60), respectively). Blood group B was associated with reduced odds of PPDS in pregnant Chinese women. If replicated in other studies, non-blood group B may be a useful risk factors for PPDS in Chinese pregnant women.