Gestational diabetes mellitus in Africa: a systematic review.

BACKGROUND: Gestational diabetes mellitus (GDM) is any degree of impaired glucose tolerance first recognised during pregnancy. Most women with GDM revert to normal glucose metabolism after delivery of their babies; however, they are at risk of developing type 2 diabetes later in life as are their offspring. Determining a country's GDM prevalence can assist with policy guidelines regarding GDM screening and management, and can highlight areas requiring research. This systematic review assesses GDM prevalence in Africa. METHODS AND FINDINGS: Three electronic databases were searched without language restrictions; PubMed, Scopus and the Cochrane Library. Thirty-one search terms were searched. Eligible articles defined GDM, stated what GDM screening approaches were employed and reported GDM prevalence. The reporting quality and risk of bias within each study was assessed. The PRISMA guidelines for systematic reviews were followed. The literature search identified 466 unique records. Sixty full text articles were reviewed of which 14 were included in the systematic review. One abstract, for which the full text article could not be obtained, was also included. Information regarding GDM classification, screening methods and prevalence was obtained for six African countries; Ethiopia (n = 1), Morocco (n = 1), Mozambique (n = 1), Nigeria (n = 6), South Africa (n= 4) and Tanzania (n = 1). Prevalence figures ranged from 0% (Tanzania) to 13.9% (Nigeria) with some studies focussing on women with GDM risk factors. Most studies utilised the two hour 75 g oral glucose tolerance test and applied the World Health Organization's diagnostic criteria. CONCLUSIONS: Six countries, equating to 11% of the African continent, were represented in this systematic review. This indicates how little is known about GDM in Africa and highlights the need for further research. Considering the increasing public health burden of obesity and type 2 diabetes, it is essential that the extent of GDM is understood in Africa to allow for effective intervention programmes.This is the final published version of the article. It was originally published here: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0097871

Abdominal fat depots associated with insulin resistance and metabolic syndrome risk factors in black African young adults

Abstract Background Individuals of black African ethnicity tend to have less visceral adipose tissue (VAT) but more subcutaneous-abdominal adipose tissue (SCAT) than white Caucasians. However, it is unclear whether such distribution of abdominal fat is beneficial for metabolic disease risk in black individuals. Here we compared the associations between these specific abdominal fat depots, insulin sensitivity and metabolic syndrome risk. Methods A cross-sectional analysis of 76 black South African young adults (36 men; 40 women) aged 18–19 years participating in the Birth to Twenty Cohort Study had VAT and SCAT measured by MRI. The metabolic syndrome traits (blood pressure, lipid profile, fasting glucose and insulin) were measured and the values were combined into a metabolic syndrome risk score. Fasting glucose and insulin were used to derive the HOMA-index of insulin resistance (HOMA-IR). Results Compared to men, women had greater VAT (mean: 16.6 vs. 12.5 cm2) and SCAT (median 164.0 vs. 59.9 cm2). In men, SCAT (r = 0.50) was more strongly correlated to the metabolic syndrome score (MetS) than was VAT (r = 0.23), and was associated with both MetS (P = 0.001) and HOMA-IR (P = 0.001) after adjustment for VAT and total fat mass. In women, both abdominal fat compartments showed comparable positive correlations with MetS (r = 0.26 to 0.31), although these trends were weaker than in men. Conclusions In young black South African adults, SCAT appears to be more relevant than VAT to metabolic syndrome traits

The association between age at menarche and later risk of gestational diabetes is mediated by insulin resistance.

AIMS: Associations have been reported between age at menarche and the later risk of gestational diabetes. However, it is not known whether these associations reflect differences in insulin sensitivity and/or pancreatic β-cell function in pregnancy. METHODS: We examined this question in women enrolled in the prospective Cambridge Baby Growth Study who recalled their age at menarche in questionnaires during pregnancy. Polynomial logistic and linear regression models were used to relate menarche timing to the risk of gestational diabetes, both unadjusted and adjusted for the Homeostasis Model Assessments of insulin resistance (HOMA IR) and pancreatic β-cell function (HOMA B) at week 28 of pregnancy. RESULTS: Age at menarche showed a U-shaped association with gestational diabetes risk (linear term: p = 9.5 × 10-4; quadratic term: p = 1.0 × 10-3; n = 889; overall model p = 8.1 × 10-3). Age at menarche showed a negative linear association with insulin resistance (HOMA IR: β = -0.13, p = 5.2 × 10-4, n = 771), which explained the relationship between age at menarche and gestational diabetes risk (adjusted linear term going from p = 0.03-0.08; adjusted quadratic term going from p = 0.04-0.08; n = 771). Age at menarche also showed a negative linear association with β-cell function (HOMA B: β = -0.11, p = 2.8 × 10-3, n = 771) but this did not attenuate the relationship between age at menarche and gestational diabetes (adjusted linear term p = 0.02; adjusted quadratic term p = 0.03, n = 771). CONCLUSIONS: These results suggest that the associations between age at menarche and risk of gestational diabetes and raised pregnancy glucose concentrations may be mediated by insulin resistance.Funding for this study has come from the Wellbeing of Women (the Royal College of Obstetricians and Gynaecologists, UK) (RG1644). Other core funding has come from the Medical Research Council (7500001180, G1001995, U106179472), European Union Framework 5 (QLK4-1999-01422), the Mothercare Charitable Foundation (RG54608), Newlife Foundation for Disabled Children (07/20), and the World Cancer Research Fund International (2004/03). In addition, there has been support from National Institute for Health Research Cambridge Biomedical Research Centre. KO is supported by the Medical Research Council (Unit Programme number: MC_UU_12015/2)

Nutritional status and HIV in rural South African children.

BACKGROUND: Achieving the Millennium Development Goals that aim to reduce malnutrition and child mortality depends in part on the ability of governments/policymakers to address nutritional status of children in general and those infected or affected by HIV/AIDS in particular. This study describes HIV prevalence in children, patterns of malnutrition by HIV status and determinants of nutritional status. METHODS: The study involved 671 children aged 12-59 months living in the Agincourt sub-district, rural South Africa in 2007. Anthropometric measurements were taken and HIV testing with disclosure was done using two rapid tests. Z-scores were generated using WHO 2006 standards as indicators of nutritional status. Linear and logistic regression analyses were conducted to establish the determinants of child nutritional status. RESULTS: Prevalence of malnutrition, particularly stunting (18%), was high in the overall sample of children. HIV prevalence in this age group was 4.4% (95% CI: 2.79 to 5.97). HIV positive children had significantly poorer nutritional outcomes than their HIV negative counterparts. Besides HIV status, other significant determinants of nutritional outcomes included age of the child, birth weight, maternal age, age of household head, and area of residence. CONCLUSIONS: This study documents poor nutritional status among children aged 12-59 months in rural South Africa. HIV is an independent modifiable risk factor for poor nutritional outcomes and makes a significant contribution to nutritional outcomes at the individual level. Early paediatric HIV testing of exposed or at risk children, followed by appropriate health care for infected children, may improve their nutritional status and survival.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

Serum Phthalate and Triclosan Levels Have Opposing Associations With Risk Factors for Gestational Diabetes Mellitus.

Certain phthalates and bisphenol A (BPA) have been associated with insulin resistance and type 2 diabetes in non-pregnant adults, but studies of gestational diabetes mellitus (GDM) have reported conflicting results for phthalates and no associations with BPA. Our aim was to investigate the relationship between maternal serum levels of phthalate metabolites and phenols at 10-17 weeks of gestation and glucose homeostasis at 28 weeks of gestation. 232 women aged ≥16 years without type 1 or 2 diabetes with singleton male pregnancies were recruited from a single UK maternity centre between 2001 and 2009 as part of a prospective observational study (Cambridge Baby Growth Study). Serum levels of 16 phthalate metabolites and 9 phenols (including BPA) were measured using liquid chromatography/tandem mass spectrometry. Oral glucose tolerance tests were performed at 28 weeks. 47/232 (20.3%) women had GDM. First-trimester triclosan (TCS) was inversely associated with incident GDM (adjusted odds ratio per log increase in concentration 0.54, 95% confidence interval 0.34-0.86, p = 0.010). Amongst women without GDM, first-trimester mono-(2-ethylhexyl) phthalate and mono(carboxyisooctyl) phthalate levels were positively associated with 120-min plasma glucose (adjusted β 0.268 and 0.183, p = 0.0002 and 0.010, respectively) in mid-pregnancy. No other monotonic associations were detected between phthalate or phenol levels and fasting or stimulated plasma glucose, β-cell function, insulin resistance, or 60-min disposition index. Our results support a glycaemia-raising effect of phthalates during pregnancy, consistent with findings in non-pregnant populations and suggest a possible protective effect of exposure to TCS against GDM

Genetic markers of insulin sensitivity and insulin secretion are associated with spontaneous postnatal growth and response to growth hormone treatment in short SGA children: the North European SGA Study (NESGAS).

PURPOSE: The wide heterogeneity in the early growth and metabolism of children born small for gestational age (SGA), both before and during GH therapy, may reflect common genetic variations related to insulin secretion or sensitivity. METHOD: Combined multiallele single nucleotide polymorphism scores with known associations with insulin sensitivity or insulin secretion were analyzed for their relationships with spontaneous postnatal growth and first-year responses to GH therapy in 96 short SGA children. RESULTS: The insulin sensitivity allele score (GS-InSens) was positively associated with spontaneous postnatal weight gain (regression coefficient [B]: 0.12 SD scores per allele; 95% confidence interval [CI], 0.01-0.23; P = .03) and also in response to GH therapy with first-year height velocity (B: 0.18 cm/y per allele; 95% CI, 0.02-0.35; P = .03) and change in IGF-1 (B: 0.17 SD scores per allele; 95% CI, 0.00-0.32; P = .03). The association with first-year height velocity was independent of reported predictors of response to GH therapy (adjusted P = .04). The insulin secretion allele score (GS-InSec) was positively associated with spontaneous postnatal height gain (B: 0.15; 95% CI, 0.01-0.30; P = .03) and disposition index both before (B: 0.02; 95% CI, 0.00-0.04; P = .04) and after 1 year of GH therapy (B: 0.03; 95% CI, 0.01-0.05; P = .002), but not with growth and IGF-1 responses to GH therapy. Neither of the allele scores was associated with size at birth. CONCLUSION: Genetic allele scores indicative of insulin sensitivity and insulin secretion were associated with spontaneous postnatal growth and responses to GH therapy in short SGA children. Further pharmacogenetic studies may support the rationale for adjuvant therapies by informing the mechanisms of treatment response.This study was funded by a research grant from The Danish Council for Independent Research/ Medical Sciences and a research grant from Novo Nordisk A/S.This is the accepted manuscript. The final version is available at http://dx.doi.org/10.1210/jc.2014-3469

Breast milk nutrient content and infancy growth.

AIM: Benefits of human breast milk (HM) in avoiding rapid infancy weight gain and later obesity could relate to its nutrient content. We tested the hypothesis that differential HM total calorie content (TCC) or macronutrient contents may be associated with infancy growth. METHODS: HM hindmilk samples were collected at ages 4-8 weeks from 614 mothers participating in a representative birth cohort, with repeated infancy anthropometry. HM triglyceride (fat), lipid analytes and lactose (carbohydrate) were measured by (1) H-NMR, and protein content by the Dumas method. TCC and %macronutrients were determined. RESULTS: In 614 HM samples, fat content was as follows: [median(IQR)]: 2.6 (1.7-3.6) g/100 mL, carbohydrate: 8.6 (8.2-8.8) g/100 mL, protein: 1.2 (1.1-1.2) g/100 mL; TCC: 61.8 (53.7-71.3) kcal/100 mL. HM of mothers exclusively breast feeding vs. mixed feeding was more calorific with higher %fat, lower %carbohydrate and lower %protein. Higher HM TCC was associated with lower 12-months body mass index (BMI)/adiposity, and lower 3-12 months gains in weight/BMI. HM %fat was inversely related to 3-12 months gains in weight, BMI and adiposity, whereas %carbohydrate was positively related to these measures. HM %protein was positively related to 12-months BMI. CONCLUSION: HM analysis showed wide variation in %macronutrients. Although data on milk intakes were unavailable, our findings suggest functional relevance of HM milk composition to infant growth.PP was supported by a MRC Clinical Training Fellowship (G1001995). The Cambridge Baby Growth Study has been supported by the European Union, the World Cancer Research Foundation International, the Medical Research Council, the NIHR Cambridge Comprehensive Biomedical Research Centre, the Newlife Foundation for disabled children, the Mothercare Group Foundation, and Mead Johnson Nutrition.This is the final version of the article. It first appeared from Wiley via https://doi.org/ 10.1111/apa.1336

Common polymorphism in H19 associated with birthweight and cord blood IGF-II levels in humans.

BACKGROUND: Common genetic variation at genes that are imprinted and exclusively maternally expressed could explain the apparent maternal-specific inheritance of low birthweight reported in large family pedigrees. We identified ten single nucleotide polymorphisms (SNPs) in H19, and we genotyped three of these SNPs in families from the contemporary ALSPAC UK birth cohort (1,696 children, 822 mothers and 661 fathers) in order to explore associations with size at birth and cord blood IGF-II levels. RESULTS: Both offspring's and mother's H19 2992C>T SNP genotypes showed associations with offspring birthweight (P = 0.03 to P = 0.003) and mother's genotype was also associated with cord blood IGF-II levels (P = 0.0003 to P = 0.0001). The offspring genotype association with birthweight was independent of mother's genotype (P = 0.01 to P = 0.007). However, mother's untransmitted H19 2992T allele was also associated with larger birthweight (P = 0.04) and higher cord blood IGF-II levels (P = 0.002), suggesting a direct effect of mother's genotype on placental IGF-II expression and fetal growth. The association between mother's untransmitted allele and cord blood IGF-II levels was more apparent in offspring of first pregnancies than subsequent pregnancies (P-interaction = 0.03). Study of the independent Cambridge birth cohort with available DNA in mothers (N = 646) provided additional support for mother's H19 2992 genotype associations with birthweight (P = 0.04) and with mother's glucose levels (P = 0.01) in first pregnancies. CONCLUSION: The common H19 2992T allele, in the mother or offspring or both, may confer reduced fetal growth restraint, as indicated by associations with larger offspring birth size, higher cord blood IGF-II levels, and lower compensatory early postnatal catch-up weight gain, that are more evident among mother's smaller first-born infants.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

An Unbiased Lipidomics Approach Identifies Early Second Trimester Lipids Predictive of Maternal Glycemic Traits and Gestational Diabetes Mellitus.

OBJECTIVE: To investigate the relationship between early second trimester serum lipidomic variation and maternal glycemic traits at 28 weeks and to identify predictive lipid biomarkers for gestational diabetes mellitus (GDM). RESEARCH DESIGN AND METHODS: Prospective study of 817 pregnant women (discovery cohort, n = 200; validation cohort, n = 617) who provided an early second trimester serum sample and underwent an oral glucose tolerance test (OGTT) at 28 weeks. In the discovery cohort, lipids were measured using direct infusion mass spectrometry and correlated with OGTT results. Variable importance in projection (VIP) scores were used to identify candidate lipid biomarkers. Candidate biomarkers were measured in the validation cohort using liquid chromatography-mass spectrometry and tested for associations with OGTT results and GDM status. RESULTS: Early second trimester lipidomic variation was associated with 1-h postload glucose levels but not with fasting plasma glucose levels. Of the 13 lipid species identified by VIP scores, 10 had nominally significant associations with postload glucose levels. In the validation cohort, 5 of these 10 lipids had significant associations with postload glucose levels that were independent of maternal age and BMI, i.e., TG(51.1), TG(48:1), PC(32:1), PCae(40:3), and PCae(40:4). All except the last were also associated with maternal GDM status. Together, these four lipid biomarkers had moderate ability to predict GDM (area under curve [AUC] = 0.71 ± 0.04, P = 4.85 × 10-7) and improved the prediction of GDM by age and BMI alone from AUC 0.69 to AUC 0.74. CONCLUSIONS: Specific early second trimester lipid biomarkers can predict maternal GDM status independent of maternal age and BMI, potentially enhancing risk factor-based screening.This part of the Cambridge Baby Growth Study was funded by grants from the Wellbeing of Women (RG1644) and Diabetes UK (11/0004241). The lipidomics assays were supported by the Medical Research Council (UD99999906) and Cambridge Lipidomics Biomarker Research Initiative (G0800783). Core funding was also obtained through the Medical Research Council, European Union Framework 5 World Cancer Research Fund, Mothercare Foundation and the Newlife Foundation for Disabled Children. There has also been support from National Institute for Health Research Cambridge Biomedical Research Centre.This is the author accepted manuscript. The final version is available from the American Diabetes Association via https://doi.org/10.2337/dc16-086

Understanding the Relationship between Socio-Economic Status, Physical Activity and Sedentary Behaviour, and Adiposity in Young Adult South African Women Using Structural Equation Modelling.

Socio-economic status (SES) is an important predictor of obesity, but how it is associated with differences in physical activity and sedentary behaviour is less clear. This cross-sectional study examined the association between SES (sum of household assets), physical activity and sedentary time, and how they predict adiposity. Socio-demographic, anthropometric, and physical activity data on rural (n = 509) and urban (n = 510) South African women (18-23 years) were collected. Overweight and obesity prevalence, and sedentary time, were higher; and moderate-vigorous intensity physical activity (MVPA) was lower, in the urban sample. Structural equation models (SEMs) were constructed for BMI and waist circumference. In the urban sample SES had a direct inverse effect on MVPA (ß; 95% CI, -41.69; -73.40 to -9.98), while in the rural sample SES had a direct effect on BMI (ß; 95% CI, 0.306; 0.03 to 0.59). In the pooled sample, SES had a direct inverse effect on MVPA (ß; 95% CI, -144; -170.34 to -119.04), and MVPA was directly associated with BMI (ß; 95% CI, 0.04; 0.01 to 0.08). The influence of SES, and the role of physical activity and sedentary time on adiposity differs between the urban and rural samples, and the importance of other environmental and behavioural factors must be considered in the development of obesity and the design of effective interventions