Helen L. Barrett

Vitamin D and pregnancy: An old problem revisited

Vitamin D has historically been considered to play a role solely in bone and calcium metabolism. Human disease associations and basic physiological studies suggest that vitamin D deficiency is plausibly implicated in adverse health outcomes including mortality, malignancy, cardiovascular disease, immune functioning and glucose metabolism. There is considerable evidence that low maternal levels of 25 hydroxyvitamin D are associated with adverse outcomes for both mother and fetus in pregnancy as well as the neonate and child. Vitamin D deficiency during pregnancy has been linked with a number of maternal problems including infertility, preeclampsia, gestational diabetes and an increased rate of caesarean section. Likewise, for the child, there is an association with small size, impaired growth and skeletal problems in infancy, neonatal hypocalcaemia and seizures, and an increased risk of HIV transmission. Other childhood disease associations include type 1 diabetes and effects on immune tolerance. The optimal concentration of 25 hydroxyvitamin D is unknown and compounded by difficulties in defining the normal range. Whilst there is suggestive physiological evidence to support a causal role for many of the associations, whether vitamin D deficiency is a marker of poor health or the underlying aetiological problem is unclear. Randomised controlled trials of vitamin D supplementation with an appropriate assessment of a variety of health outcomes are required.

Pain characteristics in patients admitted to hospital with complications after spinal cord injury.

OBJECTIVES To determine characteristics of pain, the relation between pain and mood, the effect of pain on activities, and the perceived difficulty in coping with pain in patients hospitalized for treatment of complications associated with spinal cord injury (SCI). DESIGN Cohort survey. SETTING Hospital inpatient unit in Australia. PARTICIPANTS Consecutive sample of patients (N=88) admitted to a hospital spinal injuries unit with complications after SCI. Two eligible patients declined to participate. INTERVENTION Face-to-face interview with questionnaire. MAIN OUTCOME MEASURES Pain severity, global self-rated health, mood (Kessler Mood Inventory), and interference with activities (Von Korff disability scale). RESULTS Sixty-six (75%) of the 88 subjects experienced pain, with an average time of onset +/- standard deviation of 8.02+/-12.4 years; 27% of those with pain described it as severe or excruciating. Subjects with pain were less likely to rate their global health as excellent or very good when compared with those who did not have pain (22% vs 44%, respectively). Patients with pain had significantly greater levels of psychologic distress than did people with SCI and no pain. CONCLUSIONS Pain is a common problem in people admitted to hospital with SCI for treatment of other complications. It has a significant impact on activities and is associated with a reduction in global self-rated health and higher levels of psychologic distress.

SPRING: an RCT study of probiotics in the prevention of gestational diabetes mellitus in overweight and obese women

BackgroundObesity is increasing in the child-bearing population as are the rates of gestational diabetes. Gestational diabetes is associated with higher rates of Cesarean Section for the mother and increased risks of macrosomia, higher body fat mass, respiratory distress and hypoglycemia for the infant. Prevention of gestational diabetes through life style intervention has proven to be difficult. A Finnish study showed that ingestion of specific probiotics altered the composition of the gut microbiome and thereby metabolism from early gestation and decreased rates of gestational diabetes in normal weight women. In SPRING (the Study of Probiotics IN the prevention of Gestational diabetes), the effectiveness of probiotics ingestion for the prevention of gestational diabetes will be assessed in overweight and obese women.Methods/designSPRING is a multi-center, prospective, double-blind randomized controlled trial run at two tertiary maternity hospitals in Brisbane, Australia. Five hundred and forty (540) women with a BMI > 25.0 kg/m2 will be recruited over 2 years and receive either probiotics or placebo capsules from 16 weeks gestation until delivery. The probiotics capsules contain > 1x109 cfu each of Lactobacillus rhamnosus GG and Bifidobacterium lactis BB-12 per capsule. The primary outcome is diagnosis of gestational diabetes at 28 weeks gestation. Secondary outcomes include rates of other pregnancy complications, gestational weight gain, mode of delivery, change in gut microbiome, preterm birth, macrosomia, and infant body composition. The trial has 80% power at a 5% 2-sided significance level to detect a >50% change in the rates of gestational diabetes in this high-risk group of pregnant women.DiscussionSPRING will show if probiotics can be used as an easily implementable method of preventing gestational diabetes in the high-risk group of overweight and obese pregnant women.

Normalizing metabolism in diabetic pregnancy: Is it time to target lipids?

Outcomes in pregnancies complicated by preexisting diabetes (type 1 and type 2) and gestational diabetes mellitus have improved, but there is still excess morbidity compared with normal pregnancy. Management strategies appropriately focus on maternal glycemia, which demonstrably improves pregnancy outcomes for mother and infant. However, we may be reaching the boundaries of obtainable glycemic control for many women. It has been acknowledged that maternal lipids are important in pregnancies complicated by diabetes. Elevated maternal lipids are associated with preeclampsia, preterm delivery, and large-for-gestational-age infants. Despite this understanding, assessment of management strategies targeting maternal lipids has been neglected to date. Consideration needs to be given to whether normalizing maternal lipids would further improve pregnancy outcomes. This review examines the dyslipidemia associated with pregnancy complicated by diabetes, reviews possible therapies, and considers whether it is time to start actively managing this aspect of maternal metabolism.

Increased Systolic and Diastolic Blood Pressure Is Associated With Altered Gut Microbiota Composition and Butyrate Production in Early Pregnancy

The risk of developing pregnancy-induced hypertension and preeclampsia is higher in obese pregnant women. In obesity, the composition of the gut microbiota is altered. Obesity is also associated with low-grade inflammation. Metabolites from the gut microbiota may contribute to both hypertension and inflammation. The aim of this study is to investigate whether the composition of the gut microbiota in overweight and obese pregnant women is associated with blood pressure and levels of plasminogen activator inhibitor-1. The composition of the gut microbiota was determined with 16S ribosomal RNA sequencing in 205 women at 16 weeks gestation from the SPRING study (the Study of Probiotics in Gestational Diabetes). Expression of butyrate-producing genes in the gut microbiota was assessed by real-time polymerase chain reaction. Plasminogen activator inhibitor-1 levels were measured in fasting serum of a subset of 70 women. Blood pressure was slightly but significantly higher in obese compared with overweight women. The abundance of the butyrate-producing genus Odoribacter was inversely correlated with systolic blood pressure. Butyrate production capacity was decreased, but plasminogen activator inhibitor-1 concentrations increased in obese pregnant women. Plasminogen activator inhibitor-1 levels were inversely correlated with expression of butyrate kinase and Odoribacter abundance. This study shows that in overweight and obese pregnant women at 16 weeks gestation, the abundance of butyrate-producing bacteria and butyrate production in the gut microbiota is significantly negatively associated with blood pressure and with plasminogen activator inhibitor-1 levels. Increasing butyrate-producing capacity may contribute to maintenance of normal blood pressure in obese pregnant women.

Watchful waiting: A management protocol for maternal glycaemia in the peripartum period

Background: It is accepted that tight glycaemic control is necessary during labour in women with pregestational or gestational diabetes mellitus (GDM). Although policies vary, routine use of intravenous glucose and insulin remains a standard practice in some institutions. We present a retrospective review of a more conservative approach. Briefly, regardless of planned delivery method, maternal blood sugar level (BSL) is monitored during delivery and only if outside 4–7 mmol/L is action taken. We report the results of an audit of this practice.

Maternal and Neonatal Circulating Markers of Metabolic and Cardiovascular Risk in the Metformin in Gestational Diabetes (MiG) Trial: Responses to maternal metformin versus insulin treatment

OBJECTIVE This study was designed to compare glucose, lipids, and C-reactive protein (CRP) in women with gestational diabetes mellitus treated with metformin or insulin and in cord plasma of their offspring and to examine how these markers relate to infant size at birth. RESEARCH DESIGN AND METHODS Women with gestational diabetes mellitus were randomly assigned to metformin or insulin in the Metformin in Gestational Diabetes trial. Fasting maternal plasma glucose, lipids, and CRP were measured at randomization, 36 weeks’ gestation, and 6–8 weeks postpartum as well as in cord plasma. Women with available cord blood samples (metformin n = 236, insulin n = 242) were included. RESULTS Maternal plasma triglycerides increased more from randomization to 36 weeks’ gestation in women treated with metformin (21.93%) versus insulin (9.69%, P < 0.001). Maternal and cord plasma lipids, CRP, and neonatal anthropometry did not differ between treatments. In logistic regression analyses adjusted for confounders, the strongest associations with birth weight >90th centile were maternal triglycerides and measures of glucose control at 36 weeks. CONCLUSIONS There were few differences in circulating maternal and neonatal markers of metabolic status and no differences in measures of anthropometry between the offspring of women treated with metformin and the offspring of women treated with insulin. There may be subtle effects of metformin on maternal lipid function, but the findings suggest that treating gestational diabetes mellitus with metformin does not adversely affect lipids or CRP in cord plasma or neonatal anthropometric measures.

Exercise in pregnancy does not alter gestational weight gain, MCP‐1 or leptin in obese women

Increasing physical activity in pregnancy may improve pregnancy outcomes for obese women. Exercise could reduce gestational weight gain, improve the maternal circulating lipid profile as well as alter leptin, Interleukin‐8 (IL‐8) and Monocyte Chemoattractant Protein‐1 (MCP‐1) levels.

Determinants of Maternal Triglycerides in Women With Gestational Diabetes Mellitus in the Metformin in Gestational Diabetes (MiG) Study

OBJECTIVE Factors associated with increasing maternal triglyceride concentrations in late pregnancy include gestational age, obesity, preeclampsia, and altered glucose metabolism. In a subgroup of women in the Metformin in Gestational Diabetes (MiG) trial, maternal plasma triglycerides increased more between enrollment (30 weeks) and 36 weeks in those treated with metformin compared with insulin. The aim of this study was to explain this finding by examining factors potentially related to triglycerides in these women. RESEARCH DESIGN AND METHODS Of the 733 women randomized to metformin or insulin in the MiG trial, 432 (219 metformin and 213 insulin) had fasting plasma triglycerides measured at enrollment and at 36 weeks. Factors associated with maternal triglycerides were assessed using general linear modeling. RESULTS Mean plasma triglyceride concentrations were 2.43 (95% CI 2.35–2.51) mmol/L at enrollment. Triglycerides were higher at 36 weeks in women randomized to metformin (2.94 [2.80–3.08] mmol/L; +23.13% [18.72–27.53%]) than insulin (2.65 [2.54–2.77] mmol/L, P = 0.002; +14.36% [10.91–17.82%], P = 0.002). At 36 weeks, triglycerides were associated with HbA1c (P = 0.03), ethnicity (P = 0.001), and treatment allocation (P = 0.005). In insulin-treated women, 36-week triglycerides were associated with 36-week HbA1c (P = 0.02), and in metformin-treated women, they were related to ethnicity. CONCLUSIONS At 36 weeks, maternal triglycerides were related to glucose control in women treated with insulin and ethnicity in women treated with metformin. Whether there are ethnicity-related dietary changes or differences in metformin response that alter the relationship between glucose control and triglycerides requires further study.

Increased Placental Expression of Fibroblast Growth Factor 21 in Gestational Diabetes Mellitus

BACKGROUND Fibroblast growth factor 21 (FGF21) can regulate glucose and lipid metabolism. The placenta actively synthesizes and secretes many hormones, but it is unknown whether this includes FGF21. This study aimed to analyze the placental expression of FGF21 in women with or without gestational diabetes mellitus (GDM). METHODS FGF21 and peroxisome proliferator-activated receptor (PPAR)-α mRNA and protein expression were measured in the placentae of 20 women with and 18 without GDM. mRNA expression of PPARα, FGF receptors 1-4, the coreceptor β-klotho, and glucose transporter (GLUT)-1, -3, and -4 was investigated. Maternal and fetal circulating FGF21 levels were assessed in 10 mother-baby dyads per condition. RESULTS FGF21 was expressed in the placenta and its mRNA expression increased in women with GDM [10.75 (interquartile range 3.28-125.6 AU)] vs control [0.83 (0.22-4.78), P < .001], as is its protein expression [GDM 2.89 (1.44-5.10)] vs control [0.42 (0.05-1.98), P < .05]. PPARα mRNA but not protein expression was increased in GDM [2.94 (0.70-7.26)] vs control [0.99 (0.43-2.17), P < .05] and was positively correlated to FGF21 mRNA expression (ρ = 0.43, P < .01). Placental mRNA expression of FGF receptors and GLUT1 was unchanged, and β-klotho, GLUT3, and GLUT4 showed increased expression in GDM. Maternal circulating FGF21 levels were similar [GDM 323 (75-921) vs control 269 (49-731) pg/mL, P = .81]. FGF21 was undetected in fetal cord blood. CONCLUSIONS FGF21 is expressed in the placenta and its expression is increased in GDM. The absence of FGF21 in fetal cord blood suggests that neither placental FGF21 nor maternal circulating FGF21 is secreted into the fetal circulation. Placental FGF21 may be a regulator of placental metabolism.