Birth outcomes in women with gestational diabetes managed by lifestyle modification alone: The PANDORA study

AIMS

To assess outcomes of women in the Pregnancy and Neonatal Diabetes Outcomes in Remote Australia (PANDORA) cohort with gestational diabetes mellitus (GDM) managed by lifestyle modification compared with women without hyperglycaemia in pregnancy.

METHODS

Indigenous (n = 97) and Europid (n = 113) women managed by lifestyle modification were compared to women without hyperglycaemia (n = 235). Multivariate linear and logistic regressions assessed whether GDM-lifestyle women had poorer outcomes compared to women without hyperglycaemia.

RESULTS

Women with GDM-lifestyle had higher body mass index and lower gestational weight gain than women without hyperglycaemia. On univariate analysis, gestational age at delivery was lower and induction rates were higher in women with GDM-lifestyle than without hyperglycaemia. On multivariable regression, GDM-lifestyle was associated with lower gestational age at delivery (by 0.73 weeks), lower birthweight z-score (by 0.26, p = 0.007), lower likelihood of large for gestational age (LGA) [OR (95% CI): 0.55 (0.28, 1.02), p = 0.059], and greater likelihood of labour induction [2.34 (1.49, 3.66), p < 0.001] than women without hyperglycaemia.

CONCLUSION

Women with GDM managed by lifestyle modification had higher induction rates and their offspring had lower birthweight z-scores, with a trend to lower LGA than those without hyperglycaemia in pregnancy. Further studies are indicated to explore reasons for higher induction rates.

Diabetes care in remote Australia: the antenatal, postpartum and inter-pregnancy period

BACKGROUND

Aboriginal and Torres Strait Islander women experience high rates of diabetes in pregnancy (DIP), contributing to health risks for mother and infant, and the intergenerational cycle of diabetes. By enhancing diabetes management during pregnancy, postpartum and the interval between pregnancies, the DIP Partnership aims to improve health outcomes and reduce risks early in the life-course. We describe a mixed methods formative study of health professional's perspectives of antenatal and post-partum diabetes screening and management, including enablers and barriers to care.

METHODS

Health professionals involved in providing diabetes care in pregnancy, from a range of health services across the Northern Territory, completed the survey (n = 82) and/or took part in interviews and/or focus groups (n = 62).

RESULTS

Qualitative findings highlighted factors influencing the delivery of care as reported by health professionals, including: whose responsibility it is, access to care, the baby is the focus and pre-conception care. The main challenges were related to: disjointed systems and confusion around whose role it is to provide follow-up care beyond six weeks post-partum. Quantitative findings indicated that the majority of health professionals reported confidence in their own skills to manage women in the antenatal period (62%, 40/79) and slightly lower rates of confidence in the postpartum interval (57%, 33/58).

CONCLUSION

These findings regarding whose role it is to provide postpartum care, along with opportunities to improve communication pathways and follow up care have informed the design of a complex health intervention to improve health systems and the provision of DIP related care.

Parental pre-pregnancy obesity and the risk of offspring weight and body mass index change from childhood to adulthood

The purpose of this study was to examine the association of parental pre-pregnancy weight and body mass index (BMI) on offspring weight and BMI change from childhood to adulthood. We analysed BMI data from a subsample of parents (n = 1494) from the Mater-University of Queensland Study of Pregnancy cohort that started in the early 1980s in Brisbane, Australia: data were collected at pre-pregnancy and then also for offspring at 5, 14 and 21-year follow-ups. Multiple regression for continuous outcomes and multinomial regression for categorical outcomes were performed. A total of 14.7% of offspring experienced BMI change from normal at 5 years to overweight or obese (OW/OB) at 14 years, 15.3% of normal at 14 years to OW/OB at 21 years and 22.8% from normal at 5 years to OW/OB at 21 years. Overall, the strength of the association of parental BMI with offspring BMI was stronger as offspring become older. Pre-pregnancy parental BMI differentially impacts offspring OW/OB across the life course. For every unit increase in paternal and maternal BMI z-score, offspring BMI z-score increased, on average, by between 0.15% (kg m^-2 ) and 0.24% (kg m^-2 ) throughout all three stages of life when both parents were OW/OB; these associations were stronger than with one parent. Parental pre-pregnancy BMI and OW/OB is a strong predictor of offspring weight and BMI change from early life to adulthood.

Glycaemic behaviour during breastfeeding in women with Type 1 diabetes

AIM

To describe glycaemia in both breastfeeding women and artificially feeding women with Type 1 diabetes, and the changes in glycaemia induced by suckling.

METHODS

A blinded continuous glucose monitor was applied for up to 6 days in eight breastfeeding and eight artificially feeding women with Type 1 diabetes 2-4 months postpartum. Women recorded glucose levels, insulin dosages, oral intake and breastfeeding episodes. A standardized breakfast was consumed on 2 days. A third group (clinic controls) were identified from a historical database.

RESULTS

Carbohydrate intake tended to be higher in breastfeeding than artificially feeding women (P = 0.09) despite similar insulin requirements. Compared with breastfeeding women, the high blood glucose index and standard deviation of glucose were higher in artificially feeding women (P = 0.02 and 0.06, respectively) and in the clinical control group (P = 0.02 and 0.05, respectively). The low blood glucose index and hypoglycaemia were similar. After suckling, the low blood glucose index increased compared with before (P < 0.01) and during (P < 0.01) suckling. Hypoglycaemia (blood glucose < 4.0 mmol/l) occurred within 3 h of suckling in 14% of suckling episodes, and was associated with time from last oral intake (P = 0.04) and last rapid-acting insulin (P = 0.03). After a standardized breakfast, the area under the glucose curve was positive. In breastfeeding women the area under the glucose curve was positive if suckling was avoided for 1 h after eating and negative if suckling occurred within 30 min of eating.

CONCLUSIONS

Breastfeeding women with Type 1 diabetes had similar hypoglycaemia but lower glucose variability than artificially feeding women. Suckling reduced maternal glucose levels but did not cause hypoglycaemia in most episodes.

A Randomised Controlled Trial to Delay or Prevent Type 2 Diabetes after Gestational Diabetes: Walking for Exercise and Nutrition to Prevent Diabetes for You

Aims. To develop a program to support behaviour changes for women with a history of Gestational Diabetes Mellitus (GDM) and a Body Mass Index (BMI) > 25 kg/m(2) to delay or prevent Type 2 Diabetes Mellitus. Methods. Women diagnosed with GDM in the previous 6 to 24 months and BMI > 25 kg/m(2) were randomized to an intervention (I) (n = 16) or a control (C) (n = 15) group. The intervention was a pedometer program combined with nutrition coaching, with the primary outcome increased weight loss in the intervention group. Secondary outcomes included decreased waist and hip measurements, improved insulin sensitivity and body composition, increased physical activity, and improved self-efficacy in eating behaviours. Results. Median (IQR) results were as follows: weight: I -2.5 (2.3) kg versus C +0.2 (1.6) kg (P = 0.009), waist: I -3.6 (4.5) cm versus C -0.1 (3.6) cm (P = 0.07), and hip: I -5.0 (3.3) cm versus C -0.2 (2.6) cm (P = 0.002). There was clinical improvement in physical activity and eating behaviours and no significant changes in glucose metabolism or body composition. Conclusion. A pedometer program and nutrition coaching proved effective in supporting weight loss, waist circumference, physical activity, and eating behaviours in women with previous GDM.

Trial for Reducing Weight Retention in New Mums: a randomised controlled trial evaluating a low intensity, postpartum weight management programme

BACKGROUND

Failure to return to pregnancy weight by 6 months postpartum is associated with long-term obesity, as well as adverse health outcomes. This research evaluated a postpartum weight management programme for women with a body mass index (BMI) > 25 kg m(-2) that combined behaviour change principles and a low-intensity delivery format with postpartum nutrition information.

METHODS

Women were randomised at 24-28 weeks to control (supported care; SC) or intervention (enhanced care; EC) groups, stratified by BMI cohort. At 36 weeks of gestation, SC women received a 'nutrition for breastfeeding' resource and EC women received a nutrition assessment and goal-setting session about post-natal nutrition, plus a 6-month correspondence intervention requiring return of self-monitoring sheets. Weight change, anthropometry, diet, physical activity, breastfeeding, fasting glucose and insulin measures were assessed at 6 weeks and 6 months postpartum.

RESULTS

Seventy-seven percent (40 EC and 41 SC) of the 105 women approached were recruited; 36 EC and 35 SC women received a programme and 66.7% and 48.6% completed the study, respectively. No significant differences were observed between any outcomes. Median [interquartile range (IQR)] weight change was EC: -1.1 (9.5) kg versus SC: -1.1 (7.5) kg (6 weeks to 6 months) and EC: +1.0 (8.7) kg versus SC: +2.3 (9) kg (prepregnancy to 6 months). Intervention women breastfed for half a month longer than control women (180 versus 164 days; P = 0.10). An average of 2.3 out of six activity sheets per participant was returned.

CONCLUSIONS

Despite low intervention engagement, the high retention rate suggests this remains an area of interest to women. Future strategies must facilitate women's engagement, be individually tailored, and include features that support behaviour change to decrease women's risk of chronic health issues.

Human placental sulfate transporter mRNA profiling from term pregnancies identifies abundant SLC13A4 in syncytiotrophoblasts and SLC26A2 in cytotrophoblasts

Sulfate is an important nutrient for fetal growth and development. The fetus has no mechanism for producing its own sulfate and is therefore totally reliant on sulfate from the maternal circulation via placental sulfate transport. To build a model of directional sulfate transport in the placenta, we investigated the relative abundance of the 10 known sulfate transporter mRNAs in human placenta from uncomplicated term pregnancies. SLC13A4 and SLC26A2 were the most abundant sulfate transporter mRNAs, which localized to syncytiotrophoblast and cytotrophoblast cells, respectively. These findings indicate important physiological roles for SLC13A4 and SLC26A2 in human placental sulfate transport.

Insulin requirements in late pregnancy in women with type 1 diabetes mellitus: a retrospective review

Pregnancy in women with type 1 diabetes mellitus (T1DM) is generally associated with increased insulin requirements.

AIMS

To determine the frequency and significance of declining insulin requirements in late gestation in women with T1DM.

METHODS

We conducted a retrospective review of 54 women seen at our institution from 2006 to 2010 with a diagnosis of T1DM pre-pregnancy and presentation for antenatal care prior to 28 weeks. Information was collected regarding patient demographics, insulin dose and pregnancy outcome. A 15% difference in weight-adjusted basal insulin from 30 weeks gestation to delivery was considered significant.

RESULTS

Five women (9.3%) had a fall of 15% or more and 23 (42.5%) had a rise of 15% or more rise in insulin requirements. There were fewer neonatal intensive care admissions but more infants with an APGAR <8 at 5 min in women with a fall in insulin requirements. These differences were not evident when the data were re-analysed by quartiles of change.

CONCLUSIONS

In most women with T1DM, insulin requirements show little change from 30 weeks gestation until delivery. Almost 10% of women had a significant fall in insulin requirements which did not correlate with adverse neonatal outcome. These results require validation in a larger, prospective trial.

Associations of serum vitamin D concentrations with obstetric glucose metabolism in a subset of the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) study cohort

AIMS

To assess associations between maternal serum vitamin D concentration and glucose metabolism in a cohort of pregnant women living in an Australian subtropical environment.

METHODS

Cross-sectional assessment of 25-hydroxy vitamin D concentrations in 399 Hyperglycemia and Adverse Pregnancy Outcome ancillary study participants, treated at an obstetric teaching hospital in Brisbane, Australia. All patients underwent a blinded 75-g oral glucose tolerance test at 24-32 (target 28) weeks' gestation.

RESULTS

The mean (± standard deviation) fasting plasma glucose was 4.5 ± 0.4 mmol/l. Mean (± standard deviation) serum 25-hydroxy vitamin D was 132.5 ± 44.0 nmol/l. A difference of one standard deviation in maternal 25-hydroxy vitamin D was inversely related to fasting glucose (fasting glucose lower by 0.047 mmol/l, P=0.012) when assessed with multiple linear regression after adjusting for confounders. Maternal 25-hydroxy vitamin D correlated with β-cell function as estimated by the log-transformed homeostasis model assessment-β-cell function equation (r=0.131, P=0.009), but not with the homeostasis model assessment of insulin resistance.

CONCLUSIONS

An association between mid-gestational 25-hydroxy vitamin D and fasting glucose was confirmed in a largely normoglycaemic and vitamin D-replete pregnant population. The correlation between 25-hydroxy vitamin D and β-cell function suggests that vitamin D may influence glucose metabolism through this mechanism. Intervention studies are required to determine causality and the role of vitamin D replacement in deficient individuals.

Subclinical hypothyroidism and related biochemical entities in pregnancy: implications and management

Subclinical hypothyroidism (SCH), thyroid autoimmunity and isolated maternal hypothyroxinaemia are diagnoses made on laboratory findings. The two former conditions are commonly identified in the general population, while the term isolated maternal hypothyroxinaemia was developed to highlight potential neurodevelopmental risks in progeny. Each entity has been associated with either obstetric, perinatal and/or child developmental harm in observational studies, although few interventional trials have been performed to guide diagnostic and therapeutic approaches. Once diagnosed, treatment of SCH is recommended by endocrine groups to limit potential risk, given that harm from appropriate therapy is unlikely. Screening for thyroid disorders in pregnancy has traditionally been controversial. Definitive trials are expected to report over coming years and updated consensus guidelines will hopefully resolve this issue.

Ductus venosus velocimetry in monitoring pregnancy in women with pregestational diabetes mellitus

OBJECTIVE

The purpose of this research was to assess the ability of ductus venosus (DV) Doppler velocimetry to predict adverse perinatal outcome in pregnancies complicated by pre-existing diabetes mellitus.

METHODS

This was a prospective study conducted at a tertiary referral obstetric facility in Brisbane, Australia. The study group included women with pregestational diabetes mellitus who delivered in the hospital between 1 January 1995 and 31 December 2006. The DV Doppler index was defined as abnormal if the DV peak velocity index for veins (PVIV) was equal to or greater than the 95(th) percentile for gestation. Adverse perinatal outcome included one or more of the following criteria: small-for-gestational-age infant; Cesarean section for non-reassuring fetal status; fetal acidemia at delivery; a 1-min Apgar score of <or= 3; a 5-min Apgar score of < 7; hypoxic ischemic encephalopathy; and stillbirth or neonatal death. The maternal characteristics and perinatal outcomes of pregnancies with normal or abnormal DV Doppler indices were compared.

RESULTS

Eighty-two pregestational diabetic pregnancies were studied and an abnormal DV-PVIV was identified in 25 (30.5%). Adverse perinatal outcome was identified in eight of 25 (32.0%) pregnancies with an abnormal DV-PVIV compared to seven of 57 (12.3%) pregnancies with a normal DV-PVIV (P < 0.05). The sensitivity of the DV-PVIV in predicting adverse perinatal outcomes in pregestational diabetic pregnancies was 53.3%, the specificity was 74.6%, the positive predictive value was 32.0% and the negative predictive value was 87.7%.

CONCLUSION

It may be useful to include DV-PVIV in the antenatal screening of pregnancies complicated by pregestational diabetes.

Placental growth hormone, fetal growth and the IGF axis in normal and diabetic pregnancy

Gestational diabetes mellitus (GDM) and pre-gestational diabetes are known to pose risks to the mother and developing fetus, often related to abnormal fetal growth. One potential mediator of maternal effects on fetal growth is Placental Growth Hormone (PGH). PGH is produced by the syncytiotrophoblast and found predominantly in the maternal circulation. It progressively replaces pituitary growth hormone (hGH) in the human maternal circulation from mid-gestation onwards, peaking towards term. PGH appears to be an important potential regulator of maternal insulin resistance in human pregnancy and may influence fetal growth both by modifying substrate availability and through paracrine actions in the placental bed. The details of PGH regulation remain relatively poorly understood, but current evidence does suggest a central role in growth restricted pregnancies. There is currently less evidence of a pathophysiologic role in production of the macrosomic fetal phenotype commonly seen in response to hyperglycaemia, although our recent in vitro studies do raise the possibility of feto-placental feedback as a mechanism of growth modulation.

Pregnancy in type 2 diabetes mellitus--problems & promises

The parallel epidemics of obesity and Type 2 diabetes (T2DM) are progressing rapidly in Australia. The high prevalence of obesity and sedentary lifestyle in the population, compounded by later child bearing, has led to an increase in the prevalence of T2DM pre-dating pregnancy. In some centers, pregnant women with T2DM now outnumber those with type 1 diabetes (T1DM). Although there is controversy as to whether T2DM is associated with worse outcomes than T1DM in pregnancy, modern reports clearly acknowledge the seriousness of this condition. There is a clear association between obesity and adverse pregnancy outcomes (cesarean section, gestational diabetes, hypertensive disorders, birth defects and prematurity). Aside from obesity and the metabolic syndrome, additional factors may contribute to these adverse outcomes: A lack of preconception planning, a failure to achieve tight glycaemic control early in pregnancy and socio-economic disadvantage. It's likely that obesity and diabetes have compounding effects on pregnancy outcomes. In this review, we evaluate both the underlying pathogenesis of T2DM and obesity in the pregnancy context and the adverse clinical maternal and perinatal outcomes described in pregnancies complicated by maternal T2DM and obesity. We highlight the need for a comprehensive strategy to improve clinical outcomes in these pregnancies.

[Gestational diabetes in East Africa: a mostly disregarded disease?]

The majority of all deliveries worldwide take place in the so-called developing world. Most recent epidemiological data have shown that the number of cases of type 2 diabetes mellitus and diabetes in pregnancy is steadily increasing worldwide. However, little is known about the prevalence of gestational diabetes in East Africa. Intrauterine exposure to the metabolic environment of maternal diabetes increases the risk of altered glucose homeostasis in the offspring, producing a higher prevalence of gestational diabetes mellitus in the next generation. Our preliminary results from an East African tertiary referral center show that in the year 2007 3.1% of all newborns had a birth weight of more than 4,000 g (mean 4,300 g, range 4,000- 5,600 g). During the same time period, the mean birth weight in the general population was only 3,046 g (range 600-3,200 g). Hence, personal experience in East Africa has convinced the authors that diabetes in pregnancy is grossly neglected. Besides infectious diseases like HIV/AIDS, the African continent is increasingly facing metabolic diseases such as type 2 diabetes mellitus and diabetes in pregnancy.

[The dilemma of diabetes in pregnancy: worldwide differences in diagnosis and management]

OBJECTIVE

Type 1 and type 2 diabetes in pregnancy as well as gestational diabetes mellitus (GDM) pose major risks to mother and fetus. We assessed to which extent two obstetric centers on two different continents coincide in their management of diabetes in pregnancy.

METHODS

Within the scope of research activities between the Obstetric Department of the Medical University of Graz, Austria, and the Centre of Obstetric Medicine at the Mater Misericordiae Mothers' Hospital in Brisbane, Australia, current practices among the two obstetric centers in Austria and Australia were assessed.

RESULTS

The management of type 1 and type 2 diabetes in pregnancy was almost identical, whereas major differences were found in the management of GDM.

CONCLUSION

Standardization of screening methods in diabetes in pregnancy remains challenging. National and international consensus has yet to be achieved in order to put a hold to the 'diabetic epidemic' we are going to face in the future.

Fetal growth patterns in fetuses of women with pregestational diabetes mellitus

OBJECTIVE

To assess the effect of glucose control on the rate of growth of fetuses in women with pregestational diabetes mellitus (Types 1 and 2).

METHODS

All pregestational diabetic women booked at Mater Mothers' Hospital, Brisbane, Australia, between 1 January 1994 and 31 December 2002, were included. Pregnancies with congenital fetal anomalies, multiple pregnancies, and pregnancies terminated prior to 20 weeks' gestation were excluded. Dating scans were performed before 14 weeks' gestation and serial scans were performed at 18, 24, 28, 32 and 36 weeks. Fetal parameters, including biparietal diameter, femur length and abdominal circumference, were recorded. The daily growth rates for biparietal diameter, femur length, and fetal abdominal area were calculated and compared with those in a low-risk (non-diabetic) population. The growth rates in fetuses of women with satisfactory diabetic control (HbA1c < 6.5%) and unsatisfactory control (HbA1c > or = 6.5%) in the three trimesters were compared.

RESULTS

A total of 174 diabetic pregnancies were included and a total of 997 ultrasound scans were performed. The growth rates for fetuses of mothers with diabetes mellitus were significantly higher than for those in the low-risk population. The z-scores for biparietal diameter, femur length, and fetal abdominal area were 0.18, 0.59 and 1.44, respectively. Fetuses of diabetic mothers with high HbA1c in the first trimester had significantly greater fetal abdominal area growth rate than those with normal HbA1c (fetal abdominal area z-score of 1.7 vs. 0.75, P = 0.009). Although the fetal abdominal area z-scores in fetuses of diabetic mothers with high HbA1c in the second or third trimesters were also higher than those with normal HbA1c levels, the differences did not reach statistical significance. Maternal obesity did not influence the fetal growth rate.

CONCLUSION

The rate of growth of fetuses of diabetic mothers differs from that of the normal population. Growth acceleration persists until the late third trimester. Moreover, periconceptional glucose control appears to have a significant effect on accelerated growth of the fetal abdominal area.

Cardiac function in fetuses of poorly-controlled pre-gestational diabetic pregnancies--a pilot study

OBJECTIVE

Cardiac impairment is frequently found in babies of diabetic mothers. It is still controversial whether this is due to poor glucose control. The aim of this study is to compare the cardiac function in fetuses of well- and poorly-controlled pre-gestational diabetic pregnancy in third trimester.

METHODS

Women with type 1 pre-gestational diabetes were enrolled at 30-32 weeks. Cardiac size and interventricular septal wall thickness were measured by M-mode at end-diastolic phase. The right and left ventricular ejection fractions were calculated. At the mitral and tricuspid valves inflow, the ratio between early ventricular filling and active atrial filling (E/A) at both atrioventricular valves were measured by Doppler echocardiography. Peak velocities of ascending aorta and pulmonary artery were assessed. The angle of isonation was kept at <20 degrees. Women with poorly-controlled diabetes (HbA1c>6.5%) were compared with those with satisfactorily controlled diabetes (HbA1c < or = 6.5%).

RESULTS

A total of 21 women with pre-gestational diabetes were recruited for this study. Eight women with well-controlled diabetes were compared with 9 women who had poorly-controlled diabetes. HbA1c in the poorly-controlled group was 7.3% and in the well-controlled group it was 5.4% (p<0.001). There was no difference between the two groups in cardiac size, interventricular septal wall thickness, ejection fraction, aorta and pulmonary artery peak flow velocities. The right atrioventricular E/A ratio was significantly lower among the poorly-controlled diabetic pregnancies (0.71 vs. 0.54; p<0.05).

CONCLUSION

Fetuses of poorly-controlled diabetic mothers had a lower right atrioventricular E/A ratio. This may be due to metabolic acidosis, non-hypertrophic cardiac dysfunction or fetal polycythemia.

Placental growth hormone is not suppressed by oral glucose loading in normal human pregnancy

Placental growth hormone (PGH) progressively replaces pituitary growth hormone in the maternal circulation from mid-gestation onwards in human pregnancy. Our previous investigations have shown that placental growth hormone concentrations correlate well with foetal growth. Despite the apparent correlation between PGH and birthweight, the physiology of its secretion during pregnancy has not been well defined. We investigated the response of maternal serum PGH to oral glucose loading in pregnant women (n = 24) who demonstrated normal glucose tolerance at a mean gestation of 29 weeks. Mean (SEM) fasting PGH concentrations were high (36.9 [6.4] ng/ml). No suppression of PGH was noted at one, two or three hours after a 75 g oral glucose load. Similarly, no changes were noted in growth hormone binding protein or in calculated free PGH over the course of the glucose tolerance test. As expected, insulin concentrations rose sixfold and insulin like growth factor binding protein 1 concentrations fell by 20 % with glucose loading. Correlation analysis showed maternal weight, BMI, fasting serum glucose serum insulin to be significantly correlated with the babies' birthweight. Our results support the proposition that PGH concentrations in maternal serum are not suppressed by oral glucose loading in non-diabetic mothers.

Routine ultrasound screening in diabetic pregnancies

OBJECTIVES

To assess the detection rate of congenital fetal malformations and specific problems related to routine ultrasound screening in women with pre-existing diabetes.

METHODS

A retrospective study was carried out to assess the performance of routine ultrasound screening in women with pre-existing diabetes (Types 1 and 2) within a tertiary institution. The incidence, type and risk factors for congenital fetal malformations were determined. The detection rate of fetal anomalies for diabetic women was compared with that for the low-risk population. Factors affecting these detection rates were evaluated.

RESULTS

During the study period, 12 169 low-risk pregnant women and 130 women with pre-existing diabetes had routine ultrasound screening performed within the institution. A total of 10 major anomalies (7.7%) and three minor anomalies (2.3%) were present in the fetuses of the diabetic women. Central nervous system and cardiovascular system anomalies accounted for 60% of the major anomalies. Periconceptional hemoglobin A1c of more than 9% was associated with a high prevalence of major anomalies (143/1000). Women who had fetuses with major anomalies had a significantly higher incidence of obesity (78% vs. 37%; P < 0.05). Ultrasound examination of these diabetic pregnancies showed high incidences of suboptimal image quality (37%), incomplete examinations, and repeat examinations (17%). Compared to the 'low-risk' non-diabetic population from the same institution, the relative risk for a major congenital anomaly among the diabetic women was 5.9-fold higher (95% confidence interval, 2.9-11.9). The detection rate for major fetal anomalies was significantly lower for diabetic women (30% vs. 73%; P < 0.01), and the mean body mass index for the diabetic group was significantly higher (29 vs. 23 kg/m2; P < 0.001).

CONCLUSION

The incidence of congenital anomalies is higher in diabetic pregnancies. Unfortunately, the detection rate for fetal anomalies by antenatal ultrasound scan was significantly worse than that for the low-risk population. This is likely to be related to the maternal body habitus and unsatisfactory examinations. Methods to overcome these difficulties are discussed.

Sonographic estimation of fetal weight in macrosomic fetuses: diabetic versus non-diabetic pregnancies

The objective of this study is to compare the accuracy of sonographic estimation of fetal weight of macrosomic babies in diabetic vs non-diabetic pregnancies. All babies weighing 4,000 g or more at birth, and who had ultrasound scans performed within one week of delivery were included in this retrospective study Pregnancies with diabetes mellitus were compared to those without diabetes mellitus. The mean simple error (actual birthweight--estimated fetal weight); mean standardised absolute error (absolute value of simple error (g)/actual birthweight (kg)); and the percentage of estimated birthweight falling within 15% of the actual birthweight between the two groups were compared. There were 9,516 deliveries during the study period. Of this total 1,211 (12.7%) babies weighed 4,000 g or more. A total of 56 non-diabetic pregnancies and 19 diabetic pregnancies were compared. The average sonographic estimation of fetal weight in diabetic pregnancies was 8% less than the actual birthweight, compared to 0.2% in the non-diabetic group (p < 0.01). The estimated fetal weight was within 15% of the birthweight in 74% of the diabetic pregnancies, compared to 93% of the non-diabetic pregnancies (p < 0.05). In the diabetic group, 26.3 % of the birthweights were underestimated by more than 15 %, compared to 5.4% in the non-diabetic group (p < 0.05). In conclusion, the prediction accuracy of fetal weight estimation using standard formulae in macrosomic fetuses is significantly worse in diabetic pregnancies compared to non-diabetic pregnancies. When sonographic fetal weight estimation is used to influence the mode of delivery for diabetic women, a more conservative cut-off needs to be considered.

Congenital thyrotoxicosis in premature infants

OBJECTIVES

Graves' disease (GD) complicates 0.1% to 0.2% of pregnancies, but congenital thyrotoxicosis is rare occurring in one in 70 of these pregnancies independent of maternal disease status. Antenatal prediction of affected infants is imprecise; however, maternal history, coupled with a high maternal serum TSH receptor binding immunoglobulin index (TBII) predict adverse neonatal outcome. Mortality is reported to be as high as 25% in affected infants and would therefore be expected to be higher in premature infants. This study illustrates that in sick, premature, extreme low birth weight (ELBW) or intrauterine growth retarded (IUGR) infants, the diagnosis maybe overlooked especially in the absence of antenatal risk assessment and management of thyrotoxicosis in this setting is complex.

DESIGN AND PATIENTS

The records of premature neonates born at the three main maternity units in Brisbane, between January 1996 and July 1998 diagnosed with congenital thyrotoxicosis were reviewed. Data were recorded on gestational age, birth weight (B Wt), maternal thyroid history and current status, and neonatal course. Thyroid function and TBII status was assessed using standard biochemical assays.

RESULTS

Seven neonates from five pregnancies were identified (four female, three male). Mean gestational age was 30 week (25--36 week) and median B Wt was 1.96 kg (0.50--2.62 kg). Only one mother received formal antenatal counselling by a paediatric endocrine service and had a TBII (54%) measured prior to delivery. Three of five mothers had elevated TBII measured after diagnosis in their offspring (57%, 65%, 83%) and in one mother, a TBII was not performed. All mothers were biochemically euthyroid at delivery. Mean age at diagnosis was 9 days (1--16 days) and mean age at commencement of treatment was 12 days (7--26 days). Two infants received propylthiouracil and five received a combination of carbimazole and propranolol. Four became biochemically hypothyroid, in three this resolved with cessation of the antithyroid drug (ATD), and one required ongoing T4 supple-mentation. Only one infant required treatment for cardiac failure and there were no deaths in this cohort.

CONCLUSIONS

This is a large series of extremely small and premature infants with neonatal thyro-toxicosis. Presentation was nonspecific. The diagnosis was delayed because of low birth weight, prematurity, multiple birth and/or an unrecognized maternal history of Graves' disease. The treatment of neonatal thyrotoxicosis was difficult in these extreme low birth weight infants yet no infant died and significant morbidity was confined to high output cardiac failure in one infant. With antenatal recognition of past or active Graves' disease, assessment of maternal TSH receptor binding immunoglobulin index prior to delivery and postnatal monitoring of cord TSH and venous fT4 and TSH on days 4 and 7 rapid treatment of affected infants may have further reduced neonatal morbidity.

Placental growth hormone (GH), GH-binding protein, and insulin-like growth factor axis in normal, growth-retarded, and diabetic pregnancies: correlations with fetal growth

We previously described significant changes in GH-binding protein (GHBP) in pathological human pregnancy. There was a substantial elevation of GHBP in cases ofnoninsulin-dependent diabetes mellitus and a reduction in insulin-dependent diabetes mellitus. GHBP has the potential to modulate the proportion of free placental GH (PGH) and hence the impact on the maternal GH/insulin-like growth factor I (IGF-I) axis, fetal growth, and maternal glycemic status. The present study was undertaken to investigate the relationship among glycemia, GHBP, and PGH during pregnancy and to assess the impact of GHBP on the concentration of free PGH. We have extended the analysis of specimens to include measurements of GHBP, PGH, IGF-I, IGF-II, IGF-binding protein-1 (IGFBP-1), IGFBP-2, and IGFBP-3 and have related these to maternal characteristics, fetal growth, and glycemia. The simultaneous measurement of GHBP and PGH has for the first time allowed calculation of the free component of PGH and correlation of the free component to indexes of fetal growth and other endocrine markers. PGH, free PGH, IGF-I, and IGF-II were substantially decreased in IUGR at 28-30 weeks gestation (K28) and 36-38 weeks gestation (K36). The mean concentration (+/-SEM) of total PGH increased significantly from K28 to K36 (30.0 +/- 2.2 to 50.7 +/- 6.2 ng/mL; n = 40), as did the concentration of free PGH (23.4 +/- 2.3 to 43.7 +/- 6.0 ng/mL; n = 38). The mean percentage of free PGH was significantly less in IUGR than in normal subjects (67% vs. 79%; P < 0.01). Macrosomia was associated with an increase in these parameters that did not reach statistical significance. Multiple regression analysis revealed that PGH/IGF-I and IGFBP-3 account for 40% of the variance in birth weight. IGFBP-3 showed a significant correlation with IGF-I, IGF-II, and free and total PGH at K28 and K36. Noninsulin-dependent diabetes mellitus patients had a lower mean percentage of free PGH (65%; P < 0.01), and insulin-dependent diabetics had a higher mean percentage of free PGH (87%; P < 0.01) than normal subjects. Mean postprandial glucose at K28 correlated positively with PGH and free PGH (consistent with the hyperglycemic action of GH). GHBP correlated negatively with both postprandial and fasting glucose. Although GHBP correlated negatively with PGH (r = -0.52; P < .001), free PGH and total PGH correlated very closely (r = 0.98). The results are consistent with an inhibitory function for GHBP in vivo and support a critical role for placental GH and IGF-I in driving normal fetal growth.

Growth hormone-binding protein in normal and pathologic gestation: correlations with maternal diabetes and fetal growth

To date, measurements of GH-binding protein (GHBP) during human pregnancy have been carried out using assays susceptible to interference by the elevated levels of human placental GH typical of late gestation. We recruited a large cohort of pregnant women (n = 140) for serial measurements of GHBP and used the ligand immunofunctional assay for GHBP. For normal gravidas, GHBP levels fell throughout gestation. Mean levels were 1.07 nmol/L (SE = 0.18) in the first trimester, 0.90 nmol/L (SE = 0.08) at 18-20 weeks, 0.73 nmol/L (SE = 0.05) at 28-30 weeks, and 0.62 nmol/L (SE = 0.06) at 36-38 weeks. GHBP levels in the first trimester correlated significantly with maternal body mass index (r = 0.58; P < 0.01). GHBP levels in pregnancies complicated by noninsulin-dependent diabetes mellitus (NIDDM) were substantially elevated at all gestational ages. The mean value in the first quarter (2.29 nmol/L) was more than double the normal mean (P < 0.01). In contrast, patients with insulin-dependent diabetes mellitus (IDDM) showed reduced GHBP concentrations at 36-38 weeks. The correlation between body mass index and GHBP is consistent with a metabolic role for GHBP during pregnancy, as is the dramatic elevation in GHBP observed in cases of NIDDM. At 36 weeks gestation, GHBP was significantly elevated (P < 0.01) in those women whose neonates had low birth weight (< 10th percentile). In early gestation (< 14 weeks), GHBP tended to be higher in women whose fetuses were designated to be at risk of intrauterine growth retardation (1.39 nmol/L; n = 4; compared with 1.07 nmol/L in normals), but this did not reach statistical significance. Although both NIDDM and IDDM pregnancies are at risk of fetal macrosomia, their GHBP concentrations are markedly divergent. This paradox and the roles of glucose and insulin in the regulation of GHBP during gestation warrant further investigation.

The role of DEXA bone densitometry in evaluating renal osteodystrophy in continuous ambulatory peritoneal dialysis patients

OBJECTIVE

The aims of this study were to assess the clinical utility of total and regional bone densitometry in a large continuous ambulatory peritoneal dialysis (CAPD) population and to determine the clinical, biochemical, and radiographic variables that best identified osteopenic CAPD patients.

DESIGN AND PATIENTS

A cross-sectional study was performed on 45 CAPD patients (19 males, 26 females), comprising the total CAPD population at the Princess Alexandra Hospital.

MAIN OUTCOME MEASURES

Total body (TB), anteroposterior lumbar spine (APL), femoral neck (FN), Ward's triangle (WT), and skull bone mineral densities (BMDs) were measured using dual-energy x-ray absorptiometry (DEXA) and then correlated with clinical, biochemical, and radiographic indices of uremic osteodystrophy.

RESULTS

BMDs were not significantly different from age- and sex-matched reference population data. Considerable regional variation of BMD Z scores were noted between FN (-0.11 +/- 0.23), WT (-0.11 +/- 0.22), and APL (1.22 +/- 0.04) (p = 0.003). APLZ scores were significantly reduced in patients with a previous history of fracture (-1.36 +/- 1.07 vs 0.89 +/- 0.31), bone pain (-0.72 +/- 1.08 vs 1.01 +/- 0.31), or steroid treatment (-0.62 +/- 0.39 vs 1.16 +/- 0.35). Increased BMD Z scores for APL (1.82 +/- 0.57 vs 0.38 +/- 0.29, p < 0.05), FN (0.32 +/- 0.36 vs -0.38 +/- 0.29, p = 0.014), and WT (0.45 +/- 0.38 vs -0.45 +/- 0.26, p < 0.05) were found in patients with radiographic hyperparathyroid bone disease. Both APL BMD Z scores and skull BMDs were weakly correlated with PTH (r = -0.33, p < 0.05 and r = -0.33, p < 0.05, respectively) and with CAPD duration (r = 0.30, p < 0.05 and r = -0.30, p < 0.05). Generally, however, total body and regional BMDs were poorly related to age, renal disease type, dialysis duration, renal failure duration, serum aluminum, calcium, phosphate, alkaline phosphatase, osteocalcin, and parathyroid hormone.

CONCLUSIONS

We conclude that the prevalence of osteopenia is not increased in CAPD patients. Clinical and biochemical parameters do not reliably predict BMD measurements, but prior steroids and bone symptoms are major risk factors for important bone loss. Although DEXA can reliably detect osteopenia in different skeletal regions, its usefulness in detecting osteodystrophy is limited by the confounding effects of superimposed hyperparathyroid osteosclerosis, which increases BMD.

A randomized trial comparing 1.25 mmol/l calcium dialysate to 1.75 mmol/l calcium dialysate in CAPD patients

BACKGROUND

Effective control of hyperparathyroidism and renal osteodystrophy in CAPD patients requires a combination of calcitriol and calcium carbonate (CaCO3), but is frequently limited by hypercalcaemia. Reducing dialysate calcium (Ca) concentration may overcome this problem, but had not been examined in a controlled trial.

METHODS

45 stable CAPD patients were randomly assigned in a prospective double-blind trial to either a study group (1.25 mmol/l Ca dialysate) or a control group (1.75 mmol/l Ca dialysate) for 12 months. Clinical, biochemical and radiological parameters of secondary hyperparathyroidism were followed.

RESULTS

Twenty-three patients did not complete the study due to death (9), transplantation (7) or conversion to haemodialysis (7). Eleven patients in each group completed the study. Mean serum Ca, phosphate, ionized Ca, aluminium, alkaline phosphatase (AP), and bone mineral density (BMD) Z-scores did not differ significantly at any time within or between the two groups. Severe hypercalcaemia was more common in the control group (11 vs. 2, P = 0.027). Mean serum intact parathyroid hormone (PTH) and osteocalcin (OCN) initially rose in the study group relative to controls at 3 months (40 +/- 7 vs 12 +/- 3 pmol/l, P = 0.004, and 33 +/- 5 vs 15 +/- 2 micrograms/l, P = 0.002 respectively), but were not sustained. Median weekly dosages of calcitriol and daily dosages of CaCO3 increased significantly in the study group (O microgram to 1 microgram P = 0.014 and 1260 mg to 2520 mg P = 0.002 respectively), but not in the control group. Supplementary aluminium hydroxide (A1, (OH)3) was required for phosphate control in both study (n = 5) and control patients (n = 4).

CONCLUSIONS

Lowering dialysate calcium concentration reduced the frequency of severe hypercalcaemia and allowed prescription of larger quantities of calcitriol and CaCO3. However, in this study it offered no advantage in terms of A1(OH)3 requirement, while bone mass density did and may have initially exacerbated secondary hyperparathyroidism not change.

Measuring the systemic effects of inhaled beclomethasone: timed morning urine collections compared with 24 hour specimens

BACKGROUND

Inhaled glucocorticoid therapy has systemic effects including hypothalamic-pituitary-adrenal (HPA) suppression. The optimal test for detecting these effects has not been defined.

METHODS

Timed urine collections and 09.00 hour plasma cortisol levels were obtained from 12 normal volunteers receiving inhaled placebo, beclomethasone (BDP) 800 or 2000 micrograms/day. The 24 hour urine samples were collected as follows: first hour after waking (hour 1), the next two hours after waking (hours 2 and 3), remainder of day, and overnight, with results expressed as urine cortisol/creatinine (UCC) ratios and as hourly cortisol output in the timed collections. Twenty four hour urinary cortisol excretion was also calculated. Medication was blinded and given in random order with a washout period of at least 11 days between each treatment arm.

RESULTS

None of the UCC ratios changed with BDP 800 micrograms/day. UCC ratios at hour 1, hour 2 and 3, and overnight, and 24 hour urinary free cortisol excretion were reduced after BDP 2000 micrograms/day, whilst remainder of day UCC ratio and the plasma cortisol level did not change significantly. Cortisol output showed similar changes. In a follow up study BDP 1400 micrograms/day also reduced UCC ratios for the first two hours after waking.

CONCLUSIONS

UCC ratios are as sensitive as the more cumbersome 24 hour urinary free cortisol excretion, and more sensitive than single morning plasma cortisol measurements, in detecting the effects of inhaled beclomethasone on the HPA axis.

Long-term bone loss after renal transplantation: comparison of immunosuppressive regimens

Serial measurements of serum and urine markers of bone metabolism and of forearm bone density (BMD) by dual photon absorptiometry were performed in 22 patients undergoing renal transplantation in 1986. Patients were randomised to immunosuppression with (1) cyclosporin alone (CsA group, n = 10), (2) cyclosporin for 3 months followed by azathioprine-prednisone (CsA/AzP group, n = 3) or (3) long-term azathioprine-prednisone (LT AzP group, n = 9). As no reduction in bone mineral density (BMD) was noted in the first 6 months, groups 2 and 3 were considered together (AzP group, n = 12). Mean +/- SEM BMD fell by 19 +/- 2% at 36 months (n = 19, p < 0.01), with similar reductions seen in the CsA and AzP groups. At 60 months, BMD of the AzP group was 25 +/- 3% below baseline (p < 0.01), while the CsA group were only 5 +/- 4% below baseline (p = NS vs baseline, p < 0.05 vs AzP group). The degree of reduction in BMD over 5 years correlated with total glucocorticoid dose (r = 0.63, p < 0.05), but not with biochemical markers of bone turnover. Serum alkaline phosphatase fell post-transplant in patients treated with AzP, but not in the CsA group. These results demonstrate significant loss of forearm bone mineral with long-term follow-up after renal transplantation, but suggest that patients treated with cyclosporin monotherapy may be at lower risk of this complication.

Intrahepatic cholestasis of pregnancy, worsening after dexamethasone

We present a case of intrahepatic cholestasis of pregnancy (ICP) treated with dexamethasone. Rapid elevation in transaminases was observed, beyond levels usually reported in this condition. The world literature is reviewed, with particular reference to a recently suggested treatment protocol using dexamethasone.

Chronic sulfonylurea therapy augments basal and meal-stimulated insulin secretion while attenuating insulin responses to sulfonylurea per se

OBJECTIVE

To examine changes in glycemia and insulin secretion in response to SU per se and in response to a standard diet plus OD or TD SU therapy during chronic GP and GB therapy.

RESEARCH DESIGN AND METHODS

Randomized (between agents and in order of dosing regimens), prospective, open, crossover study among 14 NIDDM patients to compare glucose, insulin, and C-peptide responses to a standard diet and to 10 mg of oral GP or GB taken without food 1) after 2 wk without therapy, 2) after 4 wk of either GP (n = 7) or GB (n = 7) treatment OD, and 3) after 4 wk of TD therapy with the same agent. Each patient received the same drug for maintenance therapy and for assessment of the response to the drug alone.

RESULTS

We observed a comparable reduction in overall glycemia with both agents, with more marked postprandial effects for GP. Similar glucose, insulin, and C-peptide profiles for both agents during OD and TD therapy. Augmented insulin secretion in response to meals contrasting with reduced insulinotropic effects of the drugs per se with chronic therapy.

CONCLUSIONS

Therapeutic equivalence of OD and TD dosing with GP and GB during chronic therapy. In view of the improved insulin secretion in response to nutrient stimuli, the attenuation of responses to SU per se during chronic therapy does not imply impairment of beta-cell secretory capacity or represent a therapeutic disadvantage.

Immunoreactive somatostatin in the rat ovary

Immunoreactive SRIH was detected in the rat ovary (15.6 pg/mg wet weight, 520 pg/mg protein) and was localized to the granulosa cells (168 +/- 6 pg/10(6) cells). Serial dilution studies showed parallelism of the inhibition curve for synthetic SRIH-14 and those of extracts of whole ovary and media conditioned by granulosa cells. The quantity of immunoreactive SRIH released into granulosa cell conditioned media decreased with time, while the intracellular content remained relatively constant. Gel chromatography showed peaks of immunoreactivity co-eluting with SRIH-14 (38%), SRIH-28 (31%) and a high molecular weight component. The addition of synthetic SRIH-14 stimulated meiotic maturation in cumulus-enclosed rat oocytes, with dose dependency being observed at SRIH-14 concentrations between 1 and 1000 pmol/l. No evidence of pre-pro-SRIH gene expression could be demonstrated in either rat ovary or testis using both Northern analysis and reverse transcriptase/polymerase chain reaction amplification of polyadenylated RNA. SRIH may be produced in the ovary during a specific stage of ontogeny or by an alternative gene. It is also possible that SRIH is actively taken up and stored by granulosa cells without being produced locally.

The effect of nasal hCT on bone turnover in Paget's disease of bone--implications for the treatment of other metabolic bone diseases

Thirty pagetic patients were treated for 6 months with a daily nasal application of 2 mg of synthetic human calcitonin (hCT). Serum alkaline phosphatases (SAP) and urinary hydroxyproline/creatinine ratio (OH/Cr), reflecting bone turnover, were significantly reduced from the first month of treatment (mean +/- SEM: SAP, -13.9 +/- 2.2%; OH/Cr, -22.2 +/- 5.8%; both P less than 0.01) and until the end of the 6-month course (mean +/- SEM: SAP, -29.7 +/- 4.6%; OH/Cr, -22.5 +/- 5.9%; both P less than 0.01). Nasal hCT was perfectly tolerated both locally and systemically. These results allow us to consider nasal hCT for long-term trials in metabolic bone diseases characterized by a relative increase of bone resorption.

Metformin increases insulin sensitivity and basal glucose clearance in type 2 (non-insulin dependent) diabetes mellitus

The effects of metformin on glycaemia, insulin and c-peptide levels, hepatic glucose production and insulin sensitivity (using the euglycaemic, hyperinsulinaemic clamp) were evaluated at fortnightly intervals in 9 Type 2 diabetic patients using a stepwise dosing protocol: Stage 1--no metformin for four weeks; stage 2--metformin 500mg mane; stage 3--metformin 500mg thrice daily; stage 4--metformin 1000mg thrice daily. Results are expressed as Mean +/- SEM. Fasting blood glucose decreased from basal values (9.7 +/- 1.0 mmol/L) by 13% at stage 2, 34% at stage 3 and 41% at stage 4 (p less than 0.02 vs basal for all stages; p less than 0.02 stage 2 vs stage 3). Post-prandial glycaemia was significantly improved only with metformin 3000mg/day (p less than 0.05). Fasting, meal-stimulated and total insulin and c-peptide levels showed no change. Hepatic glucose output did not change significantly with metformin. Insulin sensitivity, measured as total glucose utilisation during hyperinsulinaemia, increased from stage 1 (10.3 +/- 2.1 mumoL/kg/min) by 23% at stage 3 (p less than 0.05) and by 29% at stage 4 (p less than 0.02). Basal metabolic clearance of glucose increased compared to stage 1 (1.69 +/- 0.16 mL/kg/min) by 30% at stage 2, 53% at stage 3 and 44% at stage 4 (all p less than 0.02). This study demonstrates that improved efficiency of glucose utilisation, both basally and under conditions of euglycaemic hyperinsulinaemia, is the basis of metformin's antihyperglycaemic action.

Streptococcus pyogenes pneumonia with abscess formation

A 30-year-old female with mild asthma presented with high fever, hypotension, pleuritic chest pain, vomiting and diarrhea. Chest radiograph showed consolidation of the right upper lobe, and S. pyogenes was cultured from blood and sputum. Following initial rapid recovery the patient relapsed ten days after antibiotics were ceased, with rapid development of a large abscess cavity. Clinical improvement occurred following reinstitution of treatment including intravenous penicillin. Progressive radiological resolution eventuated during outpatient follow-up. This case demonstrates that S. pyogenes pneumonia may occur without an antecedent viral infection or major predisposing condition, cause rapid cavitation despite antiobiotic therapy and resolve satisfactorily with prolonged penicillin therapy.

Immobilization hypercalcaemia responding to intravenous pamidronate sodium therapy

A 16 year old male developed symptomatic hypercalcaemia of immobilization on day 47 following a diving accident which had resulted in incomplete C4 tetraplegia. Following initial reduction in serum calcium with salmon calcitonin 100 U/day, symptomatic hypercalcaemia recurred. A single dose of 30 mg pamidronate sodium, given intravenously, caused serum calcium to fall within 48 hours. Initial mild, asymptomatic hypocalcaemia was followed by a return to sustained normocalcaemia. No major adverse reaction was encountered, and if further clinical experience confirms its efficacy, pamidronate sodium will warrant consideration as first-line therapy for immobilization hypercalcaemia.