Gestational diabetes: costs and consequences

Glucose challenge test (50-g GCT) in detection of glucose metabolism disorders in peritoneal dialysis patients: preliminary study

BACKGROUND

The aim was to evaluate the clinical utility of the oral glucose tolerance screening test (50-g GCT--glucose challenge test) for the detection of glucose metabolism disorders (GMD) in peritoneal dialysis (PD) patients with normal fasting glucose levels.

METHODS

The 50-g GCT was performed in 20 prevalent patients without history of diabetes before PD treatment onset, who had been on dialysis for a median time of 15.34 months. In addition, other indicators of glucose metabolism were measured: C-peptide, fasting insulin serum concentration, and the glycated hemoglobin level (HbA1c). The patients were prospectively followed for a median time of 25.8 months.

RESULTS

50-g GCT revealed GMD in 15 studied patients (75%)--impaired glucose tolerance in 11 patients (55%) and diabetes mellitus in four patients (20%). HbA1c and insulin resistance, estimated by homeostasis model assessment, were elevated in two (10%) and seven (35%) patients, respectively. In patients with GMD, dietetic and pharmacologic interventions were performed. When the 50-g GCT was repeated at the end of the observation period, 12 (60%) patients reported GMD, with no case of diabetes.

CONCLUSION

50-g GCT appears to be a simple and practical tool for the detection of GMD in PD patients with normal fasting glucose. Timely therapeutic intervention can effectively inhibit the progression of glucose intolerance during PD treatment.

Postpartum care for Aboriginal and non-Aboriginal women with Gestational Diabetes Mellitus across urban, rural and remote locations: a protocol for a cohort linkage study

BACKGROUND

Gestational diabetes mellitus (GDM) is increasing, along with obesity and type 2 diabetes (T2DM), with Aboriginal and Torres Strait Islander (Aboriginal(a)) women in Australia particularly affected. GDM causes serious complications in pregnancy, birth, and the longer term, for women and their infants. Women with GDM have an eightfold risk of developing T2DM after pregnancy, compared to women without GDM. Indigenous women have an even higher risk, at a younger age, and progress more quickly from GDM to T2DM, compared to non-Indigenous women. If left undetected and untreated, T2DM increases risks in subsequent pregnancies, and can lead to heart disease, stroke, kidney failure, limb amputations and blindness for the woman in the longer term. A GDM diagnosis offers a 'window of opportunity' to provide acceptable and effective prevention, treatment, and postpartum care. Low rates of postpartum T2DM screening are reported among non-Aboriginal women in Australia and Indigenous women in other countries, however, data for Aboriginal women in Australia are scarce. A healthy diet, exercise and breastfeeding can delay the onset of T2DM, and together with T2DM screening are recommended elements of postpartum care for women with GDM. This paper describes methods for a study evaluating postpartum care among Aboriginal and non-Aboriginal women with GDM.

METHODS/DESIGN

This retrospective cohort includes all women who gave birth at Cairns Hospital in far north Queensland, Australia, from 2004 to 2010, coded as having GDM in the Cairns Hospital Clinical Coding system. Data is being linked with the Midwives Perinatal Data Collection, and the three local laboratories. Hospital medical records are being reviewed to validate accuracy of GDM case ascertainment, and gather information on breastfeeding and provision of dietary advice. Survival analysis is being used to estimate time to screening, and rates of progression from GDM to T2DM. Logistic regression is being used to compare postpartum care between Aboriginal and non-Aboriginal women, and assess factors that may be associated with provision of postpartum care.

DISCUSSION

There are challenges to collecting postpartum data for women with GDM, however, this research is urgently needed to ensure adequate postpartum care is provided for women with GDM.

The lipid accumulation product for the early prediction of gestational insulin resistance and glucose dysregulation

BACKGROUND

Recent insights linking insulin resistance and lipid overaccumulation suggest a novel approach for the early identification of women who may soon experience glucose dysregulation. Among women without a history of gestational diabetes, we tested the association between the lipid accumulation product (LAP) obtained in early pregnancy and glucose dysregulation or insulin resistance in the second trimester.

METHODS

A total of 180 white pregnant women of French-Canadian origin were included in this study. At 11–14 weeks' gestation, fasting insulin, glucose, C-peptide concentrations, and estimated insulin resistance (HOMA-IR) were obtained. The waist circumference (WC) and fasting triglycerides (TG) were measured to calculate LAP as(WC[cm] - 58) · TG[mmol/L]. At 24–28 weeks' gestation, glucose was measured 2 hours after a 75-g oral glucose challenge and other fasting variables were repeated.

RESULTS

Among the nulliparous women tested at the end of the second trimester, fasting insulin, C-peptide, insulin resistance (HOMA-IR index), fasting glucose, and 2-hour glucose progressively increased ( p £ 0.002)according to their first-trimester LAP tertiles. Similar results were observed in parous women except for the glucose variables. The first-trimester LAP tended to show a stronger correlation to the second-trimester HOMAIR index (r = 0.56) than fasting triglyceride levels alone (r = 0.40) or waist circumference alone (r = 0.44) among nulliparous women. Similar associations were observed for parous women. Adjustment for body mass index weakened these associations, especially among parous women.

CONCLUSIONS

An increased value of LAP at the beginning of a pregnancy could be associated with an increased risk of insulin resistance or hyperglycemia later in gestation.

Diabetes in pregnancy among indigenous women in Australia, Canada, New Zealand and the United States

Recently proposed international guidelines for screening for gestational diabetes mellitus (GDM) recommend additional screening in early pregnancy for sub-populations at a high risk of type 2 diabetes mellitus (T2DM), such as indigenous women. However, there are criteria that should be met to ensure the benefits outweigh the risks of population-based screening. This review examines the published evidence for early screening for indigenous women as related to these criteria. Any publications were included that referred to diabetes in pregnancy among indigenous women in Australia, Canada, New Zealand and the United States (n = 145). The risk of bias was appraised. There is sufficient evidence describing the epidemiology of diabetes in pregnancy, demonstrating that it imposes a significant disease burden on indigenous women and their infants at birth and across the lifecourse (n = 120 studies). Women with pre-existing T2DM have a higher risk than women who develop GDM during pregnancy. However, there was insufficient evidence to address the remaining five criteria, including the following: understanding current screening practice and rates (n = 7); acceptability of GDM screening (n = 0); efficacy and cost of screening for GDM (n = 3); availability of effective treatment after diagnosis (n = 6); and effective systems for follow-up after pregnancy (n = 5). Given the impact of diabetes in pregnancy, particularly undiagnosed T2DM, GDM screening in early pregnancy offers potential benefits for indigenous women. However, researchers, policy makers and clinicians must work together with communities to develop effective strategies for implementation and minimizing the potential risks. Evidence of effective strategies for primary prevention, GDM treatment and follow-up after pregnancy are urgently needed.

Gestational diabetes mellitus

Gestational diabetes mellitus (GDM) represents a heterogeneous group of metabolic disorders, which result in varying degrees of maternal hyperglycemia and pregnancy-associated risk. The frequency of GDM is rising globally and may also increase further as less-stringent criteria for the diagnosis are potentially adopted. The additional burden placed on the health care system by increasing cases of GDM requires consideration of diagnostic approaches and currently used treatment strategies. Debate continues to surround both the diagnosis and treatment of GDM despite several recent large-scale studies addressing these controversial issues. As many now have come to reassess their approach to the management of GDM, we provide information in this review to help guide this process. The goal for each health care practitioner should continue to be to provide optimum care for women discovered to have carbohydrate intolerance during pregnancy.

Proposed new diagnostic criteria for gestational diabetes--a pause for thought?

New criteria for the diagnosis of gestational diabetes promulgated by the International Association of Diabetes and Pregnancy Study Groups (IADSPG) have been adopted by a number of groups, including the American Diabetes Association. These criteria will increase two- to three-fold the number of women diagnosed with gestational diabetes and have enormous resource implications. The recommendations are derived from observations made in the Hyperglycemia and Adverse Pregnancy Outcomes (HAPO) study, which demonstrated continuous relationships between maternal glucose tolerance and two clinically relevant outcomes of pregnancy (caesarean section rate and neonatal hypoglycaemia) and two surrogate measures (birth weight and cord C-peptide). The recent randomized intervention studies in mild gestational diabetes indicate that the major effects of detecting and treating mild gestational diabetes are a reduction in mean birthweight of 100-140 g, and a reduction in the incidence of shoulder dystocia. However, the women included in these studies were identified using different diagnostic criteria, and it cannot be assumed that women diagnosed by the less stringent IADSPG criteria will have the same benefit. Moreover, as the majority of cases of macrosomia and shoulder dystocia occur in women with normal glucose tolerance, the real impact of diagnosing many more 'cases' of gestational diabetes is likely to be minimal. The concentration on mild degrees of hyperglycaemia may well be misplaced, as most of the outcomes usually attributed to gestational diabetes are more strongly associated with maternal obesity and weight gain in pregnancy. The new testing procedure (with diagnosis based on a single blood glucose measurement) will inevitably be imprecise. Given the many reservations about the new criteria an urgent but dispassionate debate is required on the risks, costs and benefits of their introduction.