Rationale for prevention and treatment of glucose-mediated macrosomia: a protocol for gestational diabetes

Turning the tide: type 2 diabetes trends in offspring of mothers with gestational diabetes mellitus

In this review, the thesis is presented that maternal hyperglycemia produces an overnourished, fat fetus. If the fetus has a predisposition for type 2 diabetes, then the fat deposition in the fetus is predominantly in the fetal visceral cavity. Visceral fat deposition is the origin of insulin resistance. The fat fetus begins life with its pancreatic output of insulin compromised. Thus, the stage is set for developing type 2 diabetes in its lifetime. This review supports the hypothesis that normalization of maternal nutrition and fucose will decrease the risk of type 2 diabetes.

Efficacy, safety and lack of immunogenicity of insulin aspart compared with regular human insulin for women with gestational diabetes mellitus

AIM

The efficacy and safety of insulin aspart (IAsp), a rapid-acting human insulin analogue, were compared with regular human insulin (HI) as the bolus component of basal-bolus therapy for subjects with gestational diabetes mellitus (GDM).

METHODS

In a randomized, parallel-group, open-labelled trial, 27 women with GDM (age 30.7 +/- 6.3 years, HbA(1c) < 7%) were randomized to receive IAsp (5 min before meal) or HI (30 min before meal). The trial period extended from diagnosis of GDM (18-28 weeks) to 6 weeks postpartum.

RESULTS

Both treatment groups maintained good overall glycaemic control during the study (beginning and end of study HbA(1c)< or = 6%). During the meal test, mean glucose at week 6 (IAsp 4.2 +/- 0.57 mmol/l, HI 4.8 +/- 0.86 mmol/l) was slightly lower than at week 0 (IAsp 4.9 +/- 0.59 mmol/l, HI 5.1 +/- 0.36 mmol/l). However, change from baseline values for average glucose (IAsp -1.09 +/- 0.54 mmol/l, HI -0.54 +/- 0.74 mmol/l; P = 0.003) and C-peptide (IAsp -0.50 +/- 0.67 nmol/l, HI -0.30 +/- 0.70 nmol/l; P = 0.027) were significantly lower after IAsp treatment than HI treatment. No major hypoglycaemic events were reported during the study. Cross-reacting insulin antibody binding increased slightly from baseline in both treatments groups (end of study: IAsp 2.1 +/- 5.4%, HI 6.4 +/- 13.9%), whereas antibodies specific to IAsp or HI remained relatively low (< 1% binding).

CONCLUSION

IAsp was more effective than HI in decreasing postprandial glucose concentrations. Duration of IAsp injection 5 min before a meal rather than 30 min prior to meals offers a more convenient therapy for subjects with GDM. Overall safety and effectiveness of IAsp were comparable to HI in pregnant women with GDM.

Dietary intake, weight gain, and birth outcomes of physically active pregnant women: a pilot study

Pregnant women have increased energy and nutrient needs. Exercise also increases energy and glucose demands. This pilot study examined whether women who were physically active during pregnancy met their dietary needs, gained weight adequately, avoided hypoglycemia, and had normal birth outcomes. Based on a convenience sample, 11 active women were studied from 18 weeks gestation to delivery. They exercised for 40 min at 70% VO2 peak, 3-4 times per week. Weekly measures included capillary blood glucose concentrations, body mass, and food records. Birth outcome measures included baby mass, length, and activity, pulse, grimace, appearance, and respiration (APGAR) scores. Our findings suggest that these subjects had lower average energy intake (8680 +/- 490 kJ/d) than recommended for the 2nd and 3rd trimesters (13,020 +/-185 kJ/d; 13,480 +/- 185 kJ/d, respectively, p < 0.0001). Protein requirements for pregnancy were exceeded. Average intakes of iron (19 +/- 2 mg/d) and folate (356 +/- 33 microg/d) were lower than Recommended Dietary Allowances (RDAs) (27 mg/d and 600 microg/d, respectively) and milk products consumed were less than the recommended daily servings. Four women gained less weight per week than recommended for pregnancy. No hypoglycemia occurred post-exercise. Birth outcome measures were within normal ranges. Comparative studies with a larger number of subjects are required to determine if active pregnant women have adequate nutrient intakes and weight gain.

Gestational diabetes and nutritional recommendations

The goals of medical nutrition therapy for gestational diabetes mellitus (GDM) are to meet the maternal and fetal nutritional needs, as well as to achieve and maintain optimal glycemic control. Nutrition requirements during pregnancy are similar for women with and without GDM. The American Diabetes Association and the American College of Obstetrics and Gynecology recommend nutrition therapy for GDM that emphasizes food choices to promote appropriate weight gain and normoglycemia without ketonuria, and moderate energy restriction for obese women. Current controversies in GDM nutrition therapy involve manipulation of dietary composition (amounts and types of carbohydrates and fats), gestational weight gain, and energy and carbohydrate restriction. Randomized controlled trials are needed to determine which dietary compositions and patterns promote normoglycemia as well as optimal maternal and infant outcomes. Until better evidence is available, nutrition therapy will remain a cornerstone of GDM management with potential benefits that cannot be fully realized in clinical practice.

Nutrition and pregnancy: the link between dietary intake and diabetes

Pregnancy is a time when serial metabolic changes in the mother are carefully regulated to provide optimum substrate to both mother and fetus. Subtle perturbations in maternal metabolism can have implications not only for the index pregnancy, but also for future generations. The literature provides evidence that maternal nutrition plays a major role in the destiny of the offspring. Both maternal malnutrition and overnutrition are associated with subsequent diabetes in the offspring. Pregnancy represents a window of opportunity for health care providers to change dietary patterns toward habits that will be healthier for the individual now, as well as impacting on the future. The challenge for clinicians is to provide nutritional information based on scientific evidence that facilitates the normalization of fetal nutrition, and thus minimize the risk that the child will develop diabetes.

The clinical impact of screening for gestational diabetes

Gestational diabetes mellitus (GDM) is defined as carbohydrate intolerance during pregnancy. In Denmark the health service offers selective screening for GDM, i.e., admission to an oral glucose tolerance test (OGTT) after pre-screening with interview for clinical risk factors for GDM, two capillary fasting blood glucose (cFBG) measurements and a urine test for glucosuria. The aim of the present study was to investigate the power of the pre-screening to identify GDM and the screening to predict adverse clinical outcome.

A retrospective investigation of pregnant women undergoing screening during 1998 at Vejle County Hospital, Denmark was undertaken. The two most frequent pre-screening criteria for OGTT were body-mass index (BMI) ≥ 27 kg/m

The frequency of complicated delivery was similar in GDM (58%) compared to non-GDM (56%). The best predictor of complicated delivery was a BMI with OR=1.50 (95% CI: 0.87 to 2.60) for BMI ≥ 27 kg/m

Screening cFBG of 4.1 mmol/l was unable to predict GDM and adverse outcome. Glucosuria was too rare to be effective as a screening tool. Pre-screening did not identify GDM. The best predictor of complicated delivery was a high BMI. The best predictor of foetal adverse outcome was cBG

Achieving Euglycaemia in Women with Gestational Diabetes Mellitus

Gestational diabetes mellitus is one of the major medical complications of pregnancy. Untreated, the mother and the unborn child may experience morbidity and fetal death may even occur. It is important to diagnose and treat all hyperglycaemia appearing during pregnancy. Ideally, a screening and diagnostic test that identified all women at risk for hyperglycaemia-associated complications would be employed in all pregnant women. Unfortunately, there is no such test available currently. The best alternative is to administer an oral glucose challenge test to all pregnant women and then apply the best strategies for interpretation. This article discusses the limitations of our present diagnostic tools and suggests an option for the clinician until the definitive test has been elucidated. In addition, this article outlines one dietary and management strategy that has been associated with an outcome of pregnancy that is similar to the outcome of pregnancies in healthy women. This strategy includes starting with a "euglycaemic" diet (comprising < 40% carbohydrates and > or =40% fat), which can then be individualised according to the patient's glucose levels. Appropriate exercise, such as arm ergometer training, may enhance the benefits of diet control. For patients who require insulin, if the fasting glucose level is >90 mg/dL or 5 mmol/L (whole blood capillary) then NPH insulin (insulin suspension isophane) should be given before bed, beginning with dosages of 0.2 U/kg/day. If the postprandial glucose level is elevated, pre-meal rapid-acting insulin should be prescribed, beginning with a dose of 1U per 10g of carbohydrates in the meal. If both the fasting and postprandial glucose levels are elevated, or if a woman's postprandial glucose levels can only be blunted if starvation ketosis occurs, a four-injections-per-day regimen should be prescribed. The latter can be based on combinations of NPH insulin and regular human insulin, timed to provide basal and meal-related insulin boluses. The total daily insulin dose for the four-injection regimen should be adjusted according to pregnant bodyweight and gestational week (0.7-1 U/kg/day); doses may need to be increased for the morbidly obese or when there is twin gestation. There is now some evidence that insulin lispro, other insulin analogues and oral antihyperglycaemic drugs may be beneficial in gestational diabetes, and more data on these agents are awaited with interest.

New and future diabetes therapies: are they safe during pregnancy?

Diabetes in pregnancy, whether the woman had diabetes prior to becoming pregnant or developed gestational diabetes, is associated with many complications and risks. In the first trimester, organogenesis can be disrupted by complications due to poor control of the mother's diabetes, leading to fetal malformations or perinatal mortality. Problems with glucose control in the remainder of the pregnancy can also have consequences for the child. These include macrosomia, shoulder dystocia, pre-eclampsia, hypoglycemia and an increased risk for obesity and diabetes in the future. Therefore, aggressive and prompt treatment of the high blood sugar levels, which cause these complications, is necessary. This review looks at the current treatments for pregnancies complicated by diabetes and evaluates the place of new and possible future treatments including diet, exercise, insulin, insulin analogs and oral and inhaled agents.