Angela de Azevedo Jacob Reichelt

Diabetes Melito: Diagnóstico, Classificação e Avaliação do Controle Glicêmico

Diabetes mellitus and other categories of impaired glucose tolerance are frequent in the adult population and are associated with an increased risk for cardiovascular disease and microvascular complications. The diagnosis of these entities should be performed early and using sensitive and accurate methods, since lifestyle changes and correction of hyperglycemia may delay the incidence of diabetes and its complications. Glucose tolerance test is the reference method and the diagnosis of diabetes and impaired glucose tolerance are established when the 2h plasma glucose after an oral intake of 75g of glucose is ³200mg/dl or ³140 and <200mg/dl, respectively. When it is not possible to perform this test, fasting plasma glucose levels ³126mg/dl or ³110 and <126mg/dl, respectively, are used to establish the diagnosis of diabetes and impaired fasting plasma glucose. Glycohemoglobin should not be used for the diagnosis but it is the reference method for evaluation of the long-term glucose control. The etiological classification of diabetes mellitus includes 4 categories: type 1 diabetes, type 2 diabetes, other specific types of diabetes and gestational diabetes. The assignment of the patient in each category usually is made on clinical grounds, however in some case the measurement of C-peptide and autoantibodies are necessary.

Fasting Plasma Glucose Is a Useful Test for the Detection of Gestational Diabetes

OBJECTIVE To evaluate fasting plasma glucose as a screening test for states of gestational diabetes. RESEARCH DESIGN AND METHODS Baseline data of a cohort conducted in general prenatal care units in Brazil, enrolling 5,579 women aged ≥ 20 years with gestational ages of 24–28 weeks at the time of testing and no previous diagnosis of diabetes. A standardized 2-h 75-g oral glucose tolerance test was performed in 5,010 women. Gestational diabetes and its subcategories—diabetes and impaired glucose tolerance—were defined according to the 1994 World Health Organization panel recommendations. We evaluated screening properties of calculated sensitivity and specificity for fasting plasma glucose with receiver operator characteristic curves. RESULTS For detection of the subcategory diabetes, a fasting plasma glucose of 89 mg/dl jointly maximizes sensitivity (88%) and specificity (78%), identifying 22% of the women as test-positive. For detection of impaired glucose tolerance, a value of 85 mg/dl jointly maximizes sensitivity and specificity (68%), identifying as test-positive 35% of the women. Lowering the cut point to 81 mg/dl increases sensitivity to 81%, but decreases specificity to 54%, labeling as test-positive 49% of the women. CONCLUSIONS Fasting plasma glucose is a useful test for the screening of both subcategories of gestational diabetes, a threshold of 85 mg/dl being an acceptable option. Effective screening for the subcategory diabetes can be achieved using a cut point of 89 mg/dl. If greater emphasis is placed on the detection of impaired glucose tolerance, a lower value, 81 mg/dl, may be needed.

Prevalence of gestational diabetes mellitus – do the new WHO criteria make a difference?

Aims To describe the prevalence of gestational diabetes mellitus (GDM) according to the 1998 WHO provisional recommendations and compare it to that found with previous 1985 WHO criteria.

Waist circumference and waist-to-hip ratio are related to gestational glucose tolerance

OBJECTIVE To evaluate the relationship of central fat distribution with gestational glucose tolerance during the usual time for screening gestational diabetes. RESEARCH DESIGN AND METHODS This cross-sectional study investigated 1,113 consecutive women, ≥ 20 years old, pregnant for ∼ 21 to 28 weeks, without history of previous diabetes outside pregnancy, who attended two general prenatal care units in Porto Alegre, Brazil, from 1991 to 1993. Weight, height, waist and hip circumferences, and skinfolds were measured, and a 2-h, 75-g glucose tolerance test was performed. Data were analyzed using multiple linear regression models. RESULTS Waist-to-hip ratio (WHR) and waist circumference were independently associated with higher 2-h glycemia. Glycemic level was 0.11 and 0.13 mmol/l greater for each standard deviation increase in WHR (0.06) and waist circumference (8.0 cm), respectively (P < 0.02). Restricting analyses to the subset of women with uterine height ≤ 26 cm improved the association (0.13 and 0.19 mmol/l, respectively, P < 0.02); differences of 0.22 and 0.19 mmol/l were observed for 1 SD changes in the sum of skinfold thicknesses (24.7 mm) and in age (5.5 years), respectively. CONCLUSIONS Central fat distribution measured in pregnancy is an independent predictor of gestational glucose intolerance. This finding supports the concept that NIDDM and gestational diabetes are parts of the same disease, differing basically in their moment of detection. The usefulness of these anthropometric measurements in identifying pregnant women at high risk of having gestational glucose intolerance merits further investigation.

Recomendações da 2ª. Reunião do Grupo de Trabalho em Diabetes e Gravidez

Clinical guidelines for the management of gestational and pre-gestational diabetes were prepared by the Diabetes and Pregnancy Task Force, during the XI Brazilian Diabetes Congress, held in 1997. A new meeting was held in 2001 to revise recommendations for screening, diagnosis and management of gestational diabetes, based on the new evidences generated on these issues. Universal screening of pregnant women is advised beginning at the 20th week of gestation, using fasting plasma glucose. Cut points of 85mg/dl or 90mg/dl are used to classify a positive screening. A 75g oral glucose tolerance test is performed if the screening test is positive. The diagnostic cut points suggested to define glucose alterations are a fasting plasma glucose ³110mg/dl or a 2h plasma glucose ³140mg/dl. Endocrine and obstetric management of gestational diabetes as well as a review on pre-gestational diabetes management are also presented.

Variation in glucose tolerance with ambient temperature

Ambient temperature may affect venous glucose concentration after glucose tolerance tests. We analysed 1030 standardised 75 g tests. Although mean fasting values did not differ, post-load values did: adjusted mean 2 h glucose concentration was 1.03 mmol/L lower at lower (5-14 degrees C) than at higher (25-31 degrees C) temperatures (p < 0.001). The occurrence of abnormal glucose tolerance doubled on warmer days. The diagnostic accuracy of the glucose tolerance test showed clinically significant temperature-associated variation. These variations, if confirmed, call for temperature standardisation during glucose tolerance testing and/or alternative strategies for use when standardisation is not feasible.

Serum Vitamin D Insufficiency Is Related to Blood Pressure in Diabetic Pregnancy

BACKGROUND Vitamin D deficiency in pregnancy has been associated with an increased risk of preeclampsia. However, the association between serum vitamin D and blood pressure in pregnant women has been scarcely evaluated, particularly in women with a high risk of developing hypertensive disorders of pregnancy. We sought to evaluate the association between serum 25-hydroxyvitamin D and blood pressure in pregnant women with gestational diabetes mellitus (GDM). METHODS A cohort of 184 pregnant women with GDM was followed during the third trimester of pregnancy and early puerperium. Blood pressure was recorded in all prenatal visits, and serum vitamin D was measured by chemiluminescence immunoassay. Pearsons coefficients and multiple linear regressions were used to study predictors of blood pressure levels. RESULTS Women with vitamin D insufficiency (<30ng/mL; n = 159) had higher systolic and diastolic blood pressure than the remaining participants. In white women (n = 136), serum vitamin D levels presented a significant negative correlation with systolic blood pressure at the beginning (r = -0.268; P = 0.002) and at the end of the third trimester (r = -0.203; P = 0.02), and vitamin D significantly affected systolic blood pressure after adjusting for confounders. This was not observed in women of other ethnicities. CONCLUSIONS In this cohort of pregnant women with GDM, vitamin D insufficiency was associated with higher blood pressure, and in white women, serum vitamin D was an independent predictor of systolic blood pressure during pregnancy.

Diabetes gestacional: um algoritmo de tratamento multidisciplinar

Effective treatment of gestational diabetes is important as an attempt to avoid unfavorable maternal and fetal outcomes. The objective of this paper is to describe the available therapies to optimize gestational diabetes treatment and to suggest a multidisciplinary approach algorithm. Nutrition therapy is the first option for the majority of these pregnancies; light to moderate physical activity is recommended in the absence of obstetrical contraindications. Medical treatment is recommended if glycemic control is not achieved or if excessive fetal growth is detected by ultrasound. Insulin is the standard treatment although oral antidiabetic drugs have recently been considered an effective and safe option. The monitoring of gestational diabetes treatment includes capillary glucose measurements and evaluation of fetal abdominal circumference by ultrasound performed around the 28th gestational week.

Vitamin D Deficiency Increases the Risk of Adverse Neonatal Outcomes in Gestational Diabetes

Background Gestational diabetes mellitus (GDM) and vitamin D deficiency have been associated with increased risk of adverse perinatal outcomes but the consequences of both conditions simultaneously present in pregnancy have not yet been evaluated. Our objective was to study the influence of vitamin D deficiency in neonatal outcomes of pregnancies with GDM. Methods 184 pregnant women with GDM referred to specialized prenatal monitoring were included in this cohort and had blood sampled for 25-hydroxyvitamin D measurement. Vitamin D was measured by chemiluminescence and deficiency was defined as < 20 ng/mL. Participants were followed until puerperium and adverse neonatal outcomes were evaluated. Results Newborns of women with vitamin D deficiency had higher incidences of hospitalization in intensive care units (ICU) (32 vs 19%, P = 0.048), of hypoglycemia (any, 17.3 vs 7.1%, P = 0.039requiring ICU, 15.3 vs 3.6%, P = 0.008), and were more frequently small for gestational age (SGA) (17.3 vs 5.9%, P = 0.017). After adjustment, relative risk (RR) for hypoglycemia requiring ICU was 3.63 (95%CI 1.09–12.11) and for SGA was 4.32 (95%CI 1.75–10.66). The incidence of prematurity, jaundice and shoulder dystocia was no statistically different between groups. Conclusions In this cohort of pregnant women with GDM, vitamin D deficiency was associated with a major increase in the incidence of adverse neonatal outcomes such as SGA newborns and neonatal hypoglycemia.

Postpartum glucose tolerance status 6 to 12 weeks after gestational diabetes mellitus: a Brazilian cohort

OBJECTIVES The aims of this study were to estimate the local rate of postpartum diabetes screening after gestational diabetes mellitus (GDM) pregnancies, and to identify clinical variables associated with retesting rates and with the persistence of decreased glucose tolerance. SUBJECTS AND METHODS Prospective cohort of GDM women with prenatal delivery at a specialized center, from November 2009 to May 2012. All women were advised to schedule a 6 weeks postpartum 75-g oral glucose tolerance test (OGTT). RESULTS Of the 209 women included, 108 (51.7%) returned to be tested with fasting plasma glucose (n=14), OGTT (n=93) or random glucose (n=1). Return was associated with lower parity rate (2 vs. 3, p<0.001) and higher pregnancy 2-h OGTT (165 vs. 155 mg/dL, p=0.034), but not with socio-demographic characteristics. Four women (3.7%) had diabetes, 22 (20.4%) had impaired fasting glucose or impaired glucose tolerance. Persistent hyperglycemia was associated with a positive family history of diabetes (relative risk-RR 2.41, p=0.050), diagnostic 2-h OGTT in pregnancy (RR 1.01, p=0.045), insulin use during pregnancy (RR 2.37, p=0.014), and cesarean section (RR 2.61, p=0.015). CONCLUSIONS Even though postpartum abnormalities were frequent in GDM, rates of postpartum diabetes screening were undesirably low. As no specific clinical profile defines who will adhere to postpartum testing, it is essential to encourage all women to reevaluate their glucose status, particularly those with a family history of diabetes and more severe hyperglycemia.