A Brazilian cohort of pregnant women with overt diabetes: analyses of risk factors using a machine learning technique

Objective

Pregnancy complicated by type 2 diabetes is rising, while data on type 2 diabetes first diagnosed in pregnancy (overt diabetes) are scarce. We aimed to describe the frequency and characteristics of pregnant women with overt diabetes, compare them to those with known pregestational diabetes, and evaluate the potential predictors for the diagnosis of overt diabetes.

Subjects and methods

A retrospective cohort study including all pregnant women with type 2 diabetes evaluated in two public hospitals in Porto Alegre, Brazil, from May 20, 2005, to June 30, 2021. Classic and obstetric factors associated with type 2 diabetes risk were compared between the two groups, using machine learning techniques and multivariable analysis with Poisson regression.

Results

Overt diabetes occurred in 33% (95% confidence interval: 29%-37%) of 646 women. Characteristics of women with known or unknown type 2 diabetes were similar; excessive weight was the most common risk factor, affecting ~90% of women. Age >30 years and positive family history of diabetes were inversely related to a diagnosis of overt diabetes, while previous delivery of a macrosomic baby behaved as a risk factor in younger multiparous women; previous gestational diabetes and chronic hypertension were not relevant risk factors.

Conclusion

Characteristics of women with overt diabetes are similar to those of women with pregestational diabetes. Classic risk factors for diabetes not included in current questionnaires can help identify women at risk of type 2 diabetes before they become pregnant.

Exploring the Gantt chart as a tool to highlight double report in case series published during the first wave of the COVID-19 pandemic

BACKGROUND

During the COVID-19 pandemic, some studies describing different aspects of the infection included very similar participants, rising suspicion about double reporting. We aimed to evaluate the Gantt chart as a tool to highlight possible double reporting. The chart is routinely used in business applications to depict tasks of a project, by plotting horizontal bars against time, showing their time span and overlaps.

METHODS

All case reports and case series of pregnant women with COVID-19, published by July 15, 2020, were included. Initial and final dates of participants' enrollment, country, city, hospital, and number of pregnancies were plotted in the Gantt chart. Bars stand for enrollment dates of each study, according to hospital and city, thus allowing comparisons.

RESULTS

We included 116 articles in the present analysis. The Gantt chart highlighted papers in which some participants were likely the same, thus allowing easier identification of double reporting of cases. Combining all information and pregnancy characteristics and outcomes helped to recognize duplications when the authors did not acknowledged the previous publication.

CONCLUSIONS

Unintended double reporting may occur, especially in exceptional times. The Gantt chart may help researchers to visually identify potential duplications, thus avoiding biased estimates in systematic reviews or meta-analysis.

A snapshot of the prevalence of endocrine disorders in pregnancies complicated by coronavirus disease 2019: A narrative review with meta-analysis

Background

Some maternal characteristics indicate worse prognosis in pregnant women with coronavirus disease 2019 (COVID‐19).

Objective

To describe the prevalence of endocrine disorders in pregnancies involving COVID‐19, and its impact on maternal outcomes.

Search strategy

Search terms were “pregnancy” and “COVID‐19”.

Selection

PubMed, Embase, medRxiv, and Cochrane worksheet from February to July 2020 were searched.

Data collection and analysis

Articles describing endocrine disorders in pregnancies with and without COVID‐19 involvement were considered. We performed meta‐analyses of prevalence using random‐effect models and estimated relative risk and 95% confidence intervals (CI) of maternal outcomes relative to presence of endocrine disorders.

Main results

Articles included (n = 141) were divided into three data sets: individual (119 articles, 356 women), case series (17 articles, 1064 women), and national registries (7 articles, 10 178 women). Prevalence of obesity ranged from 16% to 46% and hyperglycemia in pregnancy (HIP) ranged from 8% to 12%. In data set 1, HIP and obesity were risk factors for severe disease in crude and age‐adjusted models, although not for intensive care unit admission. In data from two national registries, risk of dying was 5.62 (95% CI 0.30–105.95) in women with diabetes and 2.26 (95% CI 1.03–4.96) in those with obesity.

Conclusion

Obesity and HIP were prevalent in pregnant women with severe COVID‐19.

In pregnant women with COVID‐19, obesity and hyperglycemia were prevalent and associated with adverse maternal outcomes.

Temporal changes in characteristics and outcomes among pregnant women with pre-gestational diabetes

OBJECTIVE

To evaluate pregnancy outcomes among women with pre-gestational diabetes.

METHODS

Retrospective analysis of pregnant women with type 1 or type 2 diabetes attending a university hospital in Brazil. Maternal characteristics and pregnancy outcomes were compared among deliveries between May 1, 2005, and December 31, 2010, and between January 1, 2011, and December 31, 2015. Risks were calculated by Poisson regression.

RESULTS

In total 220 women were included. Type 1 diabetes was more frequent in 2005-2010 than in 2011-2015, and type 2 diabetes was more frequent in 2011-2015 (P=0.005). History of macrosomia (P=0.011), hypertensive disorders of pregnancy (P=0.015), and pre-gestational excess weight (body mass index >25 kg/m² ; P=0.003) was more frequent in 2011-2015. For women with type 1 diabetes, pre-gestational weight (P=0.007) and glycated hemoglobin (P=0.026) were higher in 2011-2015. For women with type 2 diabetes, previous hypertensive disorders of pregnancy (P=0.032) were more prevalent and family history of diabetes (P<0.001) less prevalent in 2011-2015. Adverse pregnancy outcomes were similar for type 1 and type 2, and across both periods.

CONCLUSION

Type 2 diabetes became more common over the two time periods and women with type 1 diabetes had higher pre-gestational weight. Perinatal outcomes were similar.

Influence of maternal weight gain on birth weight: a gestational diabetes cohort

Objective Our objective was to evaluate gestational weight gain (GWG) patterns and their relation to birth weight. Subjects and methods We prospectively enrolled 474 women with gestational diabetes mellitus (GDM) at a university hospital (Porto Alegre, Brazil, November 2009-May 2015). GWG was categorized according to the 2009 Institute of Medicine guidelines; birth weight was classified as large (LGA) or small (SGA) for gestational age. Adjusted relative risks (aRRs) and 95% confidence intervals (95% CIs) were determined. Results Adequate GWG occurred in 121 women [25.5%, 95% CI: 22, 30%]; excessive, in 180 [38.0%, 95% CI: 34, 43%]; and insufficient, in 173 [36.5%, 95% CI: 32, 41%]. In women with normal body mass index (BMI), the prevalence of SGA was higher in those with insufficient compared to adequate GWG (30% vs. 0%, p < 0.001). In women with BMI ≥ 25 kg/m2, excessive GWG increased the prevalence of LGA [aRR 2.58, 95% CI: 1.06, 6.29] and protected from SGA [aRR 0.25, 95% CI: 0.10, 0.64]. Insufficient vs. adequate GWG did not influence the prevalence of SGA [aRR 0.61, 95% CI: 0.31, 1.22]; insufficient vs. excessive GWG protected from LGA [aRR 0.46, 95% CI: 0.23, 0.91]. Conclusions One quarter of this cohort achieved adequate GWG, indicating that specific ranges have to be tailored for GDM. To prevent inadequate birth weight, excessive GWG in women with higher BMI and less than recommended GWG in normal BMI women should be avoided; less than recommended GWG may be suitable for overweight and obese women.

Weight gain adequacy and pregnancy outcomes in gestational diabetes: a meta-analysis

The Institute of Medicine updated guidelines for gestational weight gain in 2009, with no special recommendations for gestational diabetes. Our objectives were to describe the prevalence of weight gain adequacy and their association with adverse pregnancy outcomes in gestational diabetes. We searched MEDLINE, EMBASE, COCHRANE and SCOPUS. We calculated the pooled prevalence of gain adequacy and relative risks for pregnancy outcomes within Institute of Medicine categories. Thirty-three studies/abstracts (88,599 women) were included. Thirty-one studies provided data on the prevalence of weight gain adequacy; it was adequate in 34% (95% CI: 29-39%) of women, insufficient in 30% (95% CI: 27-34%) and excessive in 37% (95% CI: 33-41%). Excessive gain was associated with increased risks of pharmacological treatment, hypertensive disorders of pregnancy, caesarean section, large for gestational age and macrosomic babies, compared to adequate or non-excessive gain. Weight gain below the guidance had a protective effect on large babies (RR: 0.71; 95% CI: 0.56-0.90) and macrosomia (RR 0.57; 95% CI 0.40-0.83), and did not increase the risk of small babies (RR 1.40; 95% CI 0.86-2.27). Less than recommended weight gain would be beneficial, while effective prevention of excessive gain is of utmost importance, in gestational diabetes pregnancies. Nevertheless, no ideal range for weight gain could be established.

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. Pearson's 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.

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

O Grupo de Trabalho em Diabetes e Gravidez, reunido durante o XI Congresso Brasileiro de Diabetes em 1997, elaborou normas para o manejo do diabetes gestacional e pré-gestacional. Em 2001, nova reunião ocorreu visando atualizar os posicionamentos assumidos em 1997, a partir de novas evidências da literatura. As mudanças sugeridas estão incorporadas no documento a seguir. O rastreamento do diabetes gestacional deve ser universal e, para isso, é sugerido o emprego da glicemia de jejum a partir da 20ª semana de gestação. Os pontos de corte para classificação de rastreamento positivo são 85mg/dl ou 90mg/dl; nos casos de rastreamento positivo, o exame recomendado é o teste oral de tolerância com 75g de glicose e os critérios para o diagnóstico do diabetes gestacional são glicemia de jejum > ou = 110mg/dl ou glicemia de 2h > ou = 140mg/dl. São apresentadas também estratégias de manejo metabólico e obstétrico do diabetes gestacional e do diabetes pré-gestacional.

Total sialic acid and associated elements of the metabolic syndrome in women with and without previous gestational diabetes

OBJECTIVE

Inflammatory markers predict type 2 diabetes and relate to the metabolic syndrome. Gestational diabetes mellitus (GDM) predicts type 2 diabetes and may be part of this syndrome. To examine the association of inflammatory markers with GDM, we investigated total sialic acid (TSA) in women with and without previous GDM.

RESEARCH DESIGN AND METHODS

All women with GDM and a random sample of women from one center of the Brazilian Study of Gestational Diabetes were invited to return 7 years after their index pregnancy. After an interview, an oral glucose tolerance test and anthropometry were performed. A total of 46 women with and 50 women without previous GDM completed the protocol.

RESULTS

Mean TSA was significantly higher in women with (71.8 +/- 11.1 mg/dl) than without (67.5 +/- 9.8 mg/dl) previous GDM (P < 0.05). In a linear regression model, TSA was 4 mg/dl (P < 0.05) higher in women with previous GDM, after adjustment for BMI, fasting insulin sensitivity, and number of years spent in school. In a similar model, current 2-h plasma glucose levels were associated with higher TSA levels after adjustment for waist-to-hip ratio and the log of triglycerides. TSA was strongly correlated with individual components and aggregates (r = 0.55, P < 0.001) of the metabolic syndrome.

CONCLUSIONS

Increased TSA levels are associated with previous GDM and are strongly linked to the metabolic syndrome. These findings in young women suggest that a chronic mild systemic inflammatory response is an early feature of the metabolic syndrome and that GDM may be a window for its investigation.

Diabetes Melito: Diagnóstico, Classificação e Avaliação do Controle Glicêmico

Diabetes e alterações da tolerância à glicose são freqüentes na população adulta e estão associados a um aumento da mortalidade por doença cardiovascular e complicações microvasculares. O diagnóstico destas situações deve ser feito precocemente, utilizando métodos sensíveis e acurados, já que mudanças no estilo de vida e a correção da hiperglicemia podem retardar o aparecimento do diabetes ou de suas complicações. O teste oral de tolerância à glicose é o método de referência, considerando-se a presença de diabetes ou tolerância à glicose diminuída quando a glicose plasmática de 2h após a ingestão de 75g de glicose for > ou = 200mg/dl ou > ou = 140 e <200mg/dl, respectivamente. Quando este teste não puder ser realizado, utiliza-se a medida da glicose plasmática em jejum, considerando-se como diabetes ou glicose alterada em jejum quando os valores forem > ou = 126mg/dl ou > ou = 110 e <126mg/dl, respectivamente. A medida da glico-hemoglobina não deve ser utilizada para o diagnóstico, mas é o método de referência para avaliar o grau de controle glicêmico a longo prazo. A classificação etiológica proposta atualmente para o diabetes melito inclui 4 categorias: diabetes melito tipo 1, diabetes melito tipo 2, outros tipos específicos de diabetes e diabetes gestacional. A classificação do paciente é usualmente feita em bases clínicas, mas a medida de auto-anticorpos e do peptídeo C pode ser útil em alguns casos.

Gestational diabetes mellitus diagnosed with a 2-h 75-g oral glucose tolerance test and adverse pregnancy outcomes

OBJECTIVE

To evaluate American Diabetes Association (ADA) and World Health Organization (WHO) diagnostic criteria for gestational diabetes mellitus (GDM) against pregnancy outcomes.

RESEARCH DESIGN AND METHODS

This cohort study consecutively enrolled Brazilian adult women attending general prenatal clinics. All women were requested to undertake a standardized 2-h 75-g oral glucose tolerance test (OGTT) between their estimated 24th and 28th gestational weeks and were then followed to delivery. New ADA criteria for GDM require two plasma glucose values > or = 5.3 mmol/l (fasting), > or = 10 mmol/l (1 h), and > or = 8.6 mmol/l (2 h). WHO criteria require a plasma glucose > or = 7.0 mmol/l (fasting) or > or = 7.8 mmol/l (2 h). Individuals with hyperglycemia indicative of diabetes outside of pregnancy were excluded.

RESULTS

Among the 4,977 women studied, 2.4% (95% CI 2.0-2.9) presented with GDM by ADA criteria and 7.2% (6.5-7.9) by WHO criteria. After adjustment for the effects of age, obesity, and other risk factors, GDM by ADA criteria predicted an increased risk of macrosomia (RR 1.29, 95% CI 0.73-2.18), preeclampsia (2.28, 1.22-4.16), and perinatal death (3.10, 1.42-6.47). Similarly, GDM by WHO criteria predicted increased risk for macrosomia (1.45, 1.06-1.95), preeclampsia (1.94, 1.22-3.03), and perinatal death (1.59, 0.86-2.90). Of women positive by WHO criteria, 260 (73%) were negative by ADA criteria. Conversely, 22 (18%) women positive by ADA criteria were negative by WHO criteria.

CONCLUSIONS

GDM based on a 2-h 75-g OGTT defined by either WHO or ADA criteria predicts adverse pregnancy outcomes.

Prevalence of gestational diabetes mellitus--do the new WHO criteria make a difference? Brazilian Gestational Diabetes Study Group

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.

METHODS

A total of 5564 consecutive women aged 20 years or more without diagnosis of diabetes mellitus outside of pregnancy in general prenatal care clinics of the National Health Service in 6 state capitals of Brazil, between their 20th and 28th gestational weeks were enrolled.

RESULTS

Of the 5004 women who completed a 75-g oral glucose tolerance test, 379 (7.6%, 95% confidence interval (CI) 6.9% to 8.4%) had GDM by the 1998 criteria (fasting glucose > or = 7.0 mmol/l or 2 h glucose > or = 7.8 mmol/l). Of these 379 cases, only 21 (5.5%) had hyperglycaemia in the range considered diabetes mellitus outside pregnancy (fasting glucose > or = 7.0 mmol/l or 2 h glucose > or = 11.1 mmol/l); the remaining 358 (94.5%) had hyperglycaemia in the impaired glucose tolerance range (fasting glucose < 7.0 and 2 h glucose > or = 7.8 mmol/l and < 11.1 mmol/l). Using the 1985 criteria (fasting or 2 h glucose > or = 7.8 mmol/l), 378 cases of GDM were found, 15 in the diabetes range and 363 in the impaired glucose tolerance range.

CONCLUSIONS

Prevalence of GDM is minimally altered by the new WHO definition. Although GDM is a common condition, the vast majority of the cases have hyperglycaemia in the range considered impaired glucose tolerance outside pregnancy.

Consenso sobre diabetes gestacional e diabetes pré-gestacional

O Grupo de Trabalho em Diabetes e Gravidez, reunido durante o XI Congresso Brasileiro de Diabetes, em 1997, elaborou normas para o manejo do diabetes gestacional e pré-gestacional. O rastreamento do diabetes gestacional deve ser seletivo, isto é, dirigido a gestantes com fatores de risco. Para tanto, é sugerido o emprego da glicemia de jejum a partir da 20ª semana de gestação. Pontos de corte de 85mg/dl ou 90mg/dl são sugeridos para classificação de rastreamento positivo, que indica a necessidade de um teste oral de tolerância com 75g de glicose. Esse teste deve ser interpretado de acordo com os critérios sugeridos pela Organização Mundial da Saúde (glicemia de jejum ³126mg/dl ou glicemia de 2h ³140mg/dl). São apresentadas também estratégias de manejo metabólico e obstétrico do diabetes gestacional e do diabetes pré-gestacional.

Fasting plasma glucose is a useful test for the detection of gestational diabetes. Brazilian Study of Gestational Diabetes (EBDG) Working Group

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 > or = 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.

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, > or = 20 years old, pregnant for approximately 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 < or = 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.

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.