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

ABSTRACT 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.

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

ABSTRACT 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.

Recomendações da 2ª reunião do grupo de trabalho em diabetes e gravidez / Guidelines of the 2nd meeting of the diabetes and pregnancy task force

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 2ª 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 >/=110mg/dl ou glicemia de 2h >/=140mg/dl. São apresentadas também estratégias de manejo metabólico e obstétrico do diabetes gestacional e do diabetes pré-gestacional.

Diabetes melito: diagnóstico, classificaçäo e avaliaçäo do controle glicêmico / Diabetes mellitus: diagnosis, classification and glucose control evaluation

Diabetes e alteraçöes da tolerância à glicose säo freqüentes na populaçäo adulta e estäo associados a um aumento da mortalidade por doença cardiovascular e complicaçöes microvasculares. O diagnóstico destas situaçöes deve ser feito precocemente, utilizando métodos sensíveis e acurados, já que mudanças no estilo de vida e a correçäo da hiperglicemia podem retardar o aparecimento do diabetes ou de suas complicaçöes. 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 ingestäo de 75g de glicose for >/= 200mg/dl ou >/= 140 e <200mg/dl, respectivamente. Quando este teste näo puder ser realizado, utiliza-se a medida da glicose piasmática em jejum, considerando-se como diabetes ou glicose alterada em jejum quando os valores forem >/= 126mg/dl ou >/= 110 e <126mg/dl, respectivamente. A medida,da glico-hemoglobina näo deve ser utilizada para o diagnóstico, mas é o método de referência para avaliar o grau de controle glicémico a longo prazo. A classificaçäo 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 classificaçäo do paciente é usualmente feita em bases clínicas, mas a medida de auto-anticorpos e do peptídeo C pode ser útil em alguns casos.