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A correta classificação do diabete melito (DM) permite o tratamento mais adequado e compreende quatro categorias: DM tipo 1; DM tipo 2; Outros tipos e Diabete Gestacional. Em alguns casos, pode ocorrer sobreposição de quadros, principalmente no DM que inicia no adulto jovem ou que se apresenta inicialmente com cetoacidose, intermediários ao DM 1 e DM 2. Assim, acréscimos ao sistema de classificação clássico têm sido propostos, avaliando a presença de autoimunidade (anticorpos) e a função de célula β (peptídeo-C) para definir mais precisamente os subtipos. O objetivo desta revisão foi de analisar o desempenho desses índices diagnósticos para a classificação do DM e descrever os subtipos em detalhe. Os anticorpos contra o pâncreas evidenciam a autoimunidade, sendo o anticorpo contra insulina o mais acurado antes dos 5 anos de idade e o anti-descarboxilase do ácido glutâmico para início da doença acima dos 20 anos, é esse o teste que permanece positivo por mais tempo. Já a medida do peptídeo-C avalia a reserva pancreática de insulina, e os métodos de estímulo mais usados são a medida após refeição ou após glucagon endovenoso. Valores de peptídeo-C < 1,5 ng/ml definem o paciente com função pancreática ausente, e acima desse valor, com função preservada. Combinando-se a presença de anticorpos (A+) dirigidos ao pâncreas e a sua capacidade secretória de insulina (β+), pode-se subdividir a classificação do DM em tipo 1A (A+β-) e 1B (A+ β-); e o DM tipo 2 em subgrupos de DM 2A (A+β+) e DM 2B (A-β+), o que permite uma classificação e tratamento mais precisos, além de abrir os horizontes para o entendimento da patogênese do DM.The right classification for diabetes mellitus (DM) allows a more adequate treatment and comprises four categories: type 1 DM, type 2 DM, other types, and gestational diabetes. In some cases, there might be a superposition of situations, especially with regard to the DM that initiates in the young adult or is initially presented with diabetic ketoacidosis intermediately to type 1 and 2 DM. Thus, additions to the classic classification system have been proposed as assessing the presence of autoimmunity (antibody) and b cell function (C-peptide) to precisely define the subtypes. The aim of this literature review was to analyze these diagnostic indexes’ performance in the DM classification and to describe subtypes with details. The antibodies against pancreas confirm autoimmunity, and the antibody against insulin is more accurate before 5 years old, while the anti-glutamic acid decarboxylase is more accurate after 20 years old, a test which remains positive for a longer period. The measurement of C-peptide evaluates the pancreatic insulin reserve, and the most largely used methods of stimulation are the measurement after meals or after intravenous glucagon. C-peptide values < 1.5 ng/ml define a patient with absent pancreatic function and, above this value, patients with preserved function. When the presence of antibodies (A+) directed to the pancreas is combined to its insulin secretion capability (β+), it is possible to subdivide DM’s classification in type 1A (A+β-) and 1B (A+β-); and type 2A (A+β+) and 2B (A-β+), which allows a more precise classification and treatment besides opening horizons for the understanding of DM pathogenesis.

A hipertensão arterial sistêmica (HAS) é um dos principais fatores de risco para a instalação e progressão das complicações crônicas do diabetes melito (DM) tipo 2. A medida da pressão arterial (PA) através da monitorização ambulatorial da PA (MAPA) apresenta melhor correlação com o desenvolvimento de lesões em órgãos-alvo do que a medida no consultório. Além disso, permite a avaliação de parâmetros pressóricos distintos como as médias das PAs sistólica e diastólica das 24 h, do dia e da noite, cargas pressóricas e ausência do descenso noturno, além da identificação de pacientes com HAS do avental branco e mascarada. Os pacientes com DM apresentam maiores médias de PA diurna e noturna do que os sem DM. Além disso, um terço do pacientes normotensos com DM tipo 2 apresentam HAS mascarada, que está associada a um aumento da albuminúria e da espessura das paredes do ventrículo esquerdo. Por outro lado, a prevalência e o efeito da HAS do avental branco nos pacientes com DM ainda não foram adequadamente avaliados. A determinação da ausência do descenso noturno da PA não acrescenta informação às medidas da PA nas 24 h, no dia ou na noite, mas a medida da PA noturna parece ser relevante na retinopatia do DM. Em conclusão, a determinação da PA através da MAPA é capaz de estratificar de forma mais adequada os pacientes em risco para o desenvolvimento das complicações crônicas do DM e tornou-se um instrumento indispensável para o controle efetivo da PA nestes pacientes.Hypertension is one of the main risk factors for the onset and progression of chronic complications in type 2 diabetes mellitus (DM). Ambulatory blood pressure (BP) monitoring (ABPM) provides a better correlation with target organ lesions than BP obtained in the office. Furthermore, it allows the evaluation of distinct BP parameters such as the 24-h, daytime and nighttime systolic and diastolic BP means, BP loads and the absence of nocturnal drop of BP, as well as the identification of white-coat and masked hypertension. DM patients have higher daytime and nighttime BP means than non-DM patients. In addition, one third of normotensive type 2 DM patients have masked hypertension, which is associated with an increase in albuminuria and in left ventricle wall thickness. On the other hand, the prevalence and effect of white-coat hypertension in type 2 DM patients have not yet been properly evaluated. The absence of nocturnal drop of BP does not add information to the 24 h, daytime or nighttime BP measurements, but the nighttime BP means seem to be relevant in DM retinopathy. In conclusion, BP determination by ABPM allows better patient risk stratification for the development of DM chronic complications and is an essential instrument for effective BP control in these patients.

The right classification for diabetes mellitus (DM) allows a more adequate treatment and comprises four categories: type 1 DM, type 2 DM, other types, and gestational diabetes. In some cases, there might be a superposition of situations, especially with regard to the DM that initiates in the young adult or is initially presented with diabetic ketoacidosis intermediately to type 1 and 2 DM. Thus, additions to the classic classification system have been proposed as assessing the presence of autoimmunity (antibody) and b cell function (C-peptide) to precisely define the subtypes. The aim of this literature review was to analyze these diagnostic indexes` performance in the DM classification and to describe subtypes with details. The antibodies against pancreas confirm autoimmunity, and the antibody against insulin is more accurate before 5 years old, while the anti-glutamic acid decarboxylase is more accurate after 20 years old, a test which remains positive for a longer period. The measurement of C-peptide evaluates the pancreatic insulin reserve, and the most largely used methods of stimulation are the measurement after meals or after intravenous glucagon. C-peptide values < 1.5 ng/ml define a patient with absent pancreatic function and, above this value, patients with preserved function. When the presence of antibodies (A+) directed to the pancreas is combined to its insulin secretion capability (β+), it is possible to subdivide DM`s classification in type 1A (A+β-) and 1B (A+β-); and type 2A (A+β+) and 2B (A-β+), which allows a more precise classification and treatment besides opening horizons for the understanding of DM pathogenesis.

Hypertension is one of the main risk factors for the onset and progression of chronic complications in type 2 diabetes mellitus (DM). Ambulatory blood pressure (BP) monitoring (ABPM) provides a better correlation with target organ lesions than BP obtained in the office. Furthermore, it allows the evaluation of distinct BP parameters such as the 24-h, daytime and nighttime systolic and diastolic BP means, BP loads and the absence of nocturnal drop of BP, as well as the identification of white-coat and masked hypertension. DM patients have higher daytime and nighttime BP means than non-DM patients. In addition, one third of normotensive type 2 DM patients have masked hypertension, which is associated with an increase in albuminuria and in left ventricle wall thickness. On the other hand, the prevalence and effect of white-coat hypertension in type 2 DM patients have not yet been properly evaluated. The absence of nocturnal drop of BP does not add information to the 24 h, daytime or nighttime BP measurements, but the nighttime BP means seem to be relevant in DM retinopathy. In conclusion, BP determination by ABPM allows better patient risk stratification for the development of DM chronic complications and is an essential instrument for effective BP control in these patients.