The association between vitamin D receptor gene polymorphisms (TaqI and FokI), Type 2 diabetes, and micro-/macrovascular complications in postmenopausal women.

INTRODUCTION: Since there is evidence of the action of vitamin D as a modulator of insulin release and atherosclerosis, it may well be that the vitamin D receptor polymorphisms are associated with diabetes and its chronic complications. AIMS: To examine the associations between vitamin D receptor polymorphisms (FokI and TaqI) and Type 2 diabetes (T2DM) and its associated chronic complications in postmenopausal women. METHODS: This cross-sectional study analyzed 100 postmenopausal women with T2DM (mean age 65.7±7.18 years) and 100 postmenopausal women without diabetes in the control group (mean age 65.1±9.18 years; P=0.1608). We evaluated clinical and metabolic parameters and analyzed TaqI and FokI polymorphisms. RESULTS: There were no significant differences in genotype and allele frequencies between patients and controls in either of the polymorphisms studied. In the group of patients with diabetes, there were no significant differences in either polymorphism in relation to stroke, retinopathy, nephropathy, or neuropathy. However, in patients with T2DM and coronary artery disease, f genotype (P=0.0361) and the combination of Ff + ff genotypes were observed less frequently (P=0.0462). CONCLUSION: This study suggests the potential protective factor of FokI polymorphism for coronary artery disease in postmenopausal women with T2DM in the recessive model.

Assessment of a glycated hemoglobin point-of-care analyzer (A1CNow+) in comparison with an immunoturbidimetric method: a diagnostic accuracy study / Avaliação de um aparelho de diagnóstico local para hemoglobina glicada (A1CNow+) comparado com um método imunoturbidimétrico: estudo de acurácia de teste diagnóstico

CONTEXT AND OBJECTIVE: To monitor glycemic control in diabetic patients, regular measurement of glycated hemoglobin (HbA1c) is recommended, but this can be difficult in remote places without access to laboratories. Portable point-of-care testing devices can prove a useful alternative. Our study aimed to assess the performance of one of them: A1CNow+, from Bayer. DESIGN AND SETTING: Cross-sectional accuracy study conducted at a university hospital in Brazil. METHODS: We made three successive measurements of capillary HbA1c using the A1CNow+ in 55 diabetic volunteers, while the same measurement was made on venous blood using the hospital reference method (Vitros 5,1 FS). We used the Bland-Altman graphical method to assess the A1CNow+ in relation to the Vitros 5,1 FS method. We also evaluated clinical usefulness by calculating the sensitivity and specificity of A1CNow+ for detecting patients with HbA1c lower than 7%, which is the usual limit for good glycemic control. RESULTS: The coefficient of variation between repeat testing for the A1CNow+ was 3.6%. The mean difference between A1CNow+ and Vitros 5,1 FS was +0.67% (95% confidence interval, CI: +0.52 to +0.81). The agreement limits of our Bland-Altman graph were -0.45 (95% CI: -0.71 to -0.19) and +1.82 (95% CI: +1.52 to +2.05). The sensitivity and specificity in relation to the 7% limit were respectively 100% and 67.7%. CONCLUSIONS: Although the A1CNow+ had good sensitivity, its accuracy was insufficient for use as a replacement for laboratory measurements of HbA1c, for glycemic control monitoring in diabetic patients.

CONTEXTO E OBJETIVO: Para monitorar o controle glicêmico dos diabéticos, é recomendado medir regularmente a hemoglobina glicada (HbA1c). Isso pode ser difícil em locais distantes sem acesso a laboratórios. Uma alternativa é usar aparelhos portáteis à beira do leito do paciente. Nosso estudo visou avaliar o desempenho de um deles: A1CNow+, da Bayer. TIPO DE ESTUDO E LOCAL: Estudo transversal de acurácia realizado em hospital universitário no Brasil. MÉTODOS: Medimos, com o A1CNow+, três vezes seguidas, a HbA1c capilar de 55 diabéticos voluntários, enquanto a mesma medida era feita em sangue venoso pelo método de referência do hospital (Vitros 5,1 FS). Usamos a análise gráfica de Bland-Altman para avaliar o A1CNow+ em relação ao Vitros 5,1 FS. Verificamos a utilidade clínica através do cálculo da sensibilidade e da especificidade do A1CNow+ para detectar pacientes com HbA1c abaixo de 7%, limite usual indicando glicemia controlada. RESULTADOS: O coeficiente de variação entre testes repetidos do A1CNow+ foi de 3,6%. A diferença média entre o A1CNow+ e o Vitros 5,1 FS foi de +0,67% (95% intervalo de confiança, IC: +0,52 para +0,81). Os limites de concordância do gráfico de Bland-Altman foram -0,45 (95% IC: -0,71 para -0,19) and +1,82 (95% IC: +1,52 para +2,05). A sensibilidade e a especificidade em relação ao limite de 7% foram 100% e 67,7%, respectivamente. CONCLUSÃO: Apesar da boa sensibilidade, o A1CNow+ não tem acurácia suficiente para ser utilizado no monitoramento do controle glicêmico de pacientes diabéticos em substituição das medidas da HbA1c em laboratório.

Assessment of a glycated hemoglobin point-of-care analyzer (A1CNow+) in comparison with an immunoturbidimetric method: a diagnostic accuracy study.

CONTEXT AND OBJECTIVE: To monitor glycemic control in diabetic patients, regular measurement of glycated hemoglobin (HbA1c) is recommended, but this can be difficult in remote places without access to laboratories. Portable point-of-care testing devices can prove a useful alternative. Our study aimed to assess the performance of one of them: A1CNow+, from Bayer. DESIGN AND SETTING: Cross-sectional accuracy study conducted at a university hospital in Brazil. METHODS: We made three successive measurements of capillary HbA1c using the A1CNow+ in 55 diabetic volunteers, while the same measurement was made on venous blood using the hospital reference method (Vitros 5,1 FS). We used the Bland-Altman graphical method to assess the A1CNow+ in relation to the Vitros 5,1 FS method. We also evaluated clinical usefulness by calculating the sensitivity and specificity of A1CNow+ for detecting patients with HbA1c lower than 7%, which is the usual limit for good glycemic control. RESULTS: The coefficient of variation between repeat testing for the A1CNow+ was 3.6%. The mean difference between A1CNow+ and Vitros 5,1 FS was +0.67% (95% confidence interval, CI: +0.52 to +0.81). The agreement limits of our Bland-Altman graph were -0.45 (95% CI: -0.71 to -0.19) and +1.82 (95% CI: +1.52 to +2.05). The sensitivity and specificity in relation to the 7% limit were respectively 100% and 67.7%. CONCLUSIONS: Although the A1CNow+ had good sensitivity, its accuracy was insufficient for use as a replacement for laboratory measurements of HbA1c, for glycemic control monitoring in diabetic patients.

Vitamin D and diabetes mellitus: an update 2013.

Vitamin D deficiency and diabetes mellitus are two common conditions and they are widely prevalent across all ages, races, geographical regions, and socioeconomic conditions. Epidemiologic studies have shown association of vitamin D deficiency and increased risk of chronic diseases, such as cancer, cardiovascular disease, type 2 diabetes, and autoimmune diseases, such as multiple sclerosis and type 1 diabetes mellitus. The identification of 1,25(OH)2D receptors and 1-α-hydroxilase expression in pancreatic beta cells, in cells of the immune system, and in various others tissues, besides the bone system support the role of vitamin D in the pathogenesis of type 2 diabetes. Observational studies have revealed an association between 25(OH) D deficiency and the prevalence of type 1 diabetes in children and adolescents. This review will focus on the concept of vitamin D deficiency, its prevalence, and its role in the pathogenesis and risk of diabetes mellitus and cardiovascular diseases.

Vitamin D and diabetes mellitus: an update 2013 / Vitamin D e diabetes melito: uma atualização 2013

Vitamin D deficiency and diabetes mellitus are two common conditions and they are widely prevalent across all ages, races, geographical regions, and socioeconomic conditions. Epidemiologic studies have shown association of vitamin D deficiency and increased risk of chronic diseases, such as cancer, cardiovascular disease, type 2 diabetes, and autoimmune diseases, such as multiple sclerosis and type 1 diabetes mellitus. The identification of 1,25(OH)2D receptors and 1-α-hydroxilase expression in pancreatic beta cells, in cells of the immune system, and in various others tissues, besides the bone system support the role of vitamin D in the pathogenesis of type 2 diabetes. Observational studies have revealed an association between 25(OH) D deficiency and the prevalence of type 1 diabetes in children and adolescents. This review will focus on the concept of vitamin D deficiency, its prevalence, and its role in the pathogenesis and risk of diabetes mellitus and cardiovascular diseases.

A deficiência de vitamina D e o diabetes melito são enfermidades comuns na população e são altamente prevalentes em todas as raças, idades, regiões geográficas e situação socioeconômica. Estudos epidemiológicos mostram uma associação entre hipovitaminose D com o aumento do risco de doenças crônicas, tais como câncer, doença cardiovascular, diabetes melito do tipo 2 e doenças autoimunes como a esclerose múltipla e o diabetes mellitus do tipo 1. A identificação de receptores da 1,25(OH)2 D e da expressão da 1 α-hidroxilase nas células betapancreáticas, em células do sistema imunológico e em uma variedade de células do organismo além do tecido ósseo, suporta o papel da vitamina D na patogênese do diabetes tipo 2 e do tipo 1. Esta revisão apresenta e discute o conceito de deficiência de vitamina D, sua prevalência e seu papel na patogênese e no risco de desenvolvimento do diabetes melito e doenças cardiovasculares.

Deficiência de vitamina D em mulheres portadoras de diabetes mellitus tipo 2 na pós-menopausa / Vitamin D deficiency in postmenopausal women with type 2 diabetes mellitus

A descoberta de receptores para a forma ativa da vitamina D em células sem efeito direto no metabolismo ósseo e do cálcio tem ampliado o conceito do papel fisiológico desta molécula. O objetivo deste estudo foi determinar a associação entre a deficiência de vitamina D e o controle clínico e metabólico do diabetes mellitus e suas complicações crônicas. Foram estudadas 284 mulheres na pós-menopausa portadoras de diabetes mellitus tipo 2, atendidas no ambulatório da clínica endocrinológica do Hospital Agamenon Magalhães, Recife, Pernambuco, serviço de referência para diabéticos do Sistema Único de Saúde (SUS). Concentrações séricas da 25-OHD foram medidas e as pacientes foram agrupadas de acordo com os níveis séricos de 25 OHD < 20 ng/ml e menor ou igual a 20 ng/ml. A partir daí, foi feito a associação com as diversas variáveis do estudo. Foi considerado como deficiência de vitamina D, níveis séricos de 25 OHD abaixo de 20 ng/ml. A média da concentração sérica de 25-OHD foi de 25,60±8,51 e a percentagem de pacientes com níveis de 25 OHD abaixo 20 ng/ml foi de 24,6 por cento. Com exceção dos níveis séricos de triglicerídeos, não foi encontrada associação entre as concentrações de 25-OHD e o controle clínico e metabólico do diabetes mellitus. A média de 25-OHD foi significantemente menor nos sujeitos com retinopatia (23,29±8.0) que naqueles sem retinopatia (26,66±51), (p=0,002). Num modelo de regressão ajustado, níveis séricos baixos de 25-OHD (< 20 ng/ml) e fototipo de pele pigmentada, foi associado independentemente com a retinopatia. Não foi encontrada associação entre as concentrações de 25-OHD e doença arterial coronariana, amputação, acidente vascular cerebral, nefropatia e neuropatia

Em mulheres portadoras de diabetes tipo 2 na pós-menopausa, verificamos que a deficiência de vitamina D não se associou com o controle clínico e metabólico do diabetes mellitus, com exceção dos níveis de triglicerídeos. Entretanto, verificamos uma associação entre a deficiência de vitamina D, bem como o fototipo de pele pigmentada e a retinopatia diabética

Evidence-based non-skeletal actions of vitamin D.

Vitamin D is a major regulator of mineral homeostasis through its action in the kidney, intestine, bone and parathyroid glands. On these tissues, its active form, calcitriol, acts by binding to a specific nuclear receptor that belongs to the steroid/thyroid hormone receptor family. This receptor, however, has also been identified in several additional human tissues. So, apart from its traditional actions related to calcium, vitamin D and its synthetic analogs are being increasingly recognized for their anti-proliferative, pro-differentiative and immunomodulatory activities. Low levels of vitamin D have been linked to many chronic diseases. Decreased muscle function and increased fall risk in elderly people; prostate, breast and colorectal cancers; diabetes mellitus; and other health problems have been associated to low circulating levels of 25-hydroxyvitamin D. This paper presents an overview of the available scientific evidence for the non-calcemic actions of vitamin D in humans.

Evidence-based non-skeletal actions of vitamin D / Evidências das ações não esqueléticas da vitamina D

Vitamin D is a major regulator of mineral homeostasis through its action in the kidney, intestine, bone and parathyroid glands. On these tissues, its active form, calcitriol, acts by binding to a specific nuclear receptor that belongs to the steroid/thyroid hormone receptor family. This receptor, however, has also been identified in several additional human tissues. So, apart from its traditional actions related to calcium, vitamin D and its synthetic analogs are being increasingly recognized for their anti-proliferative, pro-differentiative and immunomodulatory activities. Low levels of vitamin D have been linked to many chronic diseases. Decreased muscle function and increased fall risk in elderly people; prostate, breast and colorectal cancers; diabetes mellitus; and other health problems have been associated to low circulating levels of 25-hydroxyvitamin D. This paper presents an overview of the available scientific evidence for the non-calcemic actions of vitamin D in humans.

A vitamina D é um importante regulador da homeostase mineral por meio de sua ação nos rins, no intestino, nos ossos e nas glândulas paratireoides. Nesses tecidos, sua forma ativa, o calcitriol, atua ligando-se a um receptor nuclear específico, pertencente à família de receptores dos hormônios esteroides e tireoidianos. Contudo, esse receptor também foi identificado em outros tecidos humanos. Assim, além de suas ações tradicionais, relacionadas ao metabolismo do cálcio, a vitamina D e análogos sintéticos estão, cada vez mais, sendo reconhecidos por seus efeitos antiproliferativos, pró-diferenciação e imunomodulatórios. Baixas concentrações séricas de vitamina D têm sido associadas a várias doenças crônicas. Redução da função muscular e aumento do risco de quedas em idosos; câncer de próstata, mama e colorretal; diabetes melito; e outros problemas de saúde têm sido associados a concentrações circulantes baixas de 25-hidroxivitamina D. Este trabalho apresenta uma visão geral sobre as evidências científicas disponíveis das ações não calcêmicas da vitamina D em humanos.