Glycemic Changes Related to Arsenic Exposure: An Overview of Animal and Human Studies.

BACKGROUND: Arsenic (As) is a risk factor associated with glycemic alterations. However, the mechanisms of action and metabolic aspects associated with changes in glycemic profiles have not yet been completely elucidated. Therefore, in this review, we aimed to investigate the metabolic aspects of As and its mechanism of action associated with glycemic changes. METHODS: We searched the PubMed (MEDLINE) and Google Scholar databases for relevant articles published in English. A combination of free text and medical subject heading keywords and search terms was used to construct search equations. The search yielded 466 articles; however, only 50 were included in the review. RESULTS: We observed that the relationship between As exposure and glycemic alterations in humans may be associated with sex, smoking status, body mass index, age, occupation, and genetic factors. The main mechanisms of action associated with changes induced by exposure to As in the glycemic profile identified in animals are increased oxidative stress, reduced expression of glucose transporter type 4, induction of inflammatory factor expression and dysfunction of pancreatic ß cells. CONCLUSIONS: Therefore, As exposure may be associated with glycemic alterations according to inter-individual differences.

Associations between Components of Metabolic Syndrome and Demographic, Nutritional, and Lifestyle Factors.

Objectives: To evaluate the associations between individuals with and without changes in components of metabolic syndrome (MetS) and demographic, nutritional, and lifestyle factors. Methods: A cross-sectional study was conducted with 224 individuals followed-up at a public hospital in Northeast Brazil. We used National Cholesterol Education Program-Adult Treatment Panel III (NCEP) criteria to diagnose MetS. We assessed components of MetS as dependent variables, while sex, age, food consumption, smoking, alcohol intake, physical activity, anthropometric parameters, and sleep hours were independent variables. Results: Comparing individuals with and without changes in components of MetS, the logistic regression models revealed that female sex was predictive of increased waist circumference and low HDL-c levels while advanced age was predictive of increased blood pressure and blood glucose levels. BMI emerged as a predictor for waist circumference and a protective factor for triglyceride levels. In addition, potassium intake, physical activity, and sleep duration were protective against decreased HDL-c, elevated triglyceride, and elevated blood pressure levels, respectively. Conclusion: This study demonstrated that sex, age, BMI, dietary potassium intake, physical activity, and hours of sleep are factors to be targeted in public health actions for prevention and treatment of MetS.

Status de vitamina D e risco cardiovascular em indivíduos com síndrome metabólica / Vitamin D status and cardiovascular risk in individuals with metabolic syndrome

Introdução: A síndrome metabólica é um conjunto de desordens metabólicas, consideradas fatores de risco cardiovascular. Estima-se que indivíduos com síndrome metabólica apresentam probabilidade três vezes maior de desenvolver doenças cardiovasculares. O status inadequado de vitamina D tem apresentado múltiplos mecanismos fisiopatológicos que sugerem um envolvimento no desenvolvimento de doenças cardiovasculares. Objetivo: avaliar a associação entre o status de vitamina D e o risco de doenças cardiovasculares em indivíduos com síndrome metabólica. Métodos: Estudo do tipo transversal realizado com 161 indivíduos adultos, diagnosticados com síndrome metabólica. Foram realizadas as medidas antropométricas, pressão arterial, e as análises bioquímicas, incluindo a dosagem de 25(OH)D no soro. O critério estabelecido para classificação do status de 25(OH)D foi deficiente < 20 ng/mL; insuficiente≤ 29 ng/mL e suficiente ≥ 30 ng/mL. Ademais, avaliou-se o risco absoluto de desenvolver doenças cardiovasculares usando o Escore de Risco de Framingham. Resultados: A mediana da concentração de 25(OH)D foi 29,7 (21-34) ng/mL, indicando status de 25(OH)D insuficiente na população. Não houve associação entre status de vitamina D e o risco cardiovascular em indivíduos com síndrome metabólica (p > 0,05). Conclusão: Não se observou associação entre status 25(OH)D inadequado e maior risco cardiovascular nos indivíduos com síndrome metabólica. Entretanto,esses resultados reforçam a importância do monitoramento clínico para prevenir os impactos da hipovitaminose D nos indivíduos com síndrome metabólica e o desenvolvimento de novos estudos para avaliar a relação entre status de 25(OH)D e risco cardiovascular.

Introduction: Metabolic syndrome is a set of metabolic disorders that are considered cardiovascular risk factors. It is estimated that individuals with metabolic syndrome are three times more likely to develop cardiovascular disease. Inadequate vitamin D status has shown multiple pathophysiological mechanisms that suggest an involvement in the development of cardiovascular disease. Objective: To evaluate the association between vitamin D status and the risk of cardiovascular disease in individuals with metabolic syndrome. Methods: This is a cross-sectional study carried out with 161 adult individuals diagnosed with metabolic syndrome. Anthropometric measurements, blood pressure, and biochemical analyzes were performed, including serum 25(OH)D status. The established criterion for classifying 25(OH)D status was deficient < 20 ng/mL; insufficient ≤ 29 ng/mL and sufficient ≥ 30 ng/mL. Furthermore, the absolute risk of developing cardiovascular disease was assessed using the Framingham Risk Score. Results: The mean 25(OH)D concentration was 29.7 (21-34) ng/mL, indicating insufficient 25(OH)D status in the population. There was no association between vitamin D status and cardiovascular risk in subjects with metabolic syndrome (p > 0.05). Conclusion: There was no association between inadequate 25(OH)D status and increased cardiovascular risk in individuals with metabolic syndrome. However, these results reinforce the importance of clinical monitoring to prevent the impacts of hypovitaminosis D in individuals with metabolic syndrome and the development of new studies to assess the relationship between 25(OH)D status and cardiovascular risk.

Effects of vitamin D supplementation on fasting glucose, dyslipidemia, blood pressure, and abdominal obesity among patients with metabolic syndrome: a protocol for systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Vitamin D deficiency can play a role in extraskeletal functions that are involved with a set of risk factors associated with metabolic syndrome (MetS). The purpose of this review is to investigate the impact of vitamin D supplementation on fasting glucose, dyslipidemia, blood pressure, and abdominal obesity among patients with MetS. METHODS: EMBASE, Medline, Web of Science, Lilacs, the Cochrane Central Register of Controlled Trials, clinicaltrials.gov databases, and grey literature will be systematically searched for randomized controlled trials (RCTs) of vitamin D supplementation compared with placebo, through December 2020. We will include in the study patients with MetS diagnosed by the criteria set forth by the National Cholesterol Education Program Adult Treatment Panel III or the International Diabetes Federation. The effect of oral vitamin D supplementation on lipid profile improvement (triglycerides, high-density lipoprotein cholesterol-HDL-C) is this review's primary outcome. The systematic review will be performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The study screening, data extraction, and quality assessment will be fulfilled by two independent reviewers according to the Cochrane Risk of Bias tool (RoB 2.0). The results of the systematic review will be provided according to the type of intervention, characteristics of the target population, the methods of measurement of vitamin D, the calculated vitamin D concentrations, types of biological samples, and types of outcomes. Meta-analyses will be conducted where appropriate. The Cochran's Q test and the I2-heterogeneity test will be used to assess the presence of heterogeneity and whether the fixed or the random-effects model would be appropriate for combining study results using the inverse variance method or the DerSimonian-Lair method, respectively. Publication bias will be evaluated using funnel plots and Egger's and Begg's tests. The strength of the evidence will be assessed according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE). DISCUSSION: This systematic review will assess the effects of vitamin D supplementation on fasting glucose and triglyceride levels, waist circumference and mean blood pressure, and HDL-C among individuals with MetS. These findings may assist with decision-making within a clinical setting. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration number CRD42019123212.

Predictors of 25-hydroxyvitamin D status among individuals with metabolic syndrome: a cross-sectional study.

BACKGROUND: The risk of metabolic syndrome can be influenced by inadequate vitamin D levels, and exposure to sunlight is the main external source of vitamin D. The present study assessed the influence of environmental, biological, and nutritional factors in relation to seasonal 25-hydroxyvitamin D (25OHD) concentration in individuals with metabolic syndrome. METHODS: This cross-sectional study enrolled 180 individuals with metabolic syndrome aged between 18 and 80 years. The 25OHD concentration was considered the dependent variable; independent variables included age, sex, skin color, use of sunscreen, skin type, sun exposure score, ultraviolet radiation index, geographic location, season, body mass index, waist:hip ratio, waist circumference, parathyroid hormone level, total serum calcium level, and calcium and vitamin D intake. RESULTS: The average vitamin D in individuals evaluated in summer 32 ± 10 ng/mL was greater than in the winter 26 ± 8 ng/mL (p < 0.017). HDL-cholesterol was the only component of the MetS that differed significantly between the seasons (p < 0.001), showing higher concentrations in autumn 45 ± 8 mg/dL than in summer 35 ± 8 mg/dL. In the multiple regression model, gender, WHR, sun exposure score, and winter vs. summer explained 10% of the variation in 25OHD concentration (p = 0.004). CONCLUSIONS: Sex, waist:hip ratio, sun exposure, and summer season were predictors of 25OHD status among individuals with metabolic syndrome. HDL-cholesterol was the only component of metabolic syndrome that differed significantly between the seasons.

Inadequacies in the habitual nutrient intakes of patients with metabolic syndrome: a cross-sectional study.

BACKGROUND: Dietary factors are important environmental factors associated with the prevalence of metabolic syndrome (MS). The objective of this study was to assess the habitual nutrient intakes of patients with MS. METHODS: A cross-sectional study included 103 patients (82 % women) with MS seen at the endocrinology outpatient clinic of Hospital Universitario Onofre Lopes. Habitual nutrient intake data were collected at two 24-h dietary recalls. Macronutrient intake adequacies were classified according to the I Brazilian guidelines for the diagnosis and treatment of metabolic syndrome. The prevalence of inadequate micronutrient intake was estimated using the estimated average requirements (EAR) cut-point method after adjusting for intra- and interpersonal variances and energy. RESULTS: The mean energy intake of the included patients was 1523.0 ± 592.2 kcal/d, higher in men (1884.0 vs. 1441.5 kcal/d in women; p = 0.003). The recommended percentage protein intake was exceeded in both women and men (18 % in women and 19 % in men). Although men consumed more fiber (18.8 vs. 13.3 g/d in women; p = 0.011), their intake was still inadequate. Women consumed more fat (47.6 vs. 41.3 g/d in men; p = 0.007). The prevalence of inadequate vitamin D and calcium intakes exceeded 80 % in both men and women and across all age groups. The same was observed for magnesium in men and women aged more than 30 years. The prevalence of inadequate vitamin E, riboflavin, and zinc intakes in men ranged from 50 to 75 %. The prevalence of inadequate vitamin A, vitamin C, thiamin, vitamin B6, copper, and selenium intakes in men and women was less than 50 %. CONCLUSIONS: Patients with MS had high protein intake, low fiber intake, and high a prevalence of inadequate vitamin D, magnesium, and calcium intakes.