International Journal of Endocrinology and Metabolism最新文献

Background: Heart failure is a pathophysiologic state in which the cardiac output is not able to supply the body with enough oxygen and nutrients. The prevalence of heart failure has increased dramatically over the last decades. Vitamin D levels in patients with chronic heart failure are lower than healthy controls, and vitamin D deficiency has a direct relationship with mortality.

Objectives: This study aimed to evaluate the effect of vitamin D on the improvement of left ventricular ejection fraction in patients with systolic heart failure.

Methods: In this case-control clinical trial, 142 patients with chronic systolic heart failure were identified. Based on the inclusion and exclusion criteria, 114 patients were enrolled in the study and randomly divided into two groups. One group (n = 58) received 50,000 units of vitamin D capsules weekly for eight weeks, and the patients in the other group (n = 56) received a placebo. After excluding 15 patients from the placebo group and 17 patients from the intervention group during the study, according to the exclusion criteria, 41 patients were evaluated in both groups for ejection fraction changes after two months.

Results: According to the results of this research, there were no statistically significant differences in the baseline parameters between the two studied groups. The intervention group consisted of 18 female and 23 male patients with a mean age of 61.68 ± 19.8 years. Moreover, the placebo group included 21 female and 20 male patients with a mean age of 62.12 ± 18.2 years. After a 2-month follow-up, the intervention group showed statistically significant changes in ejection fraction, end-diastolic volume, and heart failure class compared to the placebo group. Also, the serum level of albumin and vitamin D in the intervention group was significantly higher than the placebo group.

Conclusions: The results of this study show that vitamin D treatment can improve the ejection fraction and functional ability of patients with vitamin D deficiency. If more comprehensive studies support this hypothesis, vitamin D deficiency assessment and correction in patients with chronic heart failure may be recommended.

Background: Evening chronotype is usually associated with insomnia and short sleep duration.

Objectives: To investigate the independent association of chronotype with diabetes control.

Methods: In this cross-sectional study, 140 patients with type 2 diabetes were studied. The insomnia score was examined by a 7-item questionnaire. Also, chronotype was assessed by a 19-item questionnaire, and using the questionnaire, the patients were divided into three groups of morning, intermediate, and evening. This questionnaire has been developed for evaluating the preference for performing mental and physical activities at a special time of day. The Multivariate hierarchical analysis was applied for investigating the independent association of chronotype and glycated hemoglobin (HbA1c).

Results: The fasting blood glucose and HbA1c levels were significantly different across all the three chronotype groups such that it had the highest value in the evening group and the lowest value in the morning group (FBS = 164.5 ± 34.1 mg/dL and HbA1c = 8.7% ± 1.7, in the evening group, and FBS = 132.7 ± 23.1 mg/dL and HbA1c = 6.9% ± 0.4 in the morning group, P < 0.001). The morning group had longer sleep duration and less insomnia than other groups. Results of the hierarchical regression analysis showed that the chronotype explained 28.4% of the variance of HbA1c. Results of the final model demonstrated that the chronotype had a relationship with HbA1c, independent of body mass index (BMI), time of going to bed, and insomnia score.

Conclusions: Evening chronotype is associated with poorer control of diabetes, independent of BMI and sleep variables.

Context: Considering the increasing trend in the incidence of type 1 diabetes mellitus (T1DM), the identification of its environmental determinants, especially those related to the prenatal and lactation period, might ultimately result in primary prevention of the disease. We aimed to review the evidence of the association between mothers' dietary components during pregnancy and/or lactation with T1DM.

Evidence acquisition: An electronic and comprehensive literature search was performed until August 2019 in the international databases, including Web of Science (ISI), PubMed, and Scopus, using the following keywords: type 1 diabetes mellitus, autoimmunity, mother, maternal, diet and lactation in different combinations. Papers related to the objectives of the study were selected.

Results: Based on our review, the maternal consumption of meat, especially processed meat, was associated with increased risk of T1DM, whereas the maternal use of vegetables, potato, low-fat margarine, and berries showed protective effects against the development of T1DM in offspring. There was no significant association between the use of multivitamins and mineral supplements with T1DM, according to the available data. The results of the reviewed studies regarding the association between the maternal use of vitamin D, fatty acids, and coffee during pregnancy with T1DM were not consistent and conclusive.

Conclusions: Findings of this review indicate that the maternal consumption of some foods is associated with increased or decreased risk of T1DM. However, for some foods or dietary components, including coffee, vitamin D, and fatty acids, the results are not conclusive. We conclude that although maternal diet could influence the development of insulin autoantibodies (IA) and T1DM in offspring, there is no sufficient evidence for most nutrients, and available data are controversial, which should be dealt with in future cohort or interventional studies.

Context: Vitamin D (VD) has been found to play a key role in nonalcoholic fatty liver disease (NAFLD). This meta-analysis explored the effects of VD supplementation in patients with NAFLD.

Methods: The PubMed, EMBASE, and the Cochrane Library databases were searched to find randomized control trials (RCTs) that measured the changes between the VD supplement group and the control group until May 2019. Standard mean difference (SMD) with 95% confidence intervals (CI) was calculated when data units were different, otherwise weighted mean difference (WMD) and 95% CI was calculated. Heterogeneity was assessed using the I2 statistic.

Results: Eight RCTs with 624 individuals were extracted. The main indicators, including serum alanine aminotransferase (WMD = -0.052; 95% CI: -3.740, 3.636; P = 0.978) and aspartate aminotransferase concentrations (WMD = -0.479; 95% CI: -2.791, 1.833; P = 0.685) were not significantly different between the intervention and placebo groups. In addition, no significant intergroup difference was observed in the following secondary indicators: fasting blood glucose (WMD = 0.466; 95% CI: -5.313, -10.879; P = 0.061), homeostasis model assessment (WMD = 0.380, 95% CI: -0.162, 0.923; P = 0.169), serum insulin concentration (WMD = 0.760; 95% CI: -0.532, 2.052; P = 0.249), high-density lipoprotein (WMD = -0.012; 95% CI: -0.188, 0.164; P = 0.891), and low-density lipoprotein (WMD = -0.115; 95% CI: -3.849, -3.620; P = 0.952).

Conclusions: The results indicate that VD supplementation does not improve liver enzymes, insulin resistance, glucose metabolism parameters, and lipid levels in patients with NAFLD.

Background: The glycemic index (GI) values of staple foods are not available in a standardized method in Iran.

Objectives: The aim of this study was to measure the GI values of the major carbohydrate sources in a typical Iranian diet.

Methods: Using the international standard method, the GI values were determined for four wheat flatbreads, barley and rye bread, white and brown rice, as well as white and brown rice mixed with lentils. Twelve healthy adults were given 50 g anhydrous glucose three times (as the reference carbohydrate) and the test foods once each throughout the study. Using finger-prick blood samples, capillary blood glucose was measured using a reliable glucometer. The GI was calculated using the trapezoidal method.

Results: The GI values of the following types of bread were: Barley 66, Lavash 72, Taftoon 79, Sangak 82, rye 84, and Barbari 99. The GI values for brown and white rice were 65 and 71, respectively. The mixture of brown rice with lentils had a GI value of 55, and the mixture of white rice with lentils had a GI of 79.

Conclusions: The most common types of bread and white rice consumed in Iran have high GI values. There is potential to reduce the overall GI values in the Iranian diet by encouraging the consumption of barley bread and brown rice.