The role of vitamin D in outcomes of critical care in COVID-19 patients: Evidence from an umbrella meta-analysis of interventional and observational studies.

OBJECTIVES: Several meta-analyses have suggested the beneficial effect of vitamin D on patients infected with SARS-CoV-2. This umbrella meta-analysis aims to evaluate influence of vitamin D supplementation on clinical outcomes and the mortality rate of COVID-19 patients. DESIGN: Present study was designed as an umbrella meta-analysis. The following international databases were systematically searched till March 2023: Web of Science, PubMed, Scopus, and Embase. SETTINGS: Random-effects model was employed to perform meta-analysis. Using AMSTAR critical evaluation tools, the methodological quality of the included meta-analyses was evaluated. PARTICIPANTS: Adult patients suffering from COVID-19 were studied. RESULTS: Overall, 13 meta-analyses summarizing data from 4 RCTs and 9 observational studies were identified in this umbrella review. Our findings revealed that vitamin D supplementation and status significantly reduced mortality of COVID-19 [Interventional studies: (ES= 0.42; 95% CI: 0.10, 0.75, p <0.001; I2 = 20.4%, p=0.285) and observational studies (ES= 1.99; 95% CI: 1.37, 2.62, p <0.001; I2 = 00.0%, p=0.944). Also, vitamin D deficiency increased risk of infection and disease severity among patients. CONCLUSION: Overall, vitamin D status is a critical factor influencing the mortality rate, disease severity, admission to ICU and being detached from mechanical ventilation. It is vital to monitor the vitamin D status in all patients with critical conditions including COVID patients.

The early life growth of head circumference, weight, and height in infants with autism spectrum disorders: a systematic review.

BACKGROUNDS: The Autism spectrum disorder (ASD) prevalence has increased significantly over the past two decades. This review summarizes the current knowledge of the association between the early life growth of head circumference (HC), weight, and height with ASD in infants. METHODS: PubMed, Scopus, Science Direct, and Google Scholar databases were searched up to November 2021 using relevant keywords. All original articles are written in English evaluating the early life growth of HC, weight, and height in infants with ASD were eligible for the present review. RESULTS: Totally, 23 articles involving 4959 infants were included in this review. Of 13 studies that evaluated HC of infants at birth, 10 studies (83.33%) showed that the HC at the birth of autistic children was similar to that of the average found in the control group. Among 21 studies that evaluated the HC and weight status in infants, 19 studies (90.47%) showed that autistic children had larger HC and weight than the control group or abnormal acceleration of head growth during infancy. Height growth of infants was investigated in 13 studies, of which 10 cases (76.92%) reported that infants with ASD were significantly longer than control groups. Most of he included studies had a good quality. CONCLUSIONS: The findings suggest that in infants with ASD, without the contribution of birth growth factors and sex of the child, the growth of HC, weight, and height probably was faster than in infants with normal development, in early life. Therefore, these measurements might be useful as initial predictive biomarkers for the risk of developing ASD.

The Impact of Vitamin D Supplementation on Improving Blood Pressure: Evidence Obtained From an Umbrella Meta-analysis.

PURPOSE: The results of meta-analyses regarding the effect of vitamin D on blood pressure are conflicting. The present umbrella meta-analysis was conducted to provide definite and conclusive results. METHODS: Systematically, Scopus, EMBASE, PubMed, and Web of Science databases and Google Scholar were searched for relevant literature published up to July 2022. All meta-analyses of clinical trials addressing the effect of vitamin D on blood pressure were included. Random effects analysis was performed to obtain the overall effect size based on the standardized mean differences (SMDs) and weighted mean differences (WMDs) separately. The quality of included meta-analyses was assessed by using the Measurement Tool for Assessing Multiple Systematic Reviews 2 questionnaire. FINDINGS: Overall, 21 meta-analyses were enrolled in the umbrella review. The results indicated that systolic blood pressure was significantly reduced after the intervention based on WMD effect size analysis (ESWMD = -0.69 mm Hg; 95% CI, -1.35 to -0.04 [P < 0.038]; I2 = 46.7%, P = 0.021); however, no considerable impact was observed based on analysis of SMD effect sizes (ESSMD = -0.05 mm Hg; 95% CI, -0.24 to 0.14; P = 0.615). Also, vitamin D supplementation indicated a significant improvement in diastolic blood pressure based on WMD effect sizes (ESWMD = -0.66 mm Hg; 95% CI, -1.05 to -0.27 [P < 0.001]; I2 = 56.4%, P = 0.004) but not SMD analysis (ESSMD = -0.04 mm Hg; 95% CI, -0.13 to 0.04 [P = 0.328]; I2 = 53.4%, P = 0.057). IMPLICATIONS: Based on obtained evidence, vitamin D could be considered an efficient adjuvant for improving blood pressure.

Inositol supplementation and body mass index: A systematic review and meta-analysis of randomized clinical trials.

Background: Inositol is a sugar-alcohol and recognized as a key component of cell membrane phospholipids. It has crucial role in the cell signaling pathways and contribute to improving glycemic responses. Although some earlier studies have revealed the effect of inositol mediating glucose uptake by improving insulin sensitivity, the benefit of inositol supplementation in patients with overweight and obesity is not completely understood. This study aimed to assess the impact of inositol supplementation on body mass index (BMI) through a systematic review and meta-analysis of controlled clinical trials. Methods: A systematic search was performed to August 2021 in the following databases: PubMed-Medline, Embase, Web of Science and Scopus. Fifteen controlled clinical trials investigating the effect of inositol on adult's BMI were finally included in the study. A random-effects model was employed to estimate the effect size. Subgroup analysis was performed by dose, duration, age, type of inositol. Meta-regression was used to investigate presence of any linear relationship. Begg's and Egger's tests were carried out to detect small study effect. Results: The results of pooled analysis showed that inositol supplementation significantly decreased BMI scores (WMD = -0.41 kg/m2; 95% CI: -0.78, -0.04; p = 0.028). Subgroup analysis was performed to identify the source of heterogeneity among studies (I 2 = 73.9%, p < 0.001), demonstrating supplementation duration, baseline BMI, mean age of participants, type of inositol and dosage were potential sources of heterogeneity. The effect of intervention was more clinically significant in participants with polycystic ovary syndrome (PCOS) and overweight/obesity. Inositol in the form of myo-inositol (MI) had stronger effect on BMI reduction. Conclusion: The meta-analysis suggests that oral inositol supplementation has positive effect on BMI reduction. Inositol supplementation could be considered as an adjunct treatment to improve body mass index.

Responsible enzymes for metabolizing vitamin D in patients with acute leukemia and the relationship with treatment outcomes: a case-control study.

Anti-cancer properties of vitamin D have been reported in studies. The aim of this study was to evaluate the expression of some key enzymes involved in vitamin D metabolism and the serum levels of related proteins. Fifty-four patients with acute myeloid leukemia (AML) and 55 eligible individuals were studied as the control group. The expression of VDR, CYP27B1, and CYP24A1 genes was measured. Serum levels of related proteins were quantified. The association between the studied variables and treatment outcomes: duration of fever and neutropenia, length of hospital stay, achievement of complete remission and overall survival has been investigated. Expression of CYP24A1 gene and serum levels of CYP27B1 and CYP24A1 proteins were significantly higher in the patient group. CYP24A1 gene expression, its blood concentrations and serum levels of CYP27B1 were significantly higher in the AML group. Vitamin D status and key enzymes did not show a strong change in AML patients neither did associate with treatment outcomes except CYP24A1.

Effect of L-Carnitine Supplementation on Inflammatory Markers and Serum Glucose in Hemodialysis Children: A Randomized, Placebo-Controlled Clinical Trial.

OBJECTIVES: Chronic inflammation is present in a high proportion of the chronic kidney disease (CKD) population, which can increase the risk of cardiovascular disease. Moreover, it is known as the leading cause of death in these patients. In addition, change in glucose metabolism is another common problem among CKD population. In this regard, it was found that insulin resistance and inflammation can perpetuate each other and simultaneously cause atherosclerosis. Because some studies have previously shown the positive effects of L-carnitine on reducing inflammation and controlling blood sugar, in the present study, we examined the effects of L-carnitine supplementation on serum inflammatory markers, fasting blood sugar (FBS), free carnitine (FC), albumin levels, and quality of life score among children on hemodialysis. METHOD: Twenty-four children on hemodialysis (aged between 6 and 18 years) were enrolled in this randomized clinical trial study. Thereafter, 12 patients received 50 mg/kg of L-carnitine and 12 patients received placebo for a 10-week period. Afterward, we determined serum FC, interleukin-6 (IL-6), high-sensitivity C-reactive protein, FBS, and albumin and Pediatrics Quality of Life scores once at the baseline and once after performing intervention for 10 weeks. Moreover, the one-way repeated measures analysis was used to evaluate the effects of L-carnitine supplementation. RESULTS: Although oral L-carnitine supplementation led to the decreased high-sensitivity C-reactive protein, this change was not significant compared with the placebo. Also, L-carnitine supplementation has significantly reduced serum levels of IL-6 and FBS, which has also raised serum FC and Pediatrics Quality of Life scores compared with the placebo. Notably, no significant change was observed in serum albumin levels. CONCLUSION: Given the significant reductions in IL-6 and FBS levels, L-carnitine supplementation appeared to have some positive effects on the inflammation, blood glucose control, and prevention of cardiovascular events in these patients, as well as the improvement of quality of life. In this regard, L-carnitine therapy with a longer duration is recommended to obtain more effective results.

Effect of L-carnitine supplementation on lipid profile and apolipoproteins in children on hemodialysis: a randomized placebo-controlled clinical trial.

BACKGROUND: Cardiovascular disease (CVD) is the leading cause of death in children with chronic kidney disease (CKD) and accounts for 40% of all deaths among pediatric patients with stage 5 chronic kidney disease (CKD 5). Dyslipidemia is common in children with CKD and is considered one of the major causes of CVD in these patients. As carnitine plays a key role in lipid metabolism and because plasma levels are reduced in hemodialysis patients, the aim of this study was to determine the effects of L-carnitine supplementation on serum lipid profiles, apolipoproteins, and free carnitine (FC) levels. METHODS: A total of 30 children on hemodialysis (6-18 years) were enrolled and 24 completed the study. Twelve patients received 50 mg/kg/day L-carnitine, while the other 12 patients received placebo for 10 weeks. Serum FC, total cholesterol (TC), LDL-C, HDL-C, TG, Apolipoprotein B (ApoB), and Apolipoprotein A1 (ApoA1) were determined at the baseline and after the intervention. One-way repeated measures analysis was used to evaluate the effects of L-carnitine supplementation. RESULTS: Oral L-carnitine supplementation led to decreased ApoB levels and ApoB/ApoA1 ratio, but these changes were not significant compared to placebo. Meanwhile, L-carnitine supplementation significantly reduced serum LDL-C and TC and increased serum FC compared to placebo. No significant changes were observed in serum TG and HDL-C levels. CONCLUSION: Given the significant reduction in LDL-C and TC levels, L-carnitine supplementation had positive effects on improving hyperlipidemia in children receiving hemodialysis. For more decisive results, studies with longer duration of L-carnitine therapy on children receiving hemodialysis with significant dyslipidemia are recommended. TRIAL REGISTRATION: We registered the present trial in the Iranian Registry of Clinical Trials website (available at: http://www.irct.ir , identifier: IRCT20170202032367N2).