COVID-19 and Vitamin D (Co-VIVID Study): a systematic review and meta-analysis of randomized controlled trials

BackgroundVitamin D levels have been reported to be associated with COVID-19 susceptibility, severity and mortality events.. We performed a meta-analysis of randomized controlled trials (RCTs) to evaluate the use of vitamin D intervention on COVID-19 outcomes. MethodsLiterature search was conducted using PubMed, Cochrane library, and ClinicalTrials.gov databases (latest search on August 5, 2021). We included RCTs reporting the use of vitamin D intervention to control/placebo group in COVID-19. Two independent researchers did literature search, abstracted data, and the risk of bias assessment. ResultsA total of 6 RCTs with 551 COVID-19 patients were included. The overall collective evidence pooling all the outcomes across all RCTs indicated the beneficial use of vitamin D intervention in COVID-19 (relative risk, RR = 0.60, 95% CI 0.40 to 0.92, Z=2.33, p=0.02, I2 = 48%). However, no statistical significance was observed for individual outcomes of ICU care (RR = 0.11, 95% CI 0.15 to 1.30, Z=1.48, p=0.14, I2 = 66%) and mortality (RR = 0.78, 95% CI 0.25 to 2.40, Z=0.66, p=0.02, I2 = 33%), though decreased rates were noted. The rates of RT-CR positivity was significantly decreased in the intervention group as compared to the non-vitamin D groups (RR = 0.46, 95% CI 0.24 to 0.89, Z=2.31, p=0.02, I2 = 0%). ConclusionCOVID-19 patients supplemented with vitamin D are more likely to demonstrate fewer rates of ICU admission, mortality events and RT-PCR positivity. However, no statistical significance has been achieved for individual outcomes of ICU and deaths. More RCTs and completion of ongoing trials largely needed to precisely establish the association between vitamin D use and COVID-19.

A diagnostic test accuracy meta-analysis of maternal serum ischemia-modified albumin for detection of preeclampsia.

BACKGROUND/AIMS: Ischemia-modified albumin (IMA) has been widely accepted as a serological biomarker. IMA has been proposed as a simple and novel marker of oxidative stress in preeclampsia (PE). This systematic review and diagnostic test accuracy meta-analysis aims to evaluate the diagnostic accuracy of this novel serological biomarker, IMA to detect PE. METHODS: A systematic search of major databases was performed to identify all published diagnostic accuracy studies on IMA. Risk of bias and applicability concerns were assessed for included studies. Summary estimates; the pooled sensitivity, specificity, and the diagnostic odds ratio (DOR) of IMA for the diagnosis of PE were computed using random-effects models. The overall test performance was summarized using summary receiver operating characteristic (SROC) curve analysis. RESULTS: Six articles were included in this meta-analysis. The overall estimates of IMA in detecting PE were pooled sensitivity; 0.80 (95%CI 0.73-0.86), pooled specificity; 0.76 (95%CI 0.70-0.81), DOR; 14.32 (95%CI 5.06-40.57), and area under curve (AUC); 0.860. There was no between-study heterogeneity due to threshold effect. CONCLUSIONS: This meta-analysis showed IMA could be useful as a biomarker for PE with good accuracy (AUC = 0.860). However, further research is needed for re-evaluation and clinical validation of fairly promising results of this meta-analysis.

Elevated levels of the circulatory ischemia-modified albumin in patients with polycystic ovary syndrome: a meta-analysis.

Oxidative stress (OS) has been reported to be associated with the pathogenesis of polycystic ovary syndrome (PCOS). Ischemia-modified albumin (IMA) levels in the circulation have been recently studied as a novel marker of OS. The studies in the literature on IMA levels in PCOS are inconsistent. This meta-analysis was conducted to compare circulatory IMA levels between PCOS patients and non-PCOS controls. Relevant studies were retrieved by online database and manual searching. The standardized mean differences (SMDs) with 95% confidence intervals (CIs) were obtained by a random-effects meta-analysis. The funnel plot analysis with Begg's and Egger's tests was used for publication bias. A total of nine studies were included in this meta-analysis. The results indicated that the serum IMA levels were significantly elevated in PCOS patients as compared to non-PCOS controls (SMD = 0.49, 95% CI = 0.23-0.75, Z = 3.75, p = .0002). A one-study leave-out sensitivity analysis indicated that no single study had a significant influence on the overall outcome, suggesting the good validity and stability of these meta-analytic results. There was no evidence of publication bias as evidenced by the Egger (p = .28) and Begg's tests (p = .21). The present meta-analysis suggests that IMA might be considered as a reliable and novel marker reflecting increased OS in PCOS.

Maternal serum and fetal cord-blood ischemia-modified albumin concentrations in normal pregnancy and preeclampsia: a systematic review and meta-analysis.

BACKGROUND/AIMS: A meta-analysis of maternal serum ischemia-modified albumin (IMA) and fetal cord-blood IMA concentrations in normal pregnancy (NP) compared to non-pregnant healthy controls (HC) and in preeclampsia (PE) compared with normal pregnant controls were studied. METHODS: All major databases were searched for eligible studies. We included eight studies comparing serum IMA between NP and HC, 14 studies comparing serum IMA between PE and NP and five studies comparing cord-blood IMA between PE and NP groups. Meta-analyses on these included studies were performed using Review Manager 5.3. Pooled-overall effect size as standardized mean difference (SMD), publication bias, subgroup, and sensitivity analysis data were generated. RESULTS: Random-effects meta-analysis indicated a significant increase in serum IMA in the NP group (SMD = 0.98, p = .01) and the PE group (SMD = 0.94, p < .0001) as compared with HC and NP groups, respectively. And, the cord-blood IMA has been found to be significantly increased in PE (SMD = 6.51, p < .0001) compared with the NP group. CONCLUSIONS: This meta-analysis, the first of its kind showed that the increased serum IMA concentrations were indicative of increased oxidative stress in NP and PE. Measurement of maternal serum IMA and fetal cord-blood IMA concentrations were useful as simple, novel, and inexpensive markers of oxidative stress (OS) status in PE patients. Future large-scale studies are needed to explore IMA in relationship to the disease severity in PE.

SIGNIFICANCE OF ISCHEMIA-MODIFIED ALBUMIN AS A SIMPLE MEASURE OF OXIDATIVE STRESS AND ITS DISCRIMINATORY ABILITY IN DIABETIC RETINOPATHY: Literature Review and Meta-Analysis.

PURPOSE: Oxidative stress (OXS) plays critical role in the development of diabetic retinopathy (DRP). Increased concentrations of serum ischemia-modified albumin (IMA) have been demonstrated as a novel and inexpensive measure of oxidative stress. Although few pilot studies have reported increased IMA in DRP, the available literature is limited to comprehensively describe the potential significance of IMA in predicting DRP. METHODS: The authors performed a meta-analysis to investigate IMA in DRP compared with control and diabetes mellitus subjects. The authors also performed a meta-analysis of area under curve for IMA. PubMed (Medline), Embase, Scopus, Web of Science, Science Direct, Springer Link, and Google Scholar databases were searched for relevant studies in serum IMA in DRP. The authors obtained five observational studies. Meta-analysis was performed using Review Manager 5.3 and MEDCALC 15.8 software to present the pooled-overall effect size as standardized mean difference and overall area under curve value of IMA. RESULTS: Random-effects meta-analysis indicated a significant increase in serum IMA in patients with DRP compared with control (standardized mean difference = 2.48, P < 0.0001) and diabetes mellitus groups (standardized mean difference = 1.43, P < 0.0001). Our results also show that IMA can significantly predict the development of DRP (area under curve = 0.86, P < 0.001). CONCLUSION: Serum IMA may be useful as a simple marker in monitoring of oxidative stress status in DRP and showed significant discriminatory ability in DRP. Future comparative studies in large are needed to further investigate IMA in different types of DRP; proliferative and nonproliferative.