Proinflammatory Cytokine Levels in Sepsis and in Health and TNFα Association with Sepsis Mortality and patient characteristics: a Systematic Review and Meta-analysis

Background: Sepsis is a global health problem associated with significant morbidity and mortality. Detrimental sepsis effects are attributed to a "cytokine storm." However, anti-cytokine therapies have failed to lower sepsis mortality. We aim to characterize levels of key cytokines in sepsis patients and healthy controls and relate TNFα levels to patient characteristics and outcomes. Methods: We performed a systematic review and meta-analysis. Medline, Embase, Cochrane Library, and Web of Science Core Collection databases were searched from 1985 to May 2020 for studies in English. We included randomized controlled trials (RCTs), controlled trials, cohort studies, case series, and cross-sectional studies that reported mean levels of cytokines in the circulation thought to be relevant for sepsis pathogenesis. We also evaluated concentrations of these cytokines in healthy persons. Quality in Prognosis Studies tool was used to assess the methodological quality of included studies. We extracted summary data from published reports. Data analyses were performed using a random-effects model to estimate pooled odds ratios (OR) with 95% confidence intervals for cytokine levels and mortality. This systematic review is registered in PROSPERO (CRD42020179800). Findings: We identified 3654 records, and 104 studies were included with a total of 3250 participants. The pooled estimated mean TNFα concentration in sepsis patients was 58.4 pg/ml (95% Confidence Interval or CI 39.8-85.8 pg/ml) and 5.5 pg/ml (95% CI 3.8-8.0 pg/ml) in healthy controls. Pooled estimate means for IL-1β and IFNγ in sepsis patients were 21.8 pg/ml and 63.3 pg/ml, respectively. Elevated TNFα concentrations associated with increased 28-day sepsis mortality (p=0.001). In subgroup analyses, TNFα levels did not relate to sepsis source, sepsis severity, or sequential organ failure assessment (SOFA) score. Interpretation: TNFα concentration in sepsis is increased approximately 10-fold compared to healthy persons, and TNFα associated with sepsis mortality but not with sepsis severity. The concept that elevated cytokines cause sepsis should be revisited in the context of these data.

Download Full-text

1003. Cytokine Levels in Sepsis and TNFα Association with Mortality but not Sepsis Severity or Infection Source: a Systematic Review and Meta-analysis

Open Forum Infectious Diseases ◽

10.1093/ofid/ofab466.1197 ◽

2021 ◽

Vol 8 (Supplement_1) ◽

pp. S592-S592

Author(s):

Amal Gharamti ◽

Omar Samara ◽

Anthony Monzon ◽

Lilian Vargas Barahona ◽

Sias Scherger ◽

...

Keyword(s):

Systematic Review ◽

Sofa Score ◽

Meta Analysis ◽

Purpura Fulminans ◽

Cochrane Library ◽

Mortality Data ◽

Sepsis Severity ◽

Sepsis Mortality ◽

Human Sepsis ◽

Cytokine Levels

Abstract Background Sepsis is a global health problem associated with significant morbidity and mortality and is attributed to a “cytokine storm.”. However, anti-cytokine therapies have failed to lower sepsis mortality in clinical trials. Linking cytokine excess to sepsis pathogenesis requires quantification of cytokine levels in sepsis. This systematic review and meta-analysis characterizes levels of key cytokines in the circulation of sepsis patients and relates TNFα levels to mortality and patient characteristics. Methods Medline, Embase, Cochrane Library, and Web of Science Core Collection databases were searched from 1946 to May 2020 for studies in English disclosing cytokine levels in sepsis. Keywords included sepsis, septic shock, purpura fulminans, and tumor necrosis factor (TNF)α. We related cytokine amounts to 28-day mortality. Data analyses were performed using a random-effects model to estimate pooled odds ratios (OR) and 95% confidence intervals (CI). This systematic review is registered in PROSPERO under number CRD42020179800. Results A total of 3656 records were identified. After exclusions, 103 studies were included. Among these studies, 72 disclosed TNFα levels, 25 showed interleukin (IL)-1β levels, and 6 presented interferon (IFN)γ levels. The pooled estimate mean TNFα concentration in sepsis patients was 58.4 pg/ml (95% CI, 39.8-85.8 pg.ml; I2 = 99.4%). Pooled estimate means for IL-1α and IFNγ in sepsis patients were 21.8 pg/ml (95% CI, 12.6-37.8 pg.ml; I2 =99.8%) and 63.3 pg/ml (95% CI, 19.4-206.6 pg/ml; I2 = 99.7%), respectively. Elevated TNFα concentrations were associated with increased 28-day mortality (P=0.001). In a subgroup analysis, TNFα levels did not relate to sepsis source, sepsis severity, or sequential organ failure assessment (SOFA) score (figure 1). In a metaregression, TNFα associated with age, percentage of females and mortality at 28 days. Figure 1: A: TNFa levels according to sepsis source. B: TNFa levels according to measurement technique. C: TNFa levels according to presence or absence of cardiovascular disease. D: TNFa levels according to presence or absence of malignancy. E: TNFa levels according to sepsis severity. F: TNFa levels in fungal compared to other causes of sepsis (Yes=fungal sepsis; No= Other types of sepsis). G: TNFa levels according to SOFA score. H: TNFa levels and mortality at 28 days. Conclusion We presented levels of TNFα, IL-1β, and IFNγ in human sepsis and showed that TNFα elevations are associated with sepsis mortality. TNFα concentrations did not correlate with sepsis severity. We believe the concept that elevated cytokines cause sepsis should be revisited in the context of these data. Disclosures All Authors: No reported disclosures

Download Full-text

Adjuvant Transarterial Chemoembolization Following Curative-Intent Hepatectomy Versus Hepatectomy Alone for Hepatocellular Carcinoma: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Cancers ◽

10.3390/cancers13122984 ◽

2021 ◽

Vol 13 (12) ◽

pp. 2984

Author(s):

Stepan M. Esagian ◽

Christos D. Kakos ◽

Emmanouil Giorgakis ◽

Lyle Burdine ◽

J. Camilo Barreto ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Systematic Review ◽

Randomized Controlled Trials ◽

Transarterial Chemoembolization ◽

Meta Analysis ◽

Risk Of Bias ◽

Cochrane Library ◽

Controlled Trials ◽

Curative Intent ◽

Randomized Controlled

The role of adjuvant transarterial chemoembolization (TACE) for patients with resectable hepatocellular carcinoma (HCC) undergoing hepatectomy is currently unclear. We performed a systematic review of the literature using the MEDLINE, Embase, and Cochrane Library databases. Random-effects meta-analysis was carried out to compare the overall survival (OS) and recurrence-free survival (RFS) of patients with resectable HCC undergoing hepatectomy followed by adjuvant TACE vs. hepatectomy alone in randomized controlled trials (RCTs). The risk of bias was assessed using the Risk of Bias 2.0 tool. Meta-regression analyses were performed to explore the effect of hepatitis B viral status, microvascular invasion, type of resection (anatomic vs. parenchymal-sparing), and tumor size on the outcomes. Ten eligible RCTs, reporting on 1216 patients in total, were identified. The combination of hepatectomy and adjuvant TACE was associated with superior OS (hazard ratio (HR): 0.66, 95% confidence interval (CI): 0.52 to 0.85; p < 0.001) and RFS (HR: 0.70, 95% CI: 0.56 to 0.88; p < 0.001) compared to hepatectomy alone. There were significant concerns regarding the risk of bias in most of the included studies. Overall, adjuvant TACE may be associated with an oncologic benefit in select HCC patients. However, the applicability of these findings may be limited to Eastern Asian populations, due to the geographically restricted sample. High-quality multinational RCTs, as well as predictive tools to optimize patient selection, are necessary before adjuvant TACE can be routinely implemented into standard practice. PROSPERO Registration ID: CRD42021245758.

Download Full-text

Efficacy of hydrofibre dressing following total joint arthroplasty: a meta-analysis of randomised controlled trials

Hip International ◽

10.1177/11207000211012669 ◽

2021 ◽

pp. 112070002110126

Author(s):

Raman Mundi ◽

Harman Chaudhry ◽

Seper Ekhtiari ◽

Prabjit Ajrawat ◽

Daniel M Tushinski ◽

...

Keyword(s):

Systematic Review ◽

Total Joint Arthroplasty ◽

Meta Analysis ◽

Joint Infection ◽

The United States ◽

Joint Arthroplasty ◽

Cochrane Library ◽

Controlled Trials ◽

Observable Effect ◽

The Impact

Introduction: In the United States, over 1,000,000 total joint arthroplasty (TJA) surgeries are performed annually and has been forecasted that this number will exceed 4,000,000 by the year 2030. Many different types of dressing exist for use in TJA surgery, and it is unclear if any of the newer, hydrofibre dressings are superior to traditional dressings at reducing rates of infections or improving wound healing. Thus, the aim of this systematic review and meta-analysis was to assess the impact of hydrofiber dressings on reducing complications. Methods: A systematic review and meta-analysis was performed using the online databases MEDLINE and the Cochrane Library. Randomized controlled trials (RCTs) comparing hydrofibre dressings to a standard dressing were included. Summary measures are reported as odds ratios (ORs) and mean differences (MDs) with 95% confidence intervals (CIs). Our primary outcome was prosthetic joint infection (PJI). Secondary outcomes included blisters, dressing changes and wound irritation. Results: 5 RCTs were included. Hydrofibre dressing had no observable effect on PJI or wound irritation (OR 0.53; 95% CI, 0.14–1.98; p = 0.35). Hydrofibre dressings reduced the rate of blisters (OR 0.36; 95% CI, 0.14–0.90; p = 0.03) and number of dressing changes (MD -1.89; 95% CI, -2.68 to -1.11). Conclusions: In conclusion, evidence suggests hydrofibre dressings have no observable effect on PJI and wound irritation. Evidence for reduction in blisters and number of dressings is modest given wide CIs and biased trial methodologies. Use of hydrofibre dressings should be considered inconclusive for mitigating major complications in light of current best evidence.

Download Full-text

Executive functions in children with heart disease: a systematic review and meta-analysis

Cardiology in the Young ◽

10.1017/s1047951121001074 ◽

2021 ◽

pp. 1-9

Author(s):

William M. Jackson ◽

Nicholas Davis ◽

Johanna Calderon ◽

Jennifer J. Lee ◽

Nicole Feirsen ◽

...

Keyword(s):

Systematic Review ◽

Executive Functions ◽

Data Extraction ◽

Meta Analysis ◽

Executive Dysfunction ◽

Cochrane Library ◽

Planning Problem ◽

Healthy Controls ◽

Cross Sectional ◽

Increased Risk

Abstract Context: People with CHD are at increased risk for executive functioning deficits. Meta-analyses of these measures in CHD patients compared to healthy controls have not been reported. Objective: To examine differences in executive functions in individuals with CHD compared to healthy controls. Data sources: We performed a systematic review of publications from 1 January, 1986 to 15 June, 2020 indexed in PubMed, CINAHL, EMBASE, PsycInfo, Web of Science, and the Cochrane Library. Study selection: Inclusion criteria were (1) studies containing at least one executive function measure; (2) participants were over the age of three. Data extraction: Data extraction and quality assessment were performed independently by two authors. We used a shifting unit-of-analysis approach and pooled data using a random effects model. Results: The search yielded 61,217 results. Twenty-eight studies met criteria. A total of 7789 people with CHD were compared with 8187 healthy controls. We found the following standardised mean differences: −0.628 (−0.726, −0.531) for cognitive flexibility and set shifting, −0.469 (−0.606, −0.333) for inhibition, −0.369 (−0.466, −0.273) for working memory, −0.334 (−0.546, −0.121) for planning/problem solving, −0.361 (−0.576, −0.147) for summary measures, and −0.444 (−0.614, −0.274) for reporter-based measures (p < 0.001). Limitations: Our analysis consisted of cross-sectional and observational studies. We could not quantify the effect of collinearity. Conclusions: Individuals with CHD appear to have at least moderate deficits in executive functions. Given the growing population of people with CHD, more attention should be devoted to identifying executive dysfunction in this vulnerable group.

Download Full-text

Efficacy and safety of omalizumab in chronic rhinosinusitis with nasal polyps: a systematic review and meta-analysis of randomised controlled trials

BMJ Open ◽

10.1136/bmjopen-2020-047344 ◽

2021 ◽

Vol 11 (9) ◽

pp. e047344

Author(s):

Qingwu Wu ◽

Lianxiong Yuan ◽

Huijun Qiu ◽

Xinyue Wang ◽

Xuekun Huang ◽

...

Keyword(s):

Systematic Review ◽

Adverse Events ◽

Chronic Rhinosinusitis ◽

Randomised Controlled Trials ◽

Nasal Polyps ◽

Meta Analysis ◽

Cochrane Library ◽

Controlled Trials ◽

Efficacy And Safety ◽

Randomised Controlled

ObjectivesTo assess the efficacy and safety of omalizumab for chronic rhinosinusitis with nasal polyps (CRSwNP) and to identify evidence gaps that will guide future research on omalizumab for CRSwNP.DesignSystematic review and meta-analysis.Data sourcesA comprehensive search was performed in PubMed, Embase, Web of Science and the Cochrane Library on 13 October 2020.Eligibility criteriaRandomised controlled trials (RCTs) comparing omalizumab with placebo, given for at least 16 weeks in adult patients with CRSwNP.Data extraction and synthesisTwo independent authors screened search results, extracted data and assessed studies using the Cochrane risk of bias tool. Data were pooled using the inverse-variance method and expressed as mean differences (MDs) with 95% CIs. Heterogeneity was assessed by the χ2 test and the I2 statistic.ResultsA total of four RCTs involving 303 participants were identified. When comparing omalizumab to placebo, there was a significant difference in Nasal Polyps Score (MD=−1.20; 95% CI −1.48 to −0.92), Nasal Congestion Score (MD=−0.67; 95% CI −0.86 to −0.48), Sino-Nasal Outcome Test-22 (MD=−15.62; 95% CI −19.79 to −11.45), Total Nasal Symptom Score (MD=−1.84; 95% CI −2.43 to −1.25) and reduced need for surgery (risk ratio (RR)=5.61; 95% CI 1.99 to 15.81). Furthermore, there was no difference in the risk of serious adverse events ((RR=1.40; 95% CI 0.29 to 6.80), adverse events (RR=0.83; 95% CI 0.60 to 1.15) and rescue systemic corticosteroid (RR=0.52; 95% CI 0.17 to 1.61).ConclusionsThis was the first meta-analysis that identified omalizumab significantly improved endoscopic, clinical and patient-reported outcomes in adults with moderate to severe CRSwNP and it was safe and well tolerated.PROSPERO registration numberCRD42020207639.

Download Full-text

Impact of PCSK9 monoclonal antibodies on circulating hs-CRP levels: a systematic review and meta-analysis of randomised controlled trials

BMJ Open ◽

10.1136/bmjopen-2018-022348 ◽

2018 ◽

Vol 8 (9) ◽

pp. e022348 ◽

Cited By ~ 20

Author(s):

Ye-Xuan Cao ◽

Sha Li ◽

Hui-Hui Liu ◽

Jian-Jun Li

Keyword(s):

Systematic Review ◽

Treatment Duration ◽

Randomised Controlled Trials ◽

Familial Hypercholesterolaemia ◽

Meta Analysis ◽

Cochrane Library ◽

Controlled Trials ◽

Participant Characteristics ◽

Hs Crp ◽

Randomised Controlled

ObjectiveTo evaluate the potential effects of proprotein convertase subtilisin/kexin type 9 monoclonal antibody (PCSK9-mAb) on high-sensitivity C reactive protein (hs-CRP) concentrations.DesignA systematic review and meta-analysis of randomised controlled trials.Data sourcesPubMed, MEDLINE, the Cochrane Library databases, ClinicalTrials.gov and recent conferences were searched from inception to May 2018.Eligibility criteria for selecting studiesAll randomised controlled trials that reported changes of hs-CRP were included.ResultsTen studies involving 4198 participants were identified. PCSK9-mAbs showed a slight efficacy in reducing hs-CRP (−0.04 mg/L, 95% CI: −0.17 to 0.01) which was not statistically different. The results did not altered when subgroup analyses were performed including PCSK9-mAb types (alirocumab: 0.12 mg/L, 95% CI: −0.18 to 0.43; evolocumab: 0.00 mg/L, 95% CI: −0.07 to 0.07; LY3015014: −0.48 mg/L, 95% CI: −1.28 to 0.32; RG7652: 0.35 mg/L, 95% CI: −0.26 to 0.96), treatment duration (≤12w: 0.00 mg/L, 95% CI: −0.07 to 0.07; >12w: −0.11 mg/L, 95% CI: −0.45 to −0.23), participant characteristics (familial hypercholesterolaemia: 0.00 mg/L, 95% CI: −0.07 to 0.07; non-familial hypercholesterolaemia: 0.07 mg/L, 95% CI: −0.12 to 0.26; mix: −0.48 mg/L, 95% CI: −1.28 to 0.32) and treatment methods (monotherapy: 0.00 mg/L, −0.08 to 0.07; combination therapy: −0.08 mg/L, −0.37 to 0.21). Meta-regression analyses suggested no significant linear correlation between baseline age (p=0.673), sex (p=0.645) and low-density lipoprotein cholesterol reduction (p=0.339).ConclusionsOur updated meta-analysis suggested that PCSK9-mAbs had no significant impact on circulating hs-CRP levels irrespective of PCSK9-mAb types, participant characteristics and treatment duration or methods.

Download Full-text

Therapeutic effect of resveratrol supplementation on oxidative stress: a systematic review and meta-analysis of randomised controlled trials

Postgraduate Medical Journal ◽

10.1136/postgradmedj-2019-136415 ◽

2019 ◽

Vol 96 (1134) ◽

pp. 197-205 ◽

Cited By ~ 2

Author(s):

Mehdi Koushki ◽

Mostafa Lakzaei ◽

Hadi Khodabandehloo ◽

Hossein Hosseini ◽

Reza Meshkani ◽

...

Keyword(s):

Oxidative Stress ◽

Systematic Review ◽

Publication Bias ◽

Randomised Controlled Trials ◽

Meta Analysis ◽

Cochrane Library ◽

Controlled Trials ◽

Oxidative Markers ◽

Markers Of Oxidative Stress ◽

Randomised Controlled

BackgroundResveratrol is a naturally occurring polyphenol compound mainly found in grapes and red wine. The evidence has suggested that resveratrol has an antioxidant effect. However, the results are inconsistent and inconclusive. Thus, we conducted a systematic review and meta-analysis to evaluate the effect of resveratrol supplementation on markers of oxidative stress.MethodsWe searched PubMed, ISI Web of Science, EMBASE, Scopus and the Cochrane library up to December 2018 to identify randomised controlled trials (RCTs) assessing resveratrol supplementation effects on oxidative markers. Heterogeneity, publication bias, risk of bias and subgroup analysis were analysed. This meta-analysis was conducted in accordance with the guidelines of the Preferred ReportingItems for Systematic Reviews and Meta-Analysis (PRISMA).ResultsMeta-analysis of data from 12 RCTs did not support significant effect of resveratrol supplementation on circulating levels of superoxide dismutase (SOD) (standardized mean difference (SMD) (1.12), (95% CI −0.91 to 3.1), p=0.28), catalase (CAT) (SMD (−0.07), (95% CI −1.4 to 1.3), p=0.92) and glutathione peroxidase (GPx) (SMD (−0.76), (95% CI −2.56 to 1.04), p=0.40). Although, resveratrol supplementation increased significantly circulating total antioxidant capacity (TAC) concentrations (SMD (0.52), (95% CI −0.02 to 1.07), p=0.05). Severe heterogeneity was observed between studies, and no obvious publication bias was observed in included RCTs.ConclusionCollectively, our findings of available RCTs did no show any benefit of resveratrol supplementation on SOD, CAT and GPx except for TAC. Well-designed RCTs are necessary to confirm these results.

Download Full-text

Serum Sclerostin Levels in Patients with Ankylosing Spondylitis and Rheumatoid Arthritis: A Systematic Review and Meta-Analysis

BioMed Research International ◽

10.1155/2017/9295313 ◽

2017 ◽

Vol 2017 ◽

pp. 1-7 ◽

Cited By ~ 7

Author(s):

Jianfeng Shi ◽

Haijian Ying ◽

Juping Du ◽

Bo Shen

Keyword(s):

Rheumatoid Arthritis ◽

Systematic Review ◽

Ankylosing Spondylitis ◽

Meta Analysis ◽

Cochrane Library ◽

Healthy Controls ◽

Data Analyses ◽

Standard Mean Difference ◽

The Difference ◽

Sclerostin Level

Objective. Current studies of serum sclerostin levels in AS and RA patients are inconsistent. This meta-analysis was performed to identify the association of serum sclerostin level with AS and RA patients. Methods. Embase, PubMed, MEDLINE, and Cochrane Library databases (up to 25 January 2017) were used to collect all relevant published articles. Studies were pooled and standard mean difference (SMD) with 95% confidence interval (CI) was calculated. All data analyses were performed using RevMan 5.3. Results. Totally eight studies of AS including 420 AS patients and 317 healthy controls (HC) and three studies of RA including 145 RA patients and 127 HC were finally included in this meta-analysis. The results revealed that the serum sclerostin levels in both AS patients (SMD=-0.14; 95% CI=[-0.39,0.11]; P=0.28) and RA patients (SMD=-0.10; 95% CI=[-0.34,0.15]; P=0.43) were not significantly different from those in HC. Conclusion. The difference of serum sclerostin levels in AS and RA patients was not significantly different from HC, indicating that the sclerostin may not associate with the development of AS and RA.

Download Full-text

Zinc Supplementation and Body Weight: A Systematic Review and Dose–Response Meta-analysis of Randomized Controlled Trials

Advances in Nutrition ◽

10.1093/advances/nmz084 ◽

2019 ◽

Cited By ~ 2

Author(s):

Shima Abdollahi ◽

Omid Toupchian ◽

Ahmad Jayedi ◽

David Meyre ◽

Vivian Tam ◽

...

Keyword(s):

Systematic Review ◽

Body Weight ◽

Randomized Controlled Trials ◽

Dose Response ◽

Zinc Supplementation ◽

Meta Analysis ◽

Cochrane Library ◽

Controlled Trials ◽

Anthropometric Measures ◽

Randomized Controlled

ABSTRACT The aim of this study was to determine the effect of zinc supplementation on anthropometric measures. In this systematic review and dose–response meta-analysis, we searched PubMed, Scopus, ISI Web of Science, and the Cochrane Library from database inception to August 2018 for relevant randomized controlled trials. Mean differences and SDs for each outcome were pooled using a random-effects model. Furthermore, a dose–response analysis for zinc dosage was performed using a fractional polynomial model. Quality of evidence was evaluated using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. Twenty-seven trials (n = 1438 participants) were included in the meta-analysis. There were no significant changes in anthropometric measures after zinc supplementation in the overall analysis. However, subgroup analyses revealed that zinc supplementation increased body weight in individuals undergoing hemodialysis (HD) [3 trials, n = 154 participants; weighted mean difference (WMD) = 1.02 kg; 95% CI: 0.38, 1.65 kg; P = 0.002; I2 = 11.4%] and decreased body weight in subjects who are overweight/obese but otherwise healthy (5 trials, n = 245 participants; WMD = −0.55 kg; 95% CI: −1.06, −0.04 kg; P = 0.03; I2 = 31.5%). Dose–response analyses revealed a significant nonlinear effect of supplementation dosage on BMI (P = 0.001). Our data suggest that zinc supplementation increases body weight in patients undergoing HD and decreases body weight in individuals who are overweight/obese but otherwise healthy, although after normalization for study duration, the association observed in subjects who are overweight/obese disappeared. Although more high-quality studies are needed to reach a definitive conclusion, our study supports the view that zinc may be associated with body weight.

Download Full-text

The effect of l-arginine supplementation on lipid profile: a systematic review and meta-analysis of randomised controlled trials

British Journal Of Nutrition ◽

10.1017/s0007114519001855 ◽

2019 ◽

Vol 122 (9) ◽

pp. 1021-1032

Author(s):

Amir Hadi ◽

Arman Arab ◽

Sajjad Moradi ◽

Ana Pantovic ◽

Cain C. T. Clark ◽

...

Keyword(s):

Systematic Review ◽

Lipid Profile ◽

Randomised Controlled Trials ◽

Weighted Mean Difference ◽

Meta Analysis ◽

Cochrane Library ◽

Controlled Trials ◽

Inconsistency Index ◽

Randomised Controlled ◽

Arginine Supplementation

AbstractA number of clinical trials have examined the effect of l-arginine on lipid profile in recent years; however, the results remain equivocal. Therefore, the present study aims to summarise and quantitatively examine the available evidence on the effectiveness l-arginine supplementation on lipid parameters using a systematic review and meta-analytic approach. Online databases including PubMed, Scopus, ISI Web of Science, Cochrane Library and Google Scholar were searched up to April 2019 for randomised controlled trials that examined the effect of l-arginine supplementation on lipid profile in adults. Treatment effects were expressed as weighted mean difference (WMD) and the corresponding standard error in concentrations of serum lipids. To estimate the overall effect of l-arginine supplementation, we used the random-effects model. In total, twelve studies were included in the systematic review. The meta-analysis revealed that l-arginine supplementation did not significantly change the concentrations of total cholesterol (WMD: –5·03 mg/dl; 95 % CI –10·78, 0·73; P = 0·08; inconsistency index (I2) = 39·0 %), LDL (WMD: –0·47 mg/dl; 95 % CI –3·61, 2·66; P = 0·76; I2 = 0·0 %), or HDL (WMD: 0·57 mg/dl; 95 % CI –1·28, 2·43; P = 0·54; I2 = 68·4 %). A significant reduction was observed only in serum TAG levels (WMD: –7·04 mg/dl; 95 % CI –11·42, –2·67; P < 0·001; I2 = 0·0 %). This meta-analysis concludes that l-arginine supplementation can significantly reduce blood TAG levels; however, there is insufficient evidence to support its hypocholesterolaemic effects. To draw straightforward conclusions regarding generalised recommendations for l-arginine supplementation for improving lipid profile, there is a need for more well-controlled trials targeting exclusively patients with dyslipidaemia.

Download Full-text