Trial Sequential Analysis explained using a post-hoc analysis of meta-analyses published in Korean Journal of Anesthesiology

Mortality in Critically Ill Patients with Liberal Versus Restrictive Transfusion Thresholds: A Systematic Review and Meta-Analysis of Randomized Controlled Trials with Trial Sequential Analysis

Background/Objectives: Anemia is common in critically ill patients, yet red blood cell (RBC) transfusion without active bleeding does not consistently improve outcomes and carries risks such as pulmonary injury, fluid overload, and increased costs. Optimal transfusion thresholds remain debated, with some guidelines recommending a restrictive target of 7 g/dL instead of a more liberal target of 9 g/dL. Methods: We conducted a systematic review and meta-analysis following PRISMA guidelines, searching PubMed, EMBASE, and LILACS from January 1995 to October 2024. Thirteen randomized controlled trials involving 13,705 critically ill adults were included, with 6855 assigned to liberal and 6850 to restrictive transfusion strategies. The risk of bias was assessed using the Cochrane Risk of Bias Tool 2, and the pooled effect sizes were estimated with a random-effects model. We registered the protocol in PROSPERO International Prospective Register of Systematic Reviews (CDR42024589225). Results: No statistically significant difference was observed in 30-day mortality between restrictive and liberal strategies (odds ratio [OR] 1.02; 95% confidence interval [CI], 0.83-1.25; I2 = 49%). Similarly, no significant differences emerged for the 90-day or 180-day mortality, hospital or intensive care unit (ICU) length of stay, dialysis requirement, or incidence of acute respiratory distress syndrome (ARDS). However, patients in the restrictive group received significantly fewer RBC units. The trial sequential analysis (TSA) indicated that the evidence accrued was insufficient to definitively confirm or exclude an effect on the 30-day mortality, as the required sample size was not reached. Conclusions: In conclusion, while our meta-analysis found no statistically significant difference in the short-term mortality between restrictive and liberal transfusion strategies, larger trials are needed to fully determine whether any clinically meaningful difference exists in critically ill populations.

Hypouricemic effect of sodium glucose transporter-2 inhibitors: a network meta-analysis and meta-regression of randomized clinical trials

BACKGROUND

Sodium-glucose cotransporter-2 inhibitors (SGLT2is) are known for their cardiovascular benefits, but their impact on serum uric acid levels is not well understood. This study evaluates the hypouricemic effects of SGLT2is and their potential cardiovascular implications.

METHODS

A network meta-analysis was performed, including 56 studies (16,788 participants) contributing data to the meta-analysis. The effects of SGLT2is on serum uric acid levels were analyzed with weighted mean difference (WMD) as the effect estimate. Bootstrapped meta-analysis, trial sequential analysis, and meta-regression were utilized to validate the findings and assess the influence of covariates. The certainty of the evidence was evaluated.

RESULTS

The analysis revealed that SGLT2is significantly reduced serum uric acid levels (WMD: -40.01 μmol/L). Specific reductions were noted for ertugliflozin (-42.17 μmol/L), dapagliflozin (-40.28 μmol/L), empagliflozin (-46.75 μmol/L), canagliflozin (-35.55 μmol/L), and ipragliflozin (-10.48 μmol/L). Both low and high doses were effective, with empagliflozin showing the highest efficacy. No significant associations were found with covariates. The evidence was of moderate certainty.

CONCLUSION

SGLT2is significantly lower serum uric acid levels, with empagliflozin being the most effective. These findings suggest a potential role in reducing cardiovascular risk. Further research is needed to explore their effects on hyperuricemic patients, and monitoring serum uric acid levels is recommended.

Chinese herbal medicine for the treatment of children with cerebral palsy: a meta-analysis of randomized controlled trials with core herbs exploration

Introduction

Chinese herbal medicine (CHM) taken orally is frequently utilized to enhance functional ability and independence in cerebral palsy (CP); nonetheless, there is a lack of current evidence regarding the efficacy of oral CHM in treating CP. Additionally, the general complexities of CHM prescriptions often obscure the underlying mechanisms. Our study aims to assess the efficacy of oral CHM in treating CP, a meta-analysis will be conducted on randomized clinical trials (RCTs).

Materials and methods

We searched Cochrane Library, PubMed, Embase, Scopus, PubMed Central, ClinicalTrials.gov, and China National Knowledge Infrastructure (CNKI), from 1990 to 2022. The primary outcome was the improvement in Effectiveness rate (ER). The secondary outcome was the improvement of motor function (GMFM). Subgroup analysis and trial sequential analysis (TSA) were conducted to confirm results consistency. Core CHMs were investigated through system pharmacology analysis.

Results

Seventeen RCTs were analyzed, in which CHMs with Standard treatment (ST) were compared to ST alone. All participants were aged <11 years. More participants in the CHM group achieved prominent improvement in ER (RR: 1.21, 95% CI: 1.13-1.30, p-value < 0.001, I2 = 32%) and higher GMFM improvement (SMD: 1.49; 95% CI: 1.33-1.65, p-value < 0.001, I2 = 92%). TSA also showed similar results with proper statistical power. Core CHMs, such as Glycyrrhiza uralensis Fisch. Ex DC., Poria cocos (Schw.) Wolf, Paeonia lactiflora Pall., processed Rehmannia glutinosa (Gaertn.) DC., Astragalus mongholicus Bunge, and Angelica sinensis (Oliv.) Diels, exerted effects on immune modulation and metabolism systems. The subgroup analysis showed participants using core CHMs or longer CHM treatment duration, and studies enrolling CP with spastic or mixed type, or mild-to-moderate severity had better outcomes in CHM groups with less heterogeneity.

Conclusion

CHMs may have a positive impact on managing pediatric CP; however, the potential bias in study design should be improved.

Systematic Review Registration

Identifier CRD42023424754.

Preoperative botulinum toxin for complex abdominal wall reconstruction: a meta-analysis of propensity-score matched studies with trial sequential analysis

PURPOSE

Large ventral hernias can be associated with significant loss of domain, and preoperative Botulinum Toxin A (BTA) has been suggested as an adjunct therapy to minimize the effects of ventral hernia repair and facilitate fascial closure. However, there is often bias in studies involving BTA and its use is associated with significant cost and its efficacy remains unclear.

METHODS

We systematically searched Medline, Embase, Cochrane, and ClinicalTrial.gov for propensity-score matched (PSM) studies comparing preoperative BTA and AWR with standard AWR for complex hernias. We pooled odds ratios (ORs) and mean differences with 95% confidence intervals (CIs) to assess outcomes, applying a random-effects model. We used R studio version 4.3.1 for statistical analyses.

RESULTS

We included six studies with PSM comprising 851 patients undergoing AWR. The mean age was 60.5 years, mean BMI was 31.8 kg/m2, and 46.5% of patients were male. There were no significant differences between groups regarding fascial closure rate (OR 1.54; 95% CI 0.78 to 3.05; p = 0.21), hernia recurrence (OR 0.81; 95% CI 0.33 to 2.01; p = 0.65), component separation (OR 1.50; 95% CI 0.54 to 4.14 p = 0.4), surgical site infections and occurrences (OR 1.31; 95% CI 0.34 to 5.00; p = 0.70), length of hospital stay, or operation time. The Trial Sequential Analysis (TSA) indicated that none of the outcomes reached the necessary sample size for a definitive conclusion.

CONCLUSIONS

Preoperative BTA did not offer significant benefits in AWR of complex incisional hernia repairs. However, TSA showed that the required sample size was not achieved.

EUS-guided coiling plus glue injection compared with endoscopic glue injection alone in endoscopic treatment for gastric varices: a systematic review and meta-analysis

BACKGROUND AND AIMS

EUS-guided coil plus glue injection has emerged as a safe and effective modality for gastric varices (GVs). Very few studies have compared EUS embolization with the direct endoscopic glue injection (EGI) technique for its safety and effectiveness. In this systematic review and meta-analysis, we compared the outcomes of EUS-guided coil plus glue injection versus EGI.

METHODS

MEDLINE, EMBASE, and Cochrane databases were searched for studies that compared EUS and EGI for GVs, and 1454 articles were screened following the Preferred Reporting Items for Systematic reviews and Meta-Analyses protocol. Endpoints were pulmonary embolism, recurrent bleeding rate, reintervention rate, technical success, abdominal pain, and mortality rate. A restricted maximum likelihood random-effects model with odds ratios (ORs) and 95% confidence intervals (CIs) was used for binary endpoints. Heterogeneity was evaluated through Cochrane's Q statistic and Higgins and Thompson's I2 statistic. Significance was defined as P < .05.

RESULTS

We included 6 studies with 445 patients treated for GVs. Mean patient age was 49 years, and 43% were women. EUS was associated with a reduction in recurrent bleeding rate (OR, .22; 95% CI, .11-.45; P < .001; I2 = 0) and reintervention rate (OR, .29; 95% CI, .09-.89; P = .03; I2 = 49%) compared with EGI. There were no differences between groups in pulmonary embolism (OR, .34; 95% CI, .10-1.18; P = .09; I2 = 0%), mortality rate (OR, .78; 95% CI, .28-2.13; P = .63; I2 = 0%), technical success (OR, 3.50; 95% CI, .60-20.49; P = .16; I2 = 0%), fever (OR, 1.49; 95% CI, .42-5.21 days; P = .5; I2 = 0%), and abdominal pain (OR, .96; 95% CI, .31-2.95; P = .94; I2 = 32%).

CONCLUSIONS

In patients with GVs, EUS-guided coil plus glue injection is associated with lower recurrent bleeding and reintervention rates than EGI with no difference in pulmonary embolization rate, abdominal pain, technical success, and mortality rate.

Genetic Association of the Ins/Del Variant of ACE and Risk of Cardiomyopathy: A Case-Control Study and Updated Meta-Analysis

INTRODUCTION

Cardiomyopathy is a complex condition influenced by multiple genes and environmental factors. It has been suspected that cardiomyopathy is affected by the ACE gene's I/D polymorphism. Our study aimed to evaluate the association between this polymorphism and cardiomyopathy risk in the Jammu population of North India, alongside a meta-analysis to determine the specific risks associated with different types of cardiomyopathy.

METHOD

In the case-control study, we opted for a convenient sampling technique to gather patients from hospitals. Meanwhile, for the meta-analysis registered under PROSPERO with CRD42024519763, and in line with PRISMA guidelines, we accessed online databases and applied predefined inclusion criteria. Data extraction and quality assessment were performed using the Newcastle-Ottawa scale. Statistical analysis included genotypic frequencies, Hardy-Weinberg equilibrium testing, logistic regression models, and assessments for heterogeneity and publication bias.

RESULT

The case-control study revealed a significant association between the ACE I/D risk variant and cardiomyopathy risk in the Jammu population (odds ratio [OR]: 1.30, confidence interval [CI] [1.04-1.63], p value = 0.021). Furthermore, a total of 34 studies were fund-eligible for the meta-analysis and demonstrated a significant association between the risk variant and both dilated (OR: 1.25, CI [1.03-1.50], p value = 0.022) and hypertrophic (OR: 1.31, CI [1.0876-1.5776], p value = 0.004446) cardiomyopathy.

CONCLUSION

Our study found a significant association between the I/D polymorphism and cardiomyopathy risk in the Jammu population. Further, the meta-analysis strengthens the findings by consistently linking the ACE I/D polymorphism to both dilated and hypertrophic cardiomyopathy. These results underscore the importance of genetic factors in cardiomyopathy risk assessment and further research is needed to understand the underlying mechanisms and potential therapeutic implications.

Krill oil supplementation for knee pain: a systematic review and meta-analysis with trial sequential analysis of randomized controlled trials

INTRODUCTION

Knee pain is a major cause of disability worldwide, particularly among the elderly. Current treatments, including nonsteroidal anti-inflammatory drugs and analgesics, often lead to adverse effects. Krill oil is being explored as a potential alternative, however its efficacy in managing knee symptoms remains unclear.

METHODS

MEDLINE, Embase, and Cochrane databases were searched until May 2024 for studies comparing krill oil and placebo in knee pain patients. Endpoints included knee pain, stiffness, physical function, and lipid profiles (HDL-C, LDL-C, triglycerides, and total cholesterol). A restricted maximum likelihood random-effects model with standardized mean differences (SMD) and 95% confidence intervals (CI) was used. A trial sequential analysis was conducted to evaluate further research implications.

RESULTS

We included five trials with 700 patients using krill oil for knee pain. Results showed no significant difference between krill oil and placebo for knee pain, knee stiffness, and lipid profiles. However, krill oil demonstrated a significant small effect in improving knee physical function (SMD -0.24, 95% CI [-0.41; -0.08], I2 = 0%).Trial sequential analysis provided certainty that krill oil enhances knee physical function compared to placebo and indicated no improvement in knee pain, but the findings for knee stiffness need to be confirmed by further research.

CONCLUSION

This study found that krill oil supplementation did not significantly improve knee pain, stiffness, or lipid profile, although it may help knee physical function. Based on these findings, krill oil supplementation is not yet justified for knee pain.

Effectiveness of Adaptive Support Ventilation in Facilitating Weaning from Mechanical Ventilation in Postoperative Patients

OBJECTIVE

This meta-analysis aims to evaluate the effectiveness of adaptive support ventilation (ASV) in facilitating postoperative weaning from mechanical ventilation in cardiac surgery patients.

DESIGN

A systematic review and meta-analysis to assess ASV in weaning postoperative cardiac surgery patients. Outcomes included early extubation, reintubation rates, time to extubation, and lengths of intensive care units and hospital stays.

SETTING

We searched electronic databases from inception to March 2023 and included randomized controlled trials that compared ASV with conventional ventilation methods in this population.

PARTICIPANTS

Postoperative cardiac surgery patients.

MEASUREMENTS AND MAIN RESULTS

A random effects model was used for meta-analysis, and trial sequential analysis (TSA) was conducted to assess result robustness. The meta-analysis included 11 randomized controlled trials with a total of 1027 randomized patients. ASV was associated with a shorter time to extubation compared to conventional ventilation (random effects, mean difference -68.30 hours; 95% confidence interval, -115.50 to -21.09) with TSA providing a conclusive finding. While ASV indicated improved early extubation rates, no significant differences were found in reintubation rates or lengths of intensive care unit and hospital stays, with these TSA results being inclusive.

CONCLUSIONS

ASV appears to facilitate a shorter time to extubation in postoperative cardiac surgery patients compared to conventional ventilation, suggesting benefits in accelerating the weaning process and reducing mechanical ventilation duration.

Photobiomodulation efficacy in age-related macular degeneration: a systematic review and meta-analysis of randomized clinical trials

BACKGROUND

Age-related macular degeneration (AMD) is a leading cause of vision loss. Photobiomodulation (PBM) offers a controversial approach for managing dry AMD, aiming to halt or reverse progression through mitochondrial activity modulation. However, the efficacy and clinical relevance of PBM as a potential approach for managing dry AMD remain debated.

METHODS

We systematically searched PubMed, Embase, and Cochrane databases for randomized controlled trials (RCTs) comparing PBM versus a sham in patients with dry AMD. We performed trial sequential analysis (TSA) and minimal clinically important difference (MCID) calculations to assess statistical and clinical significance applying a random-effects model with 95% confidence intervals (CI).

RESULTS

We included three RCTs comprising 247 eyes. The pooled analysis showed that PBM significant improved BCVA (MD 1.76 letters; 95% CI: 0.04 to 3.48) and drusen volume (MD -0.12 mm³; 95% CI: -0.22 to -0.02) as compared with a sham control. However, the TSA indicated that the current sample sizes were insufficient for reliable conclusions. No significant differences were observed in GA area. The MCID analysis suggested that the statistically significant results did not translate into clinically significant benefits. In the quality assessment, all studies were deemed to have a high risk of bias.

CONCLUSION

This meta-analysis points limitations in the current evidence base for PBM in dry AMD treatment, with issues around small sample sizes. Statistically significant improvements do not translate into clinical benefits. The research underscores need for larger RCTs to validate PBM's therapeutic potential for dry AMD.

Dual-task training in older adults with cognitive impairment: A meta-analysis and trial sequential analysis of randomized controlled trials

OBJECTIVE

To determine the effects of simultaneous dual-task training on cognitive function, physical function, and depression in older adults with mild cognitive impairment or dementia.

METHODS

Comprehensive database searches were conducted in PubMed, Embase, the Cochrane Library, CINAHL, Ovid-Medline, Web of Science, and Scopus up to December 2022. Randomized controlled trials were included to assess the efficacy of simultaneous dual-task training for older adults with mild cognitive impairment or dementia. The analysis utilized Comprehensive Meta-Analysis version 3.0, presenting Hedges' g and the corresponding 95 % confidence interval (CI) for the pooled effect size and, applying a random-effects model. The I2 and Cochran's Q tests were employed to evaluate heterogeneity. The Cochrane Risk of Bias 2.0 tool was employed to assess study quality. The Copenhagen Trial Unit (version 0.9.5.10 Beta) was employed for trial sequential analysis, providing a rigorous methodology for evaluating cumulative evidence from multiple studies.

RESULTS

Of the 1676 studies identified, 20 studies involving 1477 older adults with cognitive impairment were included. Dual-task training significantly enhanced global cognition (0.477, 95 % CI: 0.282 to 0.671), executive function (-0.310, 95 % CI: -0.586 to -0.035), working memory (0.714, 95 % CI: 0.072 to 1.355), gait (0.418, 95 % CI: 0.252 to 0.583), physical activity (0.586, 95 % CI: 0.012 to 1.16), and depression (-0.703, 95 % CI: -1.253 to -0.153). Trial sequential analyses revealed the robustness of this meta-analysis, which was based on a sufficient sample size from the included studies. Moreover, dual-task training demonstrated beneficial effects on global cognition, executive function, working memory, and gait.

CONCLUSIONS

Dual-task training improved cognition, physical function, and depression among older adults with cognitive impairment. Accordingly, dual-task training should be considered a clinical nonpharmacological intervention for older adults with mild cognitive impairment or dementia. Nevertheless, the trial sequential analysis results were consistent with those of the pairwise meta-analysis but only global cognition reached significance by crossing the trial sequential analysis boundary. Future studies with higher-quality designs and larger sample sizes are required to obtain more conclusive results regarding other outcomes.

REGISTRATION

PROSPERO CRD42023418598.

Trial sequential analysis: A simple guide for judging the conclusiveness of the effect

Meta-analysis is a statistical method used in systematic reviews to provide a quantitative estimate of the effect. However, including very few studies and participants may increase the risk of spurious findings. Trial sequential analysis (TSA) has been introduced to enhance the robustness of meta-analysis. TSA is a cumulative meta-analysis method that weighs type I and II errors while estimating the effect. The application of TSA can lead to a more accurate estimation of the clinical effectiveness of the intervention. The aim of the present paper was to introduce the TSA to orthodontic clinicians and researchers using continuous data from an orthodontic systematic review.

Thorax support vest to prevent sternal wound infections in cardiac surgery patients-a systematic review and meta-analysis

OBJECTIVES

Midline sternotomy is the main surgical access for cardiac surgeries. The most prominent complication of sternotomy is sternal wound infection (SWI). The use of a thorax support vest (TSV) that limits thorax movement and ensures sternal stability has been suggested to prevent postoperative SWI.

METHODS

We performed a meta-analysis to evaluate differences in clinical outcomes with and without the use of TSV after cardiac surgery in randomized trials. The primary outcome was deep SWI (DSWI). Secondary outcomes were superficial SWI, sternal wound dehiscence, and hospital length of stay (LOS). A trial sequential analysis was performed. Fixed (F) and random effects (R) models were calculated.

RESULTS

A total of 4 studies (3820 patients) were included. Patients who wore the TSV had lower incidence of DSWI [odds ratio (OR) = F: 0.24, 95% confidence interval (CI), 0.13-0.43, P < 0.01; R: 0.24, 0.04-1.59, P = 0.08], sternal wound dehiscence (OR = F: 0.08, 95% CI, 0.02-0.27, P < 0.01; R: 0.10, 0.00-2.20, P = 0.08) and shorter hospital LOS (standardized mean difference = F: -0.30, -0.37 to -0.24, P < 0.01; R: -0.63, -1.29 to 0.02, P = 0.15). There was no difference regarding the incidence of superficial SWI (OR = F: 0.71, 95% CI, 0.34-1.47, P = 0.35; R: 0.64, 0.10, 4.26, P = 0.42). The trial sequential analysis, however, showed that the observed decrease in DSWI in the TSV arm cannot be considered conclusive based on the existing evidence.

CONCLUSIONS

This meta-analysis suggests that the use of a TSV after cardiac surgery could potentially be associated with a reduction in sternal wound complications. However, despite the significant treatment effect in the available studies, the evidence is not solid enough to provide strong practice recommendations.