Cumulative meta-analysis: What works

Synthetic vs. biologic mesh for abdominal wall reconstruction in contaminated surgical fields. A meta-analysis of randomized controlled trials and observational studies

PURPOSE

Biologic meshes had been the first choice for abdominal wall reconstruction (AWR) in contaminated surgical fields. However, due to increased cost and questioned effectiveness, synthetic meshes have been also implemented. The aim of the present meta-analysis was to compare synthetic and biologic mesh in terms of recurrence and postoperative outcomes.

METHODS

The present meta-analysis was designed using the PRISMA guidelines. A search in Medline, Scopus, EMBASE, Clinicaltrials.gov, Google Scholar and Cochrane CENTRAL was conducted from inception until September 2024. Randomized clinical trials (RCTs) and observational studies which compared the use of biologic and synthetic mesh for AWR in contaminated surgical fields were included. Data were extracted by two experienced researchers in pre-defined electronic forms. Pooled odds ratios (OR) and mean differences (MD) were calculated using a random-effects model. Included RCTs were assessed using the Risk of Bias 2 (RoB2) tool and non-randomized trials with the Risk of Bias in non-Randomized Trials (RoBINS-I) tool.

RESULTS

Overall 11 studies were included which enrolled 1,945 patients. Subgroup analysis of RCTs indicated significantly lower recurrence rates for synthetic compared to biologic mesh (p < 0.0001) with a similar follow-up (p = 0.07). Nevertheless, no difference was demonstrated in surgical site infection (SSI) rates. Although synthetic mesh was associated with shorter length of stay, the other postoperative outcomes (surgical site occurrences, mesh infections, readmissions, reoperations) were similar among the two groups.

CONCLUSION

Synthetic mesh should be considered as a safe and effective option for abdominal wall reconstruction in contaminated surgical fields compared to biologic mesh. Nevertheless, future research is expected to investigate cost-effectiveness of biosynthetic meshes, as alternative option in such surgical fields.

Rhythm vs Rate Control Strategy for Atrial Fibrillation: A Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Rhythm control, either with antiarrhythmic drugs or catheter ablation, and rate control strategies are the cornerstones of atrial fibrillation (AF) management. Despite the increasing role of rhythm control over the past few years, it remains inconclusive which strategy is superior in improving clinical outcomes.

OBJECTIVES

This study summarizes the total and time-varying evidence regarding the efficacy of rhythm- vs rate-control strategies in the management of AF.

METHODS

We systematically perused the MEDLINE, CENTRAL (Cochrane Central Register of Controlled Trials), and Web of Science databases for randomized controlled trials from inception to November 2023. We included studies that compared the efficacy of rhythm control (ie, antiarrhythmic drugs classes Ia, Ic, or III, AF catheter ablation, and electrical cardioversion) and rate control (ie, beta-blocker, digitalis, or calcium antagonist) strategies among patients with nonvalvular AF. The primary outcome was cardiovascular (CV) death, whereas secondary outcomes included all-cause death, stroke, hospitalization for heart failure (HF), sinus rhythm at the end of the follow-up, and rhythm control-related adverse events. A cumulative meta-analysis to assess temporal trends and a meta-regression analysis using the percentage of ablation use was performed.

RESULTS

We identified 18 studies with a total of 17,536 patients (mean age: 68.6 ± 9.7 years, 37.9% females) and a mean follow-up of 28.5 months. Of those, 31.9% had paroxysmal AF. A rhythm control strategy reduced CV death (HR: 0.78; 95% CI: 0.62-0.96), stroke (HR: 0.801; 95% CI: 0.643-0.998), and hospitalization for HF (HR: 0.80; 95% CI: 0.69-0.94) but not all-cause death (HR: 0.86; 95% CI: 0.73-1.02) compared with a rate control strategy. This benefit was driven by contemporary studies, whereas more ablation use within the rhythm control arm was associated with improved outcomes, except stroke.

CONCLUSIONS

In patients with AF, a contemporary rhythm control strategy leads to reduced CV mortality, HF events, and stroke compared with a rate control strategy.

Assessment of temporal instability in the applied ecology and conservation evidence base

Outcomes of meta-analyses are increasingly used to inform evidence-based decision making in various research fields. However, a number of recent studies have reported rapid temporal changes in magnitude and significance of the reported effects which could make policy-relevant recommendations from meta-analyses to quickly go out of date. We assessed the extent and patterns of temporal trends in magnitude and statistical significance of the cumulative effects in meta-analyses in applied ecology and conservation published between 2004 and 2018. Of the 121 meta-analyses analysed, 93% showed a temporal trend in cumulative effect magnitude or significance with 27% of the datasets exhibiting temporal trends in both. The most common trend was the early study effect when at least one of the first 5 years effect size estimates exhibited more than 50% magnitude difference to the subsequent estimate. The observed temporal trends persisted in majority of datasets once moderators were accounted for. Only 5 datasets showed significant changes in sample size over time which could potentially explain the observed temporal change in the cumulative effects. Year of publication of meta-analysis had no significant effect on presence of temporal trends in cumulative effects. Our results show that temporal changes in magnitude and statistical significance in applied ecology are widespread and represent a serious potential threat to use of meta-analyses for decision-making in conservation and environmental management. We recommend use of cumulative meta-analyses and call for more studies exploring the causes of the temporal effects.

The association between prenatal cannabis use and congenital birth defects in offspring: A cumulative meta-analysis

OBJECTIVE

To examine the association between prenatal cannabis use and structural birth defects in exposed offspring.

METHODS

In line with the preregistered protocol (PROSPERO: CRD42022368623), we systematically searched PubMed/Medline, CINHAL, EMBASE, Web of Science, ProQuest, Psych-Info, and Google Scholar for published articles until 25 January 2024. The methodological quality of the included studies was appraised by the Newcastle-Ottawa Quality Assessment Scale (NOS). A meta-analysis was carried out to report the pooled effect estimates from the included studies. We further performed subgroup, leave-one-out sensitivity, and meta-regression analyses, which increased the robustness of our findings.

RESULTS

In this cumulative meta-analysis, thirty-six observational studies, consisting of 18 case-control and 18 cohort studies, with 230, 816 cases of birth defects and 18,049,013 controls (healthy babies) were included in the final analysis. We found that offspring exposed to maternal prenatal cannabis are at greater risks of a wide range of structural birth defects: cardiovascular/heart [OR = 2.35: 95 % CI 1.63 - 3.39], gastrointestinal [OR = 2.42: 95 % CI 1.61 - 3.64], central nervous system [OR = 2.87: 95 % CI 1.51 - 5.46], genitourinary [OR = 2.39: 95 % CI 1.11 - 5.17], and any (unclassified) birth defects [OR = 1.25: 95 % CI 1.12 - 1.41].

CONCLUSION

The findings from the current study suggest that maternal prenatal cannabis exposure is associated with a higher risk of different forms of structural birth defects in offspring. The findings underscore the significance of implementing preventive strategies, including enhanced preconception counselling, to address cannabis use during pregnancy and mitigate the risk of birth defects in offspring.

Case fatality rate for Ebola disease, 1976-2022: A meta-analysis of global data

An up-to-date pooled case fatality rate (CFR) for Ebola disease (EBOD) at the global level is lacking. We abstracted EBOD data from 1976 to 2022 for 16 countries and 42 outbreaks to conduct a meta-analysis. The pooled CFR was 60.6% (95% confidence interval (CI) 51.6-69.4; 95% prediction interval 12.9-99.1). Of the four ebolaviruses, Zaire virus was the most lethal (CFR = 66.6%, 95% CI 55.9-76.8), then Sudan virus (CFR=48.5%, 95% CI 38.6-58.4), Bundibugyo virus (CFR=32.8%, 95% CI 25.8-40.2) and Tai Forest virus (CFR= 0%, 95% CI 0.0-97.5). The CFR in sub-Saharan Africa was 61.3% (95% CI 52.8-69.6) and for the rest of the world was 24.5% (95% CI 0.0-67.9%). CFR declined over time but stabilized at 61.0% (95% CI, 52.0-69.0) between 2014 and 2022. Overall, the EBOD CFR is still high and heterogeneous. Accordingly, early diagnosis, early treatment if available, and supportive care are important to prevent significant morbidity and mortality.

The sound and surprise: overlapping meta-analyses on the topic of safety and efficacy of PD-1 and PD-L1 inhibitors in the treatment of non-small cell lung cancer

PURPOSE

To analyze the characteristics of overlapping meta-analyses based on randomized controlled trials (RCTs) which reported PD-1/PD-L1 inhibitors in non-small cell cancer (NSCLC).

METHODS

Meta-analyses were identified from English and Chinese databases until January 1, 2022. Differences in characteristics of overlapping meta-analyses that conducted in China and other countries were compared to assess their publication propensity. The corrected covered area (CCA) and coverage of relevant RCTs were analyzed for subtopics according to detailed intervention types. The waste and redundancy of evidence were assessed in the case of PD-1/PD-L1 inhibitor monotherapy for second-line treatment for NSCLC.

RESULTS

Fifty-nine meta-analyses published in English and 17 meta-analyses published in Chinese reporting 26 RCTs were identified. Fifty-three (69.74%) meta-analyses were conducted in China. The overlapping meta-analyses in China were more likely to be from hospitals, supported by government funding, integrate first and second-line therapies. Five of the six subtopics had overlapping meta-analyses according to specific types of interventions. The CCA of overlapping meta-analyses ranged from 33.33 to 63.19%, and the coverage of relevant RCTs ranged from 63.64 to 100%. All the conclusions of overlapping meta-analyses have been consistent in the subtopic of PD-1/PD-L1 inhibitor monotherapy for second-line treatment since 2017.

CONCLUSION

Overlapping meta-analyses of PD-1/PD-L1 inhibitors in NSCLC hints that meta-analyses under this topic probably exist serious redundancy. Future research should focus on prospective registration of protocols for systematic reviews/meta-analyses, scientific designed PICO, and cumulative meta-analysis to reduce redundant and wasted studies. Journals should strengthen the requirement for reviewing previously published evidence in manuscript review.

The association between vaccine hesitancy and pertussis: a systematic review and meta-analysis

BACKGROUND

Robust routine immunization schedules for pertussis-containing vaccines have been applied for years, but pertussis outbreaks remain a worldwide problem. This study aimed to investigate the association between vaccine hesitancy and pertussis in infants and children.

METHODS

We searched PubMed, Cochrane, Web of Science, Embase, and China National Knowledge Internet for studies published between January 2012 and June 2022. This study included case-control and cohort studies that assessed the association between childhood/maternal vaccine hesitancy and odds ratios (ORs), risk ratios (RRs), and vaccine effectiveness (VE) related to pertussis in infants and children [Formula: see text] 9 years old. ORs/VEs with a 95% confidence interval (CI) were calculated. Random-effects meta-analysis models were used for appropriate pooled estimates, and heterogeneity was assessed using [Formula: see text]. Cumulative meta-analysis and subgroup analyses stratified by study characteristics were performed.

RESULTS

Twenty-two studies were included, with a mean quality score of 7.0 (range 6.0-9.0). Infants and children with pertussis were associated with higher vaccine hesitancy to all doses (OR = 4.12 [95% CI: 3.09-5.50]). The highest OR was between children who were unvaccinated over four doses and children who were fully vaccinated (OR = 14.26 [95%CI: 7.62-26.70]); childhood vaccine delay was not statistically significantly associated with pertussis risk (OR = 1.18 [95% CI: 0.74-1.89]). Maternal vaccine hesitancy was associated with significantly higher pertussis risk in infants aged 2 and 3 months old, with higher pertussis ORs in infants [Formula: see text] 2 months old (OR = 6.02 [95%CI: 4.31-8.50], OR = 5.14 [95%CI: 1.95-13.52] for infants [Formula: see text] 2 and [Formula: see text] 3 months old, respectively). Maternal and childhood VEs were high in reducing pertussis infection in infants and children. The administration time of maternal vaccination had little effect on VE.

CONCLUSION

Vaccine hesitancy increased pertussis risks in infants and children. Ensuring that children receive up-to-date pertussis vaccines is essential; short delays in receiving childhood vaccinations may be unimportant. Maternal vaccinations for pertussis should be encouraged.

Resin Infiltration of Non-Cavitated Proximal Caries Lesions in Primary and Permanent Teeth: A Systematic Review and Scenario Analysis of Randomized Controlled Trials

The present study aimed to meta-analyze and evaluate the certainty of evidence for resin infiltration of proximal carious lesions in primary and permanent teeth. While resin infiltration has been shown efficacious for caries management, the certainty of evidence remains unclear. The protocol was registered with PROSPERO (CRD42018080895), and PRISMA guidelines have been followed. The databases PubMed, Embase, and Cochrane CENTRAL were systematically screened, complemented by hand searches and cross-referencing. Eleven relevant articles were identified and included, i.e., randomized controlled trials (RCTs) comparing the progression of resin infiltrated proximal caries lesions (combined with non-invasive measures) in primary or permanent teeth with non-invasive measures. Random-effects meta-analyses and trial sequential analyses (TSA) were performed for per-protocol (PP), intention-to-treat (ITT), and best/worst case (BC/WC) scenarios. Six included trials assessed lesions in permanent teeth and five trails assessed lesions in primary teeth. The trials had a high or unclear risk of bias. Risk of caries progression was significantly reduced for infiltrated lesions in the PP, ITT, and BC scenarios in both permanent teeth and primary teeth, but not in the WC scenario. According to the TSA, firm evidence was reached for all of the scenarios except the WC. In conclusion, there is firm evidence for resin infiltration arresting proximal caries lesions in permanent and primary teeth.

Transcutaneous electrical acupoint stimulation for pregnancy outcomes in women undergoing in vitro fertilization-embryo transfer: A systematic review and meta-analysis

BACKGROUND

Infertility is a common health problem affecting couples of childbearing age. The proposal of in vitro fertilization-embryo transfer (IVF-ET) solves the problem of infertility to a certain extent. However, the average success rate of IVF-ET is still low. Some studies conclude that transcutaneous electrical acupoint stimulation (TEAS) could improve pregnancy outcomes in women undergoing IVF-ET, however, there is a lack of comprehensive synthesis and evaluation of existing evidence.

OBJECTIVE

To conduct a systematic review and meta-analysis to assess whether TEAS is effective and safe to improve the pregnancy outcomes for women undergoing IVF-ET.

METHODS

Eight online databases were searched from inception to 19 November 2021. In addition, four clinical trial registries were also searched, relevant references were screened, and experts were consulted for possible eligible studies. Randomized controlled trials (RCTs) that included patients with infertility who underwent IVF and used TEAS as the main adjuvant treatment vs. non-TEAS or mock intervention controls were included. The clinical pregnancy rate (CPR) was considered the primary outcome. High-quality embryo rate (HQER), live birth rate (LBR), biochemical pregnancy rate (BPR), ongoing pregnancy rate (OPR), early miscarriage rate (EMR), birth defects rate (BDR), and adverse events related to interventions were regarded as secondary outcomes. The selection, data extraction, risk of bias assessment, and data synthesis were conducted by two independent researchers using Endnote software V.9.1 and Stata 16.0 software. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was used to evaluate the evidence quality of each outcome.

RESULTS

There were 19 RCTs involving 5,330 participants included. The results of meta-analyses showed that TEAS can improve CPR [RR = 1.42, 95% CI (1.31, 1.54)], HQER [RR = 1.09, 95% CI (1.05, 1.14)], and BPR [RR = 1.45, 95% CI (1.22, 1.71)] of women underwent IVF-ET with low quality of evidence, and improve LBR [RR = 1.42, 95% CI (1.19, 1.69)] with moderate quality of evidence. There was no significant difference in EMR [RR = 1.08, 95% CI (0.80, 1.45)] and BDR [RR = 0.93, 95% CI (0.13, 6.54)] with very low and moderate quality of evidence, respectively. A cumulative meta-analysis showed that the effective value of TEAS vs. controls was relatively stable in 2018 [RR = 1.52, 95% CI (1.35, 1.71)]. In addition, no serious adverse events associated with TEAS were reported.

CONCLUSION

Our findings suggest that TEAS may be an effective and safe adjuvant treatment for women undergoing IVF-ET to improve pregnancy outcomes. However, the current evidence quality is considered to be limited, and more high-quality RCTs are needed for further verification in the future.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/PROSPERO/display_record.php?ID=CRD42021238871, identifier: CRD42021238871.