Comparison of evidence of treatment effects in randomized and nonrandomized studies

Impact of neoadjuvant chemotherapy on short-term outcomes after simple and complex minimally invasive minor hepatectomy for colorectal liver metastases: A propensity-score matched and coarsened exact matched study

BACKGROUND

In the last three decades, minimally invasive liver resection has been replacing conventional open approach in liver surgery. More recently, developments in neoadjuvant chemotherapy have led to increased multidisciplinary management of colorectal liver metastases with both medical and surgical treatment modalities. However, the impact of neoadjuvant chemotherapy on the surgical outcomes of minimally invasive liver resections remains poorly understood.

METHODS

A multicenter, international, database of 4998 minimally invasive minor hepatectomy for colorectal liver metastases was used to compare surgical outcomes in patients who received neoadjuvant chemotherapy with surgery alone. To correct for baseline imbalance, propensity score matching, coarsened exact matching and inverse probability treatment weighting were performed.

RESULTS

2546 patients met the inclusion criteria. After propensity score matching there were 759 patients in both groups and 383 patients in both groups after coarsened exact matching. Baseline characteristics were equal after both matching strategies. Neoadjuvant chemotherapy was not associated with statistically significant worse surgical outcomes of minimally invasive minor hepatectomy.

CONCLUSION

Neoadjuvant chemotherapy had no statistically significant impact on short-term surgical outcomes after simple and complex minimally invasive minor hepatectomy for colorectal liver metastases.

Natural Experiments as a Study Method in Spinal Trauma Surgery: A Systematic Review

STUDY DESIGN

Systematic review.

OBJECTIVES

To determine if the natural experiment design is a useful research methodology concept in spinal trauma care, and to determine if this methodology can be a viable alternative when randomized controlled trials are either infeasible or unethical.

METHODS

A Medline, Embase and Cochrane database search was performed between 2004 and 2023 for studies comparing different treatment modalities of spinal trauma. All observational studies with a natural experiment design comparing different treatment modalities of spinal trauma were included. Data extraction and quality assessment with the MINORS criteria was performed.

RESULTS

Four studies with a natural experiment design regarding patients with traumatic spinal fractures were included. All studies were retrospective, one study collected follow-up data prospectively. Three studies compared different operative treatment modalities, whereas one study compared different antibiotic treatment strategies. Two studies compared preferred treatment modalities between expertise centers, one study between departments (neuro- and orthopedic surgery) and one amongst surgeons. For the included retrospective studies, MINORS scores (maximum score 18) were high ranging from 12-17 and with a mean (SD) of 14.6 (1.63).

CONCLUSIONS

Since 2004 only four studies using a natural experiment design have been conducted in spinal trauma. In the included studies, comparability of patient groups was high emphasizing the potential of natural experiments in spinal trauma research. Natural experiments design should be considered more frequently in future research in spinal trauma as they may help to address difficult clinical problems when RCT's are infeasible or unethical.

Identifying the mediating role of inflammation on the relationship between socioeconomic status and Alzheimer's disease: a Mendelian randomization analysis and mediation analysis

BACKGROUND AND OBJECTIVES

Observational studies have demonstrated a significant association between socio-economic status (SES) and Alzheimer's disease (AD). Nonetheless, the precise biological mechanisms underlying this association remain unclear. Therefore, we adopted a Mendelian Randomization (MR) approach to investigate the causal relationship between SES and genetic susceptibility to AD, as well as to explore the potential mediation effects of inflammation.

METHODS

Large-scale cohorts based on publicly available genome-wide association study (GWAS) datasets from European populations were employed for conducting the MR study. The primary criterion utilized was the inverse-variance weighting (IVW) model. Heterogeneity and horizontal pleiotropy were assessed. In addition, multivariate MR (MVMR) was utilized to correct the confounders. Moreover, a two-step MR approach was used to evaluate the potential mediating effects of factors on the causal effects between SES and AD.

RESULTS

As indicated by the results of the IVW model, educational years (OR = 0.708, 95% CI 0.610-0.821, P < 0.001) and household income (OR = 0.746, 95% CI 0.566-0.982, P = 0.037) was associated with a decreased genetic susceptibility risk for AD. The univariable results showed that the causal effect of educational years on the lower risk of AD remained significant (OR = 0.643, 95% CI 0.467-0.886, P = 0.006). In addition, our findings indicated that C-reactive protein (CRP) played a role in the causal effect of educational years on AD. The proportions of mediation were - 50.08% (95% CI - 92.78; - 7.38%).

DISCUSSION

These findings provided evidence supporting the causal effect of educational attainment lower AD risk, with inflammation playing a mediating role. These findings may inform prevention strategies and interventions directed toward AD. Future studies should explore other plausible biological mechanisms.

Is cost of surgery and hospital length of stay increased for sickle cell disease patients undergoing total joint replacement surgeries? Systematic review and multivariate meta-analysis

Background

Sickle cell disease (SCD) patients undergo major joint replacement surgeries with significant improvement in quality of life. Previous literature have tried to explore differences in hospital charges and length of stay between patients with and without SCD. The aim of this meta-analysis is to find out if both outcomes are increased for patients with SCD patients compared to those without SCD.

Methods

Literature search was conducted and studies that compared hospital charges and length of stay between patients with and without sickle cell disease following major arthroplasties were retrieved. A multivariate meta-analysis was conducted using Random-Effect model with the Restricted Maximum Likelihood (REML) using the Metafor Package in R and Rstudio.

Results

Four observational studies were found eligible for the study. The estimated average mean difference based on the random effect model for hospital charges was 7548.50 (95 % CI: 3779.65 to 11317.65) and for length of stay was 2.28 (95 % CI: 1.32 to 3.24) while the prediction interval for the true mean difference for both outcomes were -1810.56 to 16907.56 and -0.01 to 4.57 respectively.

Conclusion

This present study showed that hospital charges and length of stay are increased for patients with SCD compared to patients without.

Generating and using real-world data: A worthwhile uphill battle

The precision oncology paradigm challenges the feasibility and data generalizability of traditional clinical trials. Consequently, an unmet need exists for practical approaches to test many subgroups, evaluate real-world drug value, and gather comprehensive, accessible datasets to validate novel biomarkers. Real-world data (RWD) are increasingly recognized to have the potential to fill this gap in research methodology. Established applications of RWD include informing disease epidemiology, pharmacovigilance, and healthcare quality assessment. Currently, concerns regarding RWD quality and comprehensiveness, privacy, and biases hamper their broader application. Nonetheless, RWD may play a pivotal role in supplementing clinical trials, enabling conditional reimbursement and accelerated drug access, and innovating trial conduct. Moreover, purpose-built RWD repositories may support the extension or refinement of drug indications and facilitate the discovery and validation of new biomarkers. This perspective explores the potential of leveraging RWD to advance oncology, highlights its benefits and challenges, and suggests a path forward in this evolving field.

Non-linear association of baseline viral load with on-treatment hepatocellular carcinoma risk in chronic hepatitis B

OBJECTIVE

The association between baseline pretreatment serum HBV DNA levels and on-treatment hepatocellular carcinoma (HCC) risk remains controversial in patients with chronic hepatitis B (CHB). We aimed to investigate the association between baseline HBV viral load and on-treatment HCC risk in CHB patients without cirrhosis.

DESIGN

Using a multicentre historical cohort study including 4693 hepatitis B e antigen (HBeAg)-negative and HBeAg-positive, adult CHB patients without cirrhosis who initiated antiviral treatment, HCC risk was estimated by baseline HBV viral load as a categorical variable.

RESULTS

During a median of 7.6 years of antiviral treatment, 193 patients developed HCC (0.53 per 100 person- years). Baseline HBV DNA level was independently associated with on-treatment HCC risk in a non-linear, parabolic pattern. Patients with moderate baseline viral loads (5.00-7.99 log10 IU/mL) exhibited the highest HCC risk (HR, 2.60; p<0.001), followed by those with low viral loads (3.30-4.99 log10 IU/mL; HR, 1.66; p=0.11). Patients with high viral loads (≥8.00 log10 IU/mL) presented the lowest HCC risk. Particularly, patients with baseline HBV DNA levels 6.00-6.99 log10 IU/mL had the highest on-treatment HCC risk (HR, 3.36; p<0.001) compared with those with baseline HBV DNA levels≥8.00 log10 IU/mL. These findings were more prominent among HBeAg-positive patients, younger patients, or those with less advanced hepatic fibrosis.

CONCLUSION

Patients with moderate baseline viral load, particularly around 6 log10 IU/mL, demonstrated the highest on-treatment HCC risk, despite long-term antiviral treatment. Early initiation of antiviral treatment, tailored to viral load, should be considered to minimise HCC risk in adult CHB patients without cirrhosis.

Celebrating the Data from 100,000 Real-World Users of the MiniMed™ 780G System in Europe, Middle East, and Africa Collected Over 3 Years: From Data to Clinical Evidence

Introduction: The present report celebrates the benchmarking of 100,000 MiniMed™ 780G system users in Europe, Middle East, and Africa (EMEA) and summarizes the major insights into the usability and outcomes of this system. Methods: Carelink Personal data (August 2020-August 2023) of users living in EMEA were analyzed. Continuous glucose monitoring-based endpoints were aggregated for (1) the full cohort and (2) a 12-month longitudinal cohort. Subanalyses were done for users on optimal settings (those spending ≥95% of time with glucose target of 100 mg/dL, and ≥95% of time with active insulin time of 2 h), for self-reported age groups (≤15 and ≥56 years) and for various countries/regions. Results: Data from 101,629 users (34 countries) were analyzed. Mean time in range (TIR) was 72.3%, glucose management indicator (GMI) was 7%, time below 70 mg/dL (TBR70) was 2.0% and time below 54 mg/dL (TBR54) was 0.4%. In terms of international targets, 59.6% of users achieved a GMI <7%, 62.5% a TIR >70%, 88.4% a TBR70 < 4%, and 90.0% a TBR54 < 1%. Data improved impressively in optimal setting users (TIR = 78.8%, and users reaching TIR >70% = 86.3%) while safety remained (TBR70 = 2.2% and TBR54 = 0.4%). Data showed consistency across self-reported age groups and geographies. In the longitudinal cohort, TIR reached 75.5% in the first month and remained 73.3% or higher over the 12-month period. Conclusion: Over 100,000 users of the MiniMed™ 780G system have demonstrated consistency in achieving target control of glycemia.

Nirmatrelvir/ritonavir for COVID-19: an overview of systematic reviews

OBJECTIVES

A reappraisal of the validity of the conclusions of systematic reviews (SRs) related to nirmatrelvir/ritonavir for the treatment of COVID-19.

METHODS

An overview of SRs (umbrella review). The methodological quality of the SRs was assessed using the AMSTAR 2 checklist; quality of the evidence from the trials included in each SR was appraised following the GRADE approach.

RESULTS

Sixteen SRs with meta-analysis published between 2020 and 2023 were included in this overview. The SRs reported data from 108 overlapping reports, based on 43 individual primary studies [3 randomized clinical trials (RCTs), 40 non-RCTs]. In outpatient settings the use of nirmatrelvir/ritonavir reduced overall mortality, hospital admission and progression of disease compared with controls (from moderate to low certainty of evidence); nirmatrelvir/ritonavir reduced mortality, hospital admission and progression of disease in both immunized and non-immunized patients. No differences in the occurrence of any adverse events between groups were observed in the large majority of SRs; serious adverse events, including adverse events requiring discontinuation of treatment, were reported with lower prevalence in nirmatrelvir recipients compared with controls (from low to moderate certainty of evidence).

CONCLUSIONS

There is low to moderate certainty of evidence from SRs that nirmatrelvir/ritonavir reduces mortality, clinical progression and hospitalization rate in COVID-19 patients compared with controls, without increasing the occurrence of overall and serious adverse events. Based on the overall methodological assessment, on average we can have high confidence in the quality of results generated by the SRs.

Association between vitamin B12 deficiency and risk of Paediatric narcolepsy: Evidence from cross-sectional study and Mendelian randomization analysis

BACKGROUND

Narcolepsy, a chronic neurologic sleep disorder, has sparked growing interest in the potential role of vitamin B12 in its pathogenic mechanism. However, research on this association has predominantly focused on adults. Our objective was to delineate the phenotypic and genetic connections between serum vitamin B12 levels and paediatric narcolepsy.

METHODS

To investigate the causal relationship between vitamin B12 and paediatric narcolepsy, we conducted a retrospective analysis involving 60 narcolepsy patients and a matched control group. Univariate and multivariate logistic regression models were employed to identify independent factors influencing paediatric narcolepsy. Furthermore, a bidirectional two-sample Mendelian randomization (MR) analysis was performed to assess the causal connection between serum vitamin B12 levels and narcolepsy.

RESULTS

Paediatric narcolepsy patients showed significantly lower serum levels of vitamin B12 and folate compared to the control group (P < 0.05). Multivariate logistic regression analysis identified serum vitamin B12 as the exclusive independent factor influencing paediatric narcolepsy (P < 0.001; OR = 0.96; 95%CI: 0.94-0.98). Additionally, IVW model results provided compelling evidence supporting a potential causal association between serum vitamin B12 levels and paediatric narcolepsy (OR: 0.958, 95% CI = 0.946-0.969, P = 0.001).

CONCLUSION

This study establishes connections at both phenotypic and genetic levels, associating vitamin B12 deficiency with an increased risk of paediatric narcolepsy. These findings provide innovative perspectives for clinical strategies in the prevention and treatment of narcolepsy.

Synthesis methods used to combine observational studies and randomised trials in published meta-analyses

BACKGROUND

This study examined the synthesis methods used in meta-analyses pooling data from observational studies (OSs) and randomised controlled trials (RCTs) from various medical disciplines.

METHODS

We searched Medline via PubMed to identify reports of systematic reviews of interventions, including and pooling data from RCTs and OSs published in 110 high-impact factor general and specialised journals between 2015 and 2019. Screening and data extraction were performed in duplicate. To describe the synthesis methods used in the meta-analyses, we considered the first meta-analysis presented in each article.

RESULTS

Overall, 132 reports were identified with a median number of included studies of 14 [9-26]. The median number of OSs was 6.5 [3-12] and that of RCTs was 3 [1-6]. The effect estimates recorded from OSs (i.e., adjusted or unadjusted) were not specified in 82% (n = 108) of the meta-analyses. An inverse-variance common-effect model was used in 2% (n = 3) of the meta-analyses, a random-effects model was used in 55% (n = 73), and both models were used in 40% (n = 53). A Poisson regression model was used in 1 meta-analysis, and 2 meta-analyses did not report the model they used. The mean total weight of OSs in the studied meta-analyses was 57.3% (standard deviation, ± 30.3%). Only 44 (33%) meta-analyses reported results stratified by study design. Of them, the results between OSs and RCTs had a consistent direction of effect in 70% (n = 31). Study design was explored as a potential source of heterogeneity in 79% of the meta-analyses, and confounding factors were investigated in only 10% (n = 13). Publication bias was assessed in 70% (n = 92) of the meta-analyses. Tau-square was reported in 32 meta-analyses with a median of 0.07 [0-0.30].

CONCLUSION

The inclusion of OSs in a meta-analysis on interventions could provide useful information. However, considerations of several methodological and conceptual aspects of OSs, that are required to avoid misleading findings, were often absent or insufficiently reported in our sample.

Causal relationships between delirium and Parkinson's disease: a bidirectional two-sample Mendelian randomization study

BACKGROUND

Previous observational studies have suggested a notably elevated prevalence of delirium in individuals diagnosed with Parkinson's disease (PD), thereby implying a potential increased susceptibility to delirium among PD patients. However, it is imperative to acknowledge that observational studies inherently possess limitations, rendering it arduous to establish a definitive causal or reverse causal association between delirium and PD.

METHODS

To explore the relationship between delirium and PD, a bidirectional two-sample Mendelian randomization (MR) was conducted using summary statistics obtained from genome-wide association studies. The main analysis was performed using the inverse-variance weighted (IVW) method, with further analyses conducted using MR Egger, weighted median, and weighted mode to ensure accuracy of findings. Additionally, Cochran's Q statistics and MR Egger intercept were utilized to assess heterogeneity and horizontal pleiotropy, respectively.

RESULTS

According to the results obtained from the IVW model, no compelling evidence was found to support a potential causal association between delirium and PD (IVW: odds ratio [OR]: 0.996, 95% confidence interval CI 0.949-1.043, P = 0.845). Additionally, in the reverse direction, based on the results obtained from the IVW model, no significant evidence was found to support a causal association between PD and delirium (IVW: OR: 1.078, 95%CI  0.960-1.204, P = 0.225). A sensitivity analysis verified the reliability of the results.

CONCLUSION

According to the MR findings, a bidirectional causal relationship between delirium and PD is not observed. It is crucial to conduct further research in clinical practice to investigate the association between delirium and the risk of PD.

Patient values in patient-provider communication about participation in early phase clinical cancer trials: a qualitative analysis before and after implementation of an online value clarification tool intervention

BACKGROUND

Patients with advanced cancer who no longer have standard treatment options available may decide to participate in early phase clinical trials (i.e. experimental treatments with uncertain outcomes). Shared decision-making (SDM) models help to understand considerations that influence patients' decision. Discussion of patient values is essential to SDM, but such communication is often limited in this context and may require new interventions. The OnVaCT intervention, consisting of a preparatory online value clarification tool (OnVaCT) for patients and communication training for oncologists, was previously developed to support SDM. This study aimed to qualitatively explore associations between patient values that are discussed between patients and oncologists during consultations about potential participation in early phase clinical trials before and after implementation of the OnVaCT intervention.

METHODS

This study is part of a prospective multicentre nonrandomized controlled clinical trial and had a between-subjects design: pre-intervention patients received usual care, while post-intervention patients additionally received the OnVaCT. Oncologists participated in the communication training between study phases. Patients' initial consultation on potential early phase clinical trial participation was recorded and transcribed verbatim. Applying a directed approach, two independent coders analysed the transcripts using an initial codebook based on previous studies. Steps of continuous evaluation and revision were repeated until data saturation was reached.

RESULTS

Data saturation was reached after 32 patient-oncologist consultations (i.e. 17 pre-intervention and 15 post-intervention). The analysis revealed the values: hope, perseverance, quality or quantity of life, risk tolerance, trust in the healthcare system/professionals, autonomy, social adherence, altruism, corporeality, acceptance of one's fate, and humanity. Patients in the pre-intervention phase tended to express values briefly and spontaneously. Oncologists acknowledged the importance of patients' values, but generally only gave 'contrasting' examples of why some accept and others refuse to participate in trials. In the post-intervention phase, many oncologists referred to the OnVaCT and/or asked follow-up questions, while patients used longer phrases that combined multiple values, sometimes clearly indicating their weighing.

CONCLUSIONS

While all values were recognized in both study phases, our results have highlighted the different communication patterns around patient values in SDM for potential early phase clinical trial participation before and after implementation of the OnVaCT intervention. This study therefore provides a first (qualitative) indication that the OnVaCT intervention may support patients and oncologists in discussing their values.

TRIAL REGISTRATION

Netherlands Trial Registry: NL7335, registered on July 17, 2018.

Visualizing the target estimand in comparative effectiveness studies with multiple treatments

Aim: Comparative effectiveness research using real-world data often involves pairwise propensity score matching to adjust for confounding bias. We show that corresponding treatment effect estimates may have limited external validity, and propose two visualization tools to clarify the target estimand. Materials & methods: We conduct a simulation study to demonstrate, with bivariate ellipses and joy plots, that differences in covariate distributions across treatment groups may affect the external validity of treatment effect estimates. We showcase how these visualization tools can facilitate the interpretation of target estimands in a case study comparing the effectiveness of teriflunomide (TERI), dimethyl fumarate (DMF) and natalizumab (NAT) on manual dexterity in patients with multiple sclerosis. Results: In the simulation study, estimates of the treatment effect greatly differed depending on the target population. For example, when comparing treatment B with C, the estimated treatment effect (and respective standard error) varied from -0.27 (0.03) to -0.37 (0.04) in the type of patients initially receiving treatment B and C, respectively. Visualization of the matched samples revealed that covariate distributions vary for each comparison and cannot be used to target one common treatment effect for the three treatment comparisons. In the case study, the bivariate distribution of age and disease duration varied across the population of patients receiving TERI, DMF or NAT. Although results suggest that DMF and NAT improve manual dexterity at 1 year compared with TERI, the effectiveness of DMF versus NAT differs depending on which target estimand is used. Conclusion: Visualization tools may help to clarify the target population in comparative effectiveness studies and resolve ambiguity about the interpretation of estimated treatment effects.

Mechanical circulatory support for cardiogenic shock: a network meta-analysis of randomized controlled trials and propensity score-matched studies

PURPOSE

Cardiogenic shock is associated with high mortality. In refractory shock, it is unclear if mechanical circulatory support (MCS) devices improve survival. We conducted a network meta-analysis to determine which MCS devices confers greatest benefit.

METHODS

We searched MEDLINE, Embase, and Scopus databases through 27 August 2023 for relevant randomized controlled trials (RCTs) and propensity score-matched studies (PSMs). We conducted frequentist network meta-analysis, investigating mortality (either 30 days or in-hospital) as the primary outcome. We assessed risk of bias (Cochrane risk of bias 2.0 tool/Newcastle-Ottawa Scale) and as sensitivity analysis reconstructed survival data from published survival curves for a one-stage unadjusted individual patient data (IPD) meta-analysis using a stratified Cox model.

RESULTS

We included 38 studies (48,749 patients), mostly reporting on patients with Society for Cardiovascular Angiography and Intervention shock stages C-E cardiogenic shock. Compared with no MCS, extracorporeal membrane oxygenation with intra-aortic balloon pump (ECMO-IABP; network odds ratio [OR]: 0.54, 95% confidence interval (CI): 0.33-0.86, moderate certainty) was associated with lower mortality. There were no differences in mortality between ECMO, IABP, microaxial ventricular assist device (mVAD), ECMO-mVAD, centrifugal VAD, or mVAD-IABP and no MCS (all very low certainty). Our one-stage IPD survival meta-analysis based on the stratified Cox model found only ECMO-IABP was associated with lower mortality (hazard ratio, HR, 0.55, 95% CI 0.46-0.66).

CONCLUSION

In patients with cardiogenic shock, ECMO-IABP may reduce mortality, while other MCS devices did not reduce mortality. However, this must be interpreted within the context of inter-study heterogeneity and limited certainty of evidence.

Causal relationships between type 1 diabetes mellitus and Alzheimer's disease and Parkinson's disease: a bidirectional two-sample Mendelian randomization study

BACKGROUND

Previous compelling evidence suggests an association between Type 2 diabetes (T2D) and neurodegenerative diseases. However, it remains uncertain whether Type 1 diabetes mellitus (T1DM) exerts a causal influence on the risk of Alzheimer's disease (AD) and Parkinson's disease (PD). Consequently, this study employed a bidirectional two-sample Mendelian Randomization (MR) approach to investigate the causal relationship between T1DM and the genetic susceptibility to AD and PD.

METHODS

We utilized large-scale cohorts derived from publicly available genome-wide association study datasets involving European populations to perform MR analyses. The primary analytical method employed was the inverse-variance weighted (IVW) approach. Furthermore, sensitivity analyses, including assessments of heterogeneity and horizontal pleiotropy, were carried out using Cochran's Q, MR-Egger intercept, and MR-PRESSO tests to enhance the robustness of our conclusions.

RESULTS

Using the IVW-based method, the MR analysis indicated no significant association between genetically determined T1DM and AD (OR = 0.984, 95% CI: 0.958-1.011, p = 0.247). Conversely, T1DM appeared to be associated with a reduced risk of genetic susceptibility to PD (IVW: OR = 0.958, 95% CI: 0.928-0.989, p = 0.001). In the reverse direction, no evidence of reverse causality was observed between AD (OR = 1.010, 95% CI: 0.911-1.116, p = 0.881) or PD (OR = 1.164, 95% CI: 0.686-2.025, p = 0.5202) and T1DM. Additionally, our analysis found no indications of the results being influenced by horizontal pleiotropy.

CONCLUSION

This MR study reveals that T1DM is associated with a reduced genetic susceptibility to PD, whereas no significant genetic susceptibility is observed between T1DM and AD. These findings suggest that T1DM may have a distinct role in the development of neurodegenerative diseases compared to T2D. Further investigations are warranted to elucidate the underlying mechanisms and provide a more comprehensive understanding of this relationship.

Healthcare outcomes assessed with observational study designs compared with those assessed in randomized trials: a meta-epidemiological study

BACKGROUND

Researchers and decision-makers often use evidence from randomised controlled trials (RCTs) to determine the efficacy or effectiveness of a treatment or intervention. Studies with observational designs are often used to measure the effectiveness of an intervention in 'real world' scenarios. Numerous study designs and their modifications (including both randomised and observational designs) are used for comparative effectiveness research in an attempt to give an unbiased estimate of whether one treatment is more effective or safer than another for a particular population. An up-to-date systematic analysis is needed to identify differences in effect estimates from RCTs and observational studies. This updated review summarises the results of methodological reviews that compared the effect estimates of observational studies with RCTs from evidence syntheses that addressed the same health research question.

OBJECTIVES

To assess and compare synthesised effect estimates by study type, contrasting RCTs with observational studies. To explore factors that might explain differences in synthesised effect estimates from RCTs versus observational studies (e.g. heterogeneity, type of observational study design, type of intervention, and use of propensity score adjustment). To identify gaps in the existing research comparing effect estimates across different study types.

SEARCH METHODS

We searched MEDLINE, the Cochrane Database of Systematic Reviews, Web of Science databases, and Epistemonikos to May 2022. We checked references, conducted citation searches, and contacted review authors to identify additional reviews.

SELECTION CRITERIA

We included systematic methodological reviews that compared quantitative effect estimates measuring the efficacy or effectiveness of interventions tested in RCTs versus in observational studies. The included reviews compared RCTs to observational studies (including retrospective and prospective cohort, case-control and cross-sectional designs). Reviews were not eligible if they compared RCTs with studies that had used some form of concurrent allocation.

DATA COLLECTION AND ANALYSIS

Using results from observational studies as the reference group, we examined the relative summary effect estimates (risk ratios (RRs), odds ratios (ORs), hazard ratios (HRs), mean differences (MDs), and standardised mean differences (SMDs)) to evaluate whether there was a relatively larger or smaller effect in the ratio of odds ratios (ROR) or ratio of risk ratios (RRR), ratio of hazard ratios (RHR), and difference in (standardised) mean differences (D(S)MD). If an included review did not provide an estimate comparing results from RCTs with observational studies, we generated one by pooling the estimates for observational studies and RCTs, respectively. Across all reviews, we synthesised these ratios to produce a pooled ratio of ratios comparing effect estimates from RCTs with those from observational studies. In overviews of reviews, we estimated the ROR or RRR for each overview using observational studies as the reference category. We appraised the risk of bias in the included reviews (using nine criteria in total). To receive an overall low risk of bias rating, an included review needed: explicit criteria for study selection, a complete sample of studies, and to have controlled for study methodological differences and study heterogeneity. We assessed reviews/overviews not meeting these four criteria as having an overall high risk of bias. We assessed the certainty of the evidence, consisting of multiple evidence syntheses, with the GRADE approach.

MAIN RESULTS

We included 39 systematic reviews and eight overviews of reviews, for a total of 47. Thirty-four of these contributed data to our primary analysis. Based on the available data, we found that the reviews/overviews included 2869 RCTs involving 3,882,115 participants, and 3924 observational studies with 19,499,970 participants. We rated 11 reviews/overviews as having an overall low risk of bias, and 36 as having an unclear or high risk of bias. Our main concerns with the included reviews/overviews were that some did not assess the quality of their included studies, and some failed to account appropriately for differences between study designs - for example, they conducted aggregate analyses of all observational studies rather than separate analyses of cohort and case-control studies. When pooling RORs and RRRs, the ratio of ratios indicated no difference or a very small difference between the effect estimates from RCTs versus from observational studies (ratio of ratios 1.08, 95% confidence interval (CI) 1.01 to 1.15). We rated the certainty of the evidence as low. Twenty-three of 34 reviews reported effect estimates of RCTs and observational studies that were on average in agreement. In a number of subgroup analyses, small differences in the effect estimates were detected: - pharmaceutical interventions only (ratio of ratios 1.12, 95% CI 1.04 to 1.21); - RCTs and observational studies with substantial or high heterogeneity; that is, I2 ≥ 50% (ratio of ratios 1.11, 95% CI 1.04 to 1.18); - no use (ratio of ratios 1.07, 95% CI 1.03 to 1.11) or unclear use (ratio of ratios 1.13, 95% CI 1.03 to 1.25) of propensity score adjustment in observational studies; and - observational studies without further specification of the study design (ratio of ratios 1.06, 95% CI 0.96 to 1.18). We detected no clear difference in other subgroup analyses.

AUTHORS' CONCLUSIONS

We found no difference or a very small difference between effect estimates from RCTs and observational studies. These findings are largely consistent with findings from recently published research. Factors other than study design need to be considered when exploring reasons for a lack of agreement between results of RCTs and observational studies, such as differences in the population, intervention, comparator, and outcomes investigated in the respective studies. Our results underscore that it is important for review authors to consider not only study design, but the level of heterogeneity in meta-analyses of RCTs or observational studies. A better understanding is needed of how these factors might yield estimates reflective of true effectiveness.

Local Tumour Control Following Microwave Ablation: Protocol for the Prospective Observational CIEMAR Study

PURPOSE

Microwave ablation (MWA) is a treatment modality for colorectal liver metastases (CRLM). While potentially curative, more information is needed on factors that contribute to long-term local tumour control. The prospective multicentre observational study CIRSE Emprint Microwave Ablation Registry aims to prospectively collect real-world technical data and clinical outcomes on patients treated with MWA in CRLM.

METHODS

Eligible patients are adults with up to 9 local treatment naïve CRLM of ≤ 3 cm completely treatable with either MWA alone or MWA with resection and/or radiotherapy within 8 weeks. Data are collected, at baseline, every 3 months until 12 months, and thereafter every 6 months until the end of the study. The primary outcome measure is local tumour control. Secondary outcome measures are overall survival, (hepatic-) disease-free survival, time-to-progression untreatable by ablation, systemic therapy vacation, safety, and quality of life. Covariates related to the primary outcome measure will be assessed using a stratified log-rank test and an univariable Cox proportional hazard regression. A sample size of 500 patients with 750 lesions produces a two-sided 95% confidence interval with a precision equal to 0.057.

RESULTS

Between September 2019 and December 2022, 500 patients have been enrolled with at least 976 treated tumours.

CONCLUSION

The prospective observational CIEMAR study will provide valuable insights into the real-world use of MWA, helping in the future patient selection and clarifying factors that may contribute to long-term local tumour control.

TRIAL REGISTRATION

NCT03775980.

A Systematic Review Informing the Management of Symptomatic Brain Radiation Necrosis After Stereotactic Radiosurgery and International Stereotactic Radiosurgery Society Recommendations

Radiation necrosis (RN) secondary to stereotactic radiosurgery is a significant cause of morbidity. The optimal management of corticosteroid-refractory brain RN remains unclear. Our objective was to summarize the literature specific to efficacy and toxicity of treatment paradigms for patients with symptomatic corticosteroid-refractory RN and to provide consensus guidelines for grading and management of RN on behalf of the International Stereotactic Radiosurgery Society. A systematic review of articles pertaining to treatment of RN with bevacizumab, laser interstitial thermal therapy (LITT), surgical resection, or hyperbaric oxygen therapy was performed. The primary composite outcome was clinical and/or radiologic stability/improvement (ie, proportion of patients achieving improvement or stability with the given intervention). Proportions of patients achieving the primary outcome were pooled using random weighted-effects analysis but not directly compared between interventions. Twenty-one articles were included, of which only 2 were prospective studies. Thirteen reports were relevant for bevacizumab, 5 for LITT, 5 for surgical resection and 1 for hyperbaric oxygen therapy. Weighted effects analysis revealed that bevacizumab had a pooled symptom improvement/stability rate of 86% (95% CI 77%-92%), pooled T2 imaging improvement/stability rate of 93% (95% CI 87%-98%), and pooled T1 postcontrast improvement/stability rate of 94% (95% CI 87%-98%). Subgroup analysis showed a statistically significant improvement favoring treatment with low-dose (below median, ≤7.5 mg/kg every 3 weeks) versus high-dose bevacizumab with regards to symptom improvement/stability rate (P = .02) but not for radiologic T1 or T2 changes. The pooled T1 postcontrast improvement/stability rate for LITT was 88% (95% CI 82%-93%), and pooled symptom improvement/stability rate for surgery was 89% (95% CI 81%-96%). Toxicity was inconsistently reported but was generally low for all treatment paradigms. Corticosteroid-refractory RN that does not require urgent surgical intervention, with sufficient noninvasive diagnostic testing that favors RN, can be treated medically with bevacizumab in carefully selected patients as a strong recommendation. The role of LITT is evolving as a less invasive image guided surgical modality; however, the overall evidence for each modality is of low quality. Prospective head-to-head comparisons are needed to evaluate the relative efficacy and toxicity profile among treatment approaches.

The role of randomized controlled trials, registries, observational databases in evaluating new interventions

Approaches to comparing safety and efficacy of interventions include analyzing data from randomized controlled trials (RCTs), registries and observational databases (ODBs). RCTs are regarded as the gold standard but data from such trials are sometimes unavailable because a disease is uncommon, because the intervention is uncommon, because of structural limitations or because randomization cannot be done for practical or (seemingly) ethical reasons. There are many examples of an unproved intervention being so widely-believed to be effective that clinical trialists and potential subjects decline randomization. Often, when a RCT is finally done the intervention is proved ineffective or even harmful. These situations are termed medical reversals and are not uncommon [1,2]. There is also the dilemma of when seemingly similar RCTs report discordant conclisions Data from high-quality registries, especially ODBs can be used when data from RCTs are unavailable but also have limitations. Biases and confounding co-variates may be unknown, difficult or impossible to identify and/or difficult to adjust for adequately. However, ODBs sometimes have large numbers of diverse subjects and often give answers more useful to clinicians than RCTs. Side-by-side comparisons suggest analyses from high-quality ODBs often give similar conclusions from high quality RCTs. Meta-analyses combining data from RCTs, registries and ODBs are sometimes appropriate. We suggest increased use of registries and ODBs to compare efficacy of interventions.

Long-Term Outcomes of Open Versus Endovascular Treatment for Abdominal Aortic Aneurysm: Systematic Review and Meta-Analysis With Reconstructed Time-to-Event Data

BACKGROUND

The advent of endovascular techniques has revolutionized the care of patients with uncomplicated abdominal aortic aneurysms. This analysis compares the overall survival and the freedom from reintervention rate between open surgical repair (OSR) and endovascular repair (EVAR) in patients undergoing elective abdominal aortic aneurysm (AAA) repair.

METHODS

PubMed, Scopus, and Cochrane databases were searched for studies including patients who underwent either OSR or EVAR for uncomplicated AAA. All randomized controlled trials and propensity-score-matched cohort studies reporting on the outcomes of interest were considered eligible for inclusion. The systematic search of the literature was performed by 2 independent investigators in accordance with the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. We conducted 1-stage and 2-stage meta-analyses with Kaplan-Meier-derived time-to-event data and meta-analysis with a random-effects model.

RESULTS

Thirteen studies met our eligibility criteria, incorporating 13 409 and 13 450 patients in the OSR and EVAR arms, respectively. Patients who underwent open repair had improved overall survival rates compared with those who underwent EVAR (hazard ratio [HR]=0.93, 95% confidence interval [CI]=0.88-0.98, p=0.004) during a mean follow-up of 53.8 (SD=29.8) months and this was validated by the 2-stage meta-analysis (HR=0.89, 95% CI=0.8-0.99, p=0.03, I2=62.25%). Splitting timepoint analysis suggested that EVAR offers better survival outcome compared with OSR in the first 11 months following elective intervention (HR=1.37, 95% CI=1.22-1.54, p<0.0001), while OSR offers a significant survival advantage after the 11-month timepoint and up to 180 months (HR=0.84, 95% CI=0.8-0.89, p<0.0001). Similarly, freedom from reintervention was found to be significantly better in EVAR patients (HR=1.28, 95% CI=1.14-1.44, p<0.0001) within the first 30 days. After the first month postrepair, however, OSR demonstrated higher freedom-from-reintervention rates compared with EVAR that remained significant for up to 168 months during follow-up (HR=0.73, 95% CI=0.66-0.79, p<0.0001).

CONCLUSIONS

Despite the first-year survival advantage of EVAR in patients undergoing elective AAA repair, OSR was associated with a late survival benefit and decreased risk for reintervention in long-term follow-up.

CLINICAL IMPACT

Open surgical repair for uncomplicated abdominal aortic aneurysm offers better long-term outcomes in terms of survival and freedom from reintervention rate compared to the endovascular approach but in the first year it carries a higher risk of mortality. The novelty of our study lies that instead of comparing study-level effect estimates, we analyzed reconstructed individual patient-level data. This offered us the opportunity to perform our analyses with mathematically robust and flexible survival models, which was proved to be crucial since there was evidence of different hazard over time. Our findings underline the need for additional investigation to clarify the significance of open surgical repair when compared to the latest endovascular devices and techniques within the evolving era of minimally invasive procedures.

Extracorporeal cardiopulmonary resuscitation versus conventional cardiopulmonary resuscitation in adults with cardiac arrest: a comparative meta-analysis and trial sequential analysis

BACKGROUND

Although outcomes of patients after cardiac arrest remain poor, studies have suggested that extracorporeal cardiopulmonary resuscitation (ECPR) might improve survival and neurological outcomes. We aimed to investigate any potential benefits of using ECPR over conventional cardiopulmonary resuscitation (CCPR) in patients with out-of-hospital cardiac arrest (OHCA) and in-hospital cardiac arrest (IHCA).

METHODS

In this systematic review and meta-analysis, we searched MEDLINE via PubMed, Embase, and Scopus from Jan 1, 2000, to April 1, 2023, for randomised controlled trials and propensity-score matched studies. We included studies comparing ECPR with CCPR in adults (aged ≥18 years) with OHCA and IHCA. We extracted data from published reports using a prespecified data extraction form. We did random-effects (Mantel-Haenszel) meta-analyses and rated the certainty of evidence using the Grading of Recommendations, Assessments, Developments, and Evaluations (GRADE) approach. We rated the risk of bias of randomised controlled trials using the Cochrane risk-of-bias 2.0 tool, and that of observational studies using the Newcastle-Ottawa Scale. The primary outcome was in-hospital mortality. Secondary outcomes included complications during extracorporeal membrane oxygenation, short-term (from hospital discharge to 30 days after cardiac arrest) and long-term (≥90 days after cardiac arrest) survival with favourable neurological outcomes (defined as cerebral performance category scores 1 or 2), and survival at 30 days, 3 months, 6 months, and 1 year after cardiac arrest. We also did trial sequential analyses to evaluate the required information sizes in the meta-analyses to detect clinically relevant reductions in mortality.

FINDINGS

We included 11 studies (4595 patients receiving ECPR and 4597 patients receiving CCPR) in the meta-analysis. ECPR was associated with a significant reduction in overall in-hospital mortality (OR 0·67, 95% CI 0·51-0·87; p=0·0034; high certainty), without evidence of publication bias (pegger=0·19); the trial sequential analysis was concordant with the meta-analysis. When considering IHCA only, in-hospital mortality was lower in patients receiving ECPR than in those receiving CCPR (0·42, 0·25-0·70; p=0·0009), whereas when considering OHCA only, no differences were found (0·76, 0·54-1·07; p=0·12). Centre volume (ie, the number of ECPR runs done per year in each centre) was associated with reductions in odds of mortality (regression coefficient per doubling of centre volume -0·17, 95% CI -0·32 to -0·017; p=0·030). ECPR was also associated with an increased rate of short-term (OR 1·65, 95% CI 1·02-2·68; p=0·042; moderate certainty) and long-term (2·04, 1·41-2·94; p=0·0001; high certainty) survival with favourable neurological outcomes. Additionally, patients receiving ECPR had increased survival at 30-day (OR 1·45, 95% CI 1·08-1·96; p=0·015), 3-month (3·98, 1·12-14·16; p=0·033), 6-month (1·87, 1·36-2·57; p=0·0001), and 1-year (1·72, 1·52-1·95; p<0·0001) follow-ups.

INTERPRETATION

Compared with CCPR, ECPR reduced in-hospital mortality and improved long-term neurological outcomes and post-arrest survival, particularly in patients with IHCA. These findings suggest that ECPR could be considered for eligible patients with IHCA, although further research into patients with OHCA is warranted.

FUNDING

None.

The impact of theatre on social competencies: a meta-analytic evaluation

BACKGROUND

There has been agrowing interest in using artistic interventions as a method of developing interpersonal competence. This paper presents a meta-analysis evaluating the impact of theatre interventions on social competencies.

METHODS

Twenty-one primary studies totaling 4064 participants were included, presenting evidence available since 1983. Included studies were assessed in terms of quality, heterogeneity, and publication bias.

RESULTS

Our findings indicated that active theatre participation significantly improved participants' empathic abilities, social communication, tolerance, and social interactions, with the largest pooled effect size for social communication (0.698) and the smallest for tolerance (0.156). Our findings did not corroborate the impact of theatre on self-concept.

CONCLUSIONS

This paper shows that theatre interventions have a positive impact on social competencies. The paper makes a methodological contribution by showing that randomized and non-randomized studies yielded comparably valid results.

Using public clinical trial reports to probe non-experimental causal inference methods

BACKGROUND

Non-experimental studies (also known as observational studies) are valuable for estimating the effects of various medical interventions, but are notoriously difficult to evaluate because the methods used in non-experimental studies require untestable assumptions. This lack of intrinsic verifiability makes it difficult both to compare different non-experimental study methods and to trust the results of any particular non-experimental study.

METHODS

We introduce TrialProbe, a data resource and statistical framework for the evaluation of non-experimental methods. We first collect a dataset of pseudo "ground truths" about the relative effects of drugs by using empirical Bayesian techniques to analyze adverse events recorded in public clinical trial reports. We then develop a framework for evaluating non-experimental methods against that ground truth by measuring concordance between the non-experimental effect estimates and the estimates derived from clinical trials. As a demonstration of our approach, we also perform an example methods evaluation between propensity score matching, inverse propensity score weighting, and an unadjusted approach on a large national insurance claims dataset.

RESULTS

From the 33,701 clinical trial records in our version of the ClinicalTrials.gov dataset, we are able to extract 12,967 unique drug/drug adverse event comparisons to form a ground truth set. During our corresponding methods evaluation, we are able to use that reference set to demonstrate that both propensity score matching and inverse propensity score weighting can produce estimates that have high concordance with clinical trial results and substantially outperform an unadjusted baseline.

CONCLUSIONS

We find that TrialProbe is an effective approach for probing non-experimental study methods, being able to generate large ground truth sets that are able to distinguish how well non-experimental methods perform in real world observational data.

Fatal, ischemic and bleeding risk of patients meeting the selection criteria of the TWILIGHT trial: Insights from a large PCI registry

BACKGROUND

The TWILIGHT trial (NCT02270242) demonstrated that in selected high-risk patients undergoing percutaneous coronary intervention (PCI) ticagrelor monotherapy significantly reduced bleeding complications without ischemic harm as compared to ticagrelor plus aspirin after 3-month of dual antiplatelet therapy. The aim of this analysis was to assess the applicability of the findings TWILIGHT trial to a real-world population.

METHODS

Patients undergoing PCI at a tertiary center between 2012 and 2019 and not meeting any TWILIGHT exclusion criterion (oral anticoagulation treatment, ST-segment elevation myocardial infarction [MI], cardiogenic shock, dialysis, prior stroke, or thrombocytopenia) were included. Patients were stratified into 2 groups based on whether they fulfilled the TWILIGHT inclusion criteria (high-risk) or not (low-risk). The primary outcome was all-cause death; the key secondary outcomes were MI and major bleeding at 1 year after PCI.

RESULTS

Out of 13,136 included patients, 11,018 (83%) were at high risk. At 1-year, these patients had an approximately 3 folds greater hazard of death (1.4% vs 0.4%, HR 3.63, 95% CI 1.70-7.77) and MI (1.8% vs 0.6%, HR 2.81, 95% CI 1.56-5.04) and a nearly 2 folds higher risk of major bleeding (3.3% vs 1.8%, HR 1.86, 95% CI 1.32-2.62) as compared to low-risk patients.

CONCLUSION

Among patients not meeting the TWILIGHT exclusion criteria from a large PCI registry, the high-risk inclusion criteria of the TWILIGHT trial were met by the majority of patients and were associated with an increased risk of mortality and MI and a moderately elevated risk of bleeding.

Complementary evidence on the performance of coronary stents generated by a randomized controlled trial and a worldwide registry

BACKGROUND

Large-scale registries can provide valuable complementary data to randomized controlled trials (RCT) for the postmarketing evaluation of coronary stents, but their scientific relevance remains debated.

METHODS

We sought to compare the evidence on the performance of a single coronary stent platform generated by the RCT for its regulatory approval and a well-conducted international registry. Patients treated with the Ultimaster coronary stent in the CENTURY II (CII-UM) trial (n = 551) were compared to patients in the real-world e-ULTIMASTER (e-UM) registry (n = 35,389). All major events were adjudicated by an independent clinical event committee in both studies. Propensity weighted analysis was used to balance baseline and procedural differences between the 2 populations.

RESULTS

Coronary artery disease was more complex in e-UM compared to CII-UM, including more acute coronary syndromes, multivessel disease, left main, arterial, or venous grafts, and chronic total occlusions (P < .005 for all). At one-year follow-up and after excluding periprocedural myocardial infarction (MI) there was no statistically significant difference between CII-UM and e-UM regarding all-cause death (hazard ratio [HR] 0.55, 95% confidence interval [CI] 0.26-1.20, P = .14), cardiac death (HR 0.71, 95% CI 0.29-1.72, P = .45), target lesion failure (HR 1.18, 95% CI 0.78-1.78, P = .44), and target vessel MI (HR 0.76, 95% CI 0.24-2.38, P = .63). However, target vessel revascularization rate was significantly higher in CII-UM than in e-UM, HR 1.78, 95% CI 1.23-2.56, P = .002.

CONCLUSIONS

A well-conducted large-scale registry can provide valuable complementary evidence to RCTs on the postmarket performance of new coronary stents, across a wider range of uses and various geographic areas.

Efficacy and Safety of Oral Anticoagulants in Older Adult Patients With Atrial Fibrillation: Pairwise and Network Meta-Analyses

OBJECTIVE

To evaluate the efficacy and safety of oral anticoagulants for older adult patients with atrial fibrillation (AF).

DESIGN

Pairwise and network meta-analyses.

SETTING AND PARTICIPANTS

Patients with AF aged ≥75 years.

METHODS

PubMed, Embase, and the Cochrane library were searched for published randomized controlled trials and adjusted observational studies evaluating the use of a non-vitamin K antagonist oral anticoagulants (NOACs), vitamin K antagonist, or antiplatelet drug for the prevention of stroke. The primary efficacy and safety outcomes were the composite of stroke and systemic embolism (SSE) and major bleedings.

RESULTS

This study included 38 studies enrolling 1,022,908 older adult patients with AF. Results from pairwise meta-analyses showed that NOACs were superior to warfarin for all outcomes, except that dabigatran increased the risk of gastrointestinal (GI) bleedings. Aspirin was associated with a higher risk of SSE and ischemic stroke than warfarin or NOACs. Results of network meta-analyses indicated that apixaban significantly reduced the risk of SSE, major bleedings, and GI bleedings than warfarin, rivaroxaban, and dabigatran. Apixaban, edoxaban, rivaroxaban, and dabigatran reduced the risk of ischemic stroke and intracranial bleeding compared to warfarin. Dabigatran showed lower risk of all-cause mortality than warfarin and of intracranial bleeding than rivaroxaban.

CONCLUSIONS AND IMPLICATIONS

NOACs are of at least equal efficacy, or even superior to warfarin. The safety profile of individual NOAC agents was significantly different, as apixaban performs better than the other oral anticoagulants in reducing major bleeding and GI bleeding, whereas dabigatran increased the risk of GI bleeding.

Hierarchical network meta-analysis models for synthesis of evidence from randomised and non-randomised studies

BACKGROUND

With the increased interest in the inclusion of non-randomised data in network meta-analyses (NMAs) of randomised controlled trials (RCTs), analysts need to consider the implications of the differences in study designs as such data can be prone to increased bias due to the lack of randomisation and unmeasured confounding. This study aims to explore and extend a number of NMA models that account for the differences in the study designs, assessing their impact on the effect estimates and uncertainty.

METHODS

Bayesian random-effects meta-analytic models, including naïve pooling and hierarchical models differentiating between the study designs, were extended to allow for the treatment class effect and accounting for bias, with further extensions allowing for bias terms to vary depending on the treatment class. Models were applied to an illustrative example in type 2 diabetes; using data from a systematic review of RCTs and non-randomised studies of two classes of glucose-lowering medications: sodium-glucose co-transporter 2 inhibitors and glucagon-like peptide-1 receptor agonists.

RESULTS

Across all methods, the estimated mean differences in glycated haemoglobin after 24 and 52 weeks remained similar with the inclusion of observational data. The uncertainty around these estimates reduced when conducting naïve pooling, compared to NMA of RCT data alone, and remained similar when applying hierarchical model allowing for class effect. However, the uncertainty around these effect estimates increased when fitting hierarchical models allowing for the differences in study design. The impact on uncertainty varied between treatments when applying the bias adjustment models. Hierarchical models and bias adjustment models all provided a better fit in comparison to the naïve-pooling method.

CONCLUSIONS

Hierarchical and bias adjustment NMA models accounting for study design may be more appropriate when conducting a NMA of RCTs and observational studies. The degree of uncertainty around the effectiveness estimates varied depending on the method but use of hierarchical models accounting for the study design resulted in increased uncertainty. Inclusion of non-randomised data may, however, result in inferences that are more generalisable and the models accounting for the differences in the study design allow for more detailed and appropriate modelling of complex data, preventing overly optimistic conclusions.

Pharmaceutical treatment of osteoarthritis

OBJECTIVE

To review the current state of pharmaceutical treatment recommendations for the management of osteoarthritis.

METHOD

A narrative review was drafted to describe treatment guidelines, mechanism of action, pharmacokinetics, and toxicity for nine classes of pharmaceuticals: 1) oral nonsteroidal anti-inflammatory drugs (NSAIDs), 2) topical NSAIDs, 3) COX-2 inhibitors, 4) duloxetine, 5) intra-articular corticosteroids, 6) intra-articular hyaluronic acid, 7) acetaminophen (paracetamol), 8) tramadol, and 9) capsaicin.

RESULTS

In general, oral and topical NSAIDs, including COX-2 inhibitors, are strongly recommended first-line treatments for osteoarthritis due to their ability to improve pain and function but are associated with increased risks in patients with certain comorbidities (e.g., heightened cardiovascular risks). Intra-articular corticosteroid injections are generally recommended for osteoarthritis management and have relatively minor adverse effects. Other treatments, such as capsaicin, tramadol, and acetaminophen, are more controversial, and many updated guidelines offer differing recommendations.

CONCLUSION

The pharmaceutical management of osteoarthritis is a constantly evolving field. Promising treatments are emerging, and medicines that were once considered conventional (e.g., acetaminophen) are gradually becoming less acceptable based on concerns with efficacy and safety. Clinicians need to consider the latest evidence and recommendations to make an informed decision with their patients about how to optimize treatment plans for patients with knee, hip, polyarticular, or hand osteoarthritis.

Clinical Outcomes After Aggressive Active Early Motion and Modified Kleinert Regimens: Comparison of 2 Consecutive Cohorts

BACKGROUND

Modern multistrand repairs can withstand forces present in active flexion exercises, and this may improve the outcomes of flexor tendon repairs. We developed a simple home-based exercise regimen with free wrist and intrinsic minus splint aimed at facilitating the gliding of the flexor tendons and compared the outcomes with the modified Kleinert regimen used previously in the same institution.

METHODS

We searched the hospital database to identify flexor tendon repair performed before and after the new regimen was implemented and invited all patients to participate. The primary outcome was total active range of motion, and secondary outcomes were Disabilities of Arm, Shoulder, and Hand; grip strength; globally perceived function; and the quality of life.

RESULTS

The active range of motion was comparable between the groups (mean difference = 14; 95% confidence interval [CI], -8 to 36; P = .22). Disabilities of Arm, Shoulder, and Hand; grip strength; global perceived function; and health-related quality of life were also comparable between the groups. There was 1 (5.3%) rupture in the modified Kleinert group and 4 (15.4%) in the early active motion group (relative risk = 0.3; 95% CI, 0.04-2.5; P = .3).

CONCLUSIONS

Increasing active gliding with a free wrist and intrinsic minus splint did not improve the clinical outcomes after flexor tendon injury at a mean of 38-month follow-up.

Meta-analysis: Chemoprevention of hepatocellular carcinoma with statins, aspirin and metformin

BACKGROUND

Emerging data suggest that statins, aspirin and metformin may protect against hepatocellular carcinoma (HCC) development. However, prior meta-analyses were limited by heterogeneity and inclusion of studies without adequate adjustment for baseline risks.

AIM

To examine by an updated meta-analysis the association between these medications and HCC risk.

METHODS

Medline and Embase databases were searched from inception to March 2022 for studies that balanced baseline risks between study groups via propensity score matching or inverse probability of treatment weighting, that reported the impact of statins, aspirin or metformin on HCC risk. Multivariable-adjusted hazard ratios (HRs) for HCC were pooled using a random effects model.

RESULTS

Statin use was associated with reduced HCC risk overall (HR: 0.52; 95% CI: 0.37-0.72) (10 studies, 1,774,476), and in subgroup analyses for cirrhosis, hepatitis B/C, non-alcoholic fatty liver disease, studies accounting for concurrent aspirin and metformin consumption and lipophilic statins. Aspirin use was associated with reduced HCC risk overall (HR: 0.48; 95% CI: 0.27-0.87) (11 studies, 2,190,285 patients) but not in studies accounting for concurrent statin and metformin use. Metformin use was not associated with reduced HCC risk overall (HR: 0.57; 95% CI: 0.31-1.06) (3 studies, 125,458 patients). Most analyses had moderate/substantial heterogeneity, except in follow-up <60 months for aspirin (I2  = 0%).

CONCLUSION

Although statin and aspirin use were associated with reduced HCC risk, only statin use was significant in subgroup analyses accounting for concurrent medications. Metformin use was not associated with reduced HCC risk. These data have implications for future clinical trial design.

Study design methodology in neurosurgical research

Background

Medical research has evolved from individual expert-described opinions and techniques to scientifically designed methodology-based studies. There are different study designs, and selecting an appropriate study design is critical to appropriately answer the research question being investigated.

Main body

A research question may be addressed using different approaches that can be descriptive, analytical, or experimental. The choice of study design is influenced by features as that related to exposure (intervention) and disease (outcome); considerations related to time, resources, ethics and gaps in scientific knowledge that remain to be filled. The purpose of this review is to provide an overview of the basic study designs as it is the foundation of neurosurgical research to provide valid scientific evidence.

Conclusion

Quality in scientific research begins with a clear hypothesis and a well-formulated design. This entails a thorough understanding of the different study designs to choose the best suited to answer the investigated research question.

Impact of design characteristics among studies comparing coronary computed tomography angiography to noninvasive functional testing in chronic coronary syndromes

BACKGROUND

Coronary computed tomography angiography (CCTA) is widely adopted to detect obstructive coronary artery disease (CAD) in patients with chronic coronary syndromes (CCS). However, it is unknown to which extent study-specific characteristics yield different conclusions.

METHODS

We summarized non-randomized and randomized studies comparing CCTA and noninvasive functional testing for CCS with information on the outcome of myocardial infarction (MI). We evaluated the differential effect according to study characteristics using random-effect meta-analysis with Hartung-Knapp-Sidik-Jonkman adjustments.

RESULTS

Fifteen studies (8 non-randomized, 7 randomized) were included. CCTA was associated with decrease in relative (odds ratio (OR) 0.54, 95%CI 0.47 to 0.62, P < .001) and absolute MI risk (risk difference (RD) -0.4%, 95%CI -0.6 to -0.1, P = .005). The results remained consistent among the non-randomized (RD -0.4%, 95%CI -0.7 to -0.1, P=.029), but not among the randomized trials where there was no difference in the observed risk (RD 0.2%, 95%CI -0.6 to 0.1, P = .158). CCTA was not associated with MI reduction in studies with clinical outcome definition (OR 0.77, 95%CI 0.41 to 1.44, P = .212), research driven follow-up (OR 0.54, 95%CI 0.24 to 1.21, P = .090), central event assessment (OR 0.63, 95%CI 0.21 to 1.86, P = .207), outcome adjudication (OR 0.74, 95%CI 0.24 to 2.23, P = .178), or at low-risk of bias (OR 0.74, 95%CI 0.24 to 2.23, P = .178).

CONCLUSIONS

Among studies of any design, CCTA was associated with lower risk of MI in CCS compared to noninvasive functional testing. This benefit was diminished among studies with clinical outcome definition, central outcome assessment/adjudication or at low-risk of bias.

Studies with statistically significant effect estimates are more frequently published compared to non-significant estimates in oral health journals

BACKGROUND

Studies reporting statistically significant effect estimates tend to be more frequently published compared to studies reporting non-significant or equivalent estimates. Consequently, this may lead to distortion of the literature. The aim of this study is to assess the prevalence of reporting statistically significant effect estimates in leading oral health journals and to explore associations between the effect estimates and record characteristics.

METHODS

An electronic database search was undertaken of a selection of leading oral health journals including general oral health journals to identify primary oral health records published in 2019. Descriptive statistics and population average GEE logistic regression model was used to assess associations between articles reporting a statistically significant effect estimate and the record characteristics.

RESULTS

In 1335 records, 82.4% records reported a statistically significant effect estimate. All speciality journals compared to general oral health journals were less likely to publish a record with significant effect estimates. Authors based in Asia or other (OR 1.49; 95% CI :1.02,2.19; p = 0.037) were more likely to report significant effect estimates compared to those based in Europe. Interventional (OR 0.35; 0.22,0.58; p < 0.001) and observational (OR 0.56; 0.36, 0.89; p = 0.013) records were less likely to report significant effect estimates compared to in-vitro studies. Registered records were less likely to report significant effect estimates when compared to non-registered studies (OR 0.22; 95% CI :0.14,0.32; p < 0.001).

CONCLUSION

The publishing of records with significant effect estimates is prevalent within the oral health literature. To reduce dissemination bias and overestimation of effect sizes in systematic reviews, the publishing of studies with non-significant or equivalent effect estimates should be encouraged.

An empirical comparison of the harmful effects for randomized controlled trials and non-randomized studies of interventions

Introduction: Randomized controlled trials (RCTs) are the gold standard to evaluate the efficacy of interventions (e.g., drugs and vaccines), yet the sample size of RCTs is often limited for safety assessment. Non-randomized studies of interventions (NRSIs) had been proposed as an important alternative source for safety assessment. In this study, we aimed to investigate whether there is any difference between RCTs and NRSIs in the evaluation of adverse events. Methods: We used the dataset of systematic reviews with at least one meta-analysis including both RCTs and NRSIs and collected the 2 × 2 table information (i.e., numbers of cases and sample sizes in intervention and control groups) of each study in the meta-analysis. We matched RCTs and NRSIs by their sample sizes (ratio: 0.85/1 to 1/0.85) within a meta-analysis. We estimated the ratio of the odds ratios (RORs) of an NRSI against an RCT in each pair and used the inverse variance as the weight to combine the natural logarithm of ROR (lnROR). Results: We included systematic reviews with 178 meta analyses, from which we confirmed 119 pairs of RCTs and NRSIs. The pooled ROR of NRSIs compared to that of RCTs was estimated to be 0.96 (95% confidence interval: 0.87 and 1.07). Similar results were obtained with different sample size subgroups and treatment subgroups. With the increase in sample size, the difference in ROR between RCTs and NRSIs decreased, although not significantly. Discussion: There was no substantial difference in the effects between RCTs and NRSIs in safety assessment when they have similar sample sizes. Evidence from NRSIs might be considered a supplement to RCTs for safety assessment.

Comparison Between Minimally Invasive Right Anterior and Right Posterior Sectionectomy vs Right Hepatectomy: An International Multicenter Propensity Score-Matched and Coarsened-Exact-Matched Analysis of 1,100 Patients

BACKGROUND

The role of minimally invasive right anterior and right posterior sectionectomy (MI-RAS/MI-RPS) for right-sided liver lesions remains debatable. Although technically more demanding, these procedures might result in faster recovery and lower postoperative morbidity compared with minimally invasive right hemihepatectomy.

STUDY DESIGN

This is an international multicenter retrospective analysis of 1,114 patients undergoing minimally invasive right hemihepatectomy, MI-RAS, and MI-RPS at 21 centers between 2006 and 2019. Minimally invasive surgery included pure laparoscopic, robotic, hand-assisted, or a hybrid approach. A propensity-matched and coarsened-exact-matched analysis was performed.

RESULTS

A total of 1,100 cases met study criteria, of whom 759 underwent laparoscopic, 283 robotic, 11 hand-assisted, and 47 laparoscopic-assisted (hybrid) surgery. There were 632 right hemihepatectomies, 373 right posterior sectionectomies, and 95 right anterior sectionectomies. There were no differences in baseline characteristics after matching. In the MI-RAS/MI-RPS group, median blood loss was higher (400 vs 300 mL, p = 0.001) as well as intraoperative blood transfusion rate (19.6% vs 10.7%, p = 0.004). However, the overall morbidity rate was lower including major morbidity (7.1% vs 14.3%, p = 0.007) and reoperation rate (1.4% vs 4.6%, p = 0.029). The rate of close/involved margins was higher in the MI-RAS/MI-RPS group (23.4% vs 8.9%, p < 0.001). These findings were consistent after both propensity and coarsened-exact matching.

CONCLUSIONS

Although technically more demanding, MI-RAS/MI-RPS is a valuable alternative for minimally invasive right hemihepatectomy in right-sided liver lesions with lower postoperative morbidity, possibly due to the preservation of parenchyma. However, the rate of close/involved margins is higher in these procedures. These findings might guide surgeons in preoperative counselling and in selecting the appropriate procedure for their patients.

Laparoscopic versus open liver resection for hepatocellular carcinoma in elderly patients: A systematic review and meta-analysis of propensity score-matched studies

Purpose

Laparoscopic liver resection (LLR) is a widely practiced therapeutic method and holds several advantages over open liver resection (OLR) including less postoperative pain, lower morbidity, and faster recovery. However, the effect of LLR for the treatment of hepatocellular carcinoma (HCC) in elderly patients remains controversial. Therefore, we aimed to perform the first meta-analysis of propensity score-matched (PSM) studies to compare the short- and long-term outcomes of LLR versus OLR for elderly patients with HCC.

Methods

Databases including PubMed, Embase, Scopus, and Cochrane Library were systematically searched until April 2022 for eligible studies that compared LLR and OLR for the treatment of HCC in elderly patients. Short-term outcomes include postoperative complications, blood loss, surgical time, and length of hospital stay. Long-term outcomes include overall survival (OS) rate and disease-free survival (DFS) rate at 1, 3, and 5 years.

Results

A total of 12 trials involving 1,861 patients (907 in the LLR group, 954 in the OLR group) were included. Compared with OLR, LLR was associated with lower postoperative complications (OR 0.49, 95% CI 0.39 to 0.62, P &lt; 0.00001, I2 = 0%), less blood loss (MD −285.69, 95% CI −481.72 to −89.65, P = 0.004, I2 = 96%), and shorter hospital stay (MD −7.88, 95% CI −11.38 to −4.37, P &lt; 0.0001, I2 = 96%), whereas operation time (MD 17.33, 95% CI −6.17 to 40.83, P = 0.15, I2 = 92%) was insignificantly different. Furthermore, there were no significant differences for the OS and DFS rates at 1, 3, and 5 years.

Conclusions

For elderly patients with HCC, LLR offers better short-term outcomes including a lower incidence of postoperative complications and shorter hospital stays, with comparable long-term outcomes when compared with the open approach. Our results support the implementation of LLR for the treatment of HCC in elderly patients.

Systematic review registration

https://inplasy.com/inplasy-2022-4-0156/, identifier INPLASY202240156.

Microaxial Left Ventricular Assist Device in Cardiogenic Shock: A Systematic Review and Meta-Analysis

Microaxial left ventricular assist devices (LVAD) are increasingly used to support patients with cardiogenic shock; however, outcome results are limited to single-center studies, registry data and select reviews. We conducted a systematic review and meta-analysis, searching three databases for relevant studies reporting on microaxial LVAD use in adults with cardiogenic shock. We conducted a random-effects meta-analysis (DerSimonian and Laird) based on short-term mortality (primary outcome), long-term mortality and device complications (secondary outcomes). We assessed the risk of bias and certainty of evidence using the Joanna Briggs Institute and the GRADE approaches, respectively. A total of 63 observational studies (3896 patients), 6 propensity-score matched (PSM) studies and 2 randomized controlled trials (RCTs) were included (384 patients). The pooled short-term mortality from observational studies was 46.5% (95%-CI: 42.7–50.3%); this was 48.9% (95%-CI: 43.8–54.1%) amongst PSM studies and RCTs. The pooled mortality at 90 days, 6 months and 1 year was 41.8%, 51.1% and 54.3%, respectively. Hemolysis and access-site bleeding were the most common complications, each with a pooled incidence of around 20%. The reported mortality rate of microaxial LVADs was not significantly lower than extracorporeal membrane oxygenation (ECMO) or intra-aortic balloon pumps (IABP). Current evidence does not suggest any mortality benefit when compared to ECMO or IABP.

Limited liver resections in the posterosuperior segments: international multicentre propensity score-matched and coarsened exact-matched analysis comparing the laparoscopic and robotic approaches

Background

Limited liver resections (LLRs) for tumours located in the posterosuperior segments of the liver are technically demanding procedures. This study compared outcomes of robotic (R) and laparoscopic (L) LLR for tumours located in the posterosuperior liver segments (IV, VII, and VIII).

Methods

This was an international multicentre retrospective analysis of patients who underwent R-LLR or L-LLR at 24 centres between 2010 and 2019. Patient demographics, perioperative parameters, and postoperative outcomes were analysed; 1 : 3 propensity score matching (PSM) and 1 : 1 coarsened exact matching (CEM) were performed.

Results

Of 1566 patients undergoing R-LLR and L-LLR, 983 met the study inclusion criteria. Before matching, 159 R-LLRs and 824 L-LLRs were included. After 1 : 3 PSM of 127 R-LLRs and 381 L-LLRs, comparison of perioperative outcomes showed that median blood loss (100 (i.q.r. 40–200) versus 200 (100–500) ml; P = 0.003), blood loss of at least 500 ml (9 (7.4 per cent) versus 94 (27.6 per cent); P &lt; 0.001), intraoperative blood transfusion rate (4 (3.1 per cent) versus 38 (10.0 per cent); P = 0.025), rate of conversion to open surgery (1 (0.8 per cent) versus 30 (7.9 per cent); P = 0.022), median duration of Pringle manoeuvre when applied (30 (20–46) versus 40 (25–58) min; P = 0.012), and median duration of operation (175 (130–255) versus 224 (155–300); P &lt; 0.001) were lower in the R-LLR group compared with the L-LLR group. After 1 : 1 CEM of 104 R-LLRs with 104 L-LLRs, R-LLR was similarly associated with significantly reduced blood loss and a lower rate of conversion to open surgery.

Conclusion

Based on a matched analysis of well selected patients, both robotic and laparoscopic access could be undertaken safely with good outcomes for tumours in the posterosuperior liver segments.

A systematic review and meta-analysis of treatments for rapid cycling bipolar disorder

OBJECTIVES

Rapid cycling is a common and disabling phenomenon in individuals with bipolar disorders. In the absence of a recent literature examination, this systematic review and meta-analysis aimed to synthesise the evidence of efficacy, acceptability and tolerability of treatments for individuals with rapid cycling bipolar disorder (RCBD).

METHOD

A systematic search was conducted to identify randomised controlled trials assigning participants with RCBD to pharmacological and/or non-pharmacological interventions. Study inclusion and data extraction were undertaken by two reviewers independently. The primary outcome was continuous within-subject RCBD illness severity before and after treatment. Pre-post random effects meta-analyses were conducted for each outcome/intervention arm studied, generating a standardised effect size (hedge's g) and 95% confidence interval (CI).

RESULTS

A total of 34 articles describing 30 studies were included. A total of 16 separate pharmacological treatments were examined in contrast to 1 psychological therapy study. Only quetiapine and lamotrigine were assessed in >5 studies. By assessing 95% CI overlap of within-subject efficacy effects compared to placebo, the only interventions suggesting significant depression benefits (placebo g = 0.60) were olanzapine (with/without fluoxetine; g = 1.01), citalopram (g = 1.10) and venlafaxine (g = 2.48). For mania, benefits were indicated for quetiapine (g = 1.01), olanzapine (g = 1.19) and aripiprazole (g = 1.09), versus placebo (g = 0.33). Most of these effect sizes were from only one trial per treatment. Heterogeneity between studies was variable, and 20% were rated to have a high risk of bias.

CONCLUSIONS

While many interventions appeared efficacious, there was a lack of robust evidence for most treatments. Given the limited and heterogeneous evidence base, the optimal treatment strategies for people with RCBD are yet to be established.

Quadriceps Tendon Autograft Versus Bone-Patellar Tendon-Bone and Hamstring Tendon Autografts for Anterior Cruciate Ligament Reconstruction: A Systematic Review and Meta-analysis

BACKGROUND

The best type of autograft for anterior cruciate ligament (ACL) reconstruction remains debatable.

HYPOTHESIS

Compared with bone-patellar tendon-bone (BPTB) and hamstring tendon (HT) autografts, the quadriceps tendon (QT) autograft has comparable graft survival as well as clinical function and pain outcomes.

STUDY DESIGN

Meta-analysis; Level of evidence, 4.

METHODS

A systematic literature search was conducted in PubMed, Embase, Scopus, and the Cochrane Library to July 2020. Randomized controlled trials (RCTs) and observational studies reporting comparisons of QT versus BPTB or HT autografts for ACL reconstruction were included. All analyses were stratified according to study design: RCTs or observational studies.

RESULTS

A total of 24 studies were included: 7 RCTs and 17 observational studies. The 7 RCTs included 388 patients, and the 17 observational studies included 19,196 patients. No significant differences in graft failure (P = .36), the International Knee Documentation Committee (IKDC) subjective score (P = .39), or the side-to-side difference in stability (P = .60) were noted between QT and BPTB autografts. However, a significant reduction in donor site morbidity was noted in the QT group compared with the BPTB group (risk ratio [RR], 0.17 [95% CI, 0.09-0.33]; P < .001). No significant differences in graft failure (P = .57), the IKDC subjective score (P = .25), or the side-to-side stability difference (P = .98) were noted between QT and HT autografts. However, the QT autograft was associated with a significantly lower rate of donor site morbidity than the HT autograft (RR, 0.60 [95% CI, 0.39-0.93]; P = .02). A similar graft failure rate between the QT and control groups was observed after both early and late full weightbearing, after early and late full range of motion, and after using the QT autograft with a bone plug and all soft tissue QT grafts. However, a significantly lower rate of donor site morbidity was observed in the QT group compared with the control group after both early and late full weightbearing, after early and late full range of motion, and after using the QT autograft with a bone plug and all soft tissue QT grafts. No difference in effect estimates was seen between RCTs and observational studies.

CONCLUSION

The QT autograft had comparable graft survival, functional outcomes, and stability outcomes compared with BPTB and HT autografts. However, donor site morbidity was significantly lower with the QT autograft than with BPTB and HT autografts.

Clinical outcomes in the surgical management of ankle fractures: A systematic review and meta-analysis of fibular intramedullary nail fixation vs. open reduction and internal fixation in randomized controlled trials

BACKGROUND

What level I evidence exists to support the use of FNF for surgical management of ankle fractures in high risk patients? The purpose of this study was to compare clinical outcomes following fibular intramedullary nail fixation (FNF) and open reduction and internal fixation (ORIF) of ankle fractures.

METHODS

A systematic review of the current literature was performed according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Certainty of evidence reported according to GRADE (Grading of Recommendations Assessment, Development, and Evaluation). Our primary hypothesis was that patients undergoing FNF procedures to manage an ankle fracture would have significantly higher patient reported outcome scores (PROs) than patients undergoing ORIF. Primary study outcome measures were validated PROs. Secondary outcome measures included complication rate, secondary surgery rate, and bony union.

RESULTS

The primary outcome analysis revealed no evidence of a significant effect difference on Olerud and Molander Ankle Score (OMAS) PRO and no evidence of statistical heterogeneity. Secondary outcome analysis revealed a significant 0.30 (0.12-0.74 95CI) relative risk reduction for complications in FNF (P = 0.008). No evidence of an effect difference for bony union. The GRADE certainty of the evidence was rated as low for bone union. No evidence of reporting bias was appreciated. Sensitivity analyses did not significantly alter effect estimates.

CONCLUSION

This systematic review and meta-analysis restricted to evidence derived from RCTs revealed that the quality of evidence is reasonably strong and likely sufficient to conclude: (1) there is likely no clinically important difference between FNF and ORIF up to 12 months post-operatively, as defined by OMS (moderate certainty); (2) surgeons may reasonably expect reduced complications in 14 out of every 100 patients treated with FNF (moderate certainty); (3) there is likely no difference in bony union (low certainty). Future studies should investigate more patient-centered outcomes and if short-term findings are durable over time if these findings apply to lower risk populations.

LEVEL OF EVIDENCE

Systematic review and meta-analysis of level I evidence.

Reverse shoulder arthroplasty vs. hemiarthroplasty for the treatment of osteoporotic proximal humeral fractures in elderly patients: A systematic review and meta‑analysis update

The present meta-analysis was conducted to compare the safety and effectiveness of reverse shoulder arthroplasty (RSA) and hemiarthroplasty (HA) in the treatment of osteoporotic proximal humeral fractures in elderly patients. The Embase, Pubmed Central, Cumulative Index to Nursing and Allied Health Literature, ProQuest Dissertations and Theses, Cochrane Library and Chinese Biomedical databases were searched between January 2009 and January 2022 to identify relevant studies. According to the search strategy, a total of 210 associated studies were retrieved and 16 were finally included. Review Manager 5.4 software was used for the data analysis. This study indicated that patients in the RSA group had significantly improved treatment outcomes compared with patients in the HA group, as assessed by Constant-Murley Shoulder Outcome Score (95% CI, 1.69-3.76; P<0.001), American Shoulder and Elbow Surgeons score (95% CI, 11.81-24.88; P<0.001) and shoulder range of motion (ROM; 95% CI, 3.41-9.07; P<0.001). However, the HA group was superior to the RSA group in terms of the Oxford Shoulder score (95% CI, 2.89-11.11; P<0.001). There was no significant statistical difference between the two groups in terms of the Disabilities of the Arm, Shoulder and Hand score and complications. Overall, for the treatment of osteoporotic proximal humeral fractures in the elderly, the RSA group had improved postoperative ROM and functional scores compared with the HA group, without significant difference in the incidence of complications. However, HA remains a safe and reliable treatment option.

Efficacy and safety of corticosteroid regimens for the treatment of hospitalized COVID-19 patients: a meta-analysis

Aim

To evaluate the efficacy and safety of corticosteroids for treating hospitalized COVID-19 patients.

Materials & methods

Efficacy outcomes included time to negative SARS-CoV-2 tests, length of stay, duration and incidence of intensive unit care stay, incidence of mortality and duration and incidence of mechanical ventilation. Safety outcomes included the incidence of adverse events and severe adverse events, incidence of hyperglycemia and incidence of nosocomial infections.

Results

Ninety-five randomized controlled trials (RCTs) and observational studies (n = 42,205) were included. Corticosteroids were associated with increased length of stay (based on RCT only), increased time to negative tests, decreased length of mechanical ventilation and increased odds of hyperglycemia.

Conclusion

Corticosteroids should be considered in patients requiring mechanical ventilation, and glycemic monitoring may be needed when administering corticosteroids.

The effect of renin-angiotensin-aldosterone system inhibitors in patients with hypertension and COVID-19: A meta-analysis of randomized controlled trials and propensity score-matched studies

Background

High-quality evidence for whether the use of renin-angiotensin-aldosterone system (RAAS) inhibitors worsens clinical outcomes for patients with coronavirus disease 2019 (COVID-19) is lacking. The present study aimed to evaluate the effect of RAAS inhibitors on disease severity and mortality in patients with hypertension and COVID-19 using randomized controlled trials (RCTs) and propensity score-matched (PSM) studies.

Methods

A literature search was conducted with PubMed, Embase, and Scopus databases from 31 December 2019 to 10 January 2022. We included RCTs and PSM studies comparing the risk of severe illness or mortality in patients with hypertension and COVID-19 treated or not treated with RAAS inhibitors. Individual trial data were combined to estimate the pooled odds ratio (OR) with a random-effects model.

Results

A total of 17 studies (4 RCTs and 13 PSM studies) were included in the meta-analysis. The use of RAAS inhibitors was not associated with an increased risk of severe illness (OR=1.00, 95% confidence interval [CI]: 0.88-1.14, I²=28%) or mortality (OR=0.96, 95% CI: 0.83-1.11, I²=16%) for patients with hypertension and COVID-19. Furthermore, there was no significant difference in the severity of COVID-19 when patients continued or discontinued treatment with RAAS inhibitors (OR=1.01, 95% CI: 0.78-1.29, I²=0%).

Conclusions

This study suggests that there was no association between treatment with RAAS inhibitors and worsened COVID-19 disease outcomes. Our findings support the current guidelines that RAAS inhibitors should be continued in the setting of the COVID-19 pandemic. However, the benefit of RAAS inhibitor medications for COVID-19 patients should be further validated with more RCTs.

Direct oral anticoagulants in atrial fibrillation following cardiac surgery: a systematic review and meta-analysis with trial sequential analysis

BACKGROUND

Direct oral anticoagulants (DOACs) have been increasingly used as anticoagulation therapy in the postoperative period. However, their effectiveness in post-cardiac surgical atrial fibrillation is yet to be determined.

METHODS

We conducted a meta-analysis, searching three international databases from 1 January 2003 to 26 January 2022 for studies reporting on DOACs in at least 10 adult patients (>18 yr of age) with post-cardiac surgical atrial fibrillation. The primary outcomes were major neurological events (MNEs) and bleeding; secondary outcomes were mortality, hospital and ICU length of stay, cost, and other complications from therapy. We included studies of any design, including RCTs, cohort studies with and without propensity score matching methods, and single-armed case series.

RESULTS

Twelve studies (8587 DOACs; 8315 warfarin) were included in this meta-analysis. The incidences of postoperative bleeding and MNEs with DOACs were 7.3% (95% confidence interval [CI]: 3.4-14.7%) and 2.2% (95% CI: 0.9-4.9%), respectively. The incidence of MNEs was lower in high-risk patients, including those with hypertension and higher CHA₂DS₂-VASc score, whereas patients with prior transient ischaemic attack or stroke had higher incidence of bleeding. Trial sequential analysis revealed that the cumulative Z-curve crossed the conventional boundary of benefit. Compared with warfarin, DOACs reduced the risk of bleeding (relative risk [RR] 0.74; 95% CI: 0.62-0.89; P=0.0011) and MNEs (RR 0.63; 95% CI: 0.48-0.83; P=0.0012) but not mortality (RR 1.02; 95% CI: 0.77-1.35; P=0.090).

CONCLUSIONS

DOACs reduced bleeding and MNEs in patients with post-cardiac surgical atrial fibrillation, appearing safer than warfarin in this context. However, which DOAC provides the most effective anticoagulation in this patient population needs further investigation.

CLINICAL TRIAL REGISTRATION

PROSPERO CRD42021282777.

Risk of Hepatocellular Carcinoma With Tenofovir vs Entecavir Treatment for Chronic Hepatitis B Virus: A Reconstructed Individual Patient Data Meta-analysis

IMPORTANCE

Conventional meta-analyses with aggregated study-level data have yielded conflicting results for the comparative effectiveness of tenofovir disoproxil fumarate vs entecavir in reducing hepatocellular carcinoma (HCC) risk among patients with chronic hepatitis B virus. Within-study heterogeneity, between-study heterogeneity, and the inability of conventional meta-analyses to capture time-to-event data were associated with these results.

OBJECTIVE

To perform a reconstructed individual patient data meta-analysis of high-quality propensity score-matched studies to provide robust estimates for comparative HCC risk between groups receiving tenofovir or entecavir.

DATA SOURCES

Medline and Embase databases were searched from inception to October 6, 2021.

STUDY SELECTION

The initial search yielded 3435 articles. Fourteen studies that used propensity score matching to balance baseline characteristics were included in the final analysis.

DATA EXTRACTION AND SYNTHESIS

The Preferred Reporting Items for Systematic Reviews and Meta-analyses guideline was followed. Individual patient data were reconstructed from Kaplan-Meier curves. Risk of HCC was evaluated using random-effects hazard ratios (HRs) via a shared-frailty model and a Cox proportional hazards model stratified by study group. Restricted mean survival time (RMST) analysis was conducted to account for varying estimated treatment effect across time.

MAIN OUTCOMES AND MEASURES

The comparative risk of HCC with tenofovir vs entecavir treatment.

RESULTS

From analysis of 14 studes with 24 269 patients (10 534 receiving tenofovir and 13 735 receiving entecavir; mean age, 49.86 [95% CI, 48.35-51.36] years; 65.05% [95% CI, 58.60%-71.00%] men), tenofovir was associated with decreased HCC incidence compared with entecavir (stratified Cox HR, 0.85 [95% CI, 0.76-0.94] at 5 years; P = .002). However, there was no significant difference in subanalysis of clinical cohort studies (stratified Cox HR, 0.92 [95% CI, 0.80-1.06] at 5 years; P = .24). Among administrative database studies, proportionality was violated, and HRs could not be obtained via Cox proporational hazards-based models. The mean time to HCC development in RMST analysis was 2.8 (95% CI, 1.8-3.7) weeks longer (P < .001) for tenofovir vs entecavir at 5 years. The RMST analyses for other subgroups revealed either insignificant or minimal differences (<3 weeks) in the mean time to HCC at 5 years.

CONCLUSIONS AND RELEVANCE

In this meta-analysis, there was no clinically meaningful difference in the risk of HCC between patients who received entecavir and patients who received tenofovir. There was no difference between tenofovir and entecavir among clinical cohort studies, whereas the mean time to HCC development was less than 3 weeks longer for patients who received tenofovir vs those who received entecavir at year 5 among administrative database studies. The choice between tenofovir or entecavir should be decided based on patient convenience and tolerability.