On variance estimation of the inverse probability-of-treatment weighting estimator: A tutorial for different types of propensity score weights

Propensity score methods, such as inverse probability-of-treatment weighting (IPTW), have been increasingly used for covariate balancing in both observational studies and randomized trials, allowing the control of both systematic and chance imbalances. Approaches using IPTW are based on two steps: (i) estimation of the individual propensity scores (PS), and (ii) estimation of the treatment effect by applying PS weights. Thus, a variance estimator that accounts for both steps is crucial for correct inference. Using a variance estimator which ignores the first step leads to overestimated variance when the estimand is the average treatment effect (ATE), and to under or overestimated estimates when targeting the average treatment effect on the treated (ATT). In this article, we emphasize the importance of using an IPTW variance estimator that correctly considers the uncertainty in PS estimation. We present a comprehensive tutorial to obtain unbiased variance estimates, by proposing and applying a unifying formula for different types of PS weights (ATE, ATT, matching and overlap weights). This can be derived either via the linearization approach or M-estimation. Extensive R code is provided along with the corresponding large-sample theory. We perform simulation studies to illustrate the behavior of the estimators under different treatment and outcome prevalences and demonstrate appropriate behavior of the analytical variance estimator. We also use a reproducible analysis of observational lung cancer data as an illustrative example, estimating the effect of receiving a PET-CT scan on the receipt of surgery.

Towards the Lowest Efficacious Dose: Results From a Multicenter Noninferiority Randomized Open-Label Controlled Trial Assessing Tocilizumab or Abatacept Injection Spacing in Rheumatoid Arthritis in Remission

OBJECTIVE

We assess the clinical and structural impact at two years of progressively spacing tocilizumab (TCZ) or abatacept (ABA) injections versus maintenance at full dose in patients with rheumatoid arthritis in sustained remission.

METHODS

This multicenter open-label noninferiority (NI) randomized clinical trial included patients with established rheumatoid arthritis in sustained remission receiving ABA or TCZ at a stable dose. Patients were randomized to treatment maintenance (M) at full dose (M-arm) or progressive injection spacing (S) driven by the Disease Activity Score in 28 joints every 3 months up to biologics discontinuation (S-arm). The primary end point was the evolution of disease activity according to the Disease Activity Score in 44 joints during the 2-year follow-up analyzed per protocol with a linear mixed-effects model, evaluated by an NI test based on the one-sided 95% confidence interval (95% CI) of the slope difference (NI margin 0.25). Other end points were flare incidence and structural damage progression.

RESULTS

Overall, 202 of the 233 patients included were considered for per protocol analysis (90 in S-arm and 112 in M-arm). At the end of follow-up, 16.2% of the patients in the S-arm could discontinue their biologic disease-modifying antirheumatic drug, 46.9% tapered the dose and 36.9% returned to a full dose. NI was not demonstrated for the primary outcome, with a slope difference of 0.10 (95% CI 0.10-0.31) between the two arms. NI was not demonstrated for flare incidence (difference 42.6%, 95% CI 30.0-55.1) or rate of structural damage progression at two years (difference 13.9%, 95% CI -6.7 to 34.4).

CONCLUSION

The Towards the Lowest Efficacious Dose trial failed to demonstrate NI for the proposed ABA or TCZ tapering strategy.

Renal replacement therapy initiation strategies in comatose patients with severe acute kidney injury: a secondary analysis of a multicenter randomized controlled trial

PURPOSE

The effect of renal replacement therapy (RRT) in comatose patients with acute kidney injury (AKI) remains unclear. We compared two RRT initiation strategies on the probability of awakening in comatose patients with severe AKI.

METHODS

We conducted a post hoc analysis of a trial comparing two delayed RRT initiation strategies in patients with severe AKI. Patients were monitored until they had oliguria for more than 72 h and/or blood urea nitrogen higher than 112 mg/dL and then randomized to a delayed strategy (RRT initiated after randomization) or a more-delayed one (RRT initiated if complication occurred or when blood urea nitrogen exceeded 140 mg/dL). We included only comatose patients (Richmond Agitation-Sedation scale [RASS] < - 3), irrespective of sedation, at randomization. A multi-state model was built, defining five mutually exclusive states: death, coma (RASS < - 3), incomplete awakening (RASS [- 3; - 2]), awakening (RASS [- 1; + 1] two consecutive days), and agitation (RASS >  + 1). Primary outcome was the transition from coma to awakening during 28 days after randomization.

RESULTS

A total of 168 comatose patients (90 delayed and 78 more-delayed) underwent randomization. The transition intensity from coma to awakening was lower in the more-delayed group (hazard ratio [HR] = 0.36 [0.17-0.78]; p = 0.010). Time spent awake was 10.11 days [8.11-12.15] and 7.63 days [5.57-9.64] in the delayed and the more-delayed groups, respectively. Two sensitivity analyses were performed based on sedation status and sedation practices across centers, yielding comparable results.

CONCLUSION

In comatose patients with severe AKI, a more-delayed RRT initiation strategy resulted in a lower chance of transitioning from coma to awakening.

A methodological review of the high-dimensional propensity score in comparative-effectiveness and safety-of-interventions research finds incomplete reporting relative to algorithm development and robustness

OBJECTIVES

The use of secondary databases has become popular for evaluating the effectiveness and safety of interventions in real-life settings. However, the absence of important confounders in these databases is challenging. To address this issue, the high-dimensional propensity score (hdPS) algorithm was developed in 2009. This algorithm uses proxy variables for mitigating confounding by combining information available across several healthcare dimensions. This study assessed the methodology and reporting of the hdPS in comparative effectiveness and safety research.

STUDY DESIGN AND SETTING

In this methodological review, we searched PubMed and Google Scholar from July 2009 to May 2022 for studies that used the hdPS for evaluating the effectiveness or safety of healthcare interventions. Two reviewers independently extracted study characteristics and assessed how the hdPS was applied and reported. Risk of bias was evaluated with the Rrisk Of Bias In Non-randomised Studies - of Interventions (ROBINS-I) tool.

RESULTS

In total, 136 studies met the inclusion criteria; the median publication year was 2018 (Q1-Q3 2016-2020). The studies included 192 datasets, mostly North American databases (n = 132, 69%). The hdPS was used in primary analysis in 120 studies (88%). Dimensions were defined in 101 studies (74%), with a median of 5 (Q1-Q3 4-6) dimensions included. A median of 500 (Q1-Q3 200-500) empirically identified covariates were selected. Regarding hdPS reporting, only 11 studies (8%) reported all recommended items. Most studies (n = 81, 60%) had a moderate overall risk of bias.

CONCLUSION

There is room for improvement in the reporting of hdPS studies, especially regarding the transparency of methodological choices that underpin the construction of the hdPS.

High Airway Occlusion Pressure Is Associated with Dyspnea and Increased Mortality in Critically Ill Mechanically Ventilated Patients

RATIONALE

100 ms airway occlusion pressure (P0.1) reflects central respiratory drive. We aimed to assess factors associated with P0.1 and whether an abnormally low or high P0.1 value is associated with higher mortality and longer duration of mechanical ventilation (MV).

METHODS

Secondary analysis of a prospective cohort study conducted in 10 intensive care units in France to evaluate dyspnea in communicative MV patients. In patients intubated for more than 24 hours, P0.1 was measured with dyspnea as soon as patients could communicate and the following day.

RESULTS

260 patients were assessed after a median time of ventilation of 4 days. P0.1 was 1.9 (1 - 3.5) cmH2O on enrollment, 24% had a P0.1 >3.5 cmH2O, 37% had a P0.1 between 1.5 and 3.5 cmH2O, and 39% had a P0.1 <1.5 cmH2O. In multivariable linear regression, independent factors associated with P0.1 level were presence of dyspnea (p=0.037), respiratory rate (p<0.001), and PaO2 (p=0.008). 90-day mortality was 33% in patients with P0.1 >3.5 cmH2O vs. 19% in those with a P0.1 between 1.5 and 3.5 cmH2O and 17% in patients with P0.1 <1.5 cmH2O (p=0.046). After adjustment for the main risk factors, P0.1 was associated with 90-day mortality (per cmH2O of P0.1, Hazard ratio 1.19, 95% Confidence interval 1.04 - 1.37, p=0.011). P0.1 was also independently associated with a longer duration of MV (per cmH2O of P0.1, Hazard ratio 1.10, 95% Confidence interval 1.02-1.19, p=0.016).

CONCLUSIONS

In patients receiving invasive mechanical ventilation, abnormally high P0.1 values may suggest dyspnea and is associated with higher mortality and prolonged duration of MV.

Prone Positioning During Extracorporeal Membrane Oxygenation in Patients With Severe ARDS: The PRONECMO Randomized Clinical Trial

Importance

Prone positioning may improve outcomes in patients with severe acute respiratory distress syndrome (ARDS), but it is unknown whether prone positioning improves clinical outcomes among patients with ARDS who are undergoing venovenous extracorporeal membrane oxygenation (VV-ECMO) compared with supine positioning.

Objective

To test whether prone positioning vs supine positioning decreases the time to successful ECMO weaning in patients with severe ARDS supported by VV-ECMO.

Design, Setting, and Participants

Randomized clinical trial of patients with severe ARDS undergoing VV-ECMO for less than 48 hours at 14 intensive care units (ICUs) in France between March 3, 2021, and December 7, 2021.

Interventions

Patients were randomized 1:1 to prone positioning (at least 4 sessions of 16 hours) (n = 86) or to supine positioning (n = 84).

Main Outcomes and Measures

The primary outcome was time to successful ECMO weaning within 60 days following randomization. Secondary outcomes included ECMO and mechanical ventilation-free days, ICU and hospital length of stay, skin pressure injury, serious adverse events, and all-cause mortality at 90-day follow-up.

Results

Among 170 randomized patients (median age, 51 [IQR, 43-59] years; n = 60 women [35%]), median respiratory system compliance was 15.0 (IQR, 10.7-20.6) mL/cm H2O; 159 patients (94%) had COVID-19-related ARDS; and 164 (96%) were in prone position before ECMO initiation. Within 60 days of enrollment, 38 of 86 patients (44%) had successful ECMO weaning in the prone ECMO group compared with 37 of 84 (44%) in the supine ECMO group (risk difference, 0.1% [95% CI, -14.9% to 15.2%]; subdistribution hazard ratio, 1.11 [95% CI, 0.71-1.75]; P = .64). Within 90 days, no significant difference was observed in ECMO duration (28 vs 32 days; difference, -4.9 [95% CI, -11.2 to 1.5] days; P = .13), ICU length of stay, or 90-day mortality (51% vs 48%; risk difference, 2.4% [95% CI, -13.9% to 18.6%]; P = .62). No serious adverse events were reported during the prone position procedure.

Conclusions and Relevance

Among patients with severe ARDS supported by VV-ECMO, prone positioning compared with supine positioning did not significantly reduce time to successful weaning of ECMO.

Trial Registration

ClinicalTrials.gov Identifier: NCT04607551.

A methodological review of population-adjusted indirect comparisons reveals inconsistent reporting and suggests publication bias

OBJECTIVES

Population-adjusted indirect comparisons (PAICs) were developed in the 2010s to allow for comparisons between two treatments evaluated in different trials while accounting for differences in patient characteristics if individual patient data (IPD) are available for only one trial. Such comparisons are increasingly used in market access applications when a pharmaceutical company compares its new treatment (with IPD available) to another treatment developed by a competitor (with only aggregated data available). This study aimed to describe the characteristics of these PAICs, assess their methodology, and describe the reported results.

STUDY DESIGN AND SETTING

Original articles reporting the use of at least one PAIC were searched on PubMed between January 1, 2010 and April 2, 2022. Two reviewers independently selected articles and extracted data.

RESULTS

We included 133 publications reporting the results of 288 PAICs. Half of the articles were published on or after May 7, 2020, and 71 (53%) pertained to onco-hematology. The pharmaceutical industry was involved in 130 (98%) articles. Key methodological aspects were reported inconsistently, with only three articles adequately reporting all aspects. A total of 161 (56%) articles reported a statistically significant benefit for the treatment evaluated on IPD. Conversely, only one PAIC significantly favored the treatment evaluated on aggregated data.

CONCLUSION

Although the number of published PAICs is increasing, the methodology and transparency need to be improved. Moreover, our study strongly suggests a reporting bias. This situation calls for strengthening guidelines to improve trust in PAIC results and thus their reliability in market access applications.

Ability to predict rheumatoid arthritis relapse after tumour necrosis factor inhibitor tapering by the Multi-Biomarker Disease Activity Score: a post-hoc analysis of the STRASS trial

OBJECTIVES

The aim was to evaluate the ability of baseline multi-biomarker disease activity (MBDA) score to discriminate between patients with rheumatoid arthritis (RA) in remission who are at high risk versus low risk of relapse after TNF-inhibitor (TNFi) tapering.

METHODS

The study is a post-hoc analysis of patients who completed the Spacing of TNFi injections in Rheumatoid ArthritiS Study (STRASS), a multicentre 18-month equivalence randomised controlled study, of TNFi tapering in RA patients in remission, and had baseline serum samples available for MBDA testing. The primary endpoint of this study was the ability of the baseline MBDA score to predict relapse at any time during the 18 months following initiation of TNFi tapering. Secondary endpoints were the ability of baseline MBDA score to predict TNFi discontinuation at Month 18, and structural damage progression on x-rays assessed by the change in total van der Heijde-modified Sharp score from baseline to month 18.

RESULTS

64 and 73 patients were included in the spacing (S)-arm and maintenance (M)-arm, respectively. In the M-arm, the mean MBDA score at baseline was higher among patients who relapsed during the 18-month follow-up than those who did not relapse: 32.5 compared to 27.2 (p=0.053) whereas no difference in the MBDA score was observed in the S-arm between patients who relapsed or not 27 compared to 26.2 (p=0.57) 13 patients (21.3%) of the S-arm were able to discontinue TNFi, for which the predictive value of the MBDA score was low (AUC=0.560). Radiographic progression in both arms, although low (n=9) was not correlated with the MBDA score at baseline with a poor discriminative value in both arms (AUC=0.558).

CONCLUSIONS

In our study MBDA score in baseline was not predictive of relapse, discontinuation of TNFi in patients with long-standing RA patients tapering TNFi.

FX06 to rescue SARS-CoV-2-induced acute respiratory distress syndrome: a randomized clinical trial

BACKGROUND

Vascular leakage is a major feature of acute respiratory distress syndrome (ARDS). We aimed to evaluate the efficacy of FX06, a drug under development that stabilizes interendothelial cell junctions, at reducing vascular leakage during SARS-CoV-2-induced ARDS.

METHODS

This multicenter, double-blinded, randomized trial included adults with COVID-19-associated ARDS who had received invasive mechanical ventilation for < 5 days and were randomized to receive either intravenous FX06 (400 mg/d, for 5 days) or its vehicle as placebo. The primary endpoint was the lowering-from day 1 to day 7-of the transpulmonary thermodilution-derived extravascular lung-water index (EVLWi).

RESULTS

Twenty-five patients were randomized to receive FX06 and 24 the placebo. Although EVLWi was elevated at baseline (median [IQR] 15.6 mL/kg [13.5; 18.5]), its declines from day 1 to day 7 were comparable for FX06 recipients and controls (respectively, - 1.9 [- 3.3; - 0.5] vs. - 0.8 [- 5.5; - 1.1] mL/kg; estimated effect - 0.8 [- 3.1; + 2.4], p = 0.51). Cardiac indexes, pulmonary vascular permeability indexes, and fluid balances were also comparable, as were PaO2/FiO2 ratios and durations of mechanical ventilation. Adverse event rates were similar for the 2 groups, although more FX06 recipients developed ventilator-associated pneumonia (16/25 (64%) vs. 6/24 (24%), p = 0.009).

CONCLUSIONS

In this unique-dosing-regimen study, FX06 did not lower SARS-CoV-2-induced pulmonary vascular leakage. Future investigations will need to evaluate its efficacy at earlier times during the disease or using other regimens. Trial registration NCT04618042. Registered 5 November 2020.

COVID-19 trials were not more likely to report intent to share individual data than non-COVID-19 trials in ClinicalTrials.gov

OBJECTIVES

To compare intent to share individual participant data (IPD) between COVID-19 and non-COVID-19 trials registered at ClinicalTrials.gov between 01/09/2020, and 01/03/2021. We also evaluated factors independently associated with intent to share IPD and whether intent to share IPD has improved as compared with the prepandemic period.

METHODS

We searched ClinicalTrials.gov for all interventional phase 3 studies registered between 01/09/2020, and 01/03/2021. Then, we identified COVID-19 trials and selected a random sample of non-COVID-19 trials with a ratio 2:1. We compared the intent to share IPD between these trials and with 292 trials registered between 01/12/2019, and 01/03/2020 (prepandemic period).

RESULTS

We included 148 COVID-19 trials and 296 non-COVID-19 trials. Intent to share IPD did not significantly differ between COVID-19 and non-COVID-19 trials (22.3% vs. 27.0%, P = 0.3). Intent to share IPD was independently associated with industry-sponsorship (odds ratio [OR] = 2.92; 95% confidence interval [CI]: 1.65-5.27) and location in the United States (OR = 2.93; 95% CI: 1.64-5.41) or the European Union (OR = 2.06; 95% CI: 1.03-4.19). The intent to share IPD has not significantly improved compared with the prepandemic period (P = 0.16).

CONCLUSION

Data-sharing intent at registration does not seem better for COVID-19 trials.

Association Between Anti-CD20 Therapies and COVID-19 Severity Among Patients With Relapsing-Remitting and Progressive Multiple Sclerosis

Importance

In patients with multiple sclerosis (MS), factors associated with severe COVID-19 include anti-CD20 therapies and neurologic disability, but it is still unclear whether these 2 variables are independently associated with severe COVID-19 or whether the association depends on MS clinical course.

Objective

To assess the association between anti-CD20 therapies and COVID-19 severity in patients with relapsing-remitting MS (RRMS) and progressive MS (PMS).

Design, Setting, and Participants

This multicenter, retrospective cohort study used data from the COVISEP study, which included patients with MS and COVID-19 from February 1, 2020, to June 30, 2022, at 46 French MS expert centers, general hospitals, and private neurology practices. Eligible patients with RRMS were those treated with high-efficacy MS therapy (ie, anti-CD20, fingolimod, or natalizumab), and eligible patients with PMS were those younger than 70 years with an Expanded Disability Status Scale (EDSS) score of 8 or lower. Patients were monitored from COVID-19 symptom onset until recovery or death.

Exposures

Current anti-CD20 therapy (ocrelizumab or rituximab).

Main Outcomes and Measures

The main outcome was severe COVID-19 (ie, hospitalization with any mode of oxygenation or death). All analyses were conducted separately in patients with RRMS and PMS using propensity score-weighted logistic regression. Subgroup analyses were performed according to COVID-19 vaccine status, sex, EDSS score, and age.

Results

A total of 1400 patients, 971 with RRMS (median age, 39.14 years [IQR, 31.38-46.80 years]; 737 [76.1%] female) and 429 with PMS (median age, 54.21 years [IQR, 48.42-60.14 years]; 250 [58.3%] female) were included in the study. A total of 418 patients with RRMS (43.0%) and 226 with PMS (52.7%) were treated with anti-CD20 therapies. In weighted analysis, 13.4% and 2.9% of patients with RRMS treated and not treated with anti-CD20 had severe COVID-19, respectively, and anti-CD20 treatment was associated with increased risk of severe COVID-19 (odds ratio [OR], 5.20; 95% CI, 2.78-9.71); this association persisted among vaccinated patients (7.0% vs 0.9%; OR, 8.85; 95% CI, 1.26-62.12). Among patients with PMS, 19.0% and 15.5% of patients treated and not treated with anti-CD20 had severe COVID-19, respectively, and there was no association between anti-CD20 treatment and severe COVID-19 (OR, 1.28; 95% CI, 0.76-2.16). In PMS subgroup analysis, anti-CD20 exposure interacted negatively with EDSS score (P = .009 for interaction) and age (P = .03 for interaction); anti-CD20 therapies were associated with risk of severe COVID-19 only in patients with less neurologic disability and younger patients with PMS.

Conclusions and Relevance

In this cohort study, risk of severe COVID-19 was higher in patients with PMS than in those with RRMS. Use of anti-CD20 therapies was associated with an increased risk of severe COVID-19 among patients with RRMS. In patients with PMS, there was no association between anti-CD20 therapies and risk of severe COVID-19.

Impact of renal replacement therapy strategy on beta-lactam plasma concentrations: the BETAKIKI study-an ancillary study of a randomized controlled trial

BACKGROUND

Sepsis prognosis correlates with antibiotic adequacy at the early phase. This adequacy is dependent on antibacterial spectrum, bacterial resistance profile and antibiotic dosage. Optimal efficacy of beta-lactams mandates concentrations above the minimal inhibitory concentration (MIC) of the targeted bacteria for the longest time possible over the day. Septic acute kidney injury (AKI) is the most common AKI syndrome in ICU and often mandates renal replacement therapy (RRT) initiation. Both severe AKI and RRT may increase outside target antibiotic concentrations and ultimately alter patient's prognosis.

PATIENTS AND METHODS

This is a secondary analysis of a randomized controlled trial that compared an early RRT initiation strategy with a delayed one in 620 critically ill patients undergoing severe AKI (defined by KDIGO 3). We compared beta-lactam trough concentrations between the two RRT initiation strategies. The primary outcome was the proportion of patients with sufficient trough plasma concentration of beta-lactams defined by trough concentration above 4 times the MIC. We hypothesized that early initiation of RRT could be associated with an insufficient antibiotic plasma trough concentration compared to patients allocated to the delayed strategy.

RESULTS

One hundred and twelve patients were included: 53 in the early group and 59 in the delayed group. Eighty-three patients (74%) had septic shock on inclusion. Trough beta-lactam plasma concentration was above 4 times the MIC breakpoint in 80.4% (n = 90) of patients of the whole population, without differences between the early and the delayed groups (79.2% vs. 81.4%, respectively, p = 0.78). On multivariate analysis, the presence of septic shock and a higher mean arterial pressure were significantly associated with a greater probability of adequate antibiotic trough concentration [OR 3.95 (1.14;13.64), p = 0.029 and OR 1.05 (1.01;1.10), p = 0.013, respectively). Evolution of procalcitonin level and catecholamine-free days as well as mortality did not differ whether beta-lactam trough concentration was above 4 times the MIC or not.

CONCLUSIONS

In this secondary analysis of a randomized controlled trial, renal replacement therapy initiation strategy did not significantly influence plasma trough concentrations of beta-lactams in ICU patients with severe AKI. Presence of septic shock on inclusion was the main variable associated with a sufficient beta-lactam concentration.

TRIAL REGISTRATION

The AKIKI trial was registered on ClinicalTrials.gov (Identifier: NCT01932190) before the inclusion of the first patient.

Levosimendan in patients undergoing extracorporeal membrane oxygenation after cardiac surgery: an emulated target trial using observational data

BACKGROUND

Retrospective cohorts have suggested that levosimendan may facilitate the weaning of veno-arterial extracorporeal membrane oxygenation (VA-ECMO). We therefore studied this clinical question by emulating a randomized trial with observational data.

METHODS

All patients with refractory postcardiotomy cardiogenic shock and assisted with VA-ECMO, admitted to a surgical intensive care unit at La Pitié-Salpêtrière Hospital between 2016 and 2019, were eligible. To avoid immortal-time bias, we emulated a target trial sequentially comparing levosimendan administration versus no levosimendan administration in patients treated with VA-ECMO. The primary outcome was time to successful ECMO weaning. The secondary outcomes were 30-day and 1-year mortality. We performed a multivariable analysis to adjust for confounding at baseline.

RESULTS

Two hundred and thirty-nine patients were included in the study allowing building a nested trials cohort of 1434 copies of patients. No association of levosimendan treatment and VA-ECMO weaning was found (HR = 0.91, [0.57; 1.45], p = 0.659 in multivariable analysis), or 30-day mortality (OR = 1.03, [0.52; 2.03], p = 0.940) and 1-year mortality (OR = 1.00, [0.53; 1.89], p = 0.999).

CONCLUSIONS

Using the emulated target trial framework, this study did not find any association of levosimendan treatment and ECMO weaning success after postcardiotomy cardiogenic shock. However, the population of interest remains heterogeneous and subgroups might benefit from levosimendan.

Comparative outcomes of extracorporeal membrane oxygenation for COVID-19 delivered in experienced European centres during successive SARS-CoV-2 variant outbreaks (ECMO-SURGES): an international, multicentre, retrospective cohort study

BACKGROUND

To inform future research and practice, we aimed to investigate the outcomes of patients who received extracorporeal membrane oxygenation (ECMO) for acute respiratory distress syndrome (ARDS) due to different variants of SARS-CoV-2.

METHODS

This retrospective study included consecutive adult patients with laboratory-confirmed SARS-CoV-2 infection who received ECMO for ARDS in 21 experienced ECMO centres in eight European countries (Austria, Belgium, England, France, Germany, Italy, Portugal, and Spain) between Jan 1, 2020, and Sept 30, 2021. We collected data on patient characteristics, clinical status, and management before and after the initiation of ECMO. Participants were grouped according to SARS-CoV-2 variant (wild type, alpha, delta, or other) and period of the pandemic (first [Jan 1-June 30] and second [July 1-Dec 31] semesters of 2020, and first [Jan 1-June 30] and second [July 1-Sept 30] semesters of 2021). Descriptive statistics and Kaplan-Meier survival curves were used to analyse evolving characteristics, management, and patient outcomes over the first 2 years of the pandemic, and independent risk factors of mortality were determined using multivariable Cox regression models. The primary outcome was mortality 90 days after the initiation of ECMO, with follow-up to Dec 30, 2021.

FINDINGS

ECMO was initiated in 1345 patients. Patient characteristics and management were similar for the groups of patients infected with different variants, except that those with the delta variant had a younger median age and less hypertension and diabetes. 90-day mortality was 42% (569 of 1345 patients died) overall, and 43% (297/686) in patients infected with wild-type SARS-CoV-2, 39% (152/391) in those with the alpha variant, 40% (78/195) in those with the delta variant, and 58% (42/73) in patients infected with other variants (mainly beta and gamma). Mortality was 10% higher (50%) in the second semester of 2020, when the wild-type variant was still prevailing, than in other semesters (40%). Independent predictors of mortality were age, immunocompromised status, a longer time from intensive care unit admission to intubation, need for renal replacement therapy, and higher Sequential Organ Failure Assessment haemodynamic component score, partial pressure of arterial carbon dioxide, and lactate concentration before ECMO. After adjusting for these variables, mortality was significantly higher with the delta variant than with the other variants, the wild-type strain being the reference.

INTERPRETATION

Although crude mortality did not differ between variants, adjusted risk of death was highest for patients treated with ECMO infected with the delta variant of SARS-CoV-2. The higher virulence and poorer outcomes associated with the delta strain might relate to higher viral load and increased inflammatory response syndrome in infected patients, reinforcing the need for a higher rate of vaccination in the population and updated selection criteria for ECMO, should a new and highly virulent strain of SARS-CoV-2 emerge in the future. Mortality was noticeably lower than in other large, multicentre series of patients who received ECMO for COVID-19, highlighting the need to concentrate resources at experienced centres.

FUNDING

None.

Surgery for glioblastomas in the elderly: an Association des Neuro-oncologues d’Expression Française (ANOCEF) trial

OBJECTIVE

The role of surgery in the treatment of malignant gliomas in the elderly is not settled. The authors conducted a randomized trial that compared tumor resection with biopsy only—both followed by standard therapy—in such patients.

METHODS

Patients ≥ 70 years of age with a Karnofsky Performance Scale (KPS) score ≥ 50 and presenting with a radiological suspicion of operable glioblastoma (GBM) were randomly assigned between tumor resection and biopsy groups. Subsequently, they underwent standard radiotherapy during the first years of the trial (2008–2017), with the addition of adjunct therapy with temozolomide when this regimen became standard (2017–2019). The primary endpoint was survival, and secondary endpoints were progression-free survival (PFS), cognitive status (Mini-Mental State Examination), autonomy (KPS), quality of life (European Organisation for Research and Treatment of Cancer [EORTC] QLQ-C30 and QLQ-BN20), and perioperative morbidity and mortality.

RESULTS

Between 2008 and 2019, 107 patients from 9 centers were enrolled in the study; 101 were evaluable for analysis because a GBM was histologically confirmed (50 in the surgery arm and 51 in the biopsy arm). There was no statistically significant difference in median survival between the surgery (9.37 months) and the biopsy (8.96 months, p = 0.36) arms (adjusted HR 0.79, 95% CI 0.52–1.21, p = 0.28). However, the surgery group had an increased PFS (5.06 vs 4.02 months; p = 0.034) (adjusted HR 0.50, 95% CI 0.32–0.78, p = 0.002). Less deterioration of quality of life and KPS score evolution than in the biopsy group was observed. Surgery was not associated with increased mortality or morbidity.

CONCLUSIONS

This study suggests that debulking surgery is safe, and—compared to biopsy—is associated with a less severe deterioration of quality of life and autonomy, as well as a significant although modest improvement of PFS in elderly patients suffering from newly diagnosed malignant glioma. Although resection does not provide a significant survival benefit in the elderly, the authors believe that the risk/benefit analysis favors an attempt at optimal tumor resection in this population, provided there is careful preoperative geriatric evaluation.

Clinical trial registration no.: NCT02892708 (ClinicalTrials.gov)

Extracorporeal Membrane Oxygenation for Severe Acute Respiratory Distress Syndrome Associated with COVID-19: An Emulated Target Trial Analysis

Rationale: Whether patients with coronavirus disease (COVID-19) may benefit from extracorporeal membrane oxygenation (ECMO) compared with conventional invasive mechanical ventilation (IMV) remains unknown. Objectives: To estimate the effect of ECMO on 90-day mortality versus IMV only. Methods: Among 4,244 critically ill adult patients with COVID-19 included in a multicenter cohort study, we emulated a target trial comparing the treatment strategies of initiating ECMO versus no ECMO within 7 days of IMV in patients with severe acute respiratory distress syndrome (PaO2/FiO2 < 80 or PaCO2 ⩾ 60 mm Hg). We controlled for confounding using a multivariable Cox model on the basis of predefined variables. Measurements and Main Results: A total of 1,235 patients met the full eligibility criteria for the emulated trial, among whom 164 patients initiated ECMO. The ECMO strategy had a higher survival probability on Day 7 from the onset of eligibility criteria (87% vs. 83%; risk difference, 4%; 95% confidence interval, 0-9%), which decreased during follow-up (survival on Day 90: 63% vs. 65%; risk difference, -2%; 95% confidence interval, -10 to 5%). However, ECMO was associated with higher survival when performed in high-volume ECMO centers or in regions where a specific ECMO network organization was set up to handle high demand and when initiated within the first 4 days of IMV and in patients who are profoundly hypoxemic. Conclusions: In an emulated trial on the basis of a nationwide COVID-19 cohort, we found differential survival over time of an ECMO compared with a no-ECMO strategy. However, ECMO was consistently associated with better outcomes when performed in high-volume centers and regions with ECMO capacities specifically organized to handle high demand.

Impact of Anti-tumour Necrosis Factor Agents on the Risk of Colorectal Cancer in Patients with Ulcerative Colitis: Nationwide French Cohort Study

BACKGROUND AND AIMS

Patients with ulcerative colitis [UC] are at increased risk of colorectal cancer. Anti-tumour necrosis factor agents [anti-TNF] aim to reduce chronic colonic inflammation and may lower the risk of colorectal cancer [CRC], but the impact of anti-TNF exposure has not yet been assessed in population-based cohort studies. The aim of this nationwide study was to assess the risk of CRC in patients with UC exposed to anti-TNF.

METHODS

Based on the French health insurance database, patients aged 18 years or older with a diagnosis of UC, previously exposed to or initiating immunosuppressive treatment, were followed from January 1, 2009, until December 31, 2018. The risk of CRC associated with anti-TNF exposure was assessed using marginal structural Cox proportional hazard models adjusting for baseline and time-varying comorbidities including primary sclerosing cholangitis, UC disease activity, colonoscopic surveillance, and other medications.

RESULTS

Among 32 403 patients with UC, 15 542 [48.0%] were exposed to anti-TNF. During a median follow-up of 6.1 years [198 249 person-years], 246 incident CRC occurred (incidence rate per 1000 person-years, 1.24; 95% confidence intrval [CI], 1.10-1.41). Whereas the risk of CRC associated with anti-TNF exposure was not decreased in the overall group of patients with UC (hazard ratio [HR], 0.85; 95% CI, 0.58-1.26), anti-TNF exposure was associated with a decreased risk of CRC in patients with long-standing colitis [disease duration ≥10 years] [HR, 0.41; 95% CI, 0.20-0.86].

CONCLUSIONS

In a nationwide cohort of patients with UC, anti-TNF exposure was associated with a decreased risk of CRC in patients with long-standing colitis.

Positive impact on 10-year outcome of the window of opportunity for conventional synthetic DMARDs in rheumatoid arthritis: results from the ESPOIR cohort

Objective

This study aimed to assess the impact of disease-modifying antirheumatic drugs (DMARDs) on 10-year outcomes in rheumatoid arthritis (RA).

Methods

Patients with RA from the ESPOIR cohort with complete data on Disease Activity Score in 28 Joints (DAS28) and Health Assessment Questionnaire (HAQ) at 10 years (n=418) and complete radiographic data at baseline and 10 years (n=343) were included in this study. Outcomes were favourable outcome (FavOut) at 10 years, defined as DAS28 of <2.6 and HAQ score of <0.5 at 10 years, and absence of structural damage progression (AbsSDP) at 10 years, defined as change in Sharp-van der Heijde Score less than the smallest detectable change at 10 years (11.5 points). Three multivariate logistic regression models predicting 10-year outcome were built, considering (1) baseline variables only, (2) baseline variables and DMARD exposure (ever exposed, yes/no) and (3) baseline variables and DMARD exposure as weighted cumulative exposure (WCE) variables.

Results

Overall, 196/418 (46.9%) patients showed FavOut and 252/343 (73.5%) AbsSDP. WCE models had the best predictive performance, with area under the curve=0.80 (95% CI 0.74 to 0.87) for FavOut and 0.87 (95% CI 0.83 to 0.92) for AbsSDP. In the WCE model, the odds of FavOut and AbsSDP were reduced with conventional synthetic disease-modifying antirheumatic drug (csDMARD) initiation at 12 months versus at baseline (OR 0.78, 95% CI 0.65 to 0.94, and OR 0.89, 95% CI 0.76 to 0.98, respectively). Early biologics initiation was not significantly associated with either outcome.

Conclusions

WCE models can identify and quantify the long-term benefit of early csDMARD initiation on 10-year functional and structural outcomes in patients with RA.

Cumulative incidence of SARS-CoV-2 infection and associated risk factors among frontline health care workers in Paris: the SEROCOV cohort study

With the COVID-19 pandemic, documenting whether health care workers (HCWs) are at increased risk of SARS-CoV-2 contamination and identifying risk factors is of major concern. In this multicenter prospective cohort study, HCWs from frontline departments were included in March and April 2020 and followed for 3 months. SARS-CoV-2 serology was performed at month 0 (M0), M1, and M3 and RT-PCR in case of symptoms. The primary outcome was laboratory-confirmed SARS-CoV-2 infection at M3. Risk factors of laboratory-confirmed SARS-CoV-2 infection at M3 were identified by multivariate logistic regression. Among 1062 HCWs (median [interquartile range] age, 33 [28–42] years; 758 [71.4%] women; 321 [30.2%] physicians), the cumulative incidence of SARS-CoV-2 infection at M3 was 14.6% (95% confidence interval [CI] [12.5; 16.9]). Risk factors were the working department specialty, with increased risk for intensive care units (odds ratio 1.80, 95% CI [0.38; 8.58]), emergency departments (3.91 [0.83; 18.43]) and infectious diseases departments (4.22 [0.92; 18.28]); current smoking was associated with reduced risk (0.36 [0.21; 0.63]). Age, sex, professional category, number of years of experience in the job or department, and public transportation use were not significantly associated with laboratory-confirmed SARS-CoV-2 infection at M3. The rate of SARS-CoV-2 infection in frontline HCWs was 14.6% at the end of the first COVID-19 wave in Paris and occurred mainly early. The study argues for an origin of professional in addition to private life contamination and therefore including HCWs in the first-line vaccination target population. It also highlights that smokers were at lower risk.

Trial registration The study has been registered on ClinicalTrials.gov: NCT04304690 first registered on 11/03/2020.

Early prone positioning in acute respiratory distress syndrome related to COVID-19: a propensity score analysis from the multicentric cohort COVID-ICU network-the ProneCOVID study

Background

Delaying time to prone positioning (PP) may be associated with higher mortality in acute respiratory distress syndrome (ARDS) due to coronavirus disease 2019 (COVID-19). We evaluated the use and the impact of early PP on clinical outcomes in intubated patients hospitalized in intensive care units (ICUs) for COVID-19.

Methods

All intubated patients with ARDS due to COVID-19 were involved in a secondary analysis from a prospective multicenter cohort study of COVID-ICU network including 149 ICUs across France, Belgium and Switzerland. Patients were followed-up until Day-90. The primary outcome was survival at Day-60. Analysis used a Cox proportional hazard model including a propensity score.

Results

Among 2137 intubated patients, 1504 (70.4%) were placed in PP during their ICU stay and 491 (23%) during the first 24 h following ICU admission. One hundred and eighty-one patients (36.9%) of the early PP group had a PaO₂/FiO₂ ratio > 150 mmHg when prone positioning was initiated. Among non-early PP group patients, 1013 (47.4%) patients had finally been placed in PP within a median delay of 3 days after ICU admission. Day-60 mortality in non-early PP group was 34.2% versus 39.3% in the early PP group (p = 0.038). Day-28 and Day-90 mortality as well as the need for adjunctive therapies was more important in patients with early PP. After propensity score adjustment, no significant difference in survival at Day-60 was found between the two study groups (HR 1.34 [0.96–1.68], p = 0.09 and HR 1.19 [0.998–1.412], p = 0.053 in complete case analysis or in multiple imputation analysis, respectively).

Conclusions

In a large multicentric international cohort of intubated ICU patients with ARDS due to COVID-19, PP has been used frequently as a main treatment. In this study, our data failed to show a survival benefit associated with early PP started within 24 h after ICU admission compared to PP after day-1 for all COVID-19 patients requiring invasive mechanical ventilation regardless of their severity.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-022-03949-7.

Personalization of renal replacement therapy initiation: a secondary analysis of the AKIKI and IDEAL-ICU trials

Background

Trials comparing early and delayed strategies of renal replacement therapy in patients with severe acute kidney injury may have missed differences in survival as a result of mixing together patients at heterogeneous levels of risks. Our aim was to evaluate the heterogeneity of treatment effect on 60-day mortality from an early vs a delayed strategy across levels of risk for renal replacement therapy initiation under a delayed strategy.

Methods

We used data from the AKIKI, and IDEAL-ICU randomized controlled trials to develop a multivariable logistic regression model for renal replacement therapy initiation within 48 h after allocation to a delayed strategy. We then used an interaction with spline terms in a Cox model to estimate treatment effects across the predicted risks of RRT initiation.

Results

We analyzed data from 1107 patients (619 and 488 in the AKIKI and IDEAL-ICU trial respectively). In the pooled sample, we found evidence for heterogeneous treatment effects (P = 0.023). Patients at an intermediate-high risk of renal replacement therapy initiation within 48 h may have benefited from an early strategy (absolute risk difference, − 14%; 95% confidence interval, − 27% to − 1%). For other patients, we found no evidence of benefit from an early strategy of renal replacement therapy initiation but a trend for harm (absolute risk difference, 8%; 95% confidence interval, − 5% to 21% in patients at intermediate-low risk).

Conclusions

We have identified a clinically sound heterogeneity of treatment effect of an early vs a delayed strategy of renal replacement therapy initiation that may reflect varying degrees of kidney demand-capacity mismatch.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-022-03936-y.

Effect of prone positioning on survival in adult patients receiving venovenous extracorporeal membrane oxygenation for acute respiratory distress syndrome: a systematic review and meta-analysis

Purpose

Previous studies support the potential efficacy of venovenous extracorporeal membrane oxygenation (vvECMO) for improving survival in severe acute respiratory distress syndrome (ARDS) cases. Prone positioning (PP) has been shown to improve the outcomes of moderate-to-severe ARDS patients. Few studies and no randomized controlled trials have evaluated the effect of PP performed in ECMO patients.

Methods

We performed a systematic review and meta-analysis examining the effect of prone positioning for ARDS patients receiving vvECMO on survival. All authors were contacted to obtain complementary information not mentioned in the original articles. The main objective was to compare 28-day survival in vvECMO patients with PP to vvECMO patients without PP (controls).

Results

Thirteen studies with a combined population of 1836 patients satisfied the inclusion criteria. PP was associated with a significant improvement in 28-day survival (503 survivors among 681 patients in the PP group [74%; 95% CI 71–77] vs. 450 survivors among 770 patients in the control group [58%, 95% CI 55–62]; RR 1.31 [95% CI 1.21–1.41]; I² 22% [95% CI 0–62%]; P < 0.0001). Survival was also improved in terms of other endpoints (60-day survival, 90-day survival, ICU survival, and hospital survival). In contrast, the duration of mechanical ventilation was increased in vvECMO patients with PP (mean difference 11.4 days [95% CI 9.2–13.5]; 0.64 [95% CI 0.50–0.78]; I² 8%; P < 0.0001).

Conclusion

According to this meta-analysis, survival was improved when prone positioning was used in ARDS patients receiving vvECMO. The impact of this combination on survival should be investigated in prospective randomized controlled trials.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00134-021-06604-x.

Predicting 90-day survival of patients with COVID-19: Survival of Severely Ill COVID (SOSIC) scores

BACKGROUND

Predicting outcomes of critically ill intensive care unit (ICU) patients with coronavirus-19 disease (COVID-19) is a major challenge to avoid futile, and prolonged ICU stays.

METHODS

The objective was to develop predictive survival models for patients with COVID-19 after 1-to-2 weeks in ICU. Based on the COVID-ICU cohort, which prospectively collected characteristics, management, and outcomes of critically ill patients with COVID-19. Machine learning was used to develop dynamic, clinically useful models able to predict 90-day mortality using ICU data collected on day (D) 1, D7 or D14.

RESULTS

Survival of Severely Ill COVID (SOSIC)-1, SOSIC-7, and SOSIC-14 scores were constructed with 4244, 2877, and 1349 patients, respectively, randomly assigned to development or test datasets. The three models selected 15 ICU-entry variables recorded on D1, D7, or D14. Cardiovascular, renal, and pulmonary functions on prediction D7 or D14 were among the most heavily weighted inputs for both models. For the test dataset, SOSIC-7's area under the ROC curve was slightly higher (0.80 [0.74-0.86]) than those for SOSIC-1 (0.76 [0.71-0.81]) and SOSIC-14 (0.76 [0.68-0.83]). Similarly, SOSIC-1 and SOSIC-7 had excellent calibration curves, with similar Brier scores for the three models.

CONCLUSION

The SOSIC scores showed that entering 15 to 27 baseline and dynamic clinical parameters into an automatable XGBoost algorithm can potentially accurately predict the likely 90-day mortality post-ICU admission (sosic.shinyapps.io/shiny). Although external SOSIC-score validation is still needed, it is an additional tool to strengthen decisions about life-sustaining treatments and informing family members of likely prognosis.

Efficacy of Acyclovir to Suppress Herpes Simplex Virus Oropharyngeal Reactivation in Patients Who Are Mechanically Ventilated: An Ancillary Study of the Preemptive Treatment for Herpesviridae (PTH) Trial

This analysis of a randomized clinical trial examines the efficacy of acyclovir for preventing oropharyngeal HSV reactivation among patients who were mechanically ventilated.

Fully automated opportunistic screening of vertebral fractures and osteoporosis on more than 150,000 routine computed tomography scans

OBJECTIVE

Osteoporosis is underdiagnosed and undertreated, although severe complications of osteoporotic fractures, including vertebral fractures, are well known. This study sought to assess the feasibility and results of an opportunistic screening of vertebral fractures and osteoporosis in a large database of lumbar or abdominal CT scans.

MATERIAL AND METHODS

Data were analyzed from CT scans obtained in 35 hospitals from patients aged 60 years and more and stored in a Picture Archiving and Communication System in Assistance-Publique-Hôpitaux de Paris, from 2007 to 2013. Dedicated software analyzed the presence of at least 1 vertebral fracture (VF), and measured Hounsfield Units (HU) in lumbar vertebrae. A simulated T-score was calculated.

RESULTS

Data were analyzed from 152 268 patients (73.2 ± 9.07 years). Success rates for VF assessment and HU measurements were 82 and 87% respectively. Prevalence of VF was 24.5% and increased with age. Areas under the receiver operating characteristic curves for the detection of VF were 0.61 and 0.62 for mean HU of lumbar vertebrae and L1 HU, respectively. In patients without VF, HU decreased with age, similarly in males and females. The prevalence of osteoporosis (sT-score ≤ - 2.5) was 23.8% and 36.5% in patients without and with VFs respectively.

CONCLUSION

Opportunistic screening in patients 60 years and older having lumbar or abdominal CT scans is feasible at large scale to screen vertebral fractures and osteoporosis.

Evolving outcomes of extracorporeal membrane oxygenation support for severe COVID-19 ARDS in Sorbonne hospitals, Paris

Background

Extracorporeal membrane oxygenation (ECMO) was frequently used to treat patients with severe coronavirus disease-2019 (COVID-19)-associated acute respiratory distress (ARDS) during the initial outbreak. Care of COVID-19 patients evolved markedly during the second part of 2020. Our objective was to compare the characteristics and outcomes of patients who received ECMO for severe COVID-19 ARDS before or after July 1, 2020.

Methods

We included consecutive adults diagnosed with COVID-19 in Paris–Sorbonne University Hospital Network ICUs, who received ECMO for severe ARDS until January 28, 2021. Characteristics and survival probabilities over time were estimated during the first and second waves. Pre-ECMO risk factors predicting 90-day mortality were assessed using multivariate Cox regression.

Results

Characteristics of the 88 and 71 patients admitted, respectively, before and after July 1, 2020, were comparable except for older age, more frequent use of dexamethasone (18% vs. 82%), high-flow nasal oxygenation (19% vs. 82%) and/or non-invasive ventilation (7% vs. 37%) after July 1. Respective estimated probabilities (95% confidence intervals) of 90-day mortality were 36% (27–47%) and 48% (37–60%) during the first and the second periods. After adjusting for confounders, probability of 90-day mortality was significantly higher for patients treated after July 1 (HR 2.27, 95% CI 1.02–5.07). ECMO-related complications did not differ between study periods.

Conclusions

90-day mortality of ECMO-supported COVID-19–ARDS patients increased significantly after July 1, 2020, and was no longer comparable to that of non-COVID ECMO-treated patients. Failure of prolonged non-invasive oxygenation strategies before intubation and increased lung damage may partly explain this outcome.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-021-03780-6.

Association Between Lack of Blinding and Mortality Results in Critical Care Randomized Controlled Trials: A Meta-Epidemiological Study

OBJECTIVES

To investigate whether intervention effect estimates for mortality differ between blinded and nonblinded randomized controlled trials conducted in critical care. We used a meta-epidemiological approach, comparing effect estimates between blinded and nonblinded randomized controlled trials for the same research question.

DATA SOURCES

Systematic reviews and meta-analyses of randomized controlled trials evaluating a therapeutic intervention on mortality in critical care, published between January 2009 and March 2019 in high impact factor general medical or critical care journals and by Cochrane.

DATA EXTRACTION

For each randomized controlled trial included in eligible meta-analyses, we evaluated whether the trial was blinded (i.e., double-blinded and/or reporting adequate methods) or not (i.e., open-label, single-blinded, or unclear). We collected risk of bias evaluated by the review authors and extracted trial results.

DATA SYNTHESIS

Within each meta-analysis, we compared intervention effect estimates between blinded and nonblinded randomized controlled trials by using a ratio of odds ratio (< 1 indicates larger estimates in nonblinded than blinded randomized controlled trials). We then combined ratio of odds ratios across meta-analyses to obtain the average relative difference between nonblinded and blinded trials. Among 467 randomized controlled trials included in 36 meta-analyses, 267 (57%) were considered blinded and 200 (43%) nonblinded. Intervention effect estimates were statistically significantly larger in nonblinded than blinded trials (combined ratio of odds ratio, 0.91; 95% CI, 0.84-0.99). We found no heterogeneity across meta-analyses (p = 0.72; I2 = 0%; τ2 = 0). Sensitivity analyses adjusting the main analysis on risk of bias items yielded consistent results.

CONCLUSIONS

Intervention effect estimates of mortality were slightly larger in nonblinded than blinded randomized controlled trials conducted in critical care, but confounding cannot be excluded. Blinding of both patients and personnel is important to consider when possible in critical care trials, even when evaluating mortality.

PL03.1.A Surgery for glioblastomas in the elderly: an ANOCEF trial (CSA)

BACKGROUND

The role of surgery for the treatment of malignant gliomas in patients 70 years of age or older is unsettled. We conducted a randomized trial that compared surgical resection of the tumor and biopsy only, both followed by standard therapy, in such patients.

MATERIAL AND METHODS

Patients aged 70 years and older, with a KPS of at least 50, presenting with a radiological suspicion of an operable glioblastoma (GBM) were randomly assigned between tumor resection and biopsy. Subsequently, they underwent standard radiotherapy during the first years of the trial (2008–2017), with the adjunction of concomitant and adjuvant temozolomide when this regimen became standard (2017–2019). The primary end point was survival; secondary endpoints were progression free survival (PFS), cognitive status (MMS), autonomy (KPS), quality of life (EORTC QLQ C30 and BN20), and perioperative morbidity/ mortality.

RESULTS

From 2008 to 2019, 107 patients from 9 centers were enrolled in the study, of whom 101 were evaluable for analysis because the diagnosis of GBM was histologically confirmed (50 patients in the “surgery” arm and 51 patients in the “biopsy” arm). There was no statistically significant difference of median survival between the “surgery” arm (9.37 mo) and the “biopsy” arms (8.96 mo, p=0.36). However, the surgery group had increased PFS (5.06 mo vs 4.02 mo; p=0.034; p=0.002 on multivariate analysis) and better QOL (e.g. physical and cognitive functioning, motor dysfunction, fatigue) and KPS score evolution as compared to the “biopsy” group. Surgery was not associated with increased mortality or morbidity.

CONCLUSION

This study suggests that optimal debulking surgery does not provide a significant survival benefit in elderly patients suffering from newly diagnosed malignant glioma, but resection improves QOL and autonomy with a significant though modest improvement of PFS.

Variance estimators for weighted and stratified linear dose-response function estimators using generalized propensity score

Propensity score methods are widely used in observational studies for evaluating marginal treatment effects. The generalized propensity score (GPS) is an extension of the propensity score framework, historically developed in the case of binary exposures, for use with quantitative or continuous exposures. In this paper, we proposed variance estimators for treatment effect estimators on continuous outcomes. Dose-response functions (DRFs) were estimated through weighting on the inverse of the GPS, or using stratification. Variance estimators were evaluated using Monte Carlo simulations. Despite the use of stabilized weights, the variability of the weighted estimator of the DRF was particularly high, and none of the variance estimators (a bootstrap-based estimator, a closed-form estimator especially developed to take into account the estimation step of the GPS, and a sandwich estimator) were able to adequately capture this variability, resulting in coverages below the nominal value, particularly when the proportion of the variation in the quantitative exposure explained by the covariates was large. The stratified estimator was more stable, and variance estimators (a bootstrap-based estimator, a pooled linearized estimator, and a pooled model-based estimator) more efficient at capturing the empirical variability of the parameters of the DRF. The pooled variance estimators tended to overestimate the variance, whereas the bootstrap estimator, which intrinsically takes into account the estimation step of the GPS, resulted in correct variance estimations and coverage rates. These methods were applied to a real data set with the aim of assessing the effect of maternal body mass index on newborn birth weight.

Characteristics, management, and prognosis of elderly patients with COVID-19 admitted in the ICU during the first wave: insights from the COVID-ICU study : Prognosis of COVID-19 elderly critically ill patients in the ICU

Background

The COVID-19 pandemic is a heavy burden in terms of health care resources. Future decision-making policies require consistent data on the management and prognosis of the older patients (> 70 years old) with COVID-19 admitted in the intensive care unit (ICU).

Methods

Characteristics, management, and prognosis of critically ill old patients (> 70 years) were extracted from the international prospective COVID-ICU database. A propensity score weighted-comparison evaluated the impact of intubation upon admission on Day-90 mortality.

Results

The analysis included 1199 (28% of the COVID-ICU cohort) patients (median [interquartile] age 74 [72–78] years). Fifty-three percent, 31%, and 16% were 70–74, 75–79, and over 80 years old, respectively. The most frequent comorbidities were chronic hypertension (62%), diabetes (30%), and chronic respiratory disease (25%). Median Clinical Frailty Scale was 3 (2–3). Upon admission, the PaO₂/FiO₂ ratio was 154 (105–222). 740 (62%) patients were intubated on Day-1 and eventually 938 (78%) during their ICU stay. Overall Day-90 mortality was 46% and reached 67% among the 193 patients over 80 years old. Mortality was higher in older patients, diabetics, and those with a lower PaO₂/FiO₂ ratio upon admission, cardiovascular dysfunction, and a shorter time between first symptoms and ICU admission. In propensity analysis, early intubation at ICU admission was associated with a significantly higher Day-90 mortality (42% vs 28%; hazard ratio 1.68; 95% CI 1.24–2.27; p < 0·001).

Conclusion

Patients over 70 years old represented more than a quarter of the COVID-19 population admitted in the participating ICUs during the first wave. Day-90 mortality was 46%, with dismal outcomes reported for patients older than 80 years or those intubated upon ICU admission.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13613-021-00861-1.

Vascular access for renal replacement therapy among 459 critically ill patients: a pragmatic analysis of the randomized AKIKI trial

BACKGROUND

Vascular access for renal replacement therapy (RRT) is routine question in the intensive care unit. Randomized trials comparing jugular and femoral sites have shown similar rate of nosocomial events and catheter dysfunction. However, recent prospective observational data on RRT catheters use are scarce. We aimed to assess the site of RRT catheter, the reasons for catheter replacement, and the complications according to site in a large population of critically ill patients with acute kidney injury.

PATIENTS AND METHODS

We performed an ancillary study of the AKIKI study, a pragmatic randomized controlled trial, in which patients with severe acute kidney injury (KDIGO 3 classification) with invasive mechanical ventilation, catecholamine infusion or both were randomly assigned to either an early or a delayed RRT initiation strategy. The present study involved all patients who underwent at least one RRT session. Number of RRT catheters, insertion sites, factors potentially associated with the choice of insertion site, duration of catheter use, reason for catheter replacement, and complications were prospectively collected.

RESULTS

Among the 619 patients included in AKIKI, 462 received RRT and 459 were finally included, with 598 RRT catheters. Femoral site was chosen preferentially (n = 319, 53%), followed by jugular (n = 256, 43%) and subclavian (n = 23, 4%). In multivariate analysis, continuous RRT modality was significantly associated with femoral site (OR = 2.33 (95% CI (1.34-4.07), p = 0.003) and higher weight with jugular site [88.9 vs 83.2 kg, OR = 0.99 (95% CI 0.98-1.00), p = 0.03]. Investigator site was also significantly associated with the choice of insertion site (p = 0.03). Cumulative incidence of catheter replacement did not differ between jugular and femoral site [sHR 0.90 (95% CI 0.64-1.25), p = 0.67]. Catheter dysfunction was the main reason for replacement (n = 47), followed by suspected infection (n = 29) which was actually seldom proven (n = 4). No mechanical complication (pneumothorax or hemothorax) occurred.

CONCLUSION

Femoral site was preferentially used in this prospective study of RRT catheters in 31 French intensive care units. The choice of insertion site depended on investigating center habits, weight, RRT modality. A high incidence of catheter infection suspicion led to undue replacement.

Comparison of two delayed strategies for renal replacement therapy initiation for severe acute kidney injury (AKIKI 2): a multicentre, open-label, randomised, controlled trial

BACKGROUND

Delaying renal replacement therapy (RRT) for some time in critically ill patients with severe acute kidney injury and no severe complication is safe and allows optimisation of the use of medical devices. Major uncertainty remains concerning the duration for which RRT can be postponed without risk. Our aim was to test the hypothesis that a more-delayed initiation strategy would result in more RRT-free days, compared with a delayed strategy.

METHODS

This was an unmasked, multicentre, prospective, open-label, randomised, controlled trial done in 39 intensive care units in France. We monitored critically ill patients with severe acute kidney injury (defined as Kidney Disease: Improving Global Outcomes stage 3) until they had oliguria for more than 72 h or a blood urea nitrogen concentration higher than 112 mg/dL. Patients were then randomly assigned (1:1) to either a strategy (delayed strategy) in which RRT was started just after randomisation or to a more-delayed strategy. With the more-delayed strategy, RRT initiation was postponed until mandatory indication (noticeable hyperkalaemia or metabolic acidosis or pulmonary oedema) or until blood urea nitrogen concentration reached 140 mg/dL. The primary outcome was the number of days alive and free of RRT between randomisation and day 28 and was done in the intention-to-treat population. The study is registered with ClinicalTrial.gov, NCT03396757 and is completed.

FINDINGS

Between May 7, 2018, and Oct 11, 2019, of 5336 patients assessed, 278 patients underwent randomisation; 137 were assigned to the delayed strategy and 141 to the more-delayed strategy. The number of complications potentially related to acute kidney injury or to RRT were similar between groups. The median number of RRT-free days was 12 days (IQR 0-25) in the delayed strategy and 10 days (IQR 0-24) in the more-delayed strategy (p=0·93). In a multivariable analysis, the hazard ratio for death at 60 days was 1·65 (95% CI 1·09-2·50, p=0·018) with the more-delayed versus the delayed strategy. The number of complications potentially related to acute kidney injury or renal replacement therapy did not differ between groups.

INTERPRETATION

In severe acute kidney injury patients with oliguria for more than 72 h or blood urea nitrogen concentration higher than 112 mg/dL and no severe complication that would mandate immediate RRT, longer postponing of RRT initiation did not confer additional benefit and was associated with potential harm.

FUNDING

Programme Hospitalier de Recherche Clinique.

Relative Contribution of Gestational Weight Gain, Gestational Diabetes, and Maternal Obesity to Neonatal Fat Mass

Maternal nutritional and metabolic status influence fetal growth. This study investigated the contribution of gestational weight gain (GWG), gestational diabetes (GDM), and maternal obesity to birthweight and newborn body fat. It is a secondary analysis of a prospective study including 204 women with a pregestational body mass index (BMI) of 18.5-24.9 kg/m² and 219 women with BMI ≥ 30 kg/m². GDM was screened in the second and third trimester and was treated by dietary intervention, and insulin if required. Maternal obesity had the greatest effect on skinfolds (+1.4 mm) and cord leptin (+3.5 ng/mL), but no effect on birthweight. GWG was associated with increased birthweight and skinfolds thickness, independently from GDM and maternal obesity. There was an interaction between third trimester weight gain and GDM on birthweight and cord leptin, but not with maternal obesity. On average, +1 kg in third trimester was associated with +13 g in birthweight and with +0.64 ng/mL in cord leptin, and a further 32 g and 0.89 ng/mL increase in diabetic mothers, respectively. Maternal obesity is the main contributor to neonatal body fat. There is an independent association between third trimester weight gain, birthweight, and neonatal body fat, enhanced by GDM despite intensive treatment.

Baclofen destabilises breathing during sleep in healthy humans: A randomised, controlled, double-blind crossover trial

AIMS

Periodic breathing is frequent in patients with severe heart failure. Apart from being an indicator of severity, periodic breathing has its own deleterious consequences (sleep-related oxygen desaturations, sleep fragmentation), which justifies attempts to correct it irrespective of the underlying disease. Animal models and human data suggest that baclofen can reconfigure respiratory central pattern generators. We hypothesised that baclofen, a GABA_B agonist, may thus be able to correct periodic breathing in humans.

METHODS

Healthy volunteers were exposed to hypoxia during sleep. Participants who developed periodic breathing (n = 14 [53 screened]) were randomly assigned to double-blind oral baclofen (progressively increased to 60 mg/d) or placebo. The primary outcome was the coefficient of variation (CoVar) of respiratory cycle total time considered as an indicator of breathing irregularity. Secondary outcomes included the CoVar of tidal volume, apnoea-hypopnoea index, sleep fragmentation index and ventilatory complexity (noise limit).

RESULTS

The analysis was conducted in 9 subjects after exclusion of incomplete datasets. CoVar of respiratory cycle total time significantly increased with baclofen during non-rapid eye movement sleep (median with placebo 56.00% [37.63-78.95]; baclofen 85.42% [68.37-86.40], P = .020; significant difference during the N1-N2 phases of sleep but not during the N3 phase). CoVar of tidal volume significantly increased during N1-N2 sleep. The apnoea-hypopnoea index, sleep fragmentation index and ventilatory complexity were not significantly different between placebo and baclofen.

CONCLUSION

Baclofen did not stabilise breathing in our model. On the contrary, it increased respiratory variability. Baclofen should probably not be used in patients with or at risk of periodic breathing.

Respiratory support in COPD patients after acute exacerbation with monitoring the quality of support (Rescue2-monitor): an open-label, prospective randomized, controlled, superiority clinical trial comparing hospital- versus home-based acute non-invasive ventilation for patients with hypercapnic chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is expected to be the 3rd leading cause of death worldwide by 2020. Despite improvements in survival by using acute non-invasive ventilation (NIV) to treat patients with exacerbations of COPD complicated by acute hypercapnic respiratory failure (AHRF), these patients are at high risk of readmission and further life-threatening events, including death. Recent studies suggested that NIV at home can reduce readmissions, but in a small proportion of patients, and with a high level of expertise. Other studies, however, do not show any benefit of home NIV. This could be related to the fact that respiratory failure in patients with stable COPD and their response to mechanical ventilation are influenced by several pathophysiological factors which frequently coexist in the same patient to varying degrees. These pathophysiological factors might influence the success of home NIV in stable COPD, thus long-term NIV specifically adapted to a patient's "phenotype" is likely to improve prognosis, reduce readmission to hospital, and prevent death. In view of this conundrum, Rescue2-monitor (R2M), an open-label, prospective randomized, controlled study performed in patients with hypercapnic COPD post-AHRF, will investigate the impact of the quality of nocturnal NIV on the readmission-free survival. The primary objective is to show that any of 3 home NIV strategies ("rescue," "non-targeted," and "targeted") will improve readmission-free survival in comparison to no-home NIV. The "targeted" group of patients will receive a treatment with personalized (targeted) ventilation settings and extensive monitoring. Furthermore, the influence of comorbidities typical for COPD patients, such as cardiac insufficiency, OSA, or associated asthma, on ventilation outcomes will be taken into consideration and reasons for non-inclusion of patients will be recorded in order to evaluate the percentage of ventilated COPD patients that are screening failures. ClinicalTrials.gov NCT03890224 . Registered on March 26, 2019.

ECMO for severe ARDS: systematic review and individual patient data meta-analysis

PURPOSE

To assess the effect of venovenous extracorporeal membrane oxygenation (ECMO) compared to conventional management in patients with severe acute respiratory distress syndrome (ARDS).

METHODS

We conducted a systematic review and individual patient data meta-analysis of randomised controlled trials (RCTs) performed after Jan 1, 2000 comparing ECMO to conventional management in patients with severe ARDS. The primary outcome was 90-day mortality. Primary analysis was by intent-to-treat.

RESULTS

We identified two RCTs (CESAR and EOLIA) and combined data from 429 patients. On day 90, 77 of the 214 (36%) ECMO-group and 103 of the 215 (48%) control group patients had died (relative risk (RR), 0.75, 95% confidence interval (CI) 0.6-0.94; P = 0.013; I² = 0%). In the per-protocol and as-treated analyses the RRs were 0.75 (95% CI 0.6-0.94) and 0.86 (95% CI 0.68-1.09), respectively. Rescue ECMO was used for 36 (17%) of the 215 control patients (35 in EOLIA and 1 in CESAR). The RR of 90-day treatment failure, defined as death for the ECMO-group and death or crossover to ECMO for the control group was 0.65 (95% CI 0.52-0.8; I² = 0%). Patients randomised to ECMO had more days alive out of the ICU and without respiratory, cardiovascular, renal and neurological failure. The only significant treatment-covariate interaction in subgroups was lower mortality with ECMO in patients with two or less organs failing at randomization.

CONCLUSIONS

In this meta-analysis of individual patient data in severe ARDS, 90-day mortality was significantly lowered by ECMO compared with conventional management.

Impact of Point-of-care Testing on Length of Stay of Patients in the Emergency Department: A Cluster-randomized Controlled Study

OBJECTIVES

Crowding is a frequent concern in the emergency department (ED). Laboratory point-of-care testing (POCT) has been proposed to decrease patients' length of stay (LOS). Our objective was to determine whether an extended panel of POCT solutions could reduce LOS.

METHODS

This was a single-center, prospective, open-label, controlled cluster-randomized study. Blood test processing was randomized into 1-week inclusion periods: interventional arm (laboratory analyses performed on POCT analyzers implemented in the ED) or control arm (central laboratory). The primary endpoint was LOS of patients in the ED. Secondary endpoints were time to result (TTR), ED crowding surrogates, and average total cost of an ED visit in each arm.

RESULTS

A total of 23,231 patients were included and 20,923 were analyzed for the main outcome measure. Mean ± SD age was 46 ± 20 years, and 7,905 (36%) underwent blood sampling. Mean ± SD LOSs were 203 ± 161 and 210 ± 168 minutes in the POCT and control arms, respectively. LOS reduction for the entire ED population was -9 minutes (95% confidence interval [CI] = -22 to 5, p = 0.22) compared to the control arm and -17 minutes (95% CI = -34.0 to 0.6, p = 0.06) for patients undergoing blood sampling. The mean ± SD TTRs were 28 ± 31 and 79 ± 34 minutes in the POCT and control arms, respectively (TTR reduction = -51 minutes, 95% CI = -54 to -48 minutes, p < 0.001).

CONCLUSIONS

The implementation of an extended panel of POCT solutions in an ED did not significantly reduce the LOS, but reduced the TTR.

Circulating Receptor Activator of Nuclear Factor kB Ligand and triglycerides are associated with progression of lower limb arterial calcification in type 2 diabetes: a prospective, observational cohort study

Background

Lower limb arterial calcification is a frequent, underestimated but serious complication of diabetes. The DIACART study is a prospective cohort study designed to evaluate the determinants of the progression of lower limb arterial calcification in 198 patients with type 2 diabetes.

Methods

Lower limb arterial calcification scores were determined by computed tomography at baseline and after a mean follow up of 31.20 ± 3.86 months. Serum RANKL (Receptor Activator of Nuclear factor kB Ligand) and bone remodeling, inflammatory and metabolic parameters were measured at baseline. The predictive effect of these markers on calcification progression was analyzed by a multivariate linear regression model.

Results

At baseline, mean ± SD and median lower limb arterial calcification scores were, 2364 ± 5613 and 527 respectively and at the end of the study, 3739 ± 6886 and 1355 respectively. Using multivariate analysis, the progression of lower limb arterial log calcification score was found to be associated with (β coefficient [slope], 95% CI, p-value) baseline log(calcification score) (1.02, 1.00–1.04, p < 0.001), triglycerides (0.11, 0.03–0.20, p = 0.007), log(RANKL) (0.07, 0.02–0.11, p = 0.016), previous ischemic cardiomyopathy (0.36, 0.15–0.57, p = 0.001), statin use (0.39, 0.06–0.72, p = 0.023) and duration of follow up (0.04, 0.01–0.06, p = 0.004).

Conclusion

In patients with type 2 diabetes, lower limb arterial calcification is frequent and can progress rapidly. Circulating RANKL and triglycerides are independently associated with this progression. These results open new therapeutic perspectives in peripheral diabetic calcifying arteriopathy.

Trial registration NCT02431234

Venoarterial extracorporeal membrane oxygenation to rescue sepsis-induced cardiogenic shock: a retrospective, multicentre, international cohort study

BACKGROUND

Patients with sepsis-induced cardiomyopathy with cardiogenic shock have a high mortality. This study assessed venoarterial extracorporeal membrane oxygenation (VA-ECMO) support for sepsis-induced cardiogenic shock refractory to conventional treatments.

METHODS

In this retrospective, multicentre, international cohort study, we compared outcomes of 82 patients (aged ≥18 years) with septic shock who received VA-ECMO at five academic ECMO centres, with 130 controls (not receiving ECMO) obtained from three large databases of septic shock. All patients had severe myocardial dysfunction (cardiac index 3 L/min per m2 or less or left ventricular ejection fraction [LVEF] 35% or less) and severe haemodynamic compromise (inotrope score at least 75 μg/kg per min or lactic acidaemia at least 4 mmol/L) at time of inclusion. The primary endpoint was survival at 90 days. A propensity score-weighted analysis was done to control for confounders.

FINDINGS

At baseline, patients treated with VA-ECMO had more severe myocardial dysfunction (mean cardiac index 1·5 L/min per m2vs 2·2 L/min per m2, LVEF 17% vs 27%), more severe haemodynamic impairment (inotrope score 279 μg/kg per min vs 145 μg/kg per min, lactataemia 8·9 mmol/L vs 6·5 mmol/L), and more severe organ failure (Sequential Organ Failure Assessment score 17 vs 13) than did controls, with p<0·0001 for each comparison. Survival at 90 days for patients treated with VA-ECMO was significantly higher than for controls (60% vs 25%, risk ratio [RR] for mortality 0·54, 95% CI [0·40-0·70]; p<0·0001). After propensity score weighting, ECMO remained associated with improved survival (51% vs 14%, adjusted RR for mortality 0·57, 95% CI [0·35-0·93]; p=0·0029). Lactate and catecholamine clearance were also significantly enhanced in patients treated with ECMO. Among the 49 survivors treated with ECMO, 32 who had been treated at the largest centre reported satisfactory Short Form-36 evaluated health-related quality of life at 1-year follow-up.

INTERPRETATION

Patients with severe sepsis-induced cardiogenic shock treated with VA-ECMO had a large and significant improvement in survival compared with controls not receiving ECMO. However, despite the careful propensity-weighted analysis, we cannot rule out unmeasured confounders.

FUNDING

None.