Effects of the endpoint adjudication process on the results of a randomised controlled trial: the ADVANCE trial

Clinical Adjudication of Hemodialysis Catheter-Related Bloodstream Infections: Findings from the REDUCCTION Trial

Key Points

The inter-rater reliability of reporting hemodialysis catheter-related infectious events between site investigators and trial adjudicators in Australia and New Zealand was substantial. The high concordance level in reporting catheter infections improves confidence in using site-level bacteremia rates as a clinical metric for quality benchmarking and future pragmatic clinical trials. A rigorous adjudication protocol may not be needed if clearly defined criteria to ascertain catheter-associated bacteremia are used.

Background

Hemodialysis catheter-related bloodstream infection (HD-CRBSI) are a significant source of morbidity and mortality among dialysis patients, but benchmarking remains difficult because of varying definitions of HD-CRBSI. This study explored the effect of clinical adjudication process on HD-CRBSI reporting.

Methods

The REDUcing the burden of Catheter ComplicaTIOns: a National approach trial implemented an evidence-based intervention bundle using a stepped-wedge design to reduce HD-CRBSI rates in 37 Australian kidney services. Six New Zealand services participated in an observational capacity. Adult patients with a new hemodialysis catheter between December 2016 and March 2020 were included. HD-CRBSI events reported were compared with the adjudicated outcomes using the end point definition and adjudication processes of the REDUcing the burden of Catheter ComplicaTIOns: a National approach trial. The concordance level was estimated using Gwet agreement coefficient (AC1) adjusted for service-level effects and implementation tranches (Australia only), with the primary outcome being the concordance of confirmed HD-CRBSI.

Results

A total of 744 hemodialysis catheter-related infectious events were reported among 7258 patients, 12,630 catheters, and 1.3 million catheter-exposure days. The majority were confirmed HD-CRBSI, with 77.9% agreement and substantial concordance (AC1=0.77; 95% confidence interval [CI], 0.73 to 0.81). Exit site infections have the highest concordance (AC1=0.85; 95% CI, 0.78 to 0.91); the greatest discordance was in events classified as other (AC1=0.33; 95% CI, 0.16 to 0.49). The concordance of all hemodialysis catheter infectious events remained substantial (AC1=0.80; 95% CI, 0.76 to 0.83) even after adjusting for the intervention tranches in Australia and overall service-level clustering.

Conclusions

There was a substantial level of concordance in overall and service-level reporting of confirmed HD-CRBSI. A standardized end point definition of HD-CRBSI resulted in comparable hemodialysis catheter infection rates in Australian and New Zealand kidney services. Consistent end point definition could enable reliable benchmarking outside clinical trials without the need for independent clinical adjudication.

A Common Data Element-Based Adjudication Process for mTBI Clinical Profiles: A Targeted Multidomain Clinical Trial Preliminary Study

INTRODUCTION

The primary purpose of this study was to examine the prevalence and percent agreement of clinician-identified mild traumatic brain injury (mTBI) clinical profiles and cutoff scores for selected Federal Interagency Traumatic Brain Injury Research common data elements (CDEs). A secondary purpose was to investigate the predictive value of established CDE assessments in determining clinical profiles in adults with mTBI.

MATERIALS AND METHODS

Seventy-one (23 males; 48 females) participants (M = 29.00, SD = 7.60, range 18-48 years) within 1-5 months (M = 24.20, SD = 25.30, range 8-154 days) of mTBI completed a clinical interview/exam and a multidomain assessment conducted by a licensed clinician with specialized training in concussion, and this information was used to identify mTBI clinical profile(s). A researcher administered CDE assessments to all participants, and scores exceeding CDE cutoffs were used to identify an mTBI clinical profile. The clinician- and CDE-identified clinical profiles were submitted to a multidisciplinary team for adjudication. The prevalence and percent agreement between clinician- and CDE-identified clinical profiles was documented, and a series of logistic regressions with adjusted odds ratios were performed to identify which CDE assessments best predicted clinician-identified mTBI clinical profiles.

RESULTS

Migraine/headache, vestibular, and anxiety/mood mTBI clinical profiles exhibited the highest prevalence and overall percent agreement among CDE and clinician approaches. Participants exceeding cutoff scores for the Global Severity Index and Headache Impact Test-6 assessments were 3.90 and 8.81 times more likely to have anxiety/mood and migraine/headache profiles, respectively. The Vestibular/Ocular Motor Screening vestibular items and the Pittsburgh Sleep Quality Index total score were predictive of clinician-identified vestibular and sleep profiles, respectively.

CONCLUSIONS

The CDEs from migraine/headache, vestibular, and anxiety/mood domains, and to a lesser extent the sleep modifier, may be clinically useful for identifying patients with these profiles following mTBI. However, CDEs for cognitive and ocular may have more limited clinical value for identifying mTBI profiles.

Cumulative Systolic Blood Pressure Load and Cardiovascular Risk in Patients With Diabetes

BACKGROUND

Standard measures of blood pressure (BP) do not account for both the magnitude and duration of exposure to elevated BP over time.

OBJECTIVES

The purpose of this study was to assess the association between cumulative systolic blood pressure (SBP) load and risk of cardiovascular events in patients with type 2 diabetes.

METHODS

A post hoc analysis of patients with type 2 diabetes followed by the ADVANCE-ON (Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified Release Controlled Evaluation - Observational Study). Cumulative SBP load was defined as the area under curve for SBP values ≥130 mm Hg divided by the area under curve for all measured SBP values over a 24-month exposure period. HRs for the association between cumulative SBP load with major cardiovascular events and death were estimated using Cox models.

RESULTS

Over a median 7.6 years of follow-up, 1,469 major cardiovascular events, 1,615 deaths, and 660 cardiovascular deaths were observed in 9,338 participants. Each 1-SD increase in cumulative SBP load was associated with a 14% increase in major cardiovascular events (HR: 1.14; 95% CI: 1.09-1.20), 13% increase in all-cause mortality (HR: 1.13; 95% CI: 1.13-1.18), and 21% increase in cardiovascular death (HR: 1.21; 95% CI: 1.13-1.29). For the prediction of cardiovascular events and death, cumulative SBP load outperformed mean SBP, time-below-target SBP, and visit-to-visit SBP variability in terms of Akaike information criterion and net reclassification indexes.

CONCLUSIONS

Cumulative SBP load may provide better prediction of major cardiovascular events compared with traditional BP measures among patients with type 2 diabetes. These findings reinforce the importance of both the magnitude and duration of exposure to elevated SBP in assessing cardiovascular risk. (Action in Diabetes and Vascular Disease Preterax and Diamicron MR Controlled Evaluation Post Trial Observational Study [ADVANCE-ON]; NCT00949286).

Clinical characteristics, time course, and outcomes of major bleeding according to bleeding site in patients with venous thromboembolism

BACKGROUND

Bleeding is the most dreaded complication of anticoagulant therapy for acute venous thromboembolism (VTE). Limited data exist about patient characteristics, time course and outcomes of major bleeding, according to the bleeding site.

METHODS

We used the data from the Registro Informatizado Enfermedad TromboEmbólica (RIETE) registry (03/2001-07/2018) and identified patients who suffered from major bleeding during anticoagulation. We assessed patient characteristics, time course, and 30-day outcomes including mortality, re-bleeding, and VTE recurrences, according to bleeding site.

RESULTS

Among 78,136 patients with VTE receiving anticoagulation, 2244 (2.9%) suffered from major bleeding (gastrointestinal in 800, intracranial in 417, hematoma in 410, genitourinary in 222, retroperitoneal in 145; other sites in 250). There were variations in baseline characteristics, including older age (P < 0.001) and predominance of women (70.2% [95% confidence interval [CI]]: 65.6-74.6% versus 50.5%, 95% CI: 48.2-52.9, P < 0.001) in patients with hematoma, compared with other patients. Overall, 82.7% of hematomas and 81.4% of retroperitoneal bleeds occurred in the first 90 days after the diagnosis of the VTE event, compared with only 50.6% of intracranial bleeds. Across the bleeding subgroups, 30-day all-cause mortality rates were highest in patients who suffered from intracranial bleeding (41.0%; 99% confidence interval [CI]: 34.8-47.4%), and lowest in patients who suffered from hematoma (17.8%; 99% CI: 13.2-23.2%). Patients who suffered from a major bleeding event in the first 30 days after VTE had significantly higher odds at 90-day follow-up to develop mortality (including from bleeding), recurrent VTE, and recurrent major bleeding (all Ps < 0.001). Variations were observed in the results according to the bleeding site.

CONCLUSIONS

Major bleeding is a serious complication in VTE patients. Patient characteristics, time course and outcomes varied substantially according to the bleeding site. Additional studies are needed to tease out the impact of patient risk factors, treatment regimens, and a potential distinct effect from the site of bleeding.

TRIAL REGISTRATION

https://clinicaltrials.gov/ct2/show/NCT02832245 (RIETE registry).

Severe undernutrition increases bleeding risk on vitamin-K antagonists

INTRODUCTION

Hemorrhage occurs in 7-10% of patients treated with vitamin K antagonist (VKA), with major bleeding in 1-3%. Impact of nutritional status on the bleeding risk of patients on anticoagulants is still poorly documented. Our study aimed to analyze the link between the nutritional status of patients on VKA and the occurrence of hemorrhagic events. We also analyzed micronutrients status.

METHODS

A case-control, monocentric, and prospective study was conducted from August 2012 to October 2015. The case patients were those presenting with major bleeding and control patients those without any bleeding under VKA treatment.

RESULTS

Overall, 294 patients under VKA treatment were paired according to age, gender, and index normalized ratio (INR). Out of these, 98 (33.3%) had major bleeding and 196 (66.7%) did not have any bleeding. Additionally, more than two-thirds of patients displayed undernutrition, which was more prevalent in bleeding than non-bleeding patients (OR = 1.85, CI95%: 1.07-3.21). There was a higher bleeding risk for those with severe undernutrition (OR = 2.66, CI95%: 1.58-4.46), with no difference found concerning moderate undernutrition. Bleeding patients had lower plasma-zinc concentrations than non-bleeding patients (9.4 ± 3.6 vs. 10.5 ± 3.7 μmol/L, p = 0.003); among them, there was a higher rate of patients with plasma zinc under 5 μmol/L (9% vs. 2%, p < 0.001).

CONCLUSION

Patients with undernutrition on VKA exhibit a significantly higher bleeding risk, which increases three-fold in case of severe undernutrition. The evaluation of nutritional status provides additional, valuable prognosis information prior to initiating VKA therapy. CLINICALTRIALS.

GOV NUMBER

NCT01742871.

Sex-specific associations between cardiovascular risk factors and myocardial infarction in patients with type 2 diabetes: The ADVANCE-ON study

AIM

To examine possible sex differences in the excess risk of myocardial infarction (MI) consequent to a range of conventional risk factors in a large-scale international cohort of patients with diabetes, and to quantify these potential differences both on the relative and absolute scales.

MATERIALS AND METHODS

Eleven thousand and sixty-five participants (42% women) with type 2 diabetes in the ADVANCE trial and its post-trial follow-up study, ADVANCE-ON, were included. Cox regression models were used to estimate hazard ratios (HRs) for associations between risk factors and MI (fatal and non-fatal) by sex, and the women-to-men ratio of HRs (RHR).

RESULTS

Over a median of 9.6 years of follow-up, 719 patients experienced MI. Smoking status, smoking intensity, higher systolic blood pressure (SBP), HbA1c, total and LDL cholesterol, duration of diabetes, triglycerides, body mass index (BMI) and lower HDL cholesterol were associated with an increased risk of MI in both sexes. Furthermore, some variables were associated with a greater relative risk of MI in women than men: RHRs were 1.75 (95% CI: 1.05-2.91) for current smoking, 1.53 (1.00-2.32) for former smoking, 1.18 (1.02-1.37) for SBP, and 1.13 (95% CI, 1.003-1.26) for duration of diabetes. Although incidence rates of MI were higher in men (9.3 per 1000 person-years) compared with women (5.8 per 1000 person-years), rate differences associated with risk factors were greater in women than men, except for HDL cholesterol and BMI.

CONCLUSIONS

In patients with type 2 diabetes, smoking, higher SBP and longer duration of diabetes had a greater relative and absolute effect in women than men, highlighting the importance of routine sex-specific approaches and early interventions in women with diabetes.

Stroke prevention in patients with type 2 diabetes or prediabetes. Recommendations from the Cerebrovascular Diseases Study Group, Spanish Society of Neurology

OBJECTIVE

To update the Spanish Society of Neurology's guidelines for stroke prevention in patients with type 2 diabetes or prediabetes, analysing the available evidence on the effect of metabolic control and the potential benefit of antidiabetic drugs with known vascular benefits in addition to conventional antidiabetic treatments in stroke prevention.

DEVELOPMENT

PICO-type questions (Patient, Intervention, Comparison, Outcome) were developed to identify practical issues in the management of stroke patients and to establish specific recommendations for each of them. Subsequently, we conducted systematic reviews of the PubMed database and selected those randomised clinical trials evaluating stroke as an independent variable (primary or secondary). Finally, for each of the PICO questions we developed a meta-analysis to support the final recommendations.

CONCLUSIONS

While there is no evidence that metabolic control reduces the risk of stroke, some families of antidiabetic drugs with vascular benefits have been shown to reduce these effects when added to conventional treatments, both in the field of primary prevention in patients presenting type 2 diabetes and high vascular risk or established atherosclerosis (GLP-1 agonists) and in secondary stroke prevention in patients with type 2 diabetes or prediabetes (pioglitazone).

Comparison of Outcome Adjudication by Investigators and by a Central End Point Committee in Heart Failure Trials

Background:

The usefulness of adjudication by central end point committees (CECs) is poorly assessed in heart failure (HF) trials. We aimed to assess its impact on the outcome of the SHIFT trial (Systolic HF Treatment With the If Inhibitor Ivabradine Trial).

Methods:

SHIFT was a randomized placebo-controlled trial investigating the effect of ivabradine in 6505 HF patients with reduced ejection fraction. Prespecified end points, reported by investigators (all cardiologists) using specific case report form pages, included all-cause and specific causes of deaths and hospitalizations. The primary end point was a composite of cardiovascular deaths or hospitalizations for worsening HF. We compared the adjudication of prespecified end points made by investigators and by the CEC.

Results:

Investigators identified 7529 prespecified end points, 6793 of which were confirmed by the CEC: 98.1% of cardiovascular deaths, 88.6% of all hospitalizations, and 84.4% of hospitalizations for worsening HF. These differences had no meaningful impact on the study results; hazard ratio for the primary composite end point: investigators, 0.83 (95% CI, 0.76–0.91) versus CEC, 0.82 (95% CI, 0.75–0.90), with similar results for each component of the primary end point (hazard ratio of 0.92 versus 0.91 for cardiovascular death and 0.78 versus 0.74 for hospitalization for worsening HF).

Conclusions:

Central adjudication by a CEC in the SHIFT study confirmed most of cardiovascular deaths and worsening HF hospitalizations assessed by cardiologists and did not result in a significant change of the final result as compared to investigator judgment. In this context, the benefits of CEC in blinded HF trials should be reconsidered.

Registration:

URL: https://www.clinicaltrials.gov ; Unique identifier: NCT02441218. URL: http://www.isrctn.com/ISRCTN70429960 ; Unique identifier: ISRCTN70429960.

Scientific independence and objectivity: many questions linger about treatment of type 2 diabetes, such as scientific study design, optimal glucose control and the safety of injecting exogenous insulin

Whilst clinical guidelines exist for the treatment of people with type 2 diabetes, many underlying assumptions are still not qualified by convincing evidence. In this commentary, it is argued that fundamental issues still cloud clinical practice, such as biases in the design of clinical studies, the association between glucose control & clinical outcomes, and the safety of exposure to exogenous insulin and other glucose-lowering drugs. Relevant scientific evidence and alternative opinions about important issues continue to be largely ignored, and no effort has been made to resolve these questions. This may have had serious consequences, such as stifling innovation because there are no further benefits to be achieved in relation to glucose control.

Assessment of the End Point Adjudication Process on the Results of the Platelet-Oriented Inhibition in New TIA and Minor Ischemic Stroke (POINT) Trial: A Secondary Analysis

IMPORTANCE

Debate continues about the value of event adjudication in clinical trials and whether independent centralized assessments improve reliability and validity of study results in masked randomized trials compared with local, investigator-assessed end points.

OBJECTIVE

To assess the results of the adjudicated end point process in the Platelet-Oriented Inhibition in New TIA and Minor Ischemic Stroke (POINT) trial by comparing end points assessed by local site investigators with centrally adjudicated end points.

DESIGN, SETTING, AND PARTICIPANTS

This is an ad hoc secondary analysis of a randomized, double-blind clinical trial comparing safety and effectiveness of clopidogrel bisulphate plus aspirin vs placebo plus aspirin. Patients received either 600 mg of clopidogrel bisulphate on day 1, then 75 mg per day through day 90 plus 50 to 325 mg of aspirin per day, or the same range of dosages of placebo plus aspirin. Investigators reported all potential end points; independent masked adjudicators were randomly assigned to review using definitions specified in the study protocol. This was a multicenter study; 269 international sites in 10 countries enrolled from May 28, 2010, to December 19, 2017. The study enrolled 4881 patients 18 years or older with transient ischemic attack or minor acute ischemic stroke within 12 hours of symptom onset and followed for 90 days from randomization; last follow-up was completed in March 2018.

MAIN OUTCOMES AND MEASURES

Independent adjudicators external to the study and masked to study treatment assignment adjudicated 467 primary and secondary effectiveness outcomes and major and minor bleeding events, including the primary composite end point, which was the risk of a composite of major ischemic events at 90 days, defined as ischemic stroke, myocardial infarction, or death from an ischemic vascular event. The primary safety end point was major hemorrhage. All components of the primary and safety outcomes were adjudicated.

RESULTS

In this secondary analysis of an international randomized clinical trial, a total of 269 sites worldwide randomized 4881 patients (median age, 65.0 years; interquartile range, 55-74 years); 55.0% were male. The primary results have been published previously. The hazard ratios for clopidogrel plus aspirin vs placebo plus aspirin for the primary composite end point were 0.75 (95% CI, 0.59-0.95) for adjudicator-assessed events and 0.76 (95% CI, 0.60-0.95) for investigator-assessed events. Agreement between adjudicator and investigator assessments was 90.7%. The hazard ratios for clopidogrel plus aspirin vs placebo plus aspirin for the primary safety end point were 2.32 (95% CI, 1.10-4.87) for adjudicator-assessed events and 2.58 (95% CI, 1.19-5.58) for investigator-assessed events, with an agreement rate of 77.5%.

CONCLUSIONS AND RELEVANCE

Independent end point adjudication did not substantially alter estimates of the primary treatment effectiveness in the POINT trial.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00991029.

Outcome Assessment by Central Adjudicators Versus Site Investigators in Stroke Trials: A Systematic Review and Meta-Analysis

Background and Purpose- In randomized stroke trials, central adjudication of a trial's primary outcome is regularly implemented. However, recent evidence questions the importance of central adjudication in randomized trials. The aim of this review was to compare outcomes assessed by central adjudicators with outcomes assessed by site investigators. Methods- We included randomized stroke trials where the primary outcome had undergone an assessment by site investigators and central adjudicators. We searched MEDLINE, EMBASE, CENTRAL (Cochrane Central Register of Controlled Trials), Web of Science, PsycINFO, and Google Scholar for eligible studies. We extracted information about the adjudication process as well as the treatment effect for the primary outcome, assessed both by central adjudicators and by site investigators. We calculated the ratio of these treatment effects so that a ratio of these treatment effects >1 indicated that central adjudication resulted in a more beneficial treatment effect than assessment by the site investigator. A random-effects meta-analysis model was fitted to estimate a pooled effect. Results- Fifteen trials, comprising 69 560 participants, were included. The primary outcomes included were stroke (8/15, 53%), a composite event including stroke (6/15, 40%) and functional outcome after stroke measured on the modified Rankin Scale (1/15, 7%). The majority of site investigators were blind to treatment allocation (9/15, 60%). On average, there was no difference in treatment effect estimates based on data from central adjudicators and site investigators (pooled ratio of these treatment effects=1.02; 95% CI, [0.95-1.09]). Conclusions- We found no evidence that central adjudication of the primary outcome in stroke trials had any impact on trial conclusions. This suggests that potential advantages of central adjudication may not outweigh cost and time disadvantages in stroke studies if the primary purpose of adjudication is to ensure validity of trial findings.

Tight systolic blood pressure control with combination therapy decreases type 2 endoleaks in patients undergoing endovascular aneurysm repair

BACKGROUND

Endovascular aneurysm repair (EVAR) has revolutionized the treatment of abdominal aortic aneurysm (AAA) disease. However, the survival advantage is lost in the long term due the occurrence of endoleaks affecting the late rupture of aneurism sac. Few data are available on the role of blood pressure control in affecting the incidence of type 2 endoleaks in patients undergoing EVAR.

OBJECTIVE

Aim of this study was to evaluated whether systolic blood pressure (SBP) control to target 130 mmHg reached after preoperative cardiology consultant might decrease the incidence of type II endoleak(T2E), sac expansion and related aortic reintervention after elective endovascular aneurysm repair(EVAR).

METHODS

We analyzed 386 patients undergoing EVAR between 2008 and 2016. The primary endpoints were T2E, sac expansion and related aortic re-intervention or sac shrinkage during a median follow-up of 24 months [12-48]. The secondary endpoint was every cause of vascular or cardiac morbidity and mortality.

RESULTS

The SBP value of 130 mmHg at the time of EVAR resulted, at ROC curve analysis, the most sensitive and specific for all the analyzed endpoints (T2E, n = 74; sac expansion n = 19; re-intervention, n = 10, sac shrinkage, n = 72). The combination antihypertensive therapy showed a significant inverse relationship with T2E occurrence. The incidence of primary endpoints was significantly higher (p < 0.001) in patients with SBP ≥ 130 mmHg. Cardiovascular death was significantly more prevalent (p < 0,001) in patients with SBP ≥130 mmHg. These findings were confirmed at the multivariable Cox regression analysis [primary endpoint HR = 0.09(0.06-0.15), p < 0.001; cardiovascular death HR = 0.33(0.12-0.85), p = 0.023].

CONCLUSIONS

Tight SBP control at the target of 130 mmHg at the time of elective EVAR significantly decreases TE2 occurrence, need of re-intervention and cardiovascular death in a prolonged follow-up of a large sample of patients.

FDA guidance on antihyperglyacemic therapies for type 2 diabetes: One decade later

In 2008, the US Food and Drug Administration (FDA) issued a guidance to industry statement concerning evaluation of the cardiovascular (CV) safety of new antihyperglycaemic therapies for type 2 diabetes. Fifteen CV outcome trials assessing three novel classes of antihyperglycaemic therapies, DPP-4 inhibitors, GLP-1 receptor agonists and SGLT-2 inhibitors, were completed by the end of 2018 and several others are ongoing. In addition, one comparative insulin trial also has been completed. None of these trials reported an increase in risk for major adverse CV events (MACE), and six agents have demonstrated CV benefits. This experience has led to the first FDA-approved indications for antihyperglycaemic medications to reduce the risk of CV death (empagliflozin) and to reduce the risk of MACE (liraglutide, canagliflozin), both indications specific to patients with established atherosclerotic cardiovascular disease (ASCVD). Because of the aggregate results from dedicated CV outcomes trials conducted in response to the FDA guidance statement, the contemporary paradigm for treatment of patients with type 2 diabetes has evolved substantially. However, the guidance has substantially increased the cost of developing new medications to address this important disease that afflicts hundreds of millions of adults worldwide, with reduction in quality of life as well as in life expectancy. The cost burden of drug development of medications proven effective that may directly impact cost to patients and to their insurers might be alleviated by modifications to the present guidance statement. These include areas of trial design, aspects of trial operation, expansion of composite outcomes to include broader component CV outcomes and continued evolution of analytic methodology. The guidance statement will benefit from consideration of a number of modifications to support continued innovation and, of course, the safety of marketed medications for type 2 diabetes. However, the requirement to assess each new antihyperglycaemic medication in at least one large-scale standard randomized clinical outcomes trial should remain, so that clinicians can be reassured about the favourable efficacy/safety profiles of the medications they prescribe.

Central masked adjudication of stroke diagnosis at trial entry offered no advantage over diagnosis by local clinicians: Secondary analysis and simulation

BACKGROUND

Central adjudication of stroke type is commonly implemented in large multicentre clinical trials. We investigated the effect of central adjudication of diagnosis of stroke type at trial entry in the Efficacy of Nitric Oxide in Stroke (ENOS) trial.

METHODS

ENOS recruited patients with acute ischaemic or haemorrhagic stroke, and diagnostic adjudication was carried out using cranial scans. For this study, diagnoses made by local site clinicians were compared with those by central, masked adjudicators using kappa statistics. The trial primary analysis and subgroup analysis by stroke type were re-analysed using stroke diagnosis made by local clinicians, and simulations were used to assess the impact of increased non-differential misclassification and subgroup effects.

RESULTS

Agreement on stroke type (Ischaemic, Intracerebral Haemorrhage, Unknown stroke type, No-stroke) was high (κ = 0.92). Adjudication of stroke type had no impact on the primary outcome or subgroup analysis by stroke type. With misclassification increased to 10 times the level observed in ENOS and a simulated subgroup effect present, adjudication would have affected trial conclusions.

CONCLUSIONS

Stroke type at trial entry was diagnosed accurately by local clinicians in ENOS. Adjudication of stroke type by central adjudicators had no measurable effect on trial conclusions. Diagnostic adjudication may be important if diagnosis is complex and a treatment-diagnosis interaction is expected.

Management and outcome of major bleeding in patients receiving vitamin K antagonists for venous thromboembolism

BACKGROUND

The optimal management of major bleeding in patients receiving vitamin K antagonists (VKA) for venous thromboembolism (VTE) is unclear.

METHODS

We used the RIETE (Registro Informatizado Enfermedad TromboEmbólica) registry to assess the management and 30-day outcomes after major bleeding in patients receiving VKA for VTE.

RESULTS

From January 2013 to December 2017, 267 of 18,416 patients (1.4%) receiving long-term VKA for VTE had a major bleeding (in the gastrointestinal tract 78, intracranial 72, hematoma 50, genitourinary 20, other 47). Overall, 151 patients (57%) received blood transfusion; 110 (41%) vitamin K; 37 (14%) fresh frozen plasma; 29 (11%) pro-haemostatic agents and 20 (7.5%) a vena cava filter. During the first 30 days, 59 patients (22%) died (41 died of bleeding) and 13 (4.9%) had a thrombosis. On multivariable analysis, patients with intracranial bleeding (hazard ratio [HR]: 4.58; 95%CI: 2.40-8.72) and those with renal insufficiency at baseline (HR: 2.73; 95%CI: 1.45-5.15) had an increased mortality risk, whereas those receiving vitamin K had a lower risk (HR: 0.47; 0.24-0.92). On the other hand, patients receiving fresh frozen plasma were at increased risk for thrombotic events (HR: 4.22; 95%CI: 1.25-14.3).

CONCLUSIONS

Major bleeding in VTE patients receiving VKA carries a high mortality rate. Intracranial bleeding and renal insufficiency increased the risk. Fresh frozen plasma seems to increase this risk for recurrent VTE.

A comparison of approaches for adjudicating outcomes in clinical trials

Background

Incorrect classification of outcomes in clinical trials can lead to biased estimates of treatment effect and reduced power. Ensuring appropriate adjudication methods to minimize outcome misclassification is therefore essential. While there are many reported adjudication approaches, there is little consensus over which approach is best.

Methods

Under the assumption of non-differential assessment (i.e. that misclassification rates are the same in each treatment arm, as would typically be the case when outcome assessors are blinded), we use simulation and theoretical results to address four different questions about outcome adjudication: (a) How many assessors should be used? (b) When is it better to use onsite or central assessment? (c) Should central assessors adjudicate all outcomes, or only suspected events? (d) Should central assessment with multiple assessors be done independently or through group consensus?

Results

No one adjudication approach performs optimally in all settings. The optimal approach depends on the misclassification rates of site and central assessors, and the correlation between assessors. We found: (a) there will generally be little incremental benefit to using more than three assessors and, for outcomes with very high correlation between assessors, using one assessor is sufficient; (b) when choosing between site and central assessors, the assessor with the smallest misclassification rate should be chosen; when these rates are unknown, a combination of one site assessor and two central assessors will provide good results across a range of scenarios; (c) having central assessors adjudicate only suspected events will typically increase bias, and should be avoided, unless the threshold for sending outcomes for central assessment is extremely low; (d) central assessors can adjudicate either independently or in a group, and the preferred option should be dictated by whichever is expected to have the lowest misclassification rate.

Conclusions

Outcome adjudication is of critical importance to ensure validity of trial results, although no one approach is optimal across all settings. Investigators should choose the best strategy based on the specific characteristics of their trial. Regardless of the adjudication strategy chosen, assessors should be qualified and receive appropriate training.

Prognostic Value of Variability in Systolic Blood Pressure Related to Vascular Events and Premature Death in Type 2 Diabetes Mellitus: The ADVANCE-ON Study

Visit-to-visit variability in systolic blood pressure (SBP) is a risk factor for cardiovascular events. However, whether it provides additional predictive information beyond traditional risk factors, including mean SBP, in the long term is unclear. The ADVANCE trial (Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified Release Controlled Evaluation) was a randomized controlled trial in patients with type 2 diabetes mellitus; ADVANCE-ON (ADVANCE-Observational) followed-up patients subsequently. In these analyses, 9114 patients without major macrovascular or renal events or death during the first 24 months were included. Data on SBP from 6 visits during the first 24 months after randomization were used to estimate visit-to-visit variability in several ways: the primary measure was the standard deviation. Events accrued during the following 7.6 years. The primary outcome was a composite of major macrovascular and renal events and all-cause mortality. Standard deviation of SBP was log-linearly associated with an increased risk of the primary outcome (P<0.001) after adjustment for mean SBP and other cardiovascular risk factors. The hazard ratio (HR; 95% confidence interval [CI]) in the highest, compared with the lowest, tenth of the standard deviation was 1.39 (1.15-1.69). Results were similar for major macrovascular events alone and all-cause mortality alone (both P<0.01). Addition of standard deviation of SBP significantly improved 8-year risk classification (continuous net reclassification improvement, 5.3%). Results were similar for other measures of visit-to-visit variability, except maximum SBP. Visit-to-visit variability in SBP is an independent predictor of vascular complications and death, which improves risk prediction beyond that provided by traditional risk factors, including mean SBP.

Microvascular and Macrovascular Disease and Risk for Major Peripheral Arterial Disease in Patients With Type 2 Diabetes

OBJECTIVE

Peripheral arterial disease (PAD) is a common manifestation of atherosclerosis in type 2 diabetes, but the relationship between other vascular diseases and PAD has been poorly investigated. We examined the impact of previous microvascular and macrovascular disease on the risk of major PAD in patients with type 2 diabetes.

RESEARCH DESIGN AND METHODS

We analyzed 10,624 patients with type 2 diabetes free from baseline major PAD in the Action in Diabetes and Vascular Disease: Preterax and Diamicron MR Controlled Evaluation (ADVANCE) clinical trial. The primary composite outcome was major PAD defined as PAD-induced death, peripheral revascularization, lower-limb amputation, or chronic ulceration. The secondary end points were the PAD components considered separately.

RESULTS

Major PAD occurred in 620 (5.8%) participants during 5 years of follow-up. Baseline microvascular and macrovascular disease were both associated with subsequent risk of major PAD after adjustment for age, sex, region of origin, and randomized treatments. However, only microvascular disease remained significantly associated with PAD after further adjustment for established risk factors. The highest risk was observed in participants with a history of macroalbuminuria (hazard ratio 1.91 [95% CI 1.38-2.64], P < 0.0001) and retinal photocoagulation therapy (1.60 [1.11-2.32], P = 0.01). Baseline microvascular disease was also associated with a higher risk of chronic lower-limb ulceration (2.07 [1.56-2.75], P < 0.0001) and amputation (1.59 [1.15-2.22], P = 0.006), whereas baseline macrovascular disease was associated with a higher rate of angioplasty procedures (1.75 [1.13-2.73], P = 0.01).

CONCLUSIONS

Microvascular disease, particularly macroalbuminuria and retinal photocoagulation therapy, strongly predicts major PAD in patients with type 2 diabetes, but macrovascular disease does not.

The Inaccuracy of Patient Recall for COPD Exacerbation Rate Estimation and Its Implications: Results from Central Adjudication

BACKGROUND

COPD exacerbation incidence rates are often ascertained retrospectively through patient recall and self-reports. We compared exacerbation ascertainment through patient self-reports and single-physician chart review to central adjudication by a committee and explored determinants and consequences of misclassification.

METHODS

Self-reported exacerbations (event-based definition) in 409 primary care patients with COPD participating in the International Collaborative Effort on Chronic Obstructive Lung Disease: Exacerbation Risk Index Cohorts (ICE COLD ERIC) cohort were ascertained every 6 months over 3 years. Exacerbations were adjudicated by single experienced physicians and an adjudication committee who had information from patient charts. We assessed the accuracy (sensitivities and specificities) of self-reports and single-physician chart review against a central adjudication committee (AC) (reference standard). We used multinomial logistic regression and bootstrap stability analyses to explore determinants of misclassifications.

RESULTS

The AC identified 648 exacerbations, corresponding to an incidence rate of 0.60 ± 0.83 exacerbations/patient-year and a cumulative incidence proportion of 58.9%. Patients self-reported 841 exacerbations (incidence rate, 0.75 ± 1.01; incidence proportion, 59.7%). The sensitivity and specificity of self-reports were 84% and 76%, respectively, those of single-physician chart review were between 89% and 96% and 87% and 99%, respectively. The multinomial regression model and bootstrap selection showed that having experienced more exacerbations was the only factor consistently associated with underreporting and overreporting of exacerbations (underreporters: relative risk ratio [RRR], 2.16; 95% CI, 1.76-2.65 and overreporters: RRR, 1.67; 95% CI, 1.39-2.00).

CONCLUSIONS

Patient 6-month recall of exacerbation events are inaccurate. This may lead to inaccurate estimates of incidence measures and underestimation of treatment effects. The use of multiple data sources combined with event adjudication could substantially reduce sample size requirements and possibly cost of studies.

CLINICAL TRIAL REGISTRATION

www.ClinicalTrials.gov, NCT00706602.

Use of administrative data to increase the practicality of clinical trials: Insights from the Women's Health Initiative

BACKGROUND

To reduce research costs in the context of pragmatic trials, consideration is given to using administrative data (Medicare claims) to ascertain clinical outcomes.

METHODS

In the historical context of the Women's Health Initiative, the correspondence between selected cardiovascular events derived from Medicare claims was compared to those documented and adjudicated in this large-scale prevention trial.

RESULTS

Classification performance varies somewhat by type of outcome, but hazard ratios and confidence intervals derived from the two data sources were quite comparable.

CONCLUSION

These encouraging results provided the needed support to launch a new embedded pragmatic trial of physical activity that will rely heavily on Medicare claims to ascertain cardiovascular disease incidence in the majority of those randomized.

Comparison of central adjudication of outcomes and onsite outcome assessment on treatment effect estimates

BACKGROUND

Assessment of events by adjudication committees (ACs) is recommended in multicentre randomised controlled trials (RCTs). However, its usefulness has been questioned.

OBJECTIVES

The aim of this systematic review was to compare 1) treatment effect estimates of subjective clinical events assessed by onsite assessors versus by AC, and 2) treatment effect estimates according to the blinding status of the onsite assessor as well as the process used to select events to adjudicate.

SEARCH METHODS

We searched Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, EMBASE, PsycINFO, CINAHL and Google Scholar (25 August 2015 as the last updated search date), using a combination of terms to retrieve RCTs with commonly used terms to describe ACs.

SELECTION CRITERIA

We included all reports of RCTs and the published RCTs included in reviews and meta-analyses that reported the same subjective outcome event assessed by both an onsite assessor and an AC.

DATA COLLECTION AND ANALYSIS

We extracted the odds ratio (OR) from onsite assessment and the corresponding OR from AC assessment and calculated the ratio of the odds ratios (ROR). A ratio of odds ratios < 1 indicated that onsite assessors generated larger effect estimates in favour of the experimental treatment than ACs.

MAIN RESULTS

Data from 47 RCTs (275,078 patients) were used in the meta-analysis. We excluded 11 RCTs because of incomplete outcome data to calculate the OR for onsite and AC assessments. On average, there was no difference in treatment effect estimates from onsite assessors and AC (combined ROR: 1.00, 95% confidence interval (CI) 0.97 to 1.04; I(2) = 0%, 47 RCTs). The combined ROR was 1.00 (95% CI 0.96 to 1.04; I(2) = 0%, 35 RCTs) when onsite assessors were blinded; 0.76 (95% CI 0.48 to 1.12, I(2) = 0%, two RCTs) when AC assessed events identified independently from unblinded onsite assessors; and 1.11 (95% CI 0.96 to 1.27, I(2) = 0%, 10 RCTs) when AC assessed events identified by unblinded onsite assessors. However, there was a statistically significant interaction between these subgroups (P = 0.03) AUTHORS' CONCLUSIONS: On average, treatment effect estimates for subjective outcome events assessed by onsite assessors did not differ from those assessed by ACs. Results of subgroup analysis showed an interaction according to the blinded status of onsite assessors and the process used to submit data to AC. These results suggest that the use of ACs might be most important when onsite assessors are not blinded and the risk of misclassification is high. Furthermore, research is needed to explore the impact of the different procedures used to select events to adjudicate.

Architecture design of a generic centralized adjudication module integrated in a web-based clinical trial management system

BACKGROUND

Centralized outcome adjudication has been used widely in multicenter clinical trials in order to prevent potential biases and to reduce variations in important safety and efficacy outcome assessments. Adjudication procedures could vary significantly among different studies. In practice, the coordination of outcome adjudication procedures in many multicenter clinical trials remains as a manual process with low efficiency and high risk of delay. Motivated by the demands from two large clinical trial networks, a generic outcome adjudication module has been developed by the network's data management center within a homegrown clinical trial management system. In this article, the system design strategy and database structure are presented.

METHODS

A generic database model was created to transfer different adjudication procedures into a unified set of sequential adjudication steps. Each adjudication step was defined by one activate condition, one lock condition, one to five categorical data items to capture adjudication results, and one free text field for general comments. Based on this model, a generic outcome adjudication user interface and a generic data processing program were developed within a homegrown clinical trial management system to provide automated coordination of outcome adjudication.

RESULTS

By the end of 2014, this generic outcome adjudication module had been implemented in 10 multicenter trials. A total of 29 adjudication procedures were defined with the number of adjudication steps varying from 1 to 7. The implementation of a new adjudication procedure in this generic module took an experienced programmer 1 or 2 days. A total of 7336 outcome events had been adjudicated and 16,235 adjudication step activities had been recorded. In a multicenter trial, 1144 safety outcome event submissions went through a three-step adjudication procedure and reported a median of 3.95 days from safety event case report form submission to adjudication completion. In another trial, 277 clinical outcome events were adjudicated by a six-step procedure and took a median of 23.84 days from outcome event case report form submission to adjudication procedure completion.

CONCLUSION

A generic outcome adjudication module integrated in the clinical trial management system made the automated coordination of efficacy and safety outcome adjudication a reality.

Central Reading of Endoscopy Endpoints in Inflammatory Bowel Disease Trials

BACKGROUND

Central reading of endoscopy (CROE) is crucial in determining who qualifies for a trial but also has a role, independent of the selected scoring system, in decreasing measurement noise that can obscure separation between placebo and active drug. Benefits of CROE may not be independent of the method chosen, and controversy exists about the ideal approach.

METHODS

Literature review and concept development.

RESULTS

Components to be considered in the reading algorithm are blinding, number of central readers, independent voting versus consensus panel, video recordings versus still images, and involvement of the site reader. Key concepts considered are endpoints, bias, power, and sample size derived from the Food and Drug Administration and European Medicines Agency guidelines, as well as the technological requirements and recruitment, qualification, and revalidation of central readers as applied to CROE.

CONCLUSIONS

Recording and CROE should be standardized, and an imaging charter developed with research on the different components and its overall impact.

Follow-up of blood-pressure lowering and glucose control in type 2 diabetes

BACKGROUND

In the Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified Release Controlled Evaluation (ADVANCE) factorial trial, the combination of perindopril and indapamide reduced mortality among patients with type 2 diabetes, but intensive glucose control, targeting a glycated hemoglobin level of less than 6.5%, did not. We now report results of the 6-year post-trial follow-up.

METHODS

We invited surviving participants, who had previously been assigned to perindopril-indapamide or placebo and to intensive or standard glucose control (with the glucose-control comparison extending for an additional 6 months), to participate in a post-trial follow-up evaluation. The primary end points were death from any cause and major macrovascular events.

RESULTS

The baseline characteristics were similar among the 11,140 patients who originally underwent randomization and the 8494 patients who participated in the post-trial follow-up for a median of 5.9 years (blood-pressure-lowering comparison) or 5.4 years (glucose-control comparison). Between-group differences in blood pressure and glycated hemoglobin levels during the trial were no longer evident by the first post-trial visit. The reductions in the risk of death from any cause and of death from cardiovascular causes that had been observed in the group receiving active blood-pressure-lowering treatment during the trial were attenuated but significant at the end of the post-trial follow-up; the hazard ratios were 0.91 (95% confidence interval [CI], 0.84 to 0.99; P=0.03) and 0.88 (95% CI, 0.77 to 0.99; P=0.04), respectively. No differences were observed during follow-up in the risk of death from any cause or major macrovascular events between the intensive-glucose-control group and the standard-glucose-control group; the hazard ratios were 1.00 (95% CI, 0.92 to 1.08) and 1.00 (95% CI, 0.92 to 1.08), respectively.

CONCLUSIONS

The benefits with respect to mortality that had been observed among patients originally assigned to blood-pressure-lowering therapy were attenuated but still evident at the end of follow-up. There was no evidence that intensive glucose control during the trial led to long-term benefits with respect to mortality or macrovascular events. (Funded by the National Health and Medical Research Council of Australia and others; ADVANCE-ON ClinicalTrials.gov number, NCT00949286.).

The Role of MicroRNAs in Diabetic Complications-Special Emphasis on Wound Healing

Overweight and obesity are major problems in today’s society, driving the prevalence of diabetes and its related complications. It is important to understand the molecular mechanisms underlying the chronic complications in diabetes in order to develop better therapeutic approaches for these conditions. Some of the most important complications include macrovascular abnormalities, e.g., heart disease and atherosclerosis, and microvascular abnormalities, e.g., retinopathy, nephropathy and neuropathy, in particular diabetic foot ulceration. The highly conserved endogenous small non-coding RNA molecules, the micro RNAs (miRNAs) have in recent years been found to be involved in a number of biological processes, including the pathogenesis of disease. Their main function is to regulate post-transcriptional gene expression by binding to their target messenger RNAs (mRNAs), leading to mRNA degradation, suppression of translation or even gene activation. These molecules are promising therapeutic targets and demonstrate great potential as diagnostic biomarkers for disease. This review aims to describe the most recent findings regarding the important roles of miRNAs in diabetes and its complications, with special attention given to the different phases of diabetic wound healing.

Agreement between public register and adjudication committee outcome in a cardiovascular randomized clinical trial

The objective of this study is to describe the agreement between randomized trial outcome assessment by committee and outcomes entirely identified through public registers.

METHODS

In the CLARICOR trial, 4,372 patients with stable coronary heart disease received a short course of clarithromycin versus placebo and were followed up for 2.6 years. The pertinent hospital records and death certificates had originally been evaluated by the adjudication committee using common definitions of outcomes mapped into a 6-category list. We now mechanically converted the International Classification of Diseases-coded diagnoses of the public registries into the same categories. After cross-tabulation of the committee diagnoses with National Patient Register diagnoses and Register of Causes of Death, we calculate agreement and compare the estimated intervention effects of the 2 data sets.

RESULTS

With public register data, the protocol-specified categories were slightly more frequent. Overall agreement was 74% for hospital discharges and 60% for cause of death, but the intervention effect, expressed as a hazard ratio, stayed within 4% of the value originally obtained with the adjudication committee (P ≥ .35).

CONCLUSIONS

Our results show a modest agreement between formal adjudication and outcomes deducible from public registers. However, the estimated intervention effect did not differ noticeably between the 2 data sources. If studies on a wide range of public registers confirm these findings, register outcomes may be considered as a replacement for adjudication committees.