Real-world management and outcomes of 7 million patients with acute coronary syndrome according to clinical research trial enrolment status: a propensity matched analysis

Measuring Representativeness in Clinical Trials

Representativeness in randomized clinical trials remains a critical concern, affecting the external validity of trial results, equitable access to the risks and benefits of research participation, and public trust in clinical research. Although representative participation by members of groups traditionally underrepresented in clinical trials is just a surrogate for true diversity, equity, inclusion, and belonging in clinical trials, it can be quantified, allowing stakeholders to add empirical rigor to diversity, equity, inclusion, and belonging efforts. Multiple ways to measure representativeness have been proposed, including the participation-to-prevalence ratio, raw participation proportions or numbers for relevant subgroups, and enrollment fraction for relevant subgroups. These methods have strengths and weaknesses and may be appropriate to report in certain circumstances, depending on why stakeholders seek to assess representativeness. Stakeholders-including regulatory agencies, journal editors, clinical trial investigators, and trial sponsors-may use quantitative measures of representativeness to establish trial enrollment standards, monitor equitable participation in ongoing trials, and condition funding or drug or device approval on achieving specific representativeness targets. However, using quantitative measures of representativeness in this way could have unintended consequences, including researchers "gaming" recruitment strategies to meet target numbers, overlooking nuanced variations within communities, and potentially incentivizing problematic and exploitative recruitment strategies. Although no single method of measuring representativeness offers a comprehensive solution for increasing diversity, equity, inclusion, and belonging in all randomized clinical trials, a carefully designed, multifaceted approach to measuring representativeness may provide stakeholders with useful perspectives for measuring progress in increasing the diversity of clinical trial participation. For stakeholders seeking a single number to assess the representativeness of a trial enrolling patients with a disease state with well-delineated demographics, the participation-to-prevalence ratio is ideal; however, for a more nuanced view of representativeness, the combination of enrollment fraction in subgroups of relevance plus a full report of the demographics of patients approached for enrollment may be more appropriate.

30-Day unplanned readmission rates, causes and outcomes of patients hospitalized for acute coronary syndrome based on the trial participation status

BACKGROUND

This study aimed to investigate the association between index trial participation status and 30-day unplanned readmission rates, causes, and outcomes in acute coronary syndrome (ACS) patients.

METHODS

The National Readmission Database was analysed for all index hospitalizations with a principal diagnosis of ACS between October 2015 to November 2019, stratified by index trial participation status (International Classification of Diseases - 10th edition code: Z00.6). The 30-day unplanned readmission rates, causes and outcomes were analysed, including the assessment of factors associated with readmission. Multivariable regression analyses were reported as adjusted odds ratios (aOR) with 95 % confidence intervals (95 % CI). All analyses were weighted and utilized hierarchical multi-level organization.

RESULTS

A total of 2,066,328 cases with a principal diagnosis of ACS were included in the study, of which there were 4061 trial participants (0.2 %) and 189,240 (9.2 %) cases experienced unplanned 30-day readmission. Rates of unplanned 30-day readmission were similar between trial participants and non-participants (9.8 % vs. 9.2 %, p = 0.16). Consistently, after multivariable adjustment, there was no significant association between trial participation and unplanned 30-day readmissions (aOR 0.96, 95 % CI 0.86-1.07, p = 0.45). Compared with trial participants, the majority of readmissions in non-participants were related to cardiovascular conditions (55.2 % vs. 46.7 %, p = 0.005, respectively). There was no significant difference in all-cause mortality (5.5 % vs. 4.6 %, p = 0.368, respectively), but trial participants were more likely to develop major bleeding (3.5 % vs. 2.1 %, p = 0.044), ischemic stroke (4.0 % vs. 2.1 %, p = 0.008) and haemorrhagic stroke (2.0 % vs. 0.6 %, p < 0.001) at readmissions.

CONCLUSION

Overall rates of unplanned 30-day readmissions after ACS are similar between trial participants and non-participants, but non-participation in trials was associated with a higher likelihood of cardiovascular readmission.

Major bleeding in patients with atrial fibrillation treated with apixaban versus warfarin in combination with amiodarone: nationwide cohort study

BACKGROUND

Amiodarone is an established treatment for atrial fibrillation (AF) but might interfere with the metabolism of apixaban or warfarin. Therefore, the aim was to investigate the occurrence of major bleeding among patients with AF treated with amiodarone in combination with apixaban or warfarin.

METHODS

Retrospective observational study using Swedish health registers. All patients with AF in the National Patient Register and the National Dispensed Drug Register with concomitant use of amiodarone and warfarin or apixaban between 1 June 2013 and 31 December 2018 were included. Propensity score matching was performed, and matched cohorts were compared using Cox proportional HRs. The primary outcome was major bleeding resulting in hospitalisation based on International Classification of Diseases (ICD)-10 codes. Secondary outcomes included intracranial bleeding, gastrointestinal bleeding and other bleeding. Exploratory outcomes included ischaemic stroke/systemic embolism and all-cause/cardiovascular (CV) mortality.

RESULTS

A total of 12 103 patients met the inclusion criteria and 8686 patients were included after propensity score matching. Rates of major bleeding were similar in the apixaban (4.3/100 patient-years) and warfarin cohort (4.5/100 patient-years) (HR: 1.03; 95% CI: 0.76 to 1.39) during median follow-up of 4.4 months. Similar findings were observed for secondary outcomes including gastrointestinal bleeding and other bleeding, and exploratory outcomes including ischaemic stroke/systemic embolism and all-cause/CV mortality.

CONCLUSIONS

Among patients treated with amiodarone in combination with apixaban or warfarin, major bleeding and thromboembolic events were rare and with no significant difference between the treatment groups.

EUPAS REGISTRY NUMBER

EUPAS43681.

Association Between Clinical Trial Participation Status and Outcomes With Mitral Transcatheter Edge-to-Edge Repair

BACKGROUND

Clinical trials have demonstrated the efficacy and safety of mitral transcatheter edge-to-edge repair (M-TEER) for selected patients with severe mitral regurgitation. However, the generalizability of trial results to real-world patients remains uncertain.

OBJECTIVES

The authors aimed to compare baseline characteristics and in-hospital outcomes among trial participants with nonparticipants undergoing M-TEER.

METHODS

Using the National Inpatient Sample database years 2016-2020, M-TEER admissions were identified and categorized into trial participants vs none. We also identified a cohort of trial noneligible patients based on clinical exclusion criteria from pivotal trials. Multivariate regression analysis was performed to compare in-hospital outcomes. The primary outcome was in-hospital mortality, and secondary outcomes included in-hospital complications, length of stay, and hospitalization cost.

RESULTS

Among 38,770 M-TEER admissions from 2016 to 2020, 11,450 (29.5%) were trial participants, 22,975 (59.3%) were eligible nonparticipants, and 2,960 (7.6%) were noneligible. Baseline characteristics and comorbidity profiles were mostly similar between trial participants vs eligible nonparticipants. In-hospital mortality (adjusted OR [aOR]: 0.98; 95% CI: 0.60-1.62), cardiogenic shock (aOR: 1.06; 95% CI: 0.80-1.42), mechanical circulatory support (aOR: 0.91; 95% CI: 0.58-1.41), mechanical ventilation (aOR: 1.03; 95% CI: 0.74-1.42), and conversion to mitral valve surgery (aOR: 1.08; 95% CI: 0.57-2.03) were not different between both groups. Conversely, M-TEER for noneligible patients was associated with higher rates of mortality (aOR: 6.27; 95% CI: 3.75-10.45) and complications.

CONCLUSIONS

The majority of real-world M-TEER patients would have been eligible for clinical trial participation and had comparable clinical profiles and in-hospital outcomes to trial participants. However, noneligible patients had worse in-hospital outcomes compared with trial participants.