Abstract

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.

Introduction

Clinical trials are essential drivers in improvements around delivery of quality of care in medicine, playing an important role in the provision of evidence for clinical guidelines (1,2).

Patient participation in clinical trials may be associated with better provision of care and improved clinical outcomes (3). A recent study revealed that trial participants are more likely to receive invasive management and have better outcomes during an index hospitalization for acute coronary syndrome (ACS) (4). Similarly, other studies have shown that trial-participating ACS patients were more likely to receive invasive management strategies or guideline-directed medications during acute stay (French Registry on Acute ST-elevation or non-ST-elevation myocardial infarction (FAST-MI) and Global Registry of Acute Coronary Events (GRACE)) (5,6). Another analysis of the National Cardiovascular Data Registry (NCDR) also suggested that ACS patients admitted to trial-participating hospitals more often receive guideline-directed management (7).

However, it was unknown whether these findings translate to the post-discharge period and whether trial participation has an association with unplanned 30-day readmissions, an important quality metric. Unplanned 30-day readmissions reflect the quality of care provided during in-hospital stay and are directly related to an unnecessary cost burden to the healthcare system (8).

Therefore, using a national United States (US) administrative dataset, the present study aimed to investigate the rates, causes and outcomes of readmission in a representative ACS population based on their trial participation status. Furthermore, this study explored the predictors of readmission based on the trial participation status.

Section snippets

Methods

The National Readmission Database (NRD) is part of the Healthcare Cost and Utilization Project (HCUP) registries that were developed by the Agency for Healthcare Research and Quality (AHRQ). It comprises publicly available, anonymized patient discharges with and without repeat hospital visits in a year, including >7 million hospitalizations yearly, representing one of the largest healthcare databases of routinely collected data US. The dataset includes discharge weights for producing national

Results

A total of 2,066,328 admissions with a principal diagnosis of ACS were included in the study, out of which there were 4061 trial participants (0.2 %) and 2,062,266 non-participants (99.8 %). Of these, 189,240 (9.2 %) cases experienced an unplanned 30-day readmission. Within the readmitted cohort, there were 398 (0.2 %) trial participants and 188,842 (99.8 %) non-participants (Supplementary Table 2). Rates of unplanned 30-day readmission were not different, with 9.2 % in the non-participants and 

Discussion

The present national analysis reports important data on the association of trial participation with causes and rates of unplanned 30-day readmission rates among patients hospitalized for ACS. Unplanned 30-day readmissions represent an important quality metric that reflects management and care during index hospitalization. Although prior data suggests trial participation-based disparities of ACS patients during the index admission, it was unknown whether these findings translate to the

Conclusions

In conclusion, ACS patients are at high-risk for unplanned 30-day readmissions. There was no significant difference in unplanned 30-day readmission rates after ACS between trial participants and non-participants, but non-participants were more likely to have cardiovascular readmission. There was no difference in all-cause in-hospital mortality during readmission episode between trial participants and non-participants, but trial participants showed higher occurrence of major bleeding and stroke

Disclosure

All authors take responsibility for all aspects of the reliability and freedom from bias of the data presented and their discussed interpretation.

Funding

None.

CRediT authorship contribution statement

Andrija Matetic: Writing – review & editing, Writing – original draft, Visualization, Validation, Software, Methodology, Formal analysis, Data curation, Conceptualization. Adrian Kuchtaruk: Software, Methodology, Formal analysis, Data curation. Zbigniew Siudak: Writing – review & editing, Validation, Supervision. Waqas Ullah: Writing – review & editing, Validation. Ayman Elbadawi: Writing – review & editing, Validation. Islam Y. Elgendy: Writing – review & editing, Validation. Sarah Zaman:

Declaration of competing interest

None.

Acknowledgments

None.

[Best Women Cardiologist in India, Best Female Cardiologist in India, Cardiologist]