A retrospective analysis of data collected from the Blue Cross Blue Shield of Michigan Cardiovascular Consortium (BMC2) reveals racial disparities in 90-day readmission and mortality between Black and white patients following a percutaneous coronary intervention (PCI) procedure. Findings of the analysis were published in the American Heart Journal.
Linking clinical registry data from PCIs performed to Medicare fee-for-service claims made between January 2013 and March 2018 across 48 Michigan hospitals, Stephanie M Spehar (University of Michigan, Ann Arbor, USA) et al set out to analyse disparities in post-PCI outcomes between Black and white patients. They note that those identifying as multiple races or those other than Black or White (Asian, Native-American or Hispanic/Latinx) ethnicity were excluded (n=889, 2.9%).
Data from 29,317 patients were evaluated in the study—10.28% pertaining to Black patients and 89.72% to white patients undergoing PCI procedures. Using propensity score matching and logistic regression models, the authors estimated the probability of 90-day readmission and Cox regression to analyse post-procedure mortality. The authors also used mediation analysis to consider the level of association arbitrated by socioeconomic factors.
Although generally minimal differences were observed between groups in terms of in-hospital post-PCI process measures and outcomes, when compared with White patients, Black patients were significantly more likely to be readmitted within the 90-day discharge period when adjusting for age and gender (adjusted odds ratio [OR] 1.62, 95% CI [1.32-2.00]). Furthermore, when adjusted for age and gender, Black patients also had a much higher risk of all-cause mortality following discharge (adjusted hazard ratio [HR] 1.45, 95% CI 1.30-1.61).
Examining the results further, the authors found associations to be significantly mediated by dual eligibility (proportion mediated (PM) for readmission: 11%; mortality: 21.1%; dual eligibility and economic well-being of the patient’s community (PM for readmission: 22.3%; mortality: 43%); and dual eligibility, economic wellbeing of the community, and baseline clinical characteristics (PM for readmission: 45%; mortality: 87.8%).
The authors highlight: “Dual eligibility, community economic well-being and traditional cardiovascular risk factors” as key areas of focus when considering racial disparities in Black and white post-PCI patients. However, they warn findings should be considered in the “context of some important limitations”, pointing out that as an observational study, their analysis is subject to unmeasured confounding, as well as the exclusion of other racial minorities and biracial individuals.
Overall, their retrospective analysis identifies significant associations between race and post-discharge outcomes after PCI. Spehar and colleagues comment: “Hospitals and policymakers need to invest in programmes that not only promote prevention of disease, but also address disparities in post-acute care and outcomes”.
Moreover, the relationships between all these factors, such as wealth, community economic distress and comorbidities, are complex, interconnected and accumulate over time. Devraj Sukul notes, “in the Blue Cross Blue Shield of Michigan Cardiovascular Consortium (BMC2), a state-wide quality improvement collaborative, we have discussed these data and many of our colleagues from across the state have shared various strategies regarding how they are working to reduce health care disparities and improve the overall care of their patients.”
Their analysis highlights the necessary changes that must be made to improve post-procedural care strategies focused on tackling racial disparities in cardiovascular disease at a community and socioeconomic level. Another important step would be to better treat common risk factors in the broader community to prevent or delay the onset of coronary artery disease.
