Minding the Gaps: Race and Sex Disparities in Rehospitalization Post-MI Might Be Due to Angina, Depression

Research continues to show worse outcomes in women compared with men in terms of rehospitalization after acute MI, with further implications for patients based on race as well.

As an often-used marker for quality of care, hospital readmissions have been tracked carefully through a variety of registries, but no definitive data have emerged regarding which cardiac patients are at highest risk. However, numerous studies have shown care discrepancies and worse outcomes in women compared to men and in black compared to white individuals.

Looking at more than 11,500 patients enrolled in the TRANSLATE-ACS study, researchers led by Connie Hess, MD (University of Colorado School of Medicine, Aurora), found that while 20.6% of MI patients treated with PCI report angina within 1 year of hospital discharge, black and female patients were more likely to report it and be rehospitalized. Rates of unplanned rehospitalization at 1 year were highest among black (44.1%) and white (38.4%) female patients, with black male patients (36.4%) also being readmitted more than white male patients (30.2%; P < 0.0001 for trend).

Additionally, compared to white patients, black patients were more likely to report angina at 6 weeks regardless if they were female (44.2% vs 31.8%; P < 0.0001) or male (33.5% vs 27.1%; P < 0.0001).

Compared to white patients, black patients had a greater burden of comorbidities and socioeconomic hardship, and they were also more likely to be treated with BMS and less likely to be referred for cardiac rehab.

An overarching implication of this study, published in the February 7, 2017, issue of Circulation, the authors write, is that their 20.6% overall rate of 1-year angina is comparable with the 19.9% seen in a smaller study conducted between 2003 and 2005, “highlighting the lack of progress over the past decade in addressing this issue.” Reducing angina after MI, Hess and colleagues add, “may also improve downstream health outcomes, and our findings lend support to recent efforts advocating for the consideration of patient health status . . . as both a cardiovascular risk factor and a health outcome in and of itself.”

As for the sex and race disparities highlighted here, the authors suggest an emphasis on increasing cardiac rehab referral rates perhaps through “automatic referral mechanisms.” It will also be the responsibility of public health officials to correct the “false self-perceptions about lower cardiovascular risk” in women and minorities, they write.

More Readmissions for Women of All Ages

In a second study also published in Circulation, Rachel Dreyer, PhD (Yale University School of Medicine, New Haven, CT), and colleagues also looked at sex differences in rehospitalization after acute MI. Prospectively looking at about 3,500 patients from 24 US centers enrolled in the TRIUMPH study, they found that women were 29% more likely than men to be readmitted to the hospital for any reason within one year of their MI (HR 1.29; 95% CI 1.12-1.48). Even after adjustment for demographics and clinical factors, women were still 26% more likely than men to be rehospitalized. Only adjustment for health status and psychosocial factors attenuated this risk. Age was not found to impact risk of rehospitalization.

“We have provided confirmatory evidence that a sex disparity exists for 1-year rehospitalization, whereby women of all age groups are at higher risk compared with men of similar age,” Dreyer and colleagues write. “In addition, our study highlights that the increased risk observed in women may be explained by a complex interplay of multiple factors.”

Future research should focus on the link between health status and depression and readmission, they suggest. Additionally, “moving forward, an opportunity may present itself to design sex-based interventions to improve care for patients after discharge over the first year after AMI, including interventions in women that aim to improve health status and psychosocial well-being,” the authors conclude.

Moving Beyond the Gaps

The race and sex discrepancies highlighted in these studies “is not a novel message,” Tracy Wang, MD, MHS, MSc (Duke University Medical Center, Durham, NC), senior author of the first study, told TCTMD in an email. “We keep hoping that these gaps will narrow to a point that we no longer have to keep pointing them out, but sadly that is still not the case.”

We keep hoping that these gaps will narrow to a point that we no longer have to keep pointing them out, but sadly that is still not the case. Tracy Wang

However, both of these studies stand out because the go “beyond population differences . . . to get at the ‘why,’” she observed.  For example, “knowing that angina burden is more frequent among black patients and female patients helps us understand why these patients are rehospitalized more frequently, but more importantly, it gives us something to work with. If we use cardiac rehab or antianginal medications to reduce symptom burden, we will actually be able to change these stats.”

It may be common sense that inherent biological and demographic differences will impact life after MI for patients from different backgrounds, Wang said, but clinicians won’t know about “likelihood of symptom recurrence, quality of life, physical function, [and] depression” unless they ask. “These studies tell us that these questions are particularly important to ask of our female patients, because understanding these factors allows us to tailor more effective care,” she added.

“Fundamentally, I hope we start moving away from conversations about race and gender gaps, and moving more towards a dialogue on reducing patient risk,” Wang concluded. With the knowledge that angina and depression can explain some of the observed race and sex discrepancies, “our next studies should test the impact of interventions on these patient-centered outcomes, and then confirm for us that by acting on these outcomes, we are also closing the gaps.”