Shock in Peripartum Cardiomyopathy Especially Risky in Black, Hispanic Patients

Black and Hispanic women with peripartum cardiomyopathy (PPCM) during or shortly after pregnancy are more likely to develop cardiogenic shock than white women, and when they do, they face much higher in-hospital mortality, a new study shows.

The analysis of nationwide US data, spanning from 2005 to 2019, also highlights disparities in sociodemographic factors, comorbidities, and management. Potential explanations include differences in income level, insurance, access to care, and disease severity, among other factors.

“Multiple studies have shown that Black women are more likely to develop peripartum cardiomyopathy in pregnancy and also they’re more likely to die compared to both white and Hispanic women,” Titilope Olanipekun, MD, MPH (Covenant Health System, Knoxville, TN, and Morehouse School of Medicine, Atlanta, GA), told TCTMD.

While cardiogenic shock is a known complication of PPCM, there’s been a “knowledge gap” about the interplay between race/ethnicity and outcomes among women facing this scenario, he said. “That’s something that has not been looked into.”

The study, with Olanipekun and Temidayo Abe, MD (Vanderbilt University Medical Center, Nashville, TN, and Morehouse School of Medicine), as co-lead authors, was published online recently in JAMA Network Open.

Commenting on the results for TCTMD, Khadijah Breathett, MD (Indiana University School of Medicine, Indianapolis), said that they fall into a long line of research revealing that healthcare is not meeting the needs of all patients. “It’s sad. It’s unfortunate. It solidifies a lot of the other, prior data” showing not only race/ethnicity but also gender can sway decision-making in advanced heart failure, she said.

Although observational analyses aren’t able to speak to the “why,” she continued, studies by her and others have explored how clinicians’ own biases can impact treatment choices, in part based on doubts about social support and the ability of patients to adhere to therapy. This is especially true in situations “where we have to deal with both types of ‘isms’—racism and sexism—and it’s entirely possible this could contribute to the findings,” said Breathett. “It’s definitely disheartening to see [these results] and it shows the level of work that’s needed to achieve equitable care.”

This report “illustrates we as a healthcare system have a lot of work to do,” she said. “As cardiologists, cardiothoracic surgeons, and advanced practice providers, we have to start to consider how our decision-making may unfairly impact a person based on their race or their gender.”

National Inpatient Sample, 2005-2019

For their retrospective cohort study, the researchers used the National Inpatient Sample to identify 55,804 women hospitalized with PPCM between 2005 and 2019. Among them, 1,945 had cardiogenic shock, with a mean age of 31 years. Nearly half (49%) were Black, 39% white, and 12% Hispanic.

There were 39 cases of cardiogenic shock per 1,000 Black and Hispanic women and 33 cases per 1,000 white women (P < 0.001). Incidence grew over the study period, reaching rates of 50, 60, and 52 events per 1,000 Black, Hispanic, and white women, respectively. Adjusted for confounders, the likelihood of cardiogenic shock remained higher in both Black patients (OR 1.17; 95% CI 1.15-1.57) and Hispanic patients (OR 1.37; 95% CI 1.17-1.59).

As cardiologists, cardiothoracic surgeons, and advanced practice providers, we have to start to consider how our decision-making may unfairly impact a person based on their race or their gender. Khadijah Breathett

Medicaid insurance was more common for Black (54.8%) and Hispanic (50.4%) patients than it was for white patients (46.1%). Black and Hispanic patients also were more likely to lack insurance entirely (6.4% in each group vs 1.3% of white patients), and to have a lower household income. Chronic kidney disease (CKD), diabetes, obesity, and hypertensive disorders of pregnancy were more frequently seen in the Black and Hispanic groups, while Hispanic women were most likely to have antepartum hemorrhage, Black women to have chronic hypertension and hyperlipidemia, and white women to have polysubstance use.

There were significant variations in mechanical circulatory support (MCS) use even when accounting for age, insurance, income, comorbidities, and disease-related factors. Hispanic women were more likely than white women to receive any MCS device (OR 2.23; 95% CI 1.60-3.09), an intra-aortic balloon pump (OR 1.65; 95% CI 1.11-2.44), or a ventricular assist device (OR 4.45; 95% CI 2.45-8.08). Black women also were more likely to receive a ventricular assist device (OR 2.69; 95% CI 1.63-4.42).

Yet heart transplantation was less common for both Black patients (OR 0.51; 95%CI 0.33-0.78) and Hispanic patients (OR 0.15; 95% CI 0.06-0.42).

In-hospital mortality was heightened among Hispanic and Black women, as well, reaching 20.8% and 17.9%, respectively, compared with 10.1% in white women. Adjusted for confounders, Black patients and Hispanic patients still were more likely to die.

In-Hospital Mortality Risk vs White Women

Other factors linked to higher mortality were CKD, diabetes, obesity, antepartum hemorrhage, and use of MCS. Higher household income, on the other hand, was associated with lower mortality.

“Based on previous studies, we know that Hispanic women, compared to Black pregnant women, are less likely to develop peripartum cardiomyopathy,” Olanipekun said. What came as a surprise was to see that, once PPCM did occur, Hispanic women were just as likely to develop cardiogenic shock as Black women and faced the highest mortality risk.

But Why?

There are some hints as to what’s driving the disparate outcomes, the researchers say. “We found higher mortality odds in the subgroups of Black and Hispanic patients with lower median income, CKD, obesity, and diabetes, which further substantiate the positive correlation between low socioeconomic status and higher cardiovascular comorbidity burden and poorer outcomes, including mortality in patients with cardiogenic shock.”

It’s unclear what led to the differences in treatment.

MCS tends to be directed at the sickest patients, Olanipekun pointed out. It’s possible “that a lot of the Black and Hispanic women that did receive mechanical support devices were so sick that the devices did not improve outcomes,” he said, adding that data are mixed on whether this extra support works. “It’s sometimes helpful, it’s sometimes not helpful.”

Prior research also has shown that Black and Hispanic women are less likely to receive a heart transplant, Olanipekun added, but their data set doesn’t allow a granular look at what factored into the decision of whether or not to place patients on the waiting list for a donated organ. “Generally, when it comes to heart transplant you tend to select the patients that you think may benefit the most,” he noted.

Maternal cardiovascular health has been an area of increasing focus in recent years, becoming headline news after the undoing of Roe v. Wade.

It’s time to step up and “recognize that something needs to change,” Breathett urged. “There’s no such thing as an innocent bystander. If these things are happening, the onus is on the clinician to speak up about it, to consider: why aren’t we offering these different therapies to women of color?”

Many of these problems are on a policy level and “systemic, with multiple components that need to be addressed,” Olanipekun said, adding, however, that clinicians can remain vigilant. “When you see pregnant women who are Hispanic or Black, be aware of these traditional risk factors that may complicate outcomes down the line,” he advised, as this may facilitate better risk-stratification of these patients. It’s also important to educate patients about why they need to keep an eye on these risk factors, follow up with their physicians, and follow their recommendations, Olanipekun added.