Hypertrophic cardiomyopathy may affect black patients earlier with disparities in care
Click Here to Manage Email Alerts
Black patients with hypertrophic cardiomyopathy were often diagnosed at a younger age and were less likely to carry a sarcomere mutation compared with white patients, according to a study published in JAMA Cardiology.
In addition, black patients had a higher burden associated with functionally limited HF and experienced inequities in care.
“Cardiologists and internists caring for African Americans with left ventricular hypertrophy should consider hypertrophic cardiomyopathy as a diagnosis and refer those patients for appropriate subspecialty management,” Neal K. Lakdawala, MD, MSc, associate physician at Brigham and Women’s Hospital and assistant professor of medicine at Harvard Medical School, told Healio. “The immediate clinical implication is that underrecognition of this disease in African Americans, which can manifest as stroke and sudden death — two complications we can prevent in patients with hypertrophic cardiomyopathy.”
Registry data
Lauren A. Eberly, MD, MPH, medicine resident at Brigham and Women’s Hospital when the study was conducted and is now a cardiology fellow at the University of Pennsylvania, and colleagues analyzed data from 2,467 patients with hypertrophic cardiomyopathy from the Sarcomeric Human Cardiomyopathy Registry who were evaluated between 1989 and 2018 at seven centers in the United States. Of the patients in the study, 205 identified as black (mean age, 40 years; 63% men) and 2,262 identified as white (mean age, 46 years; 60% men).
Several composite outcomes were assessed. The ventricular arrhythmic composite endpoint was the first occurrence of resuscitated cardiac arrest, sudden cardiac death or appropriate implantable cardioverter defibrillator therapy or firing. The overall composite endpoint was cardiac transplant or left ventricular assist device implantation, atrial fibrillation, NYHA class III or IV HF, stroke, all-cause mortality or the first occurrence of any component of the ventricular arrhythmic composite endpoint.
Black patients were younger at the time of their diagnosis of hypertrophic cardiomyopathy compared with white patients (36.5 vs. 41.9 years; P < .001) and had a higher prevalence of NYHA class III or IV HF at presentation (22.6% vs. 15.8%; P < .001). In addition, compared with white patients, black patients had lower rates of genetic testing (54.1% vs. 62.1%; P = .03) and were less likely to have sarcomeric mutations (26.1% vs. 40.5%; P = .006).
Black patients were less likely to undergo invasive septal reduction therapies compared with white patients (14.6% vs. 23%; P = .007). The rates of ICD implantation did not vary among black and white patients (33.2% vs. 32%, respectively; P = .79). Incident AF occurred less often in black patients vs. white patients (17.1% vs. 26.9%; P < .001).
Black race was linked to the development of NYHA class III or IV HF (HR = 1.45; 95% CI, 1.08-1.94), which persisted after adjusting for age at diagnosis, sarcomere status, presence of obstruction, hypertension and BMI (HR = 1.97; 95% CI, 1.34-2.88).
No differences were seen in black and white patients with regard to ventricular arrhythmias (HR = 0.95; 95% CI, 0.44-2.05), stroke (4.9% vs. 3.5%, respectively; P = .43), overall composite outcome (44.4% vs. 44.3%, respectively; P > .99) and all-cause mortality (6.3% vs. 5.3%, respectively; P = .43).
Further research
Lakdawala told Healio how more research needs to be performed regarding genetics in this patient population.
“We need to better understand the genetic architecture of left ventricular remodeling in people with diverse ancestries,” he said. “One very practical and concrete step that should be taken is to increase the inclusion of patients with African ancestry in large-scale genomic sequencing studies. Although there has been recent effort to rectify the absence of non-European individuals in genomic research, we still have a lot of work to do. This is critical to improve our ability to interpret genetic test results in patients of African ancestry.”
He added the importance of delving deeper into the present disparities in black patients with hypertrophic cardiomyopathy.
“Our future direction is to orient toward identifying structural inequities in access to care that we think underlie the low frequency of African Americans in our hypertrophic cardiomyopathy cohort. We don’t have a full understanding of why it is that black patients aren’t getting to specialized HCM clinics. We don’t know if it’s due to the inability to access a health system that has those providers. We don’t know if it’s because the gatekeepers in those systems such as primary care doctors or even general cardiologists don’t recognize this genetic disease in their African American patients and therefore don’t refer them along.” – by Darlene Dobkowski
For more information:
Neal K. Lakdawala, MD, MSc, can be reached at Brigham and Women’s Hospital, 75 Francis Street, Boston, MA 02115; email: nlakdawala@bwh.harvard.edu.
Disclosures: Lakdawala reports he received personal fees from MyoKardia. Eberly reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.
Perspective
Back to Top
Khadijah Breathett, MD, MS, FACC, FAHA
There are limited data on genetic cardiomyopathies in racial/ethnic minorities. This study by Eberly and colleagues is an important work that compares a cohort of white and African American patients with hypertrophic cardiomyopathy. Although African American patients represented 8% of the cohort, significant differences were observed. Compared to white patients, African American patients developed a higher degree of symptomatic HF, were less likely to receive genetic testing, were less likely to have a positive sarcomere test for hypertrophic cardiomyopathy and less likely to receive septal ablation as treatment. This study highlights racial disparities in identifying and treating hypertrophic cardiomyopathy in the patient and their family members.
This study supports the need for additional genetic testing in racial/ethnic minorities. Until we test an adequate number of African American patients, Hispanic patients, etc., it is unlikely that we will identify the pathogenic mutations, which could be targeted for therapy and used to identify at-risk family members.
There is great opportunity to reduce racial disparities by evaluating for the signs and symptoms of hypertrophic cardiomyopathy, developing a shared decision-making model with patients and taking the guideline-directed steps in management. We are fortunate to have better technology such as cardiac MRI to help diagnose nonischemic cardiomyopathies. Genetic testing is also more readily accessible and financially affordable with most insurance beneficiaries. When insurance companies deny appropriate diagnostic or therapeutic steps, we must advocate for our patients and can refer to studies like this. These are important steps toward reaching health equity.
University of Arizona College of Medicine - Tucson
Click Here to Manage Email Alerts