Race-based therapeutics

Care delivery team composition effect on hospitalization risk in African Americans with congestive heart failure

The care delivery team (CDT) is critical to providing care access and equity to patients who are disproportionately impacted by congestive heart failure (CHF). However, the specific clinical roles that are associated with care outcomes are unknown. The objective of this study was to examine the extent to which specific clinical roles within CDTs were associated with care outcomes in African Americans (AA) with CHF. Deidentified electronic medical record data were collected on 5,962 patients, representing 80,921 care encounters with 3,284 clinicians between January 1, 2014 and December 31, 2021. Binomial logistic regression assessed associations of specific clinical roles and the Mann Whitney-U assessed racial differences in outcomes. AAs accounted for only 26% of the study population but generated 48% of total care encounters, the same percentage of care encounters generated by the largest racial group (i.e., Caucasian Americans; 69% of the study population). AAs had a significantly higher number of hospitalizations and readmissions than Caucasian Americans. However, AAs had a significantly higher number of days at home and significantly lower care charges than Caucasian Americans. Among all CHF patients, patients with a Registered Nurse on their CDT were less likely to have a hospitalization (i.e. 30%) and a high number of readmissions (i.e., 31%) during the 7-year study period. When stratified by heart failure phenotype, the most severe patients who had a Registered Nurse on their CDT were 88% less likely to have a hospitalization and 50% less likely to have a high number of readmissions. Similar decreases in the likelihood of hospitalization and readmission were also found in less severe cases of heart failure. Specific clinical roles are associated with CHF care outcomes. Consideration must be given to developing and testing the efficacy of more specialized, empirical models of CDT composition to reduce the disproportionate impact of CHF.

Racial and ethnic disparities in heart failure: current state and future directions

PURPOSE OF REVIEW

This review discusses the current state of racial and ethnic inequities in heart failure burden, outcomes, and management. This review also frames considerations for bridging disparities to optimize quality heart failure care across diverse communities.

RECENT FINDINGS

Treatment options for heart failure have diversified and overall heart failure survival has improved with the advent of effective pharmacologic and nonpharmacologic therapies. With increased recognition, some racial/ethnic disparity gaps have narrowed whereas others in heart failure outcomes, utilization of therapies, and advanced therapy access persist or worsen.

SUMMARY

Racial and ethnic minorities have the highest incidence, prevalence, and hospitalization rates from heart failure. In spite of improved therapies and overall survival, the mortality disparity gap in African American patients has widened over time. Racial/ethnic inequities in access to cardiovascular care, utilization of efficacious guideline-directed heart failure therapies, and allocation of advanced therapies may contribute to disparate outcomes. Strategic and earnest interventions considering social and structural determinants of health are critically needed to bridge racial/ethnic disparities, increase dissemination, and implementation of preventive and therapeutic measures, and collectively improve the health and longevity of patients with heart failure.

Evaluation of the angiotensin II receptor blocker azilsartan medoxomil in African‐American patients with hypertension

The efficacy and safety of azilsartan medoxomil (AZL‐M) were evaluated in African‐American patients with hypertension in a 6‐week, double‐blind, randomized, placebo‐controlled trial, for which the primary end point was change from baseline in 24‐hour mean systolic blood pressure (BP). There were 413 patients, with a mean age of 52 years, 57% women, and baseline 24‐hour BP of 146/91 mm Hg. Treatment differences in 24‐hour systolic BP between AZL‐M 40 mg and placebo (−5.0 mm Hg; 95% confidence interval, −8.0 to −2.0) and AZL‐M 80 mg and placebo (−7.8 mm Hg; 95% confidence interval, −10.7 to −4.9) were significant (P≤.001 vs placebo for both comparisons). Changes in the clinic BPs were similar to the ambulatory BP results. Incidence rates of adverse events were comparable among the treatment groups, including those of a serious nature. In African‐American patients with hypertension, AZL‐M significantly reduced ambulatory and clinic BPs in a dose‐dependent manner and was well tolerated.

Difference in blood pressure response to ACE-Inhibitor monotherapy between black and white adults with arterial hypertension: a meta-analysis of 13 clinical trials

Background

Among African-Americans adults, arterial hypertension is both more prevalent and associated with more complications than among white adults. Hypertension is also epidemic among black adults in sub-Saharan Africa. The treatment of hypertension among black adults may be complicated by lesser response to certain classes of anti-hypertensive agents.

Methods

We systematically searched literature for clinical trials of ACE-inhibitors among hypertensive adults comparing blood pressure response between whites and blacks. Meta-analysis was performed to determine the difference in systolic and diastolic blood pressure response. Further analysis including meta-regressions, funnel plots, and one-study-removed analyses were performed to investigate possible sources of heterogeneity or bias.

Results

In a meta-analysis of 13 trials providing 17 different patient groups for evaluation, black race was associated with a lesser reduction in systolic (mean difference: 4.6 mmHg (95% CI 3.5-5.7)) and diastolic (mean difference: 2.8 mmHg (95% CI 2.2-3.5)) blood pressure response to ACE-inhibitors, with little heterogeneity. Meta-regression revealed only ACE-inhibitor dosage as a significant source of heterogeneity. There was little evidence of publication bias.

Conclusions

Black race is consistently associated with a clinically significant lesser reduction in both systolic and diastolic blood pressure to ACE-inhibitor therapy in clinical trials in the USA and Europe. In black adults requiring monotherapy for uncomplicated hypertension, drugs other than ACE-inhibitors may be preferred, though the proven benefits of ACE-inhibitors in some sub-groups and the large overlap of response between blacks and whites must be remembered. These data are particularly important for interpretation of clinical drug trials for hypertensive black adults in sub-Saharan Africa and for the development of treatment recommendations in this population.

Antihypertensive and metabolic effects of Angiotensin receptor blocker/diuretic combination therapy in obese, hypertensive African American and white patients

A clinical trial showed comparable blood pressure (BP) lowering by valsartan/hydrochlorothiazide and amlodipine/hydrochlorothiazide in obese hypertensive patients. Relative to amlodipine/hydrochlorothiazide, valsartan/hydrochlorothiazide reduced the hyperglycemic response to glucose challenge. An objective of this post hoc analysis was to determine whether this benefit extended to African Americans and whites. Treatments (160/12.5 mg of valsartan/hydrochlorothiazide force titrated to 320/25 mg of valsartan/hydrochlorothiazide at week 4 or 12.5 mg of hydrochlorothiazide force titrated to 25 mg of hydrochlorothiazide at week 4 with 5 and 10 mg of amlodipine added at weeks 8 and 12, respectively) were administered once daily. Both treatments reduced clinic BP from baseline to all visits (P < 0.0001), regardless of race/ethnicity (126 African Americans, 212 whites). In African Americans, there were no significant between-treatment differences in clinic or ambulatory BP lowering at weeks 8 or 16. Whites responded better to valsartan/hydrochlorothiazide. In both racial/ethnic subgroups, the addition of valsartan but not amlodipine mitigated the hyperglycemic response to hydrochlorothiazide through enhanced insulin secretion. Valsartan/hydrochlorothiazide was as effective as amlodipine/hydrochlorothiazide was in reducing BP in obese, hypertensive African Americans and better than amlodipine/hydrochlorothiazide in whites. In both racial/ethnic subgroups, the addition of valsartan to hydrochlorothiazide reduced the negative metabolic effects associated with thiazide therapy.

Genes, race, and culture in clinical care: racial profiling in the management of chronic illness

Race, although an unscientific concept, remains prominent in health research and clinical guidelines, and is routinely invoked in clinical practice. In interviews with 58 primary care clinicians we explored how they understand and apply concepts of racial difference. We found wide agreement that race is important to consider in clinical care. They explained the effect of race on health, drawing on common assumptions about the biological, class, and cultural characteristics of racial minorities. They identified specific race-based clinical strategies for only a handful of conditions and were inconsistent in the details of what they said should be done for minority patients. We conclude that using race in clinical medicine promotes and maintains the illusion of inherent racial differences and may result in minority patients receiving care aimed at presumed racial group characteristics, rather than care selected as specifically appropriate for them as individuals.

An overview of the genomics of metabolic syndrome

PURPOSE

This article provides a brief overview of the diagnostic criteria and genomic risk factors for the components of metabolic syndrome (MetS).

ORGANIZING CONSTRUCTS

Contributions of cardiovascular, obesity, and diabetes genomic risk factors to the development of MetS as reported in the literature have been reviewed.

FINDINGS

The genomic risk factors for the development of MetS are strongly linked to the genomic risk factors that make up the components of the disease. Many of the cardiovascular and renal genomic risk factors for MetS development are similar to those found in the development of hypertension and dyslipidemia. Obesity may act as a master trigger to turn on the gene expression changes necessary for the other components of the disease. Studies in the genomics of type 2 diabetes show a number of overlapping genes and polymorphisms that influence both the development of diabetes and MetS.

CONCLUSIONS

Although health practitioners now have some insights into the genomics of risk factors associated with MetS, the overall understanding of MetS remains inadequate. Clinical applications based on some of the discussed genomic risk factors are being developed but are not yet available for the diagnosis and treatment of MetS.

CLINICAL RELEVANCE

A broad knowledge of the genomic contributions to disease processes will enable the clinician to better utilize genomics to assess and tailor management of patients.

Inferring ethnicity from mitochondrial DNA sequence

BACKGROUND

The assignment of DNA samples to coarse population groups can be a useful but difficult task. One such example is the inference of coarse ethnic groupings for forensic applications. Ethnicity plays an important role in forensic investigation and can be inferred with the help of genetic markers. Being maternally inherited, of high copy number, and robust persistence in degraded samples, mitochondrial DNA may be useful for inferring coarse ethnicity. In this study, we compare the performance of methods for inferring ethnicity from the sequence of the hypervariable region of the mitochondrial genome.

RESULTS

We present the results of comprehensive experiments conducted on datasets extracted from the mtDNA population database, showing that ethnicity inference based on support vector machines (SVM) achieves an overall accuracy of 80-90%, consistently outperforming nearest neighbor and discriminant analysis methods previously proposed in the literature. We also evaluate methods of handling missing data and characterize the most informative segments of the hypervariable region of the mitochondrial genome.

CONCLUSIONS

Support vector machines can be used to infer coarse ethnicity from a small region of mitochondrial DNA sequence with surprisingly high accuracy. In the presence of missing data, utilizing only the regions common to the training sequences and a test sequence proves to be the best strategy. Given these results, SVM algorithms are likely to also be useful in other DNA sequence classification applications.

Effect of ethnicity on the hypnotic and cardiovascular characteristics of propofol induction

We compared the propofol dose causing loss of verbal response and suppression of bispectral index to 50, between 50 white and 50 black patients, aged 18-65 years. Propofol was administered at 40 mg.kg⁻¹.h⁻¹ and reduced to 8 mg.kg⁻¹.h⁻¹ when bispectral index fell to 50. We recorded heart rate and mean arterial pressure for 15 min in total and calculated, for this period, maximal percentage change from baseline for each. A statistician, blinded to patient ethnicity, found mean (SD) propofol dose for loss of verbal response in white and black patients to be 1.41 (0.37) mg.kg⁻¹ and 1.16 (0.25) mg.kg⁻¹, respectively (p < 0.001). Corresponding figures for maximal percentage change in heart rate were 14.1 (12.6) % and 7.5 (14.0) % (p = 0.015). Other differences were non-significant. The dose of propofol required for loss of verbal response, but not for suppression of bispectral index to 50, is lower in black than in white patients.

Computational analysis of candidate disease genes and variants for salt-sensitive hypertension in indigenous Southern Africans

Multiple factors underlie susceptibility to essential hypertension, including a significant genetic and ethnic component, and environmental effects. Blood pressure response of hypertensive individuals to salt is heterogeneous, but salt sensitivity appears more prevalent in people of indigenous African origin. The underlying genetics of salt-sensitive hypertension, however, are poorly understood. In this study, computational methods including text- and data-mining have been used to select and prioritize candidate aetiological genes for salt-sensitive hypertension. Additionally, we have compared allele frequencies and copy number variation for single nucleotide polymorphisms in candidate genes between indigenous Southern African and Caucasian populations, with the aim of identifying candidate genes with significant variability between the population groups: identifying genetic variability between population groups can exploit ethnic differences in disease prevalence to aid with prioritisation of good candidate genes. Our top-ranking candidate genes include parathyroid hormone precursor (PTH) and type-1angiotensin II receptor (AGTR1). We propose that the candidate genes identified in this study warrant further investigation as potential aetiological genes for salt-sensitive hypertension.

Primary care physicians' attitudes regarding race-based therapies

BACKGROUND

There is little to no information on whether race should be considered in the exam room by those who care for and treat patients. How primary care physicians understand the relationship between genes, race and drugs has the potential to influence both individual care and racial and ethnic health disparities.

OBJECTIVE

To describe physicians' use of race-based therapies, with specific attention to the case of BiDil (isosorbide dinitrate/hydralazine), the first drug approved by the FDA for a race-specific indication, and angiotensin-converting enzyme (ace) inhibitors in their black and white patients.

DESIGN

Qualitative study involving 10 focus groups with 90 general internists.

PARTICIPANTS

Black and white general internists recruited from community and academic internal medicine practices participated in the focus groups.Of the participants 64% were less than 45 years of age, and 73% were male.

APPROACH

The focus groups were transcribed verbatim, and the data were analyzed using template analysis.

RESULTS

There was a range of opinions relating to the practice of race-based therapies. Physicians who were supportive of race-based therapies cited several potential benefits including motivating patients to comply with medical therapy and promoting changes in health behaviors by creating the perception that the medication and therapies were tailored specifically for them. Physicians acknowledged that in clinical practice some medications vary in their effectiveness across different racial groups, with some physicians citing the example of ace inhibitors. However, physicians voiced concern that black patients who could benefit from ace inhibitors may not be receiving them. They were also wary that the category of race reflected meaningful differences on a genetic level. In the case of BiDil, physicians were vocal in their concern that commercial interests were the primary impetus behind its creation.

CONCLUSIONS

Primary care physicians' opinions regarding race-based therapy reveal a nuanced understanding of race-based therapies and a wariness of their use by physicians.

Adherence to guideline-recommended adjunctive heart failure therapies among outpatient cardiology practices (findings from IMPROVE HF)

Although previous studies have documented adherence with certain established heart failure (HF) quality metrics in outpatient cardiology practices, the extent to which there is conformity with other evidence-based, guideline-driven quality metrics in outpatients with HF is unknown. IMPROVE HF is a prospective cohort study designed to characterize the current management of patients with chronic HF and left ventricular ejection fraction Collapse

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MESH Headings

• Aged
• Ambulatory Care/organization & administration
• Black People/statistics & numerical data
• Cardiology Service, Hospital
• Cohort Studies
• Combined Modality Therapy/statistics & numerical data
• Female
• Guideline Adherence/statistics & numerical data
• Heart Failure/diagnosis
• Heart Failure/ethnology
• Heart Failure/therapy
• Humans
• Male
• Middle Aged
• Practice Guidelines as Topic
• Practice Patterns, Physicians'/statistics & numerical data
• Registries
• Retrospective Studies
• Risk Factors
• United States
• Black or African American

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Grants Collapse

Affiliation(s)

Clyde W Yancy Baylor Heart and Vascular Institute, Baylor University Medical Center, Dallas, Texas, USA.
Gregg C Fonarow
Nancy M Albert
Anne B Curtis
Wendy Gattis Stough
Mihai Gheorghiade
J Thomas Heywood
Mark L McBride
Mandeep R Mehra
Christopher M O'Connor
Dwight Reynolds
Mary Norine Walsh

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