The prevention of heart failure in minority communities and discrepancies in health care delivery systems

Update on diastolic heart failure or heart failure with preserved ejection fraction in the older adults

Nearly half of all heart failure (HF) patients have diastolic HF (DHF) or clinical HF with normal or near-normal left ventricular ejection fraction (LVEF). Although the terminology has not been clearly defined, it is increasingly being referred to as HF with preserved ejection fraction (HFPEF). The prevalence of HFPEF increases with age, especially among older women. Identifying HFPEF is important because the etiology, pathogenesis, prognosis, and optimal management may differ from that for systolic HF (SHF) or HF with reduced ejection fraction. The clinical presentation of HF is similar for both SHF and HFPEF. As in SHF, HFPEF is a clinical diagnosis. Once a clinical diagnosis of HF has been made, the presence of HFPEF can be established by confirming a normal or near-normal LVEF, often by an echocardiogram. HFPEF is often associated with a history of hypertension, concentric left ventricular hypertrophy, vascular stiffness, and left ventricular diastolic dysfunction. As in SHF, HFPEF is also associated with poor outcomes. While therapies with angiotensin-converting enzyme inhibitors and beta-blockers improve outcomes in SHF, there is currently no such evidence of their benefits in older HFPEF patients. In this review recent advances in the diagnosis and management of HFPEF in older adults are discussed.

Catestatin is useful in detecting patients with stage B heart failure

Screening patients with stage B heart failure(HF) may be one strategy for reducing human morbidity. To describe catestatin levels in different stages of HF and evaluate the diagnostic utility of catestatin for detecting stage B HF, we included 300 patients. Catestatin, BNP testing and echocardiogram were performed. Our studies showed catestatin decreased gradually from stage A to C. There was significant difference between stage A and B. Cutoff value for detecting stage B HF was 19.73 ng/ml for catestatin with 90% sensitivity and 50.9% specificity. These results may have implications in the new method to detect patients with stage B HF.

Metabolic syndrome in African Americans: views on making lifestyle changes

This study explores African American adults' understanding of metabolic syndrome (MetS) and their motivations for making lifestyle changes. African Americans have a greater risk for components of MetS, such as hypertension. Three focus groups were conducted with African American adults (n = 11) with MetS. Content analysis revealed five themes: Threat of Poor Health, Building Trust With Providers, Gaining Social Support, Seeking Culturally Acceptable Alternatives, and Getting on Track and Staying on Track. Lifestyle interventions for African Americans with MetS need to focus on building trust, developing self-monitoring skills, social support, and identifying low-cost/convenient opportunities for physical activity.

Medication adherence is a mediator of the relationship between ethnicity and event-free survival in patients with heart failure

BACKGROUND

Rehospitalization rates are higher in African American than Caucasian patients with heart failure (HF). The reasons for the disparity in outcomes between African Americans and Caucasians may relate to differences in medication adherence. To determine whether medication adherence is a mediator of the relationship between ethnicity and event-free survival in patients with HF.

METHODS AND RESULTS

Medication adherence was monitored longitudinally in 135 HF patients using the Medication Event Monitoring System. Events (emergency department visits for HF exacerbation, HF and cardiac rehospitalization, and all-cause mortality) were obtained by interview and hospital data base review. A series of regression models and survival analyses was conducted to determine whether medication adherence mediated the relationship between ethnicity and event-free survival. Event-free survival was significantly worse in African Americans than Caucasians. Ethnicity was a predictor of medication adherence (P=.011). African Americans were 2.57 times more likely to experience an event than Caucasians (P=.026). Ethnicity was not a predictor of event-free survival after entering medication adherence in the model (P=.06).

CONCLUSIONS

Medication adherence was a mediator of the relationship between ethnicity and event-free survival in this sample. Interventions designed to reduce barriers to medication adherence may decrease the disparity in outcomes.

B-type Natriuretic Peptide (BNP) Is Useful in Detecting Asymptomatic Left Ventricular Dysfunction in Low-Income, Uninsured Patients

Low-income, uninsured individuals with multiple cardiovascular risk factors (CRFs) are at risk of heart failure (HF). B-type natriuretic peptide (BNP) screening for asymptomatic left ventricular dysfunction (ALVD) has not been tested specifically in this group. The purposes of this study were to describe BNP levels in asymptomatic low-income, uninsured individuals with multiple CRFs and determine the correlation between BNP levels and echocardiography for identifying ALVD. Methods: This correlational study included 53 patients (age 55 ± 10 years, 83% non-White, 64% female). BNP testing and echocardiogram (ECHO) were performed. Results: Of the 30 patients (57%) diagnosed with ALVD by ECHO, 21 (40%) had diastolic and 9 (17%) systolic dysfunction. BNP levels were lower among those with normal left ventricular (LV) function (29.6 ± 24 pg/mL) than those with diastolic (80.2 ± 69 pg/mL, p = .01) and systolic dysfunction (337.1 ± 374 pg/mL, p = .009). sParticipants with BNP ≥50 pg/ mL were 5.75 times more likely to exhibit diastolic dysfunction (odds ratio [OR] = 5.75, 95% confidence interval [CI] 1.29— 25.51; p < .01) and those with BNP ≥100 pg/mL were 7.80 times more likely to have systolic dysfunction (OR = 7.8, 95% CI 1.60—37.14; p < .005) than those with lower levels. With BNP cut point of 50 pg/mL, area under the curve (AUC) was 0.82 (95% CI 0.63—1.00) with sensitivity of 88% and specificity of 67%. Conclusion: BNP is a low-cost method to detect ALVD in high-risk, uninsured, low-income individuals. Elevated BNP levels should prompt initiation of further diagnostic testing and early treatment.

A population-based analysis of the health experience of African Nova Scotians

BACKGROUND

People of African descent living in Britain and the United States have higher rates of morbidity from chronic disease than among the general population. We investigated whether the same applied to people of African descent living in a Canadian province.

METHODS

We used administrative data to calculate 10-year cumulative incidence rate ratios for the period 1996-2005 for treated circulatory disease, diabetes mellitus and psychiatric disorders in Preston (population 2425), a community of predominantly African Nova Scotians. We used data for the province of Nova Scotia as a whole as the population reference standard. We also calculated 10-year incidence rate ratios for visits to family physicians and specialists and for admissions to hospital. We compared these findings with those in 7 predominantly white communities in Nova Scotia with otherwise similar socio-economic characteristics.

RESULTS

In the province as a whole, we identified 787,787 incident cases for the 3 disease groups over the 10-year period. Incidence rate ratios for the community of interest relative to the provincial population were significantly elevated for the 3 diseases: circulatory disease (1.19, 95% CI 1.08-1.29), diabetes (1.43, 95% CI 1.21-1.64) and psychiatric disorders (1.13, 95% CI 1.06-1.20). Incidence rate ratios in the community of interest were also higher than those in the comparison communities. Visits to family physicians and specialists for circulatory disease and diabetes were similarly elevated, but the pattern was less clear for visits for psychiatric disorders and hospital admissions.

INTERPRETATION

African Nova Scotians had higher morbidity levels associated with treated disease, which could not be explained by socio-economic characteristics, recent immigration or language. Apart from psychiatric disorders, use of specialist services was consistent with morbidity. Further study is needed to investigate the relative contribution of genetic, biological, behavioural, psychosocial and environmental factors.

Blacks and whites have a similar prevalence of reduced left ventricular ejection fraction in the general population: the Dallas Heart Study (DHS)

BACKGROUND

The objective of the study was to evaluate racial differences in the prevalence of left ventricular (LV) dysfunction. Few data compare the relative frequency of reduced LV ejection fraction (EF) (LVEF) in blacks and whites. Because of the higher prevalence of risk factors for heart failure in blacks, including hypertension, obesity, and LV hypertrophy, we hypothesized that LV dysfunction would also be more common in this ethnic group.

METHODS

In the DHS, a probability-based sample of Dallas County, we performed cardiac magnetic resonance imaging on 1335 black and 858 white participants aged 30 to 67 years to measure LVEF and volumes. We compared the prevalence of reduced LV EF and distribution of ventricular volumes in the 2 ethnic groups.

RESULTS

The prevalence of a reduced LVEF, whether defined as < 50%, < 55%, or < 60%, did not appear to be different between black versus white women (P > or = .7 for each) or men (P > or = .4 for each). Similar findings were seen using a recently defined sex-specific threshold (men < 55% and women < 61%) for low EF (P = .1). Mean LV end-diastolic and end-systolic volumes indexed to body surface area were also comparable in black and white men (P > or = .3) and women (P > or = .1).

CONCLUSIONS

Despite having a higher prevalence of risk factors for heart failure, blacks as compared with whites did not have a higher prevalence of reduced LVEF in the general population.

Pacific Islanders' perspectives on heart failure management

OBJECTIVE

To identify the health beliefs, attitudes, practices, and social and family relations important in heart failure treatment among Pacific Islanders.

METHODS

Four focus groups were convened with 36 Native Hawaiians and Samoans with heart failure and their family caregivers. Thematic data analysis was used to categorize data into four domains: health beliefs and attitudes, preferred health practices, social support systems, and barriers to heart failure care.

RESULTS

Common coping styles and emotional experiences of heart failure in this population included avoidance or denial of illness, hopelessness and despair, and reliance on spiritual/religious beliefs as a means of support. Among study participants, more Samoans preferred to be treated by physicians whereas more Native Hawaiians preferred traditional Hawaiian methods of healing. Two types of social support (informational and tangible-instrumental) were identified as important in heart failure care. Barriers to heart failure care included poor knowledge of heart failure, lack of trust in physicians' care, poor physician-patient relations, finances, dietary changes, and competing demands on time.

CONCLUSION

The recruitment, retention, and adherence of Pacific Islanders to heart failure interventions is affected by an array of psychosocial and socio-cultural factors.

PRACTICE IMPLICATIONS

Interventions might be improved by offering participants accurate and detailed information about heart failure and its treatment, engaging the extended family in providing necessary supports, and providing tools to facilitate physician-patient relationships, among others, within the context of a larger socio-cultural system.

Association of race, heart failure and chronic kidney disease

Heart failure and kidney disease are two important emerging epidemics. The importance of pre-end stage kidney disease was introduced in the 2002 publication of the National Kidney Foundation's Chronic Kidney Disease Guidelines. One in nine US adults has some degree of kidney disease, many of whom also have heart failure. Among all patients with heart failure, approximately half have significant kidney disease. The distribution of etiologies of these conditions varies among races; blacks tend to have heart and kidney disease predominantly due to hypertension, while whites tend to be affected by ischemic heart disease and Hispanics by diabetic kidney disease. The burden of disease is disproportionately borne by minorities, the cause of which remains to be fully elucidated. The bulk of knowledge of these diseases is based on studies involving predominantly white subjects. Recent studies have suggested that there are racial differences in patients' responsiveness to various classes of drugs. Designs of future studies should take into account these differences.