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Background: Risk stratification is critical in heart failure (HF) and the Meta-Analysis Global Group in Chronic HF (MAGGIC) score is a validated tool derived from ~40,000 patients. However, few of these patients self-identified as black, raising uncertainty regarding performance in blacks with HF., Methods and Results: This study analyzed a racially diverse group of 4046 patients (1646 black and 2400 white) from a single center from 2007 to 2015. Baseline characteristics were collected to tabulate MAGGIC score and test its discrimination and calibration within race groups. The primary end point was all-cause mortality. Death was detected using system records and the social security death master file. Discrimination was tested using Cox models of MAGGIC score stratified by race, and combined analysis including MAGGIC, race, and MAGGIC×race. Calibration was assessed using linear regression models and plots of observed versus predicted data. Overall, 901 (21%) patients died during 1-year follow-up. MAGGIC score discrimination was similar in both race groups in terms of C statistic (0.707±0.027 versus 0.725±0.014, for black versus white; P=0.556) and the hazard ratio (HR) per MAGGIC point was 1.12 in black patients (95% CI, 1.10-1.14) and 1.13 in white patients (95% CI, 1.12-1.14). Race was a significant correlate of survival, with better survival in black patients compared with white (HR, 0.66; 95% CI, 0.56-0.78), but the interaction of MAGGIC×race was not significant (β=-0.013; P=0.16), and adding race to the model did not improve discrimination (C statistic for MAGGIC versus MAGGIC+race, 0.721 versus 0.722; P=0.79). In calibration testing, the slope was not significantly different from 1 in either group, but the groups differed from each other, and it was closer to unity among black patients (0.94 versus 1.4; P=0.004)., Conclusions: These data support the use of the MAGGIC score to risk stratify black patients with HF.

Objective: This exploratory study assessed health literacy among urban African-American high school students to improve understanding of the association between adolescent health literacy and asthma., Methods: We conducted a secondary data analysis of the control group (n = 181) of the Puff City randomized controlled trial (2006-2010), a web-based intervention to promote asthma management among students, grades 9 through 12. A validated self-report 3-item health literacy screening instrument was completed at final online follow-up survey. Logistic regression was used to explore the association between health literacy, demographic characteristics, quality of life, asthma management, and health care utilization., Results: Multivariate analysis revealed that an overall inadequate health literacy score was associated with students who were more likely to be younger (OR 0.61; 95% CI 0.44-0.84), not on Medicaid (OR 0.36; 95% CI 0.17-0.76), have at least one hospitalization (OR 1.29; 95% CI 1.07-1.56); and a lower overall quality of life (OR 0.75; 95% CI 0.59-0.95). Those lacking confidence in filling out medical forms, needing help reading hospital materials, and having difficulty understanding written information were more likely to not have a rescue inhaler (OR 0.49; 95% CI 0.25-0.94), have one or more emergency visits (OR 1.21 95% CI 1.02-1.43), and one or more hospitalizations (OR 1.19; 95% CI 1.01-1.41), respectively., Conclusions: The findings indicate a significant association between inadequate health literary and suboptimal asthma management. It is important to advance understanding of adolescent health literacy, especially those at-risk, as they assume asthma self-management tasks and move toward independent adult self-care., Competing Interests: Declaration of Interest The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

Context: Metformin is considered first-line treatment for type 2 diabetes mellitus. However, little is known about its effects in African American individuals., Objective: The objective of the study was to assess whether metformin's effect on glycemic control differs by race-ethnicity Design: Electronic health records were used to identify adults who had a diagnosis of diabetes, two or more fills of metformin, and two or more glycated hemoglobin (HbA1c) measurements. Pharmacy claims were used to estimate metformin exposure based on fill frequency and dose dispensed. Regression analyses modeled the relationship between metformin exposure and HbA1c levels. Analyses were stratified by race-ethnicity and baseline HbA1c values., Setting: The study was conducted at a large health system in southeast Michigan., Main Outcome Measure: Differences in HbA1c levels while on metformin were measured., Results: We identified 19 672 patients with diabetes taking metformin; 7429 were African American and 8783 were European American. Baseline HbA1c values in these two groups were 7.81% (61.8 mmol/mol) and 7.38% (57.1 mmol/mol), respectively. Compared with no use, metformin was associated with a 0.62% (6.8 mmol/mol) reduction in HbA1c; however, there was a significant difference by race-ethnicity (P < .001). Among African American individuals, metformin use was associated with a 0.90% (9.8 mmol/mol) reduction in HbA1c levels, whereas among European Americans, metformin was associated with a 0.42% (4.6 mmol/mol) reduction. Irrespective of baseline HbA1c, metformin use was associated with lower HbA1c levels in African American individuals., Conclusions: African American individuals appear to have a better glycemic response to metformin when compared with European Americans. Further studies are needed to determine whether this translates to commensurate reductions in diabetes complications.

Background: There are large and persisting disparities in severe asthma exacerbations by race-ethnicity, and African American subjects are among those at greatest risk. It is unclear whether this increased risk solely represents differences in environmental exposures and health care or whether there is a predisposing genetic component., Objective: We sought to assess the relationship between genetic ancestry and severe exacerbations among African American subjects with asthma., Methods: Participants were part of the Study of Asthma Phenotypes and Pharmacogenomic Interactions by Race-ethnicity (SAPPHIRE). These subjects were 12 to 56 years of age, received care from a single large health system, and had a physician's diagnosis of asthma. Genetic ancestry was estimated by using a set of validated ancestry informative markers. Severe exacerbations (ie, asthma-related emergency department visits, hospitalizations, and burst oral steroid use) were prospectively identified from health care claims., Results: We assessed genetic ancestry in 392 African American subjects with asthma. The average proportion of African ancestry was 76.1%. A significant interaction was identified between ancestry and sex on severe exacerbations, such that the risk was significantly higher with increasing African ancestry among male but not female subjects. The association among male subjects persisted after adjusting for potential confounders (relative rate, 4.30 for every 20% increase in African ancestry; P = .029)., Conclusions: African ancestry was significantly and positively associated with severe exacerbations among male African American subjects. These findings suggest that a portion of the risk of asthma exacerbations in this high-risk group is attributable to a genetic risk factor that partitions with ancestry., (Copyright © 2012 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.)

Background: β-Blockers (BB) are a mainstay of heart failure (HF) treatment, yet there are inconclusive data regarding their efficacy in African American individuals., Methods and Results: We performed a retrospective study of insured patients who received care from a large health system who were hospitalized for HF between January 2000 and June 2008 and had a documented ejection fraction <50%. BB exposure was estimated over 6-month rolling windows, using pharmacy claims data. Proportional hazards regression was used to test the association between BB exposure and all-cause hospitalization or death with adjustment for baseline covariates and other HF medication exposure. We performed analyses stratified by race and overall with a BB exposure×race interaction term. A total of 1094 patients met inclusion criteria (476 white and 618 African American individuals). Median follow-up was 2.1 years. In adjusted models, BB exposure was associated with lower risk of death or hospitalization in both groups, but more so in white individuals (hazard ratio, 0.40; 95% confidence interval, 0.27, 0.60; P<0.001) compared with African American individuals (hazard ratio, 0.67; 95% confidence interval, 0.48, 0.94; P=0.024). A formal test for interaction indicated that the protection association for BB exposure differed by race (P=0.098, β=0.40). Reanalysis restricted to BBs approved for HF or HF-specific hospitalizations did not substantively alter the findings., Conclusions: BB appears to be 40-50% less effective in preventing death or hospitalization among African American patients with HF as compared with white individuals. Further study is needed to better understand BB effectiveness in African Americans with HF.

Background: African American patients disproportionately experience uncontrolled asthma. Treatment with an inhaled corticosteroid (ICS) is considered first-line therapy for persistent asthma., Objective: We sought to determine the degree to which African American patients respond to ICS medication and whether the level of response is influenced by other factors, including genetic ancestry., Methods: Patients aged 12 to 56 years who received care from a large health system in southeast Michigan and who resided in Detroit were recruited to participate if they had a diagnosis of asthma. Patients were treated with 6 weeks of inhaled beclomethasone dipropionate, and pulmonary function was remeasured after treatment. Ancestry was determined by genotyping ancestry-informative markers. The main outcome measure was ICS responsiveness defined as the change in prebronchodilator FEV(1) over the 6-week course of treatment., Results: Among 147 participating African American patients with asthma, average improvement in FEV(1) after 6 weeks of ICS treatment was 11.6%. The mean proportion of African ancestry in this group was 78.4%. The degree of baseline bronchodilator reversibility was the only factor consistently associated with ICS responsiveness, as measured by both an improvement in FEV(1) and patient-reported asthma control (P = .001 and P = .021, respectively). The proportion of African ancestry was not significantly associated with ICS responsiveness., Conclusions: Although baseline pulmonary function parameters appear to be associated with the likelihood to respond to ICS treatment, the proportion of genetic African ancestry does not. This study suggests that genetic ancestry might not contribute to differences in ICS controller response among African American patients with asthma., (Copyright © 2010 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.)

Background: Self-identified race or ethnic group is used to determine normal reference standards in the prediction of pulmonary function. We conducted a study to determine whether the genetically determined percentage of African ancestry is associated with lung function and whether its use could improve predictions of lung function among persons who identified themselves as African American., Methods: We assessed the ancestry of 777 participants self-identified as African American in the Coronary Artery Risk Development in Young Adults (CARDIA) study and evaluated the relation between pulmonary function and ancestry by means of linear regression. We performed similar analyses of data for two independent cohorts of subjects identifying themselves as African American: 813 participants in the Health, Aging, and Body Composition (HABC) study and 579 participants in the Cardiovascular Health Study (CHS). We compared the fit of two types of models to lung-function measurements: models based on the covariates used in standard prediction equations and models incorporating ancestry. We also evaluated the effect of the ancestry-based models on the classification of disease severity in two asthma-study populations., Results: African ancestry was inversely related to forced expiratory volume in 1 second (FEV(1)) and forced vital capacity in the CARDIA cohort. These relations were also seen in the HABC and CHS cohorts. In predicting lung function, the ancestry-based model fit the data better than standard models. Ancestry-based models resulted in the reclassification of asthma severity (based on the percentage of the predicted FEV(1)) in 4 to 5% of participants., Conclusions: Current predictive equations, which rely on self-identified race alone, may misestimate lung function among subjects who identify themselves as African American. Incorporating ancestry into normative equations may improve lung-function estimates and more accurately categorize disease severity. (Funded by the National Institutes of Health and others.), (2010 Massachusetts Medical Society)

Rationale: Adherence to inhaled corticosteroid (ICS) medication is known to be low overall, but tends to be lower among African-American patients when compared with white patients., Objectives: To understand the factors that contribute to ICS adherence among African-American and white adults with asthma., Methods: Eligible individuals had a prior diagnosis of asthma, one or more ICS prescriptions, and were members of a large health maintenance organization in southeast Michigan. Individuals were sent a survey that included questions about internal factors (e.g., patient beliefs, knowledge, and motivation) and external factors (e.g., socioeconomic status, barriers to care, social support, and stressors) potentially related to ICS adherence. Adherence was calculated using electronic prescription and fill data. Stepwise regression was used to identify factors associated with adherence before and after stratifying by race-ethnicity., Measurements and Main Results: Surveys were returned by 1,006 (56.3%) of 1,787 eligible patients. Adjusting for internal factors, but not external factors, diminished the relationship between race-ethnicity and ICS adherence. Among African-American patients, readiness to take ICS medication was the only internal or external factor significantly associated with ICS adherence; it explained 5.6% of the variance in adherence. Among white patients, perceived ICS necessity, ICS knowledge, doctors being perceived as the source of asthma control, and readiness to take medication were the internal factors associated with ICS adherence; these accounted for 19.8% of the variance in adherence., Conclusions: Factors associated with ICS adherence appear to differ between African-American and white patients, suggesting that group-specific approaches are needed to improve adherence.

Asthma and lead poisoning are prevalent among urban children in the United States. Lead exposure may be associated with excessive production of immunoglobulin E, possibly increasing asthma risk and contributing to racial disparities. The objective of this study was to examine racial differences in the association of blood lead level (BLL) to risk of developing asthma. We established and followed a cohort prospectively to determine asthma onset, using patient encounters and drug claims obtained from hospital databases. Participants were managed care enrollees with BLL measured and documented at 1-3 years of age. We used multiple variable analysis techniques to determine the relationship of BLL to period prevalent and incident asthma. Of the 4,634 children screened for lead from 1995 through 1998, 69.5% were African American, 50.5% were male, and mean age was 1.2 years. Among African Americans, BLL > or = 5 and BLL > or = 10 microg/dL were not associated with asthma. The association of BLL > or = 5 microg/dL with asthma among Caucasians was slightly elevated, but not significant [adjusted hazard ratio (adjHR) = 1.4; 95% confidence interval (CI), 0.7-2.9; p = 0.40]. Despite the small number of Caucasians with high BLL, the adjHR increased to 2.7 (95% CI, 0.9-8.1; p = 0.09) when more stringent criteria for asthma were used. When compared with Caucasians with BLL < 5 microg/dL, African Americans were at a significantly increased risk of asthma regardless of BLL (adjHR = 1.4-3.0). We conclude that an effect of BLL on risk of asthma for African Americans was not observed. These results demonstrate the need for further exploration of the complex interrelationships between race, asthma phenotype, genetic susceptibilities, and socioenvironmental exposures, including lead.