Update on disparities in the pathophysiology and management of hypertension: focus on African Americans

Ethnic Disparities in Thrombotic and Bleeding Diatheses Revisited: A Systematic Review of Microsurgical Breast Reconstruction across the East and West

BACKGROUND

 Ethnicity has been shown to play a role in disparate coagulative responses between East Asian and Caucasian patients undergoing nonmicrovascular surgery. In this study, we sought to further investigate this hematologic phenomenon between the two ethnic groups within the field of microsurgical breast reconstruction.

METHODS

 A systematic review examining the reported incidence of microvascular thrombosis and all-site bleeding among breast free flaps in East Asians and Westerners was performed. Statistical analysis was performed using the chi-square test.

RESULTS

 Ten East Asian studies with 581 flaps and 99 Western studies with 30,767 flaps were included. A statistically significant higher rate of thrombotic complications was found in Westerners compared with East Asians (4.2 vs. 2.2%, p = 0.02). Conversely, bleeding events were more common in East Asians compared with Westerners (2.6 vs. 1.2%, p = 0.002).

CONCLUSION

 There appears to be an ethnicity-based propensity for thrombosis in Westerners and, conversely, for bleeding in East Asians, as evident by the current systematic review of microvascular breast reconstruction data. It is therefore advisable to consider ethnicity in the comprehensive evaluation of patients undergoing microsurgical procedures.

Management of Essential Hypertension

The treatment of essential hypertension is one of the most critical interventions to decrease cardiovascular morbidity and mortality. The prevalence of hypertension in the US varies across race/ethnicity with African Americans having the highest prevalence and overall less control among racial/ethnic minorities compared with non-Hispanic whites. Therapeutic lifestyle modifications are the bedrock of essential hypertension control, but most patients with hypertension will require pharmacotherapy, usually with multiple medications often in combination. Overall, the principal drug classes recommended as initial pharmacotherapy are thiazide-type diuretics, calcium channel blockers, and angiotensin-converting enzyme inhibitors or angiotensin receptor blockers.

The Association of Neighborhood Gene-Environment Susceptibility with Cortisol and Blood Pressure in African-American Adults

BACKGROUND

African-American adults are disproportionately affected by stress-related chronic conditions like high blood pressure (BP), and both environmental stress and genetic risk may play a role in its development.

PURPOSE

This study tested whether the dual risk of low neighborhood socioeconomic status (SES) and glucocorticoid genetic sensitivity interacted to predict waking cortisol and BP.

METHODS

Cross-sectional waking cortisol and BP were collected from 208 African-American adults who were participating in a follow-up visit as part of the Positive Action for Today's Health trial. Three single-nucleotide polymorphisms were genotyped, salivary cortisol samples were collected, and neighborhood SES was calculated using 2010 Census data.

RESULTS

The sample was mostly female (65 %), with weight classified as overweight or obese (M BMI = 32.74, SD = 8.88) and a mean age of 55.64 (SD = 15.21). The gene-by-neighborhood SES interaction predicted cortisol (B = 0.235, p = .001, r (2) = .036), but not BP. For adults with high genetic sensitivity, waking cortisol was lower with lower SES but higher with higher SES (B = 0.87). Lower neighborhood SES was also related to higher systolic BP (B = -0.794, p = .028).

CONCLUSIONS

Findings demonstrated an interaction whereby African-American adults with high genetic sensitivity had high levels of waking cortisol with higher neighborhood SES, and low levels with lower neighborhood SES. This moderation effect is consistent with a differential susceptibility gene-environment pattern, rather than a dual-risk pattern. These findings contribute to a growing body of evidence that demonstrates the importance of investigating complex gene-environment relations in order to better understand stress-related health disparities.

Social Determinants of Racial Disparities in CKD

Significant disparities in CKD rates and outcomes exist between black and white Americans. Health disparities are defined as health differences that adversely affect disadvantaged populations, on the basis of one or more health outcomes. CKD is the complex result of genetic and environmental factors, reflecting the balance of nature and nurture. Social determinants of health have an important role as environmental components, especially for black populations, who are disproportionately disadvantaged. Understanding the social determinants of health and appreciating the underlying differences associated with meaningful clinical outcomes may help nephrologists treat all their patients with CKD in an optimal manner. Altering the social determinants of health, although difficult, may embody important policy and research efforts, with the ultimate goal of improving outcomes for patients with kidney diseases, and minimizing the disparities between groups.

Impact of Cardiovascular Risk Factors on Graft Outcome Disparities in Black Kidney Transplant Recipients

Although outcome inequalities for non-Hispanic black (NHB) kidney transplant recipients are well documented, there is paucity in data assessing the impact of cardiovascular disease (CVD) risk factors on this disparity in kidney transplantation. This was a longitudinal study of a national cohort of veteran kidney recipients transplanted between January 2001 and December 2007. Data included baseline characteristics acquired through the United States Renal Data System linked to detailed clinical follow-up information acquired through the Veterans Affairs electronic health records. Analyses were conducted using sequential multivariable modeling (Cox regression), incorporating blocks of variables into iterative nested models; 3139 patients were included (2095 non-Hispanic whites [66.7%] and 1044 NHBs [33.3%]). NHBs had a higher prevalence of hypertension (100% versus 99%; P<0.01) and post-transplant diabetes mellitus (59% versus 53%; P<0.01) with reduced control of hypertension (blood pressure <140/90 60% versus 69%; P<0.01), diabetes mellitus (A1c <7%, 35% versus 47%; P<0.01), and low-density lipoprotein (<100 mg/dL, 55% versus 61%; P<0.01). Adherence to medications used to manage CVD risk was significantly lower in NHBs. In the fully adjusted models, the independent risk of graft loss in NHBs was substantially reduced (unadjusted hazard ratio, 2.00 versus adjusted hazard ratio, 1.49). CVD risk factors and control reduced the influence of NHB race by 9% to 18%. Similar trends were noted for mortality, and estimates were robust across in sensitivity analyses. These results demonstrate that NHB kidney transplant recipients have significantly higher rates of CVD risk factors and reduced CVD risk control. These issues are likely partly related to medication nonadherence and meaningfully contribute to racial disparities for graft outcomes.

Sleep as a potential fundamental contributor to disparities in cardiovascular health

Optimal sleep is integral to health but is commonly not obtained. Despite its wide-ranging public health impact, sleep health is considered only rarely by policy makers, employers, schools, and others whose policies and structures can adversely affect sleep. An inadequate duration of sleep and poor-quality sleep are prevalent in minority and low-income populations, and may be fundamental to racial and socioeconomic status inequities that contribute to a range of health conditions, including cardiovascular disease (CVD). This review examines the relationship between sleep and disparities in CVD. We describe the public health importance of sleep and the role of sleep duration, as well as the two most common disorders (sleep apnea and insomnia) as risk factors for a number of chronic diseases. We use a multilevel model focused on population health and health disparities, which is based on the notion that individual behaviors, such as sleep, are influenced by complex and dynamic interrelations among individuals and their physical and social environments. We also describe modifiable factors that contribute to insufficient sleep and circadian misalignment, propose potential interventions in various sectors (e.g., neighborhoods, schools, workplaces) that can address social structures that contribute to disparities, and recommend areas for future research. Integrating sleep into public health research will identify novel approaches for closing gaps in health disparities.

Multilevel Associations of Neighborhood Poverty, Crime, and Satisfaction With Blood Pressure in African-American Adults

BACKGROUND

African-American adults experience the highest rates of elevated blood pressure (BP), and this disparity may be linked to socioeconomic and neighborhood-related disadvantage. Based on a bioecological stress-buffering framework, relations of poverty and neighborhood environmental perceptions with BP were assessed using multilevel regression in at-risk African-American adults.

METHODS

This cross-sectional study used baseline data that were collected in 2008 as part of the Positive Action for Today's Health (PATH) trial (N = 409), a community-based intervention to increase walking in low-income, high-crime neighborhoods. BP and perceived neighborhood crime and satisfaction were investigated as individual-level indicators of health and neighborhood environment. Census block groups (N = 22) served as geographic proxies for neighborhoods, and poverty was obtained using 2010 U.S. Census data, to characterize the neighborhood-level socioeconomic environment.

RESULTS

There were no individual-level direct associations. Significant cross-product interactions demonstrated that with higher perceived crime, high satisfaction was associated with lower systolic (γ = 3.34) and diastolic (γ = -1.37) BP, but low satisfaction was associated with higher systolic (γ = 15.12) and diastolic (γ = 7.57) BP. Neighborhood-level poverty was associated with diastolic (γ = 11.48, SE = 4.08, P = 0.008) and systolic BP (γ = 12.79, SE = 6.33, P = 0.052). Variance in BP across block groups was low (intraclass correlation coefficients = 0.002-0.014) and there were no significant random effects.

CONCLUSIONS

Results supported hypotheses, with greater neighborhood satisfaction linked to lower systolic and diastolic BP when perceived crime was high. Neighborhood poverty was also linked to higher systolic and diastolic BP. Prevention efforts should further investigate whether attending to issues of poverty and related neighborhood perceptions reduces high BP in at-risk African-American communities.

Social support buffering of the relation between low income and elevated blood pressure in at-risk African-American adults

Socioeconomic disadvantage has been linked to elevated blood pressure (BP), and the purpose of this study was to assess whether interpersonal social supports buffer these adverse relations in African-American adults. In three communities matched demographically, a subsample of participants (N = 204) of the Positive Action for Today's Health trial provided measures of perceived social support, annual household income, and BP. Multiple regression analyses with cross-product interactions were conducted using follow-up data. The sample had a mean age of 52.8 years (SD = 15.1), and was predominantly female (66 %) with a high body mass index (M = 33.5, SD = 14.7). Results indicated an inverse relation between social support and diastolic BP (B = -.178, p = .005), and also an interaction with income (p = .046), such that higher social support related to lower diastolic BP in the lowest-income individuals (B = -1.05). The same direct (B = -.141, p = .025) and interacting (B = -1.42, p = .040) social support effects were present for systolic BP, however the omnibus model for systolic BP was not significant, F(6, 196) = 1.80, p = .09. The hypothesized buffering effect of social support on the adverse relation of income to BP was partially supported in at-risk African-American adults. Future prevention efforts for reducing the impact of socioeconomic stress on BP may aim to increase perceptions of social support.

Decomposing Black-White Disparities in Heart Disease Mortality in the United States, 1973-2010: An Age-Period-Cohort Analysis

Against the backdrop of late 20th century declines in heart disease mortality in the United States, race-specific rates diverged because of slower declines among blacks compared with whites. To characterize the temporal dynamics of emerging black-white racial disparities in heart disease mortality, we decomposed race-sex-specific trends in an age-period-cohort (APC) analysis of US mortality data for all diseases of the heart among adults aged ≥35 years from 1973 to 2010. The black-white gap was largest among adults aged 35-59 years (rate ratios ranged from 1.2 to 2.7 for men and from 2.3 to 4.0 for women) and widened with successive birth cohorts, particularly for men. APC model estimates suggested strong independent trends across generations ("cohort effects") but only modest period changes. Among men, cohort-specific black-white racial differences emerged in the 1920-1960 birth cohorts. The apparent strength of the cohort trends raises questions about life-course inequalities in the social and health environments experienced by blacks and whites which could have affected their biomedical and behavioral risk factors for heart disease. The APC results suggest that the genesis of racial disparities is neither static nor restricted to a single time scale such as age or period, and they support the importance of equity in life-course exposures for reducing racial disparities in heart disease.

Health Behavior Decision-making in African-American Adults Diagnosed with Schizophrenia

Little is known about the factors that influence health behavior decision-making among people with schizophrenia. The purpose of this qualitative study was to describe the processes used by 10 African-American adults with schizophrenia when making health behavior decisions and identification of perceived barriers and facilitators to health. Three phases of health behavior decision-making were identified: Recognizing Complex Components of Health, Personalizing Components of Health, and Tracking Health Status. Findings may guide clinicians' efforts to improve the health status of patients, as well as influence future research in understanding health behavior decision-making among vulnerable populations.

Hypertension in minority populations: new guidelines and emerging concepts

Persistent disparities in hypertension, CKD, and associated cardiovascular disease have been noted in the United States among racial/ethnic minority groups. Overall, these disparities are largely mediated by social determinants of health. Yet, emerging data suggest additional biologic factors in racial/ethnic disparities in hypertension prevalence, complications, particularly CKD, and responses to treatment. Nevertheless, race is a social construct and not a physiologic concept, and ethnicity, federally defined as the binary "Hispanic/Latino" or "not Hispanic/Latino," is also imprecise. However, race/ethnicity categories may help interpret health-related data, including surveillance and research, and are important in ensuring that clinical trials remain generalizable to diverse populations. There is significant heterogeneity among prespecified groups and, perhaps, greater genetic differences within than between certain racial/ethnic groups. This review will explore hypertension epidemiology, pathophysiology, and management among the diverse and growing US minority groups, specifically African Americans and Hispanics because much less data are available across the wide spectrum of diverse populations. We will highlight the intersection of hypertension and increasingly prevalent CKD, particularly in African Americans. Finally, we propose multidimensional treatment approaches to hypertension among diverse populations, encompassing population, community, health system, and individual-based approaches.

Blood pressure control and perceived health status in African Americans with subclinical hypertensive heart disease

The role of antihypertensive therapy in reducing the risk of cardiovascular complications such as heart failure is well established, but the effects of different blood pressure goals on patient-perceived health status has not been well defined. We sought to determine if adverse effects on perceived health status will occur with lower blood pressure goals or more intensive antihypertensive therapy. Data were prospectively collected as a part of a single center, randomized controlled trial designed to evaluate standard (Seventh Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure-compliant) versus intense (<120/80 mm Hg) blood pressure goals for patients with uncontrolled hypertension and subclinical hypertensive heart disease. Blood pressure management was open label, and health status was measured at 3-month intervals over 1 year of follow-up using the short-form (SF)-36. Mixed linear models were constructed for each of the SF-36 summary scores. One hundred twenty-three (mean age 49.4 ± 8.2; 65% female; 95.1% African American) patients were randomized, 88 of whom completed the protocol. With the exception of a decrease in perceived health transition, health status did not change significantly on repeat measurement. Lower blood pressure goals and more intensive antihypertensive therapy appear to be well tolerated with limited effects on patients' perception of health status.

Disparities in antihypertensive medication adherence in adolescents

BACKGROUND

Hypertension affects up to 5 % of all children, but little is known about the role of medication adherence on blood pressure (BP) control. In this study we examined the association between adolescents' antihypertensive medication adherence and BP control, investigating for racial disparities.

METHODS

A total of 21 adolescents with essential hypertension [mean age 14.7 ± 2.0 years, 57 % male, 52 % African American] were recruited from a pediatric nephrology clinic. Objective medication adherence measures were obtained with Medication Event Monitoring System (MEMS) caps and pharmacy refill records to determine medication possession ratios (MPRs).

RESULTS

The African Americans adolescents had lower medication adherence than non-African Americans adolescents based on the MPR over the past 12 months (mean 0.54 ± 0.21 vs. 0.85 ± 0.16, respectively; p < 0.001) and a trend for less adherence measured by MEMS caps over the last 28 days (mean 0.75 ± 0.26 vs. 0.91 ± 0.04, respectively; p < 0.07). Seven of the eight participants with low adherence (MPR <0.65) had uncontrolled BP (systolic and/or diastolic BPs ≥ 95th percentile), and no participants with high adherence according to the MPR had uncontrolled BP (p < 0.001). There was no difference in BP control by race.

CONCLUSIONS

Antihypertensive medication adherence measured by pharmacy refills was associated with BP control. AAs were more likely to have lower medication adherence. Targeting medication adherence through the use of electronic medical records may be a potential mechanism to reduce health disparities.

Associations among environmental supports, physical activity, and blood pressure in African-American adults in the PATH trial

High blood pressure disproportionately affects African-American adults and is a leading cause of stroke and heart attack. Engaging in recommended levels of physical activity reduces blood pressure, and social and physical environmental supports for physical activity may increase engagement in physical activity. Based on social cognitive theory within a bioecological framework, the present study tested hypotheses that perceived peer social support for physical activity and neighborhood walkability would be positively associated with physical activity, and that physical activity would mediate their relation with blood pressure. Baseline data were collected with 434 African-American adults in underserved communities (low income, high crime) participating in the Positive Action for Today's Health (PATH) trial. Perceived peer social support for physical activity and neighborhood walkability were measured with validated surveys. Physical activity was assessed with 7-day accelerometry (moderate-to-vigorous physical activity, min/day) and with a 4-week recall of walking. Three blood pressure assessments were taken by trained staff using standard protocols, with values from the second and third assessments averaged. The sample was predominantly female (63%), overweight (mean body mass index = 30.9, SD = 8.4), and had slightly elevated blood pressures with a mean systolic blood pressure of 132.4 (SD = 17.9) and a mean diastolic blood pressure of 81.4 (SD = 11.0). Results demonstrated that peer social support for physical activity (B = 2.43, p = .02) and neighborhood walkability (B = 2.40, p = .046) were significantly related to average daily moderate-to-vigorous physical activity. Neighborhood walkability was also significantly associated with self-reported average daily walking (B = 8.86, p = .02). Physical activity did not mediate their relation with blood pressure and no significant direct effects of these variables on blood pressure were found. The positive influence of social and physical environmental supports on physical activity in underserved African-American communities may guide intervention efforts and contribute to our understanding of physical activity and related health outcomes.

Disparities in amputations in minorities

BACKGROUND

As a result of the impact of health disparities on the healthcare system such as their influence on arenas significant to healthcare distribution, including cost, quality, and access, identification and resolution of health disparities is a primary national agenda item. Resolution of disparities in amputation is an area of opportunity that warrants further consideration.

QUESTIONS/PURPOSES

The purposes of our review are to highlight current data on disparities in amputation in minorities and to consider future goals related to an elimination of this disparity.

METHODS

Studies on disparities in amputation were accessed using the following databases: PubMed, Cinahl, OVID/Medline, Embase, and Cochrane databases. In each database, a search of title/abstract was performed for the search terms "disparities and amputation," "race and amputation," and "diabetes and amputation." Each search was limited by human and English language. Where are we now? A disparity exists in both frequency and level of amputation in minorities both in the presence and absence of a diagnosis of diabetes. Where do we need to go? A need exists for future research involving a more deliberate examination of the use of preventive screening for patients at high risk for amputation across medical settings. How do we get there? Research in this area would benefit from funding, large-scale data collection, and physician exposure to education on high-risk patients and preventive screening opportunities.

24-Hour ambulatory blood pressure response to combination valsartan/hydrochlorothiazide and amlodipine/hydrochlorothiazide in stage 2 hypertension by ethnicity: the EVALUATE study

Several studies reported racial/ethnic differences in blood pressure (BP) response to antihypertensive monotherapy. In a 10-week study of stage 2 hypertension, 320/25 mg valsartan/hydrochlorothiazide (HCTZ) reduced ambulatory BP (ABP) significantly more effectively than 10/25 mg amlodipine/HCTZ. Results (post hoc analysis) are described in Caucasians (n=256), African Americans (n=79), and Hispanics (n=86). Compared with clinic-measured BP (no significant treatment-group differences in ethnic subgroups), least-squares mean reductions from baseline to week 10 in mean ambulatory systolic BP (MASBP) and mean ambulatory diastolic BP (MADBP) favored valsartan/HCTZ over amlodipine/HCTZ in Caucasians (-21.9/-12.7 mm Hg vs -17.6/-9.5 mm Hg; P=.0004/P<.0001). No treatment-group differences in MASBP/MADBP were observed in African Americans (-17.3/-10.6 vs -17.9/-9.5; P=.76/P=.40) or Hispanics (-17.9/-9.7 vs -14.2/-7.2; P=.20/P=.17). Based on ABP monitoring, valsartan/HCTZ is more effective than amlodipine/HCTZ in lowering ABP in Caucasians. In African Americans and Hispanics, both regimens are similarly effective.

Valsartan combination therapy in the management of hypertension - patient perspectives and clinical utility

The morbidity and mortality benefits of lowering blood pressure (BP) in hypertensive patients are well established, with most individuals requiring multiple agents to achieve BP control. Considering the important role of the renin-angiotensin-aldosterone system (RAAS) in the pathophysiology of hypertension, a key component of combination therapy should include a RAAS inhibitor. Angiotensin receptor blockers (ARBs) lower BP, reduce cardiovascular risk, provide organ protection, and are among the best tolerated class of antihypertensive therapy. In this article, we discuss two ARB combinations (valsartan/hydrochlorothiazide [HCTZ] and amlodipine/valsartan), both of which are indicated for the treatment of hypertension in patients not adequately controlled on monotherapy and as initial therapy in patients likely to need multiple drugs to achieve BP goals. Randomized, double-blind studies that have assessed the antihypertensive efficacy and safety of these combinations in the first-line treatment of hypertensive patients are reviewed. Both valsartan/HCTZ and amlodipine/valsartan effectively lower BP and are well tolerated in a broad range of patients with hypertension, including difficult-to-treat populations such as those with severe BP elevations, prediabetes and diabetes, patients with the cardiometabolic syndrome, and individuals who are obese, elderly, or black. Also discussed herein are patient-focused perspectives related to the use of valsartan/HCTZ and amlodipine/valsartan, and the rationale for use of single-pill combinations as one approach to enhance patient compliance with antihypertensive therapy.

Geographical distribution of surgical capabilities and disparities in the use of high-volume providers: the case of coronary artery bypass graft

BACKGROUND

Previous studies have documented substantial differences by patient race/ethnicity and insurance in the use of high-volume surgical providers. The extent to which regional availability of surgical capabilities explains such differences has not been examined.

OBJECTIVES

To examine the existence of racial/ethnic and payer differences in using high-volume hospitals and surgeons for coronary artery bypass graft (CABG) in the state of Florida and to study the role of regional availability of high-volume providers in explaining the differences.

RESEARCH DESIGN

We conducted descriptive analysis of the distribution of CABG providers and patient populations by race/ethnicity and insurance across the 19 Hospital Referral Regions (HRRs) in Florida. We estimated logistic regressions of using a high-volume provider to derive estimates of overall group differences. We further estimated models with HRR fixed effects to derive within-HRR differences. We derived implications by comparing findings based on the 2 sets of models.

RESULTS

Non-Hispanic black patients were 58% as likely (95% CI: 52%, 65%), Hispanic patients were 84% as likely (95% CI: 77%, 90%), to have received CABGs at a high-volume hospital, compared with non-Hispanic whites. Controlling for inter-HRR differences eliminated almost all racial/ethnic differences. Substantial differences in using high-volume providers existed between Medicaid/uninsured and privately insured patients and such differences persisted within HRRs.

CONCLUSIONS

Unequal distribution of CABG capabilities coupled with racial/ethnic concentration in residence across Florida HRRs accounted for almost all racial/ethnic differences in using high-volume hospitals. Factors other than availability of surgical resources were responsible for differences between Medicaid/uninsured and privately insured patients.

Adiposity, the metabolic syndrome, and breast cancer in African-American and white American women

Breast cancer, the second most common cause of cancer-related deaths in American women, varies substantially in incidence and mortality according to race and ethnicity in the United States. Although the overall incidence of breast cancer among African-American (AA) women is lower than in white American women, this cancer is more common in young premenopausal AA women, and AA breast cancer patients of all ages are more likely to have advanced disease at diagnosis, higher risk of recurrence, and poorer overall prognosis. Epidemiological studies indicate that these differences may be attributable in part to variation in obesity and body fat distribution. Additionally, AA women more frequently exhibit breast cancer with an aggressive and metastatic phenotype that may also be attributable to the endocrine and metabolic changes associated with upper body obesity. These changes include both elevated estrogen and androgen bioactivity, hyperinsulinemia, and perturbations of the adipokines. Type 2 diabetes and the metabolic syndrome, which are more common in AA women, have also been associated with breast cancer risk. Moreover, each of the individual components of the syndrome has been associated with increased breast cancer risk, including low levels of the adipocytokine, adiponectin. This review explores the specific roles of obesity, body fat distribution (particularly visceral and sc adipose tissue), type 2 diabetes, metabolic syndrome, and adipocytokines in explaining the differential patterns of breast cancer risk and prognosis between AA and white American women.

Cardiovascular health disparities: a systematic review of health care interventions

Racial and ethnic disparities in cardiovascular health care are well documented. Promising approaches to disparity reduction are increasingly described in literature published since 1995, but reports are fragmented by risk, condition, population, and setting. The authors conducted a systematic review of clinically oriented studies in communities of color that addressed hypertension, hyperlipidemia, physical inactivity, tobacco, and two major cardiovascular conditions, coronary artery disease and heart failure. Virtually no literature specifically addressed disparity reduction. The greatest focus has been African American populations, with relatively little work in Hispanic, Asian, and Native American populations. The authors found 62 interventions, 27 addressing hypertension, 9 lipids, 18 tobacco use, 8 physical inactivity, and 7 heart failure. Only 1 study specifically addressed postmyocardial infarction care. Data supporting the value of registries, multidisciplinary teams, and community outreach were found across several conditions. Interventions addressing care transitions, using telephonic outreach, and promoting medication access and adherence merit further exploration.

Race and ethnicity in trials of antihypertensive therapy to prevent cardiovascular outcomes: a systematic review

PURPOSE

We wanted to systematically review (1) the participation of racial and ethnic minorities in clinical trials of antihypertensive drug therapy and (2) racial differences in the efficacy of these therapies for the prevention of cardiovascular outcomes.

METHODS

MEDLINE, EMBASE, LILACS, African Index Medicus, and the Cochrane Library were searched from their inception to December 2005 for randomized controlled trials testing the efficacy of antihypertensive drug therapy in preventing myocardial infarction, stroke, revascularization, or cardiovascular death. MEDLINE was also searched from 2005 through 2006. The 2 authors independently assessed studies for inclusion and quality.

RESULTS

Twenty-eight studies met inclusion criteria. Eight trials reported results by racial subgroup. Trials with black and Hispanic participants (ALLHAT, INVEST, VALUE) found similar primary outcomes, but ALLHAT found a greater magnitude of benefit for blacks on diuretic therapy compared with nonblacks. One trial (PROGRESS) compared Asians with non-Asians, reporting that angiotensin-converting enzyme inhibitors (vs placebo) were equally effective for preventing stroke in both groups. In the LIFE trial, post hoc analyses showed different outcomes for blacks and nonblacks, raising questions about the usefulness of angiotensin-receptor blockers as first-line antihypertensive agents in blacks. In 3 studies conducted exclusively in Asians (JMIC-B, FEVER, NICS-EH), calcium channel blockers were effective in preventing cardiovascular outcomes. No trials described cardiovascular outcomes in Native Americans.

CONCLUSIONS

Five trials made interethnic group comparisons; 4 had similar primary outcomes for ethnic minorities and whites. Increased minority participation in future studies is needed to determine optimal prevention therapies, especially in outcome-driven trials comparing multidrug antihypertensive treatment regimens.

Factors influencing blood pressure response to trandolapril add-on therapy in patients taking verapamil SR (from the International Verapamil SR/Trandolapril [INVEST] Study)

Factors such as age and race/ethnicity might influence blood pressure (BP) response to drugs. Therapeutic response to the angiotensin-converting enzyme inhibitor trandolapril used as add-on therapy to stable calcium channel blocker therapy with verapamil sustained release 240 mg was addressed in a racially/ethnically diverse group of 1,832 hypertensive patients with coronary artery disease. Furthermore, the association with a polymorphism (1166A-->C) in the angiotensin II type 1 receptor gene (AGTR1) was tested. BP response was compared between groups using analysis of covariance after adjustment for covariates associated with BP response. Genotyping was performed using polymerase chain reaction and pyrosequencing. Trandolapril decreased mean unadjusted systolic and diastolic BPs by -9.1 +/- 17.3 (SD) and -4.1 +/- 10.1 mm Hg, respectively. The percentage of patients with BP under control (<140/90 mm Hg) increased from 6.7% to 41.3% (p <0.0001). Adjusted BP response was significantly associated with age and baseline systolic and diastolic BP (p <0.0001). Whereas the decrease in systolic BP was more pronounced in younger patients, the opposite was observed for diastolic BP decrease. Diastolic BP response was also significantly associated with race. Specifically, the adjusted diastolic BP decrease was significantly smaller in Hispanics and blacks than whites (p = 0.0032 and p = 0.0069, respectively). However, Hispanics achieved a decrease in systolic BP and an increase in BP control similar to the other ethnic groups. There was no genetic association between AGTR1 1166A-->C genotype and BP response. In conclusion, trandolapril add-on therapy was effective in increasing BP control, with age and baseline BP associated with both systolic and diastolic BP response. Race was associated with diastolic BP response, although the difference is likely not to be clinically significant and AGTR1 genotype was not associated with BP response.

Rural-urban Differences in Factors Associated with Poor Blood Pressure Control Among Outpatients

BACKGROUND

The purpose of this study was to determine which patient-related factors are most strongly associated with having uncontrolled hypertension among outpatients.

METHODS

A sample of 300 outpatients with diagnosed hypertension from three different settings was reviewed, focusing on demographics, comorbidity, adherence, and treatment factors. Regression analyses were conducted to determine which factors were associated with poor BP control (> 140 mmHg systolic or > 90 mmHg diastolic).

RESULTS

Those most strongly associated with blood pressure control were men (OR 2.04, 95% CI 1.17-3.55) living in a rural setting (OR 0.30, 95% CI 0.16-0.55). Age, race, total number of medicines, number of visits, and the number of comorbidities were not significantly associated with poor blood pressure control in this population.

CONCLUSIONS

Being urban and male are strongly associated with uncontrolled hypertension. Public health blood pressure control efforts in the Southeast region should be directed toward this population.

Race/ethnicity and fracture risk assessment: an issue that is more than skin deep

The study of race/ethnicity in relation to health outcomes and health disparities is of great importance in medicine. This is as true in the field of osteoporosis as it is in others, and it comes into sharp focus when the question of population-specific reference data for bone densitometry arises. Race/ethnicity can be viewed as both an ecosocial construct and as a biomedical concept. Whether or not, and how, to use race/ethnicity in fracture assessment potentially places these two paradigms in opposition. In this article, some of the issues that need to be considered to develop a rational approach to reference data selection and a globally acceptable measure of fracture risk are reviewed. Race/ethnicity is often a proxy for other disease-related risk factors. Understanding fundamental risk factors goes beyond the language of race/ethnicity.

Telmisartan/hydrochlorothiazide in the treatment of hypertension

Telmisartan blocks the detrimental actions of angiotensin II mediated via the angiotensin type 1 receptor. Unique features of telmisartan are high lipophilicity and a long terminal elimination half-life (~ 24 h). Telmisartan/hydrochlorothiazide is indicated for hypertensive patients unable to achieve target blood pressure with either monotherapy. Fixed-dose combination tablets containing telmisartan 40 or 80 mg and hydrochlorothiazide 12.5 mg are widely available; in addition, telmisartan/hydrochlorothiazide 80/25 mg is available in the USA. Telmisartan/hydrochlorothiazide is superior to losartan/hydrochlorothiazide and valsartan/hydrochlorothiazide in maintaining blood pressure control in the risky early morning hours at the end of the dosing interval. Furthermore, telmisartan/ hydrochlorothiazide provides superior 24-h mean blood pressure reduction and is better tolerated than amlodipine/hydrochlorothiazide in elderly patients with predominantly systolic hypertension. Telmisartan has the potential to confer additional reno- and cardioprotection to that due to blood pressure control. The cardioprotective activity of renin–angiotensin system blockade with telmisartan alone and in combination with ramipril is currently being evaluated in the ONgoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial (ONTARGET) and the Telmisartan Randomized AssessmeNt Study in aCE iNtolerant subjects with cardiovascular Disease (TRANSCEND). In total, 31,546 patients have been enrolled worldwide and are being followed for up to 5.5 years.