Samar A. Nasser

Epidemiology of Hypertension and Cardiovascular Disease in African Americans

Hypertension is a major cause of cardiovascularrenal morbidity and mortality and all‐cause mortality. It is a highly significant problem for African Americans; about 30% of all deaths in this population are attributable to hypertension. Compared with whites, hypertension in African Americans is more prevalent, occurs earlier in life, is more severe, and is more often associated with target organ injury such as left ventricular hypertrophy and other cardiovascular complications. Only 25% of all African Americans with hypertension and fewer than 50% of those receiving drug treatment attain a blood pressure <140/90 mm Hg. These control rates are some‐what less than in white Americans. Enhanced awareness and understanding of the epidemiologic patterns of hypertension, other cardiovascular risk factors, risk‐factor control rates, and factors influencing these control rates should lead to better approaches to riskfactor control. This most likely would result in a reduction of cardiovascular disease complications.

Determinants of Blood Pressure Response to Quinapril in Black and White Hypertensive Patients. The Quinapril Titration Interval Management Evaluation Trial

Race has been considered an important factor in determining blood pressure response to treatment and selection of antihypertensive drug therapy. Data collected during a clinical trial that evaluated rapidity of medication up-titration with blood pressure response to monotherapy with the angiotensin-converting enzyme (ACE) inhibitor quinapril were used to characterize response in 533 black and 2046 white participants. Our objectives were to examine the influence of race and other factors on blood pressure response and to assess the degree to which nonrace factors account for apparent racial differences in response. Average systolic and diastolic blood pressure responses (baseline minus follow-up) to treatment were assessed with treatment groups combined. Crude systolic and diastolic blood pressure responses averaged 4.7 and 2.4 mm Hg less, respectively, in black compared with white participants; however, the response distributions largely overlapped. In multivariate linear regression models adjusted for study design variables and measured participant characteristics, the racial difference in systolic response was reduced by 51% to 2.3 mm Hg, and diastolic response by 21% to 1.9 mm Hg. In these models, participant characteristics, including age, gender, body size, and pretreatment blood pressure severity, significantly predicted either attenuated or enhanced blood pressure response to treatment. Our findings demonstrate that a large source of variability of blood pressure response to treatment is within, not between, racial groups, and that factors that vary at the level of the individual contribute to apparent racial differences in response to treatment.

Prevention of hypertension and its complications: Theoretical basis and guidelines for treatment

Hypertension is a nutritional-hygienic disease. Long-term caloric intake in excess of energy expenditures, chronic supraphysiological intake of dietary sodium, excessive alcohol consumption, and psychosocial stressors all contribute to the development of hypertension throughout the world. Elevated BP, particularly systolic BP, has been linked to multiple adverse clinical outcomes including stroke, heart failure, myocardial infarction, renal insufficiency/failure, peripheral vascular disease, retinopathy, dementia, and premature mortality. These undesirable clinical outcomes are typically, although not invariably, preceded by pressure-related target-organ injury such as left ventricular hypertrophy, renal insufficiency and proteinuria. The relation of BP and CKD and, in turn, the prevention of CKD or forestalling its progression by hypertension treatment, will be the focus of this manuscript. In hypertensive persons with reduced kidney function and/or proteinuria, lowering BP with multidrug therapy that is inclusive of pharmacologic modulators of the renin-angiotensin-aldosterone-kinin system is an effective strategy to forestall the progressive loss of kidney function. The totality of data support low therapeutic BP targets for persons with proteinuria >1 g/d. Nevertheless, in persons with CKD, even those with proteinuria below the dipstick positive level (approximately 300 mg/d or urine protein to creatinine ratio of 0.22), aggressive BP control also may be warranted because of the high risk of nonrenal cardiovascular disease. Multiple antihypertensive drugs will be required in the vast majority of patients with diabetes and/or reduced kidney function to attain BP goal. Renin-angiotensin system (RAS) modulator therapy is indicated among persons with diabetes mellitus and CKD. Available data support the use of angiotensin receptor blockers in persons with type 2 diabetes and overt nephropathy for preservation of kidney function. Among persons with type I diabetes with or without overt nephropathy, type 2 diabetes without overt nephropathy and in nondiabetic CKD, the available clinical data support the use of angiotensin-converting enzyme inhibitors as the RAS modulator of choice. Low therapeutic target BP levels <130/80 mmHg in persons with type 2 diabetes mellitus also appear warranted based on available data mostly for reducing the risk of nonrenal cardiovascular disease and overall mortality.

Hypertension in special populations

This article discusses various aspects of hypertension in selected special populations. The groups discussed herein are children, pregnant women, African Americans, persons with kidney insufficiency, kidney transplant survivors, and persons with diabetes mellitus. These groups present unique epidemiological, diagnostic and therapeutic challenges for the practitioner. The detection of reduced kidney function merits special attention since it attenuates the blood pressure response to antihypertensive therapy, affects therapeutic decision-making, is both a cause and consequence of poorly controlled hypertension, often lurks undetected, and is excessively prevalent in some special populations.

Community‐Based Approaches to Prevention and Management of Hypertension and Cardiovascular Disease

J Clin Hypertens (Greenwich). 2012; 14:336–343. ©2012 Wiley Periodicals, Inc.

Therapy of Hypertension in African Americans

Hypertension in African Americans is a major clinical and public health problem because of the high prevalence and premature onset of elevated blood pressure (BP) as well as the high burden of co-morbid factors that lead to pharmacological treatment resistance (obesity, diabetes mellitus, depressed glomerular filtration rate, and albuminuria). BP control rates are lower in African Americans, especially men, than in other major race/ethnicity-sex groups; overall control rates are 29.9% for non-Hispanic Black men. Optimal antihypertensive treatment requires a comprehensive approach that encompasses multifactorial lifestyle modifications (weight loss, salt and alcohol restriction, and increased physical activity) plus drug therapy. The most important initial step in the evaluation of patients with elevated BP is to appropriately risk stratify them to allow determination of whether they are truly hypertensive and also to determine their goal BP levels. The overwhelming majority of African American hypertensive patients will require combination antihypertensive drug therapy to maintain BP consistently below target levels. The emphasis is now appropriately on utilizing the most effective drug combinations for the control of BP and protection of target-organs in this high-risk population. When BP is > 15/10 mmHg above goal levels, combination drug therapy is recommended. The preferred combination is a calcium antagonist/angiotensin-converting enzyme inhibitor or, alternatively, in edematous and/or volume overload states, a thiazide diuretic/angiotensin-converting inhibitor.

Benefits of once-daily therapies in the treatment of hypertension

In patients with hypertension, 24-hour blood pressure control is the major therapeutic goal. The number of daily doses is one characteristic of an antihypertensive agent that may affect the adequacy of 24-hour control. One measure of therapeutic coverage is the 24-hour trough-to-peak ratio, which determines the suitability of an agent for once-daily administration. The closer an agent is to a 100% trough-to-peak ratio, the more uniform the 24-hour coverage and therefore blood pressure control. High trough-to-peak ratio, long-acting antihypertensive medications lower blood pressure more gradually, which reduces the likelihood of adverse events attributable to abrupt drug action that occurs with shorter-acting agents. In hypertension, the natural diurnal variation of blood pressure may be altered, including elevated nighttime pressures. An optimal once-daily hypertension therapy would not only lower blood pressure but also normalize any blunted circadian variations in blood pressure. The benefits of once-daily agents with sustained therapeutic coverage may also be explained, in part, by increased patient adherence to simpler regimens as well as lower loss of blood pressure control during virtually inevitable intermittent noncompliance. Studies have demonstrated that once-daily antihypertensive agents have the highest adherence compared with twice-daily or multiple daily doses, including greater adherence to the prescribed timing of doses.

Cardiorenal Metabolic Syndrome and Cardiometabolic Risks in Minority Populations

Cardiovascular disease (CVD), including heart disease and stroke, is the leading cause of death in the USA, regardless of self-determined race/ethnicity, and largely driven by cardiometabolic risk (CMR) and cardiorenal metabolic syndrome (CRS). The primary drivers of increased CMR include obesity, hypertension, insulin resistance, hyperglycemia, dyslipidemia, chronic kidney disease as well as associated adverse behaviors of physical inactivity, smoking, and unhealthy eating habits. Given the importance of CRS for public health, multiple stakeholders, including the National Minority Quality Forum (the Forum), the American Association of Clinical Endocrinologists (AACE), the American College of Cardiology (ACC), and the Association of Black Cardiologists (ABC), have developed this review to inform clinicians and other health professionals of the unique aspects of CMR in racial/ethnic minorities and of potential means to improve CMR factor control, to reduce CRS and CVD in diverse populations, and to provide more effective, coordinated care. This paper highlights CRS and CMR as sources of significant morbidity and mortality (particularly in racial/ethnic minorities), associated health-care costs, and an evolving index tool for cardiometabolic disease to determine geographical and environmental factors. Finally, this work provides a few examples of interventions potentially successful at reducing disparities in cardiometabolic health.

Hypertension in Special Populations: Chronic Kidney Disease, Organ Transplant Recipients, Pregnancy, Autonomic Dysfunction, Racial and Ethnic Populations

The benefits of appropriate blood pressure (BP) control include reductions in proteinuria and possibly a slowing of the progressive loss of kidney function. Overall, medication therapy to lower BP during pregnancy should be used mainly for maternal safety because of the lack of data to support an improvement in fetal outcome. The major goal of hypertension treatment in those with baroreceptor dysfunction is to avoid the precipitous, severe BP elevations that characteristically occur during emotional stimulation. The treatment of hypertension in African Americans optimally consists of comprehensive lifestyle modifications along with pharmacologic treatments, most often with combination, not single-drug, therapy.

Reply: Directly Observed Therapy: A Possible Tool to Tackle Medication Nonadherence in the CVD Epidemic

We appreciate Drs. Mezue and Rangaswami’s interest in our State-of-the-Art Review paper [(1)][1] and would like to respond by making the following 4 points. First, we agree there is good evidence of directly observed therapy (DOT) specifically with infectious diseases (e.g., tuberculosis [TB] and