Daniel W. Jones

Recommendations for blood pressure measurement in humans: An AHA scientific statement from the council on high blood pressure research professional and public education subcommittee

VOL. 7 NO. 2 FEBRUARY 2005 102 Ten years have passed since the last version of the American Heart Association (AHA) blood pressure (BP) measurement recommendations,1 during which time there have been major changes in the ways in which BP is measured in clinical practice and research; hence this document represents a major revision of previous versions.2 BP determination continues to be one of the most important measurements in clinical medicine, and still one of the most inaccurately performed. The gold standard for clinical BP measurement has always been readings taken by a trained health care provider using a mercury sphygmomanometer and the Korotkoff sound technique. There is increasing evidence, however, that this procedure may lead to the misclassification of large numbers of individuals as hypertensive, and fail to diagnose other individuals whose BP may be normal in the clinic setting but elevated at other times. There are three reasons for this: 1) inaccuracies in the methods, some of which are avoidable; 2) the inherent variability of BP; and 3) the tendency for BP to increase in the presence of a physician (the so-called “white coat effect”). Numerous surveys have shown that physicians and other health care providers rarely follow established guidelines for BP measurement, but when they do, the readings they get correlate more closely with more objective measures of BP than the usual clinic readings. It is generally agreed that conventional clinic readings, when made correctly, are a surrogate marker for a patient’s true BP, which is conceived as the average level over prolonged periods of time, and which is thought to be the most important component of BP in determining its adverse effects. Usual clinic readings give a poor estimate of this, not only because of poor technique, but also because they typically consist only of one or two individual measurements, and the beat-to-beat BP variability is such that a small number of readings may only give a crude estimate of the average level. The recognition of these limitations of traditional clinic readings has led to two parallel developments: first, increasing use of measurements out of the clinic, Recommendations for Blood Pressure Measurement in Humans: An AHA Scientific Statement from the Council on High Blood Pressure Research Professional and Public Education Subcommittee

Antihypertensive effect of α- and β-adrenergic blockade in obese and lean hypertensive subjects

The purpose of this study was to determine the contribution of the adrenergic system in mediating hypertension in obese and lean patients. Thirteen obese, hypertensive patients with a body mass index (BMI) ≥28 kg/m2 (obese) and nine lean patients with a BMI ≤25 kg/m2 (lean) were recruited. After a 1-week washout period, participants underwent daytime ambulatory blood pressure monitoring (ABPM). Participants were then treated with the α-adrenergic antagonist doxazosin, titrating to 4 mg QHS in 1 week. In the next week, the β-adrenergic antagonist atenolol was added at an initial dose of 25 mg/day and titrated to 50 mg/day within 1 week. One month after the addition of atenolol, all patients underwent a second ABPM session. There were no differences between the obese and lean subjects in baseline systolic (SBP), diastolic (DBP), or mean arterial pressures (MAP) measured by office recording or ABPM. However, obese subjects had higher heart rates than lean subjects (87.5 ± 2.4 v 76.8 ± 4.9 beats/min). After 1 month of treatment with the adrenergic blockers, obese patients had a significantly lower SBP (130.0 ± 2.5 v 138.9 ± 2.1 mm Hg, P = .02) and MAP (99.6 ± 2.3 v 107.0 ± 1.5 mm Hg, P = .02) than lean patients. Obese patients also tended to have a lower DBP than lean patients (84.3 ± 2.5 v 90.9 ± 1.6 mm Hg, P = .057), but there was no significant difference in heart rate after 1 month of adrenergic blockade. These results indicate that blood pressure is more sensitive to adrenergic blockade in obese than in lean hypertensive patients and suggest that increased sympathetic activity may be an important factor in the maintenance of hypertension in obesity.

Cognitive Impairment Associated with Atorvastatin and Simvastatin

Clinical guidelines for cholesterol testing and management have been updated recently. With the evolving recognition of benefits and intensified recommendations for cholesterol management, many more patients will require cholesterol‐lowering drugs. All the statins share similar adverse‐effect profiles, with a low overall frequency of undesirable effects. Emerging data associate statins with a decreased risk of Alzheimers disease; however, we report two women who experienced significant cognitive impairment temporally related to statin therapy. One woman took atorvastatin, and the other first took atorvastatin, then was rechallenged with simvastatin. Clinicians should be aware of cognitive impairment and dementia as potential adverse effects associated with statin therapy.

Body weight and blood pressure Effects of weight reduction on hypertension

A substudy of the Hypertension Optimal Treatment study, conducted in the Jackson Mississippi Center, set out to determine the link between obesity and hypertension and to determine the effects of weight loss in hypertensive individuals. An analysis of the relationship between body mass index and diastolic blood pressure for another study showed that increasing body mass indices were associated with increases in blood pressure. This indicates that not only is there a strong relationship between obesity and hypertension, but that there is also a close association between the continuous variables of body mass index and blood pressure. The purpose of the present study was to determine the effectiveness of a weight loss regimen in reducing the amount of medication required to achieve the target blood pressure in 228 patients at the Jackson center. Subjects were randomized to a dietary intervention group or to a control group. Preliminary 3 month observational data showed that subjects who lost the appropriate amount of weight were three times more likely to achieve their target blood pressure at 3 months. These observations suggest that weight reduction regimens can reduce elevated blood pressure and can probably promote further blood pressure reductions when combined with drug therapy in the treatment of hypertension.

Racial and Ethnic Differences in Blood Pressure Biology and Sociology

In the last few years, much attention has been given to racial and ethnic differences in health measures. Not surprisingly, much of the work in this area is being done in the United States. Not only does our unique racial and ethnic diversity offer opportunities for study, but the social and political issues related to this diversity have driven a need to understand the disparities in health related to these differences. Article p 2780 These racial and ethnic differences in health measures are seen clearly in cardiovascular disease risk factors and outcomes for Americans of African descent, or African Americans (AAs), compared with those of European descent, or European Americans (EAs). Compared with EAs, AAs have higher mortality rates for most cardiovascular diseases, including coronary heart disease and stroke. These differences are magnified at younger ages.1 Prevalence rates for key risk factors differ for AAs, with higher rates for hypertension, obesity, and diabetes mellitus, and lower rates for dyslipidemia. Additionally, the cardiovascular consequences imposed by various risk factors differ by race. Compared with hypertensive EA men and women and AA men, AA women with hypertension have a substantially greater relative risk for heart disease. Conversely, AA women have a substantially lower relative risk for diabetes mellitus than EA women.2 The disparities in cardiovascular outcome are large and significant, and the disparities in outcome have worsened in the last 2 decades.3 Appropriately, much attention is being given to understanding these differences. For a number of years, this important area of study was hampered by a lack of interest and a lack of funding. Now that a commitment is being made in this area, other challenges of understanding the causes of these differences are becoming clearer. The science is complex.3 The challenges to understanding the science of racial …

Rising Levels of Cardiovascular Mortality in Mississippi, 1979-1995

BACKGROUND Cardiovascular disease rates are improving in the United States, but not for certain subgroups, especially some African Americans. The objective of the study is to assess current levels and trends in cardiovascular disease mortality in Mississippi. METHODS Mortality statistics from the U.S. vital statistics system for the period 1979-95 were used. Comparison of age-adjusted mortality rates in Mississippi with the other states for the year 1995 and with the nation as a whole over the period of 1979-95 was performed. RESULTS Mississippians had the highest age-adjusted cardiovascular disease morality rates in the nation in 1995. Overall, the cardiovascular rates in Mississippi were 37% higher than for the U.S. African American men and women from Mississippi had especially high cardiovascular mortality rates, approximately 50% and 70% higher than their white counterparts, respectively. The higher burden of cardiovascular disease in African Americans from Mississippi was especially marked in the younger age groups. Since about 1984-85, cardiovascular mortality rates in Mississippi have been increasing for African Americans, whereas nationally they have been decreasing. In contrast, cardiovascular mortality rates for whites in Mississippi have been declining, but at a much slower rate than seen nationally. The wide divergence in trends for African American and white men and women over that period in Mississippi has lead to an estimated 19,400 excess cardiovascular deaths. Virtually identical trends were found for heart disease. CONCLUSIONS Cardiovascular diseases are a major public health problem in Mississippi that is especially severe in African American residents, and the problem is growing worse each year. It is important to identify the determinants of and solutions for this enormous public health problem in Mississippi.

SPRINT What Remains Unanswered and Where Do We Go From Here

The Systolic Blood Pressure Intervention Trial (SPRINT) main results were recently published and presented at the American Heart Association Scientific Sessions.1 These data provide insight into the important question of the most appropriate treatment goal for systolic blood pressure (BP). The results of this study will have a large and lasting impact on the management of patients with hypertension. The study answers a critical question, but important questions remain. The large over-riding question remaining from the SPRINT trial is this: How generalizable are the results? The J-curve relationship between systolic BP and risk is present in every individual and every group.2 What has been uncertain is where the inflection point on the J curve is and how the J curve relationship is impacted by chronic hypertension, age, diabetes mellitus, chronic kidney disease, and atherosclerotic disease leading to stroke and heart disease. The SPRINT has answered some of these questions, but some remain unanswered. Perhaps, the most important question coming from the SPRINT involves a group of patients not included in the trial: patients with diabetes mellitus. A few years earlier, the Action to Control Cardiovascular Risk in Diabetes (ACCORD) study3 was done to determine the appropriate goal systolic BP for patients with diabetes mellitus. ACCORD did not demonstrate a benefit for a systolic BP goal of 120 versus 140 mm Hg. On the basis of those results, most current guidelines call for lowering BP to the range of 135 to 140 mm Hg in diabetic patients.4,5 If the interpretation of the ACCORD results is correct, is the reason for lower BP goals leading to better results in SPRINT …

Managing hypertension in the southeastern United States: applying the guidelines from the Sixth Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC VI).

The southeastern United States has the highest occurrence of heart disease and stroke and among the highest rates of congestive heart failure and renal failure in the country. The Consortium for Southeastern Hypertension Control (COSEHC) is cooperating with other organizations in implementing initiatives to reduce morbidity and mortality from hypertension-related conditions in the southeastern United States. This article outlines for clinicians special consideration for implementation of the Sixth Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC VI) in the southeastern United States. Clinicians are encouraged to adapt the recommendations of JNC VI to their own patient groups, paying attention to these specific areas: (1) Ensure screening for hypertension in your practice and community. (2) Evaluate all patients for accompanying risk factors and target organ damage. (3) Promote lifestyle management for individual patients and populations for prevention and treatment of hypertension. (4) Set a goal blood pressure for each patient, and monitor progress toward that goal. (5) Recognize that many patients will be candidates for blood pressure goals of <130/85 mm Hg. (6) Pay attention to compelling and special indications such as diabetes, congestive heart failure, and renal dysfunction. (7) Consider combination therapy. (8) Maximize staff contributions to enhance patient adherence. (9) Encourage patient, family, and community activities to promote healthy lifestyles and blood pressure control.

Weight change among self-reported dieters and non-dieters in white and African American men and women

Few studies have examined the association between dieting and weight change in general population and results have been inconsistent. To the best of our knowledge, no such study has been done in middle-aged African Americans. We examined 10,554 white and African American men and women who were participants in the Atherosclerosis Risk in Communities (ARIC) Study and attended examinations between 1986 and 1994. We found that the prevalence of dieting in white women, white men, African American women, and African American men was 6.5, 2.3, 3.5, and 0.9%, respectively. After controlling for the covariates, the difference in the mean annual weight gain between dieters and non-dieters was 0.61, 0.46, and 0.59 kg/year among white women, white men, and African American women, respectively. In conclusion, in this cohort of white men and women and African American women aged 45–64 years, self-reported dieting was associated with a larger mean annual weight gain than non-dieting over a period of 6 years.

What Is the Role of Obesity in Hypertension and Target Organ Injury in African Americans

Hypertension is the most common reversible risk factor for cardiovascular disease. It is especially common in African Americans. One of the factors that may contribute to the high rates of hypertension and target organ injury in African Americans is obesity. Hypertension and obesity are common among African Americans. Obesity is particularly common in African American women. About 75% of African American women are obese. Regulation of both body weight and blood pressure are complex, involving an interaction of genetic and environmental factors. Most research thus far has focused on blood pressure control systems studied in other forms of hypertension, including the sympathetic nervous system, the renin angiotensin system, and metabolic factors-primarily insulin resistance. Proposed mechanisms that are unique to obesity-associated hypertension include: 1) intrarenal physical forces associated with obesity-induced changes in the renal medulla; 2) genetic/metabolic factors; and 3) metabolic effects of abdominal visceral fat. The Jackson Heart Study provides a unique opportunity to address unresolved questions in the relationship of body weight, blood pressure, and cardiovascular disease.