Showing papers in "Journal of Clinical Hypertension in 2007"

Mechanisms of Cardiac Fibrosis in Hypertension

Abstract: Changes in the composition of cardiac tissue develop in hypertensive patients with left ventricular hypertrophy (ie, hypertensive heart disease) and lead to structural remodeling of the myocardium. One of these changes is related to the disruption of the equilibrium between the synthesis and degradation of collagen types I and III molecules, which results in an excessive accumulation of collagen types I and III fibers within the myocardium. Myocardial fibrosis is the consequence of a number of pathologic processes mediated by mechanical, neurohormonal, and cytokine routes. The clinical relevance of fibrosis is that it may contribute to heart failure and other cardiac complications in patients with hypertensive heart disease. This brief review focuses on the mechanisms of hypertensive myocardial fibrosis.

Prevalence and Predictors of Poor Antihypertensive Medication Adherence in an Urban Health Clinic Setting

Abstract: Poor medication adherence may contribute to low hypertension control rates. In 2005, 295 hypertensive patients who reported taking antihypertensive medication were administered a telephone questionnaire including an 8-item scale assessing medication adherence. Overall, 35.6%, 36.0%, and 28.4% of patients were determined to have good, medium, and poor medication adherence, respectively. After multivariable adjustment, adults younger than 50 years and 51 to 60 years were 1.39 (95% confidence interval [CI], 0.56-3.42) and 1.53 (95% CI, 0.64-3.66), respectively, times more likely to be less adherent when compared with their counterparts who were older than 60 years. Black adults and men were 4.30 (95% CI, 1.06-17.5) and 2.45 (95% CI, 1.04-5.78) times more likely to be less adherent, respectively. Additionally, caring for dependents, an initial diagnosis of hypertension within 10 years, being uncomfortable about asking the doctor questions, and wanting to spend more time with the doctor if possible were associated with poor medication adherence. The current study identified a set of risk factors for poor antihypertensive medication adherence in the urban setting.

Aortic Dissection

Abstract: Aortic root enlargement is generally asymptomatic, with few clinical clues, but may be observed as an incidental finding on a chest x-ray, echocardiogram, or contrast-enhanced computerized tomogram of the chest. Aortic dissection is one of the most feared complications of hypertension. A history of hypertension is commonly present, but the systolic blood pressure in type A dissection (proximal to the left subclavian artery) has been found to be less than 150 mm Hg in 64% of patients. However, 71% of type B dissections (distal to the left subclavian artery) present with a systolic blood pressure 150 mm Hg or higher (International Registry of Acute Aortic Dissection). Most frequently, onset of symptoms is in the daytime, especially between 6 a.m. and noon. Severe sharp chest pain that is abrupt in onset is the most likely presentation. Migrating pain is uncommon. Although a pulse deficit with decreased or absent carotid, brachial, or femoral pulses occurs in only 30% of patients, three or more deficits predict an in-house mortality of about 60%. A chest x-ray finding of a widened mediastinum is present in 62.6% of type A and 56% of type B dissections. Contrast-enhanced computerized tomography or transesophageal echocardiography is the most commonly performed procedure for diagnosis. In-house mortality has been found to be 32.5% in type A dissections and 13% in type B dissections.

Hypertensive pregnancy disorders : Current concepts

Abstract: Hypertensive pregnancy disorders complicate 10% of all pregnancies and cover a spectrum of conditions, namely preeclampsia, eclampsia, and chronic and gestational hypertension. Preeclampsia is a pregnancy-specific disorder clinically characterized by hypertension and proteinuria that occurs after 20 weeks of gestation. It remains a leading cause of both fetal and maternal morbidity and mortality worldwide. Traditionally, hypertensive pregnancy disorders were considered not to have any long-term impact on mothers' cardiovascular health; however, recent studies consistently have supported the role of hypertension in pregnancy as a risk factor for cardiovascular disease later in life. Therefore, improved screening, and preventive and treatment strategies may not only optimize management of hypertensive pregnancy disorders, but may have a long-term impact on women's cardiovascular events and outcomes years after the affected pregnancies. This article will provide a brief review of hypertensive pregnancy disorders and important recent discoveries regarding their pathogeneses, while focusing on current diagnostic and treatment strategies.

Antihypertensive Efficacy of the Oral Direct Renin Inhibitor Aliskiren as Add-On Therapy in Patients Not Responding to Amlodipine Monotherapy

Abstract: This study investigated the addition of the direct renin inhibitor aliskiren to amlodipine in patients with mild to moderate hypertension that was inadequately controlled with amlodipine alone. Following once-daily treatment with amlodipine 5 mg for 4 weeks, patients whose hypertension responded inadequately to therapy (mean sitting diastolic blood pressure [DBP] 90–109 mm Hg) (n=545) were randomized to 6 weeks of double-blind treatment with amlodipine 5 mg plus aliskiren 150 mg, amlodipine 5 mg, or amlodipine 10 mg. At the study's end, mean systolic blood pressure and DBP reductions with the combination of aliskiren 150 mg and amlodipine 5 mg (11.0/8.5 mm Hg) were significantly greater (P<.0001) than with amlodipine 5 mg (5.0/4.8 mm Hg)—the comparator group—but similar to amlodipine 10 mg (9.6/8.0 mm Hg). All treatments were well tolerated. Edema occurred more frequently with amlodipine 10 mg (11.2%) than with combination therapy (2.1%) or amlodipine 5 mg (3.4%). In conclusion, aliskiren 150 mg plus amlodipine 5 mg shows similar but not better blood pressure-lowering efficacy when compared with amlodipine 10 mg in patients not completely responsive to amlodipine 5 mg; less edema was noted with combination therapy.

Ethnic/racial variations in blood pressure awareness, treatment, and control.

Abstract: Understanding the impact of patient factors on blood pressure (BP) management is an important step to developing interventions to improve cardiovascular health. The National Health and Nutrition Examination Survey (NHANES) 1999-2002 was used to identify predictors of hypertension awareness, treatment, and control. An estimated 63.3 million (31.0%) US adults currently have BP exceeding 140/90 mm Hg, and prevalence is higher for blacks than for other racial/ethnic subgroups. Among antihypertensive medication-treated patients, 51.3% are controlled. Treated blacks and Mexican Americans have the lowest rates of BP control. Mexican Americans are 0.62 times as likely to be aware and 0.61 times as likely to be treated as white persons with hypertension. Compared with whites, treated Mexican Americans are 0.71 times as likely and treated blacks 0.59 times as likely to achieve BP control. Hypertension treatment and BP control in the United States remain suboptimal, and significant racial/ethnic disparities persist. Effective interventions targeting Mexican Americans and blacks as well as whites are essential to improving hypertension management.

Efficacy and Safety of Darusentan in Patients With Resistant Hypertension: Results From a Randomized, Double-Blind, Placebo-Controlled Dose-Ranging Study

Abstract: In this phase 2, randomized, double-blind, placebo-controlled forced dose-titration study, 115 patients with resistant hypertension, receiving background therapy with >/=3 antihypertensive medications including a diuretic at full doses, were randomized 2:1 to increasing doses of darusentan (10, 50, 100, 150, and 300 mg), a selective endothelin receptor antagonist, or matching placebo once daily for 10 weeks. Darusentan treatment decreased mean systolic and diastolic blood pressure levels in a dose-dependent fashion compared with placebo; the largest reductions were observed at week 10 (300-mg dose) (systolic, -11.5+/-3.1 mm Hg [P=.015;] diastolic, -6.3+/-2.0 mm Hg [P=.002]). Darusentan (300 mg) also decreased mean 24-hour, daytime, and nighttime ambulatory blood pressures from baseline to week 10. Darusentan was generally well tolerated; mild to moderate edema and headache were the most common adverse events. This study demonstrates a clinical benefit from a new class of antihypertensive agent in patients classified as resistant by the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure guidelines.

Centrally acting antihypertensive agents: an update.

Abstract: Centrally acting agents stimulate alpha(2) receptors and/or imadozoline receptors on adrenergic neurons situated within the rostral ventrolateral medulla and, in so doing, sympathetic outflow is reduced. Centrally acting agents also stimulate peripheral alpha(2) receptors, which, for the most part, is of marginal clinical significance. Central a agonists have had a lengthy history of use, starting with alpha-methyldopa, which has had a dramatic decline in use, in part, because of bothersome side effects. Patients who require multidrug therapy with otherwise resistant hypertension, such as diabetic and/or renal failure patients, are typically responsive to these drugs, as are patients with sympathetically driven forms of hypertension. Perioperative forms of hypertension respond well to clonidine, a circumstance where the additional anesthesia- and analgesia-sparing effects of this drug may offer additional clinical benefits. Clonidine can be used adjunctively with other more traditional therapies in heart failure, particularly when hypertension is present. Sustained-release moxonidine, however, is associated with early mortality and morbidity when used in patients with heart failure. Escalating doses of drugs in this class often give rise to salt and water retention, in which case diuretic therapy becomes a valuable adjunctive therapy.

Hypertension management: results of a new national survey for the hypertension education foundation: Harris interactive.

Abstract: A new national online survey by Harris Interactive of 1245 hypertensive individuals indicates that >90% were aware that elevated blood pressure (BP) is a major risk factor for cardiovascular disease The majority discovered that they had elevated BP levels as a result of a routine examination More than two thirds of persons identified 120/80 mm Hg as an optimal BP level; only 60% stated that the Internet was their primary source of information about high BP More than 60% of respondents had a body mass index >30 kg/m(2), and >50% had other cardiovascular risk factors More than 50% were involved in some lifestyle change to control BP, and >90% were taking medication More than 60% reported that BP was controlled ( 90% of hypertensive patients are aware of the risks of elevated BP and that a high percentage of hypertensive patients are being treated with medication Control rates as reported by respondents were >60% based on last BP recorded; however, between 31% and 40% of patients (based on differences in ethnic groups) were continued on the same therapy despite elevated BP levels The survey suggests a high degree of risk awareness and treatment, and what appears to be an increase in control rates among hypertensive patients

Amlodipine and valsartan combined and as monotherapy in stage 2, elderly, and black hypertensive patients: subgroup analyses of 2 randomized, placebo-controlled studies.

Abstract: Patients with difficult to control hypertension typically require 2 or more agents to achieve goal blood pressure (BP) levels. Fixed-dose combination therapies with lower doses generally are well tolerated and more effective than higher-dose monotherapy. The authors performed prespecified and post hoc subgroup analyses of 2 double-blind, randomized, placebo-controlled trials that assessed the efficacy and safety of amlodipine and valsartan, alone and in combination, in patients with mild to moderate hypertension. Patients were randomized to amlodipine (study 1: 2.5 or 5 mg/d; study 2: 10 mg/d), valsartan (study 1: 40, 80, 160, or 320 mg/d; study 2: 160 or 320 mg/d), combination therapy across the same dose ranges, or placebo. Analyses were performed on changes from baseline in mean sitting systolic and diastolic BP and the occurrence of adverse events in specific subgroups of patients (ie, those with stage 2 hypertension [post hoc], the elderly [65 years or older], and blacks [both prespecified]). Amlodipine + valsartan combination therapy was associated with greater BP-lowering effects in the subgroups compared with each respective monotherapy and placebo. These findings were consistent with the primary efficacy analysis results from the overall study populations. Combination regimens were generally well tolerated by all patient subgroups.

Effect of Combined Treatment With α‐Lipoic Acid and Acetyl‐L‐Carnitine on Vascular Function and Blood Pressure in Patients With Coronary Artery Disease

Abstract: Mitochondria produce reactive oxygen species that may contribute to vascular dysfunction. alpha-Lipoic acid and acetyl-L-carnitine reduce oxidative stress and improve mitochondrial function. In a double-blind crossover study, the authors examined the effects of combined alpha-lipoic acid/acetyl-L-carnitine treatment and placebo (8 weeks per treatment) on vasodilator function and blood pressure in 36 subjects with coronary artery disease. Active treatment increased brachial artery diameter by 2.3% (P=.008), consistent with reduced arterial tone. Active treatment tended to decrease systolic blood pressure for the whole group (P=.07) and had a significant effect in the subgroup with blood pressure above the median (151+/-20 to 142+/-18 mm Hg; P=.03) and in the subgroup with the metabolic syndrome (139+/-21 to 130+/-18 mm Hg; P=.03). Thus, mitochondrial dysfunction may contribute to the regulation of blood pressure and vascular tone. Further studies are needed to confirm these findings and determine the clinical utility of alpha-lipoic acid/acetyl-L-carnitine as antihypertensive therapy.

Comparison of Increasing Doses of Olmesartan Medoxomil, Losartan Potassium, and Valsartan in Patients With Essential Hypertension

Abstract: This 12-week, randomized, double-blind, forced-titration study compared the efficacy of 3 angiotensin receptor blockers. Patients received olmesartan medoxomil 20 mg, losartan potassium 50 mg, valsartan 80 mg, or placebo once daily. At week 4, doses were titrated to 40, 100, and 160 mg once daily for olmesartan, losartan, and valsartan, respectively. At week 8, losartan was increased to 50 mg twice daily and valsartan increased to 320 mg once daily (olmesartan remained at 40 mg once daily). The primary end point was mean change from baseline in seated diastolic blood pressure (SeDBP) at week 8. All 3 medications significantly reduced mean SeDBP from baseline compared with placebo at weeks 4, 8, and 12 (P<.001). At week 8, olmesartan reduced mean SeDBP more than losartan (P<.001); more patients in the olmesartan medoxomil group achieved a blood pressure goal of <140/90 mm Hg (P<.001). Olmesartan did not reduce mean SeDBP significantly compared with valsartan, although more patients attained blood pressure goal with olmesartan (P=.031). At week 12, all agents lowered blood pressure equivalently.

Explicit and implicit evaluation of physician adherence to hypertension guidelines

Abstract: This study evaluated physician adherence to the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) hypertension guidelines in 6 community-based clinics. Explicit review of retrospective medical record data for patients with uncontrolled hypertension measured guideline adherence using 22 criteria. Mean overall guideline adherence was 53.5% and did not improve significantly over time. Random-effects models demonstrated significant associations between guideline adherence and various demographic and medical predictors, including age, minority status, comorbid conditions, and number of medications. A subsequent implicit review evaluated the degree to which nonadherence was justifiable and identified factors that might have affected adherence. Nonadherence was rated as justifiable for only 6.6% of the failed explicit criteria. In general, adherence to the JNC 7 guidelines was modest even when barriers that might have affected adherence were taken into consideration.

Differential impacts of adiponectin on low-grade albuminuria between obese and nonobese persons without diabetes.

Abstract: The goal of this study was to examine the association between adiponectin and low-grade albuminuria in nondiabetic persons and whether it differed between obese and nonobese individuals. Urinary albumin excretion (UAE) was assessed by overnight collection in 157 participants. Overall, as anticipated, 24-hour systolic blood pressure and fasting glucose levels were independent determinants of UAE (β=0.254 and 0.176, respectively, P<.05). In obese persons (body mass index [BMI] ≥25 kg/m2; n=63), adiponectin value was a significant negative determinant of UAE (β=−0.256, P<.05) independent of blood pressure and glucose levels, whereas in nonobese participants (n=94) it was not. In an analysis of BMI and the median value of adiponectin (9.9 µg/mL), UAE was found to be significantly higher in obese persons with low adiponectin levels than in obese persons with high adiponectin levels (9.20 vs 5.11 µg/min; P<.05), even after adjustment for age, sex, blood pressure level, and glucose level. There was an inverse association between adiponectin and low-grade albuminuria in obese nondiabetic persons.

The efficacy and tolerability of nebivolol in hypertensive African American patients.

Abstract: Hypertensive African Americans often respond poorly to beta-blocker monotherapy, compared with whites. There is evidence, however, that suggests that this response may be different if beta-blockers with vasodilating effects are used. This 12-week, multi-center, double-blind, randomized placebo-controlled study assessed the antihypertensive efficacy and safety of nebivolol, a cardioselective, vasodilating beta1-blocker, at doses of 2.5, 5, 10, 20, or 40 mg once daily in 300 African American patients with stage I or II hypertension (mean sitting diastolic blood pressure [SiDBP] > or =95 mm Hg and < or =109 mm Hg). The primary efficacy end point was the baseline-adjusted change in trough mean SiDBP. After 12 weeks, nebivolol significantly reduced least squares mean SiDBP (P< or =.004) at all doses of 5 mg and higher and sitting systolic blood pressure (P< or =.044) at all doses 10 mg and higher, compared with placebo. The drug was safe and well-tolerated, with no significant difference in the incidence of adverse events compared with placebo. Nebivolol monotherapy provides antihypertensive efficacy, with few significant adverse effects, in hypertensive African Americans.

Masked hypertension definition, impact, outcomes: a critical review.

Abstract: The phenomenon of masked hypertension (MH) is defined as a clinical condition in which a patient's office blood pressure (BP) level is <140/90 mm Hg but ambulatory or home BP readings are in the hypertensive range. The prevalence in the population is about the same as that of isolated office hypertension; about 1 in 7 or 8 persons with a normal office BP level may fall into this category. The high prevalence of MH would suggest the necessity for measuring out-of-office BP in persons with apparently normal or well-controlled office BP. Reactivity to daily life stressors and behavioral factors such as smoking, alcohol use, contraceptive use in women, and sedentary habits can selectively influence MH. MH should be searched for in individuals who are at increased risk for cardiovascular complications including patients with kidney disease or diabetes. Individuals with MH have been shown to have a greater-than-normal prevalence of organ damage, particularly with an increased prevalence of metabolic risk factors, left ventricular mass index, carotid intima-media thickness, and impaired large artery distensibility compared with patients with a truly normal BP level in and out of the clinic or office. Also, outcome studies have suggested that MH increases cardiovascular risk, which appears to be close to that of in-office and out-of-office hypertension. The aim of this review was to define the entity of MH, to describe its prevalence in the general population, and to discuss its correlation with cardiovascular events.

Aldosterone and the Vasculature: Mechanisms Mediating Resistant Hypertension

Abstract: The renin-angiotensin-aldosterone system appears to be one of the key factors in the development of hypertensive vascular disease. Identification of mineralocorticoid receptors in the heart, vasculature, and brain has raised speculation that aldosterone may directly mediate its detrimental effects in these target organs independent of angiotensin II. Aldosterone increases vascular tone due to endothelial dysfunction and enhances the pressor response to catecholamines and up-regulation of angiotensin II receptors. It induces electrolyte transport over the vascular smooth cell membrane and plays a crucial role in vascular remodeling of small and large arteries. Moreover, aldosterone is involved in vascular injury and promotes collagen synthesis, which leads to increased arterial stiffness and elevation of blood pressure. Aldosterone has also been shown to exert a number of effects in the central nervous system. Several human studies have shown that aldosterone is related to baroreflex resetting. Thus, in cases of severe hypertension, there would be fewer compensatory mechanisms to offset blood pressure elevation and ensuing vascular damage. Endothelial and vascular smooth muscle cells have the potential to synthesize aldosterone, and tissue aldosterone could play a more important role in resistant hypertension and target organ damage than circulating aldosterone. Understanding aldosterone synthase polymorphism may provide insight into blood pressure patterns and their consequences. Understanding the vascular mechanisms of aldosterone in resistant hypertension may explain why selective aldosterone receptor blockers might have beneficial effects in resistant hypertension.

A Randomized, Double‐Blind, Placebo‐Controlled Parallel‐Group Study to Assess the Efficacy and Safety of Nebivolol, a Novel β‐Blocker, in Patients With Mild to Moderate Hypertension

Abstract: This double-blind, multicenter, randomized placebo-controlled study evaluated the antihypertensive efficacy and safety of nebivolol, a selective beta1-adrenoreceptor blocker with vasodilating effects, in patients with mild to moderate hypertension (sitting diastolic blood pressure [SiDBP] > or =95 mm Hg and < or =109 mm Hg). A total of 909 patients were randomized to receive placebo or nebivolol 1.25, 2.5, 5, 10, 20, or 40 mg once daily for up to 84 days. The primary end point was the change in trough SiDBP from baseline to study end. Nebivolol significantly reduced trough SiDBP (8.0-11.2 mm Hg compared with 2.9 mm Hg with placebo; P<.001) and trough sitting systolic blood pressure (a 4.4-9.5-mm Hg decrease compared with a 2.2-mm Hg increase [corrected] with placebo; P< or =.002). The overall adverse event experience was similar in the nebivolol (46.1%) and placebo (40.7%) groups (P=.273). Once-daily nebivolol is an effective antihypertensive in mild to moderate hypertensive patients.

Masked Hypertension in Diabetes Mellitus: A Potential Risk

Abstract: The prevalence and clinical significance of masked hypertension (MHT) in diabetics have infrequently been described. The authors assessed the association of MHT (defined using a clinic blood pressure [BP] or = 135/85 mm Hg) with microvascular and macrovascular end organ damage in 81 clinically normotensive Japanese diabetic persons. The prevalence of silent cerebral infarcts (SCIs), increased left ventricular mass, and albuminuria were evaluated. Of 81 patients, 38 (46.9%) were classified as having MHT and showed significantly more SCIs (mean +/- SE: 2.5+/-0.5 vs 1.1+/-0.2; P=.017), and more albuminuria (39% vs 16%; P=.025), but no increase in left ventricular mass index, than the normotensive persons in office and on ambulatory BP monitoring group. The prevalence of MHT in this diabetic population was high (47%). Diabetic patients with MHT showed evidence of brain and kidney damage. Hence, out-of-office monitoring of BP may be indicated in diabetics whose BP is normal in the clinic.

Understanding uncontrolled hypertension: is it the patient or the provider?

Abstract: The relative contributions of adherence and treatment intensity to blood pressure (BP) control are not well understood. The authors studied patients with uncontrolled hypertension (N=410) from 3 primary care clinics in the Veterans Affairs (VA) medical system. A questionnaire was used to assess patient adherence to therapy, and VA system pharmacy fills were used to assess the intensity of the antihypertensive regimen. At baseline, an inadequate antihypertensive regimen was implicated as the most probable reason for uncontrolled BP in a majority of patients (72%), while nonadherence could only be implicated in 13%. In multivariate longitudinal analyses, patients who had an increase in their medical treatment during the study had lower final diastolic BP levels compared with the patients who did not (-3.70 mm Hg; P<.05). While patient adherence to therapy plays a role, vigorous clinical management by the clinician is a more important contributor to BP control.

Resistant hypertension: prevalence and evolving concepts.

Abstract: Resistant hypertension is a common medical disorder. Although the exact incidence of resistant hypertension is not established, estimates derived from recent outcome studies including the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT), Valsartan Antihypertensive Long-term Use Evaluation (VALUE), and Controlled Onset Verapamil Investigation of Cardiovascular End Points (CONVINCE) emphasize that this condition may be more common than previously thought. A major advance in our understanding of the pathogenesis and management of resistant hypertension is the recognition of the importance of aldosterone. Several investigators have postulated a direct role of aldosterone excess as an important mechanism for drug resistance in hypertension. The mechanisms whereby aldosterone elevates BP are complex. It was previously thought that aldosterone produced hypertension primarily by promoting sodium retention with consequent hypervolemia. Recent studies of the effects of aldosterone on vascular smooth muscle have, however, delineated several extrarenal mechanisms whereby aldosterone produces hypertension-primarily by its direct vasoconstrictor effects and by altering vascular compliance. Consequently, aldosterone blockade constitutes an effective intervention for treating resistant hypertension.

Why Physicians Who Treat Hypertension Should Know More About Air Pollution

Abstract: Exposure to ambient levels of particulate matter (PM) air pollution increases the risk of a host of cardiovascular diseases and events. One potential mechanism explaining this association is that acute exposure to PM at high concentrations is capable of raising blood pressure within hours to days. Epidemiologic studies confirm that even commonly encountered levels of airborne pollutants can result in a prohypertensive response in humans. Several biologic pathways may be involved, including autonomic nervous system imbalance and arterial vascular dysfunction/vasoconstriction due to systemic oxidative stress/inflammation triggered by PM inhalation. The clinical importance of this vasopressor response and its relative role in promoting cardiovascular events associated with PM remain unclear. Because air pollution exposure is ubiquitous throughout the world, however, all health care providers and especially those who treat hypertension should be aware of this emerging and important biologic relationship.

24-Hour Blood Pressure Monitoring in the Evaluation of Supine Hypertension and Orthostatic Hypotension

Abstract: The presence of orthostatic hypotension has been shown to be a significant, independent predictor of all-cause mortality. Systolic and diastolic orthostatic hypotension, reversal of the circadian pattern, and postprandial hypotension are some of the hemodynamic factors that may contribute to the increased mortality seen in patients with orthostatic hypotension. The high variability of blood pressure in orthostatic hypotension cannot usually be adequately assessed by a one-time measurement. In this group of patients, 24-hour ambulatory blood pressure monitoring may be more useful.

Effects of Initial Antihypertensive Drug Class on Patient Persistence and Compliance in a Usual‐Care Setting in the United States

Abstract: Antihypertensive treatment regimen persistence and compliance were measured using a retrospective cohort study of pharmacy claims data. Newly treated patients receiving monotherapy with angiotensin II receptor blockers (ARBs), angiotensin-converting enzyme inhibitors (ACEIs), calcium channel blockers (CCBs), β-blockers (BBs), or diuretics were followed for 1 year (N=242,882). A higher proportion of ARB patients (51.9%) were persistent in taking prescribed medication compared with those in the ACEI (48.0%), BB (40.3%), CCB (38.3%), and diuretic groups (29.9%). Compared with patients receiving diuretics, those receiving ARBs (hazard ratio [HR], 0.593; P<.0001), ACEIs (HR, 0.640; P<.0001), CCBs (HR, 0.859; P<.0001), and BBs (HR, 0.819; P<.0001) were all less likely to discontinue therapy. Compliance was similar in ACEI and ARB patients, but patients receiving ARBs and ACEIs had better compliance than those receiving BBs, CCBs, or diuretics. The lesser degree of compliance and persistence observed in patients receiving diuretics compared with other antihypertensive medications may have public health as well as cost implications.

Microalbuminuria: What Is It? Why Is It Important? What Should Be Done About It? An Update

Abstract: Microalbuminuria (MA) is defined as a persistent elevation of albumin in the urine of >30 to 20 to 300 mg/d. Data support the concept that the presence of MA is the kidney's warning that there is a problem with the vasculature. The presence of MA is a marker of endothelial dysfunction and a predictor of increased cardiovascular risk. MA can be reduced, and progression to overt proteinuria prevented, by aggressive blood pressure reduction, especially with a regimen based on medications that block the renin-angiotensin-aldosterone system, and control of diabetes. The National Kidney Foundation recommends that blood pressure levels be maintained at or below 130/80 mm Hg in anyone with diabetes or kidney disease.

Low-dose aldosterone blockade as a new treatment paradigm for controlling resistant hypertension.

Abstract: Treatment of resistant hypertension requires confirmation of true resistance, diagnosis and treatment of secondary causes of hypertension, adoption of appropriate lifestyle modifications, and effective use of multidrug antihypertensive regimens. Excessive volume retention often underlies resistant hypertension, so diuretics are generally necessary to achieve blood pressure (BP) goals. Although treatment regimens consisting of 3 or more agents have not been systematically evaluated, the author has found a triple regimen consisting of a thiazide diuretic, a calcium channel blocker, and an angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) to be generally effective and well tolerated. Although hydrochlorothiazide is more widely used, chlorthalidone provides better BP reduction and should be preferentially used in patients with resistant hypertension, particularly if the patient remains uncontrolled on hydrochlorothiazide. Recent studies have demonstrated that low doses of aldosterone antagonists, when added to multi-drug regimens that include a thiazide diuretic and an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker, provide significant additional BP reduction, seemingly exceeding what would be expected with addition of alternative classes of agents. The degree of BP reduction induced by aldosterone blockade has been similar in patients with and without evidence of aldosterone excess. Aldosterone antagonists are generally safe and well tolerated. The most common adverse effect of low-dose spironolactone has been breast tenderness, occurring in about 10% of men. Hyperkalemia is uncommon, but can occur, necessitating biochemical monitoring. Risk of hyperkalemia is increased in patients with chronic kidney disease or diabetes, elderly patients, and patients already receiving an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker.

Statins and C-Reactive Protein Levels

Abstract: In patients with or at risk for cardiovascular disease (CVD), including hypertensive individuals, lowering levels of low-density lipoprotein cholesterol (LDL-C) reduces CVD risk. Statins are the most effective of available therapies for lowering LDL-C. Extensive clinical trial data have shown that the degree of LDL-C reduction obtained depends on the particular statin used and that intensive LDL-C lowering reduces the incidence of cardiovascular events compared with more moderate LDL-C lowering. More recent data suggest that effects independent of LDL-C lowering may also play a part in the reduction in cardiovascular events. C-reactive protein (CRP), a marker of inflammation, is a potential predictor of CVD risk, and statins reduce CRP levels by up to 60%. CRP reduction is independent of LDL-C lowering, and variation between statins in CRP reduction may play some role in CVD event reduction rates. At present, however, there are few outcome data relating to the cardiovascular benefits of reducing CRP.

Prevalence, Treatment, and Control of Hypertension in Primary Care: Gaps, Trends, and Opportunities

Abstract: Since most cases of hypertension are managed in family practice, estimates of the prevalence, treatment, and control in the primary care population are needed to adequately address the burden of hypertension in Canada as it has in other countries. The authors used a large primary care research database to determine the prevalence of hypertension between 2000 and 2003. Blood pressure recordings were used to estimate the rates of prevalence, treatment, and control of hypertension for the overall population and for important subgroups. The prevalence of hypertension was 17.3%, most patients had untreated hypertension (68.6%), and only 15.8% had blood pressure treated and controlled. Higher rates of treatment and control were observed among older adults, those with type II diabetes, and those with a previous myocardial infarction. Odds of achieving target blood pressure were significantly better when combination therapy vs monotherapy was used. The prevalence of hypertension in primary care is high and most patients remain untreated; however, increased risk appears to lead to better treatment and control.

Prehypertension and insulin resistance in a nationally representative adult population.

Abstract: Prehypertension is associated with increased risk of cardiovascular disease and progression to hypertension. Insulin resistance (IR) is also related to cardiovascular risk. It is unknown whether individuals with prehypertension also have higher IR. The purpose of this study was to examine the association between prehypertension and IR. The National Health and Nutrition Examination Survey 1999-2002 was used to determine odds of IR by fasting insulin level >12.2 microU/mL or homeostasis model assessment (HOMA) > or = 2.6 among nondiabetic adults aged 20 to 80 years across blood pressure categories. Compared with normotensives, odds of IR were over 60% higher for prehypertensive individuals by both IR measures: fasting insulin (odds ratio [OR], 1.67; 95% confidence interval [CI], 1.12-2.48) and HOMA (OR, 1.67; 95% CI, 1.22-2.30). After stratifying by sex, IR was associated with prehypertension in only men for both IR measures. In conclusion, prehypertension is associated with higher IR in men, which may confer additional cardiovascular disease risk.