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1.
J Hum Hypertens ; 21(5): 374-80, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17314999

RESUMEN

In the Valsartan Antihypertensive Long-Term Use Evaluation (VALUE) trial, the risk of new-onset diabetes was reported to be 23% lower among patients initiating therapy with valsartan versus amlodipine. The objective of our study was to examine whether this finding is generalizable to 'real-world' clinical practice. A retrospective cohort design and a large US health insurance database were employed for analyses. Study subjects included all hypertensive patients, aged >or=35 years, who were free from diabetes and who initiated treatment with valsartan (n=9999) or amlodipine (n=18 698) between January 1999 and March 2005. Unadjusted absolute risks of diabetes were 21.4 (95% confidence interval (CI) 18.9-24.3) and 26.3 (95% CI 24.3-28.3) per 1000 patient-years for valsartan and amlodipine, respectively; the corresponding relative risk (RR) for valsartan was 0.82 (95% CI 0.70-0.94). Multivariate analyses - controlling for age, sex, presence of hypercholesterolemia, cardiovascular disease and kidney disease, and pretreatment medical care expenditures - yielded similar results (RR=0.79, 95% CI 0.68-0.92). Our study thus corroborates the finding from VALUE that diabetes risk is lower for patients who receive valsartan versus amlodipine, and extends this finding to a 'real-world' setting.


Asunto(s)
Amlodipino/uso terapéutico , Antihipertensivos/uso terapéutico , Diabetes Mellitus/inducido químicamente , Diabetes Mellitus/epidemiología , Hipertensión/tratamiento farmacológico , Tetrazoles/uso terapéutico , Valina/análogos & derivados , Adulto , Anciano , Antihipertensivos/efectos adversos , Bases de Datos Factuales , Diabetes Mellitus/prevención & control , Diabetes Mellitus Tipo 2/inducido químicamente , Diabetes Mellitus Tipo 2/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Conducta de Reducción del Riesgo , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos/epidemiología , Valina/uso terapéutico , Valsartán
2.
Hypertension ; 20(3): 314-8, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1516950

RESUMEN

Blood pressure (BP) readings from a single clinic visit are often used in population studies investigating the genetic basis of BP. We examined first-degree relatives in the Tecumseh Blood Pressure study to compare heritability estimates of BP readings obtained in the clinic-office setting (the average of two seated readings) with self-reported home BP readings (the average of 14 readings) taken over a 1-week period. The hypothesis tested was that repeated BP readings obtained in the home over the 1-week period would have fewer artifacts (i.e., environmentally induced variability in BP) and thus would better estimate the true "basal" BP that, in turn, would improve heritability estimates. We and others assume that the true basal BP level is heritable. We therefore expected that this "true" BP, by reducing BP variability of offspring, would show a stronger between-sibling correlation and that it would correlate better to parental BP as measured in a clinic setting. Correlation coefficients were calculated between siblings in the present Tecumseh study using self-reported home BP and clinic BP readings. Among 380 siblings (average age, 31.4 years), correlation coefficients for the home readings were of the same magnitude as for office readings (home, r = 0.23, p less than 0.01; office, r = 0.24, p less than 0.01). When offspring clinic BP readings were compared with archived BP data on parents, the correlation between offspring clinic and parental clinic BP readings was stronger (r = 0.24, p less than 0.05) than the correlation of offspring home BP readings to parental clinic BP readings (r = 0.17, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Determinación de la Presión Sanguínea/métodos , Presión Sanguínea , Caracteres Sexuales , Adulto , Presión Sanguínea/fisiología , Salud de la Familia , Femenino , Servicios de Atención de Salud a Domicilio , Humanos , Masculino , Visita a Consultorio Médico , Padres
3.
Hypertension ; 21(5): 618-23, 1993 May.
Artículo en Inglés | MEDLINE | ID: mdl-8491496

RESUMEN

Inferences about the association between sympathetic overactivity and insulin resistance have been drawn from the infusion of sympathomimetic amines in supraphysiological doses. We used the isolated perfused human forearm to investigate the effect of reflex-induced sympathetic nervous system activation on the peripheral utilization of glucose in the skeletal muscles of 14 healthy men. Local hyperinsulinemia in the forearm (132 +/- 25 microunits/mL for 90 minutes) induced a significant increase in the utilization of glucose from baseline (16.4 +/- 3.1 mg.dL-1.min-1 per 100 mL forearm volume) to a plateau (85.7 +/- 15.1 mg.dL-1.min-1 per 100 mL forearm volume) between 40 and 60 minutes of insulin infusion but did not alter the utilization of oxygen. Reflex sympathetic nervous system activation was elicited by unloading of cardiopulmonary receptors with bilateral thigh cuff inflation to 40 mm Hg between 60 and 90 minutes of insulin infusion. Blood flow in the forearm was significantly decreased with inflation of thigh cuffs (average decrease of 19%, p < 0.0001). As a result of thigh cuff inflation, there was a reduction in the utilization of glucose (a decrease of 23%, p < 0.02), whereas oxygen utilization was unchanged. We find that an increase in sympathetic nervous system activation (within the normal range of physiological responses) can cause acute insulin resistance in the forearm of healthy volunteers. The reflex caused no change in oxygen utilization, but the same stimulus elicited a decrease in the utilization of glucose.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Antebrazo/fisiología , Resistencia a la Insulina/fisiología , Reflejo/fisiología , Sistema Nervioso Simpático/fisiología , Adolescente , Adulto , Anciano , Constricción , Femenino , Glucosa/metabolismo , Hemodinámica/efectos de los fármacos , Humanos , Inyecciones Intravenosas , Insulina/farmacología , Masculino , Persona de Mediana Edad , Consumo de Oxígeno/efectos de los fármacos , Muslo
4.
Hypertension ; 27(4): 854-8, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8613260

RESUMEN

Insulin sensitivity may be improved with the angiotensin-converting enzyme inhibitor captopril, suggesting that inhibition of angiotensin II (Ang II) improves insulin resistance. However, the administration of systemic Ang II has also been associated with an improvement in rather than worsening of glucose utilization. Since both stimulating and antagonizing the renin-angiotensin system improve glucose uptake and both angiotensin-converting enzyme inhibitors and intravenous Ang II elicit skeletal muscle vasodilation, it is conceivable that hemodynamic factors rather than a direct effect of either Ang II or angiotensin-converting enzyme inhibitors on skeletal muscle metabolism modulate the increase in glucose utilization. The direct effects of Ang II on glucose extraction in intact human skeletal muscle have not been previously described. We investigated the effects of local infusion of Ang II on glucose uptake in the forearm of 20 healthy subjects. With the use of the isolated insulin-perfused forearm model, local plasma insulin values were raised to 100 mU/mL over fasting values and maintained there for a 90-minute infusion period. After the first 60 minutes of insulin alone, Ang II was infused into the brachial artery for the last 30 minutes. Intra-arterial Ang II infusion caused a 38% decrease in forearm blood flow (P <.05) and 59% increase in the arteriovenous glucose gradients (P <.05) to maintain a steady glucose utilization (a decrease of 4%, P=NS). Thus, local Ang II infusion does not impair insulin-stimulated glucose utilization. Furthermore, glucose extraction increases to compensate for the decrease in forearm blood flow (as the Fick principle would predict for freely diffusible substances). We conclude that the described increase in glucose utilization from systemic infusion of Ang II and during angiotensin-converting enzyme inhibitor treatment is mediated by hemodynamic factors rather than a direct effect of Ang II on skeletal muscle metabolism.


Asunto(s)
Angiotensina II/administración & dosificación , Arterias/fisiología , Glucemia/fisiología , Antebrazo/irrigación sanguínea , Adulto , Arterias/efectos de los fármacos , Transporte Biológico/efectos de los fármacos , Femenino , Hemodinámica/efectos de los fármacos , Humanos , Masculino
5.
Hypertension ; 23(6 Pt 2): 1006-11, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8206583

RESUMEN

We used the insulin-perfused human forearm model to assess the effects of vasoconstriction induced with norepinephrine on the extraction of glucose in the forearm in two groups of healthy young volunteers. The norepinephrine findings were compared with a previously studied group in which vasoconstriction has been caused by reflex activation of the sympathetic nervous system. The aim of the study was to determine the relative importance of hemodynamic and receptor-mediated mechanisms of insulin resistance. Plasma insulin, arterial and venous glucose samples, and forearm blood flow were measured at 10-minute intervals during a 30-minute baseline, a 60-minute intra-arterial insulin infusion, and during 30 minutes of insulin infusion plus vasoconstriction. Group 1 (n = 14) had physiological vasoconstriction induced by inflation of bilateral thigh cuffs to 40 mm Hg to cause pooling of blood in the lower extremities and reflex vasoconstriction in the forearm; group 2 (n = 8) had intra-arterial infusion of norepinephrine to achieve the same degree of vasoconstriction as seen with inflation of thigh cuffs in group 1. Subjects in group 3 (n = 7) had infusion of intra-arterial norepinephrine to achieve a twofold increase in physiological vasoconstriction. With a physiological decrease in forearm blood flow (group 1), there was a 19% decrease in forearm blood flow resulting in a 23% reduction in glucose uptake in the forearm (P < .03). The same degree of reduction in forearm blood flow with a predominantly alpha-adrenergic agonist, norepinephrine (group 2), causes much less insulin resistance (a decrease in utilization of 13%) (P < .04).(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Antebrazo/irrigación sanguínea , Resistencia a la Insulina/fisiología , Norepinefrina/farmacología , Reflejo , Sistema Nervioso Simpático/fisiología , Vasoconstricción/fisiología , Adulto , Glucemia/metabolismo , Vasos Sanguíneos/efectos de los fármacos , Femenino , Antebrazo/fisiopatología , Humanos , Hiperinsulinismo/fisiopatología , Masculino , Flujo Sanguíneo Regional/efectos de los fármacos
6.
Hypertension ; 31(4): 1014-20, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9535429

RESUMEN

The Hypertension Optimal Treatment Study is a prospective trial conducted in 26 countries. The aims are to (1) evaluate the relationship between three levels of target office diastolic blood pressure (BP) (< or = 80, < or = 85, or < or = 90 mm Hg) and cardiovascular morbidity and mortality in hypertensive patients and (2) examine the effects on cardiovascular morbidity and mortality of 75 mg aspirin daily versus placebo. A total of 19,193 patients between 50 and 80 years of age had been randomized by the end of April 1994. Treatment was initiated with felodipine 5 mg daily, and additional therapy was given in accordance with a set protocol. The present substudy of 926 patients performed in nine countries aimed to (1) compare home with office BP in a representative subsample of the HOT population after the titration of treatment was completed and (2) clarify whether the separation into the target groups could be expanded into the out-of-office setting. The differences between office and home measurements in diastolic BP of 0.2 mm Hg (SD, 9; 95% confidence interval, -0.36 to 0.81; P=.40) and systolic BP of 0.5 mm Hg (SD, 15; 95% confidence interval, -0.53 to 1.46; P=.21) were not significant. The group differences in home BP were 1.9 mm Hg (< or = 80 versus < or = 85) and 1.2 mm Hg (< or = 85 versus < or = 90) for diastolic BP (F=11.69; ANOVA, P<.0001) and 2.6 and 2.1 mm Hg for systolic BP (F=8.44, P=.0002). Thus, office and home BPs measured with the same semiautomatic device are comparable in treated hypertensive subjects in the HOT Study, and the separation into the target groups based on office readings prevails at home.


Asunto(s)
Antihipertensivos/uso terapéutico , Determinación de la Presión Sanguínea , Presión Sanguínea/efectos de los fármacos , Hipertensión/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
7.
Am J Med ; 101(3A): 22S-32S, 1996 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-8876472

RESUMEN

The aim of this review is to assess the prevalence of complications and responses to various antihypertensive drug therapies in ethnic minority groups in the United States. In some instances, these comments are extended to responses of citizens in their countries of origin. The incidence of hypertension, mortality from hypertensive heart disease, stroke, and hypertensive renal disease are higher in African Americans. Although some Hispanic Americans have a lesser risk for hypertension, they have a greater risk for other risk factors such as diabetes and dyslipidemia. There is a similar association between income and mortality for both African Americans and Hispanic Americans. When compared to European Americans and other ethnic minorities, African Americans respond less favorably to beta blockers and angiotensin-converting enzyme (ACE) inhibitors. Nevertheless, the observed response in African Americans to ACE inhibitors and beta blockers is clinically significant. The available literature indicates that Asian American responses to calcium antagonists seem to be more favorable than responses to ACE inhibitors and equivalent to their responses to diuretic and beta blocker therapy. Although there are few published studies of drug efficacy in Hispanic Americans, there appears to be no hierarchy in response to the various antihypertensive drug classes. Ethnicity is not an accurate criterion for predicting poor response to any class of antihypertensive therapy. Thus, there is little justification to use racial profiling as a criterion for the avoidance of selected drug classes because of presumed lack of efficacy. Observed differences in the incidence of hypertension and its poor outcomes have led some investigators to postulate that the etiology of hypertension in ethnic minority groups is intrinsically different from whites. Awareness of racial differences in hypertension outcomes evolved in the United States within a historical context that does not fully appreciate that race is often a surrogate for many social and economic factors that influence health status and healthcare delivery. Poor outcomes in ethnic minority groups occur in many diseases, not only hypertension. The goal of ethnicity-related research should be to describe the diversity of disease expression in humans and to target at-risk groups for prevention and early intervention. The use of racial descriptors to explain genetic differences in ethnic groups should take a lesser priority.


Asunto(s)
Antihipertensivos/uso terapéutico , Etnicidad , Hipertensión/etnología , Asiático , Población Negra , Accesibilidad a los Servicios de Salud , Hispánicos o Latinos , Humanos , Hipertensión/tratamiento farmacológico , Indígenas Norteamericanos , Estados Unidos
8.
J Hypertens ; 12(4): 455-62, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8064170

RESUMEN

OBJECTIVE: To investigate the relationship between hematocrit, blood pressure and other known cardiovascular risk factors. DESIGN: The Tecumseh Blood Pressure Study includes a cohort of subjects of average age 29.5 years (346 male, 277 female) who reside in Tecumseh, Michigan, USA. METHODS: The body weight; home, work and clinic blood pressures; hematocrit level, plasma renin activity, baseline and mentally stimulated plasma catecholamines level; and fasting glucose, insulin and lipids levels were obtained. Since menstruation and childbearing affect the hematocrit, results are presented only for males. The males in Tecumseh were divided into tertiles of hematocrit (group I < or = 43.25, group II 43.26-45.2 and group III > 45.2%). RESULTS: Higher hematocrit levels were significantly related to higher blood pressures at home, at work and in the clinic, although all of the values measured were within the normotensive range (128/79 mmHg clinic blood pressure in group III). The metabolic factors weight, cholesterol, triglycerides, insulin and glucose levels were significantly elevated in group III. The weight affected only the relationship of hematocrit to plasma insulin levels and not the other variables including the blood pressure. Groups II and III showed signs of sympathetic overactivity; their plasma renin levels, heart rates and norepinephrine levels after mental stimulation were elevated. CONCLUSIONS: Although the relationship of blood pressure to the hematocrit level was previously known, in Tecumseh hematocrit is also found to be associated with several other cardiovascular risk factors and with signs of a hypersympathetic state. We intend to evaluate prospectively the relative prognostic significance of a higher hematocrit level versus the other associated risk factors.


Asunto(s)
Enfermedades Cardiovasculares/epidemiología , Hematócrito , Adulto , Envejecimiento/fisiología , Presión Sanguínea , Peso Corporal , Estudios de Cohortes , Femenino , Humanos , Masculino , Análisis de Regresión , Factores de Riesgo , Sistema Nervioso Simpático/fisiopatología
9.
Am J Hypertens ; 9(8): 60s-64s, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8862239

RESUMEN

In the past 20 years, clinicians have clearly demonstrated that antihypertensive therapy is very effective in reducing the incidence of myocardial infarction and stroke. However, little is known about the effects of blood pressure reduction on end stage renal disease (ESRD). Data from major clinical studies has clearly shown that patients with hypertension have an increased risk of developing ESRD. Black men and women with hypertension are at the greatest risk; however, the incidence of ESRD is increasing in all racial groups. Because patients with hypertensive ESRD often require dialysis, the cost of treating this increasing common disorder has the potential to deplete the Medicare system. The primary effect of blood pressure reduction in patients with ESRD has not been adequately addressed in any trial that has been completed to date. Results from some studies suggest that blood pressure reduction may improve renal function and that angiotensin converting enzyme inhibitors and calcium channel blockers may have renoprotective effects. Currently in progress are two large scale clinical trials that may provide more information on the effects on antihypertensive therapy on preventing ESRD in hypertensive patients. These are the African American Study of Kidney Disease and Hypertension (AASK), and a substudy of the Hypertension Optimal Treatment (HOT) Study. Data from the HOT study is expected to be available 5 years prior to that of the ASK Study, which is expected to be completed by the Year 2002.


Asunto(s)
Antihipertensivos/uso terapéutico , Fallo Renal Crónico/prevención & control , Femenino , Humanos , Fallo Renal Crónico/epidemiología , Masculino , Factores de Riesgo
10.
Am J Hypertens ; 4(11): 598S-602S, 1991 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-1789939

RESUMEN

Early intervention in the treatment of hypertension can reduce the detrimental effects of high blood pressure. Therefore it is important to be able to predict the development of hypertension in individuals. A number of factors can be used as predictors of hypertension, but only childhood high blood pressure (especially in combination with obesity) is a potent predictor of future hypertension. A family history of hypertension is a contributory risk factor, as is tachycardia, but neither is as strong a predictor as a youthful elevated pressure.


Asunto(s)
Presión Sanguínea/fisiología , Hipertensión/epidemiología , Hipertensión/fisiopatología , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Valor Predictivo de las Pruebas
11.
Am J Hypertens ; 13(5 Pt 2): 68S-73S, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10830792

RESUMEN

Successful treatment of hypertension entails not only normalizing high blood pressure, but also addressing the associated risk factors that increase the likelihood of cardiovascular morbidity and mortality. Hypertension often occurs in a setting of insulin resistance, hyperinsulinemia, dyslipidemia, and a prothrombotic state. A number of epidemiologic studies have shown that the clustering of these abnormalities is associated with increased risk of cardiovascular morbidity and mortality. Therefore, it is rational to direct therapy at moderating these risk factors as well as at lowering blood pressure in hypertensive patients. This is particularly important in patients with comorbidities such as diabetes, cardiovascular disease, or renal insufficiency. Many physicians prescribe only diuretics and beta-blockers, agents that have demonstrated efficacy in long-term randomized controlled trials. However, this approach does not consider the potential benefits of newer agents for which long-term outcome data are not yet available. The ongoing Valsartan Antihypertensive Long-term Use Evaluation (VALUE) trial, in which the angiotensin II subtype 1 receptor blocker valsartan is compared with the third-generation calcium channel blocker amlodipine, should provide important evidence on the long-term efficacy of these newer agents. A unique feature of VALUE is that it is specifically enrolling into the only current trial, now under way, hypertensive men and women at a relatively high risk for a cardiovascular event to determine the benefits of complete blockade of angiotensin II beyond those of the control of blood pressure.


Asunto(s)
Antihipertensivos/uso terapéutico , Hipertensión/tratamiento farmacológico , Hipertensión/epidemiología , Humanos , Factores de Riesgo
12.
Am J Hypertens ; 10(11): 1270-80, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9397247

RESUMEN

We evaluated time-related blood pressure trends in the Tecumseh study participants, none of whom received antihypertensive treatment. At baseline the blood pressures were measured in the field clinic and by self measurement at home (twice daily for 7 days). After a mean of 3.2 +/- 0.42 years, the clinic and home pressure readings were repeated. Nine hundred forty-six subjects had clinic and home blood pressure readings at baseline. Of these 735 (380 men, 355 women; average age, 32 years) also completed the second examination. Blood pressure, morphometric data, and biochemical measures at the first examination were used as predictors of future clinic blood pressures. Five hundred ninety-six subjects were normotensive on both examinations (81%). Of 79 subjects (10.7%) with clinic hypertension (> 140 mg Hg systolic or 90 mm Hg diastolic) at baseline, 38 remained hypertensive ("sustained hypertension") and 41 became normotensive ("transient hypertension") after 3 years. Another 60 normotensives at baseline (10.4%) became hypertensive on second examination ("de novo hypertensives"; incidence; 8.1%). The home blood pressure readings on both examinations were reproducible. The three hypertensive groups had elevated home blood pressure, were overweight, had dyslipidemia, and higher insulin values. Only the home blood pressure proved predictive of subsequent blood pressure trends. A home blood pressure of 128 and 83 mm Hg or higher detected "sustained" hypertension with a 48% sensitivity and 93% specificity. Readings of 120 and 80 mm Hg or lower predicted future normotension with a 45% sensitivity and a 91% specificity. We conclude that self determination of the blood pressure at home is useful in the management of borderline hypertension. An algorithm for the management of these patients is proposed.


Asunto(s)
Presión Sanguínea/fisiología , Hipertensión/fisiopatología , Adolescente , Adulto , Algoritmos , Peso Corporal , Femenino , Estudios de Seguimiento , Hemodinámica/fisiología , Hormonas/sangre , Humanos , Hipertensión/complicaciones , Hipertensión/diagnóstico , Resistencia a la Insulina/fisiología , Masculino , Obesidad/complicaciones , Obesidad/fisiopatología , Pronóstico
13.
J Neurosurg ; 88(2): 226-31, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9452228

RESUMEN

OBJECT: The authors designed a blinded prospective study comparing patients with essential hypertension to patients without hypertension in which magnetic resonance (MR) imaging was used to evaluate the role of lateral medullary compression by adjacent vascular structures as a cause of neurogenic hypertension. METHODS: Patients with documented essential hypertension were recruited to undergo thin-slice axial brainstem MR imaging evaluation. Nonhypertensive (control) patients scheduled to undergo MR imaging for other reasons also underwent thin-slice MR imaging to form a basis for comparison. Magnetic resonance images obtained in patients from the hypertensive (30 patients) and the control (45 patients) groups were then compared by four independent reviewers (two neuroradiologists and two neurosurgeons) who were blinded to the patients' diagnosis and hypertensive status. Images were reviewed with regard to left versus right vertebral artery (VA) dominance, compression of the medulla on the left and/or right side, and brainstem rotation. Medullary compression was graded as either vessel contact without associated brainstem deformity or vessel contact with associated brainstem deformity. CONCLUSIONS: There was a tendency toward left VA dominance in the hypertensive group compared with the control group, although a significant difference was shown by only one of the four reviewers. There were no differences in brainstem compression or rotation between the hypertensive and nonhypertensive groups. These results are contrary to those of recently published studies in which MR imaging and/or MR angiography revealed lateral brainstem vascular compression in hypertensive patients but not in nonhypertensive (control) patients. Reasons for this discrepancy are discussed. On the basis of their own experience and that of others, the authors believe that neurogenic hypertension does exist. However, thin-slice MR imaging may not be a reliable method for detecting neurovascularly induced essential hypertension and the prevalence of neurovascular compression as the source of hypertension may be overestimated when using current imaging techniques.


Asunto(s)
Hipertensión/patología , Hipertensión/cirugía , Bulbo Raquídeo/patología , Bulbo Raquídeo/cirugía , Adolescente , Adulto , Anciano , Tronco Encefálico/patología , Estudios de Evaluación como Asunto , Femenino , Humanos , Hipertensión/etiología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Síndromes de Compresión Nerviosa/complicaciones , Síndromes de Compresión Nerviosa/patología , Variaciones Dependientes del Observador , Estudios Prospectivos , Rotación , Método Simple Ciego , Arteria Vertebral/patología
14.
Ethn Dis ; 8(1): 120-3, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9595256

RESUMEN

When initiating monotherapy for the treatment of essential hypertension, multiple determinants factor into the decision. The goal of treatment is to lower blood pressure and lessen the likelihood of progression to target organ failure. Physicians frequently prioritize these determinants and make decisions to initiate monotherapy based on the race of an individual. All too often, however, the black/white issue is overstated and given too much consideration. The overall goal of this review is to suggest the appropriate "role" for racial profiling in the initial selection of an antihypertensive agent.


Asunto(s)
Población Negra , Bloqueadores de los Canales de Calcio/uso terapéutico , Hipertensión/tratamiento farmacológico , Hipertensión/etnología , Negro o Afroamericano , Ensayos Clínicos como Asunto , Humanos , Hipertensión/fisiopatología , Estilo de Vida , Volumen Plasmático , Perfil de Impacto de Enfermedad , Estados Unidos/epidemiología
15.
Ethn Dis ; 2(3): 232-45, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1467760

RESUMEN

This study examines the influence of ethnicity (African-American vs white) and family history of hypertension on the blood pressure and heart rate responses of healthy, unmedicated men, aged 21 to 39 years, to a variety of stressors that are hypothesized to elicit beta-adrenergic or alpha-adrenergic reactivity. Cardiovascular reactivity data were also obtained in response to ischemic exercise (handgrip), and a structured interview was designed to measure anger. On the basis of previous research, we predicted that African Americans would show greater responses to the alpha-adrenergic tasks (cold pressor test) and smaller cardiovascular responses to the beta-adrenergic tasks (math challenge) compared to whites. The results indicated no significant differences between African-American and white blood pressure or heart rate responses to either of the tasks. On the other hand, both African-American and white men with family histories of hypertension had significantly higher systolic and diastolic blood pressure responses during exposure to each of the stressors than did men with negative family histories of hypertension. Parental history did not significantly influence heart rate responses to the stressors or resting plasma catecholamine levels in either group. African Americans had significantly lower erythrocyte lithium-sodium exchange rates and significantly higher intracellular sodium concentration compared to whites; parental history of hypertension did not influence these measures. Finally, the blood pressure responses to stress were not modified by the erythrocyte lithium-sodium exchange rate, intracellular sodium concentration, or plasma concentrations of catecholamines.


Asunto(s)
Población Negra , Negro o Afroamericano , Sistema Cardiovascular/fisiopatología , Hipertensión/epidemiología , Estrés Psicológico/complicaciones , Población Blanca , Adulto , Catecolaminas/sangre , Estudios de Evaluación como Asunto , Hemodinámica , Hospitales Universitarios , Humanos , Hipertensión/diagnóstico , Hipertensión/etiología , Líquido Intracelular/química , Masculino , Michigan/epidemiología , Sodio/química , Estrés Psicológico/fisiopatología , Estrés Psicológico/psicología
16.
J Hum Hypertens ; 24(7): 483-91, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20010618

RESUMEN

This prospective, 6-week, multicenter, double-blind study examined the benefits of initiating treatment with combination valsartan/hydrochlorothiazide (HCTZ) compared with initial valsartan monotherapy for 648 patients with stage-1 or stage-2 hypertension (age=52.6+/-10 years; 54% male; baseline blood pressure (BP)=161/98 mm Hg, 32% stage 1). Patients were randomized to valsartan 80 mg (V-low), valsartan 160 mg (V-high) or valsartan/HCTZ 160/12.5 mg (V/HCTZ), and electively titrated after weeks 2 and 4 to the next dosage level (maximum dose valsartan/HCTZ 160/25 mg) if BP remained >140/90 mm Hg. At end of the study, patients initiated with V/HCTZ required less titration steps compared with the initial valsartan monotherapy groups (63 vs 86% required titration by study end, respectively) and reached the target BP goal of <140/90 mm Hg in a shorter period of time (2.8 weeks) (P<0.0001) vs V-low (4.3 weeks) and V-high (3.9 weeks). Initial combination therapy was also associated with higher BP control rates and greater reductions in both systolic and diastolic BP from baseline (63%, -27.7+/-13/-15.1+/-8 mm Hg) compared with V-low (46%, -21.2+/-13/-11.4+/-8 mm Hg, P<0.0001) or V-high (51%, -24.0+/-13/-12.0+/-10 mm Hg, P<0.01). Overall and drug-related AEs were mild to moderate and were similar between V/HCTZ (53.1 and 14.1%, respectively) and the two monotherapy groups, V-low (50.5 and 13.8%) and V-high (50.7 and 11.8%). In conclusion, initiating therapy with a combination of valsartan and low-dose HCTZ results in early, improved BP efficacy with similar tolerability as compared with starting treatment with a low or higher dose of valsartan for patients with stage-1 and stage-2 hypertension.


Asunto(s)
Antihipertensivos/administración & dosificación , Hidroclorotiazida/administración & dosificación , Hipertensión/tratamiento farmacológico , Tetrazoles/administración & dosificación , Valina/análogos & derivados , Adulto , Anciano , Antihipertensivos/efectos adversos , Quimioterapia Combinada , Femenino , Humanos , Hidroclorotiazida/efectos adversos , Masculino , Persona de Mediana Edad , Tetrazoles/efectos adversos , Resultado del Tratamiento , Valina/administración & dosificación , Valina/efectos adversos , Valsartán
19.
Am J Kidney Dis ; 36(3 Suppl 1): S24-30, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10986156

RESUMEN

African Americans outrank other ethnic groups in the United States in prevalence, early onset, and severity of hypertension. Furthermore, African Americans suffer the highest rates of mortality from cardiovascular, cerebrovascular, and end-stage renal disease. The recently concluded Heart Outcomes Prevention Evaluation (HOPE) study reports that the angiotensin-converting enzyme (ACE) inhibitor ramipril significantly reduced morbidity and mortality in a broad range of patients at high risk for cardiovascular events. These results strengthen the case for increasing the use of ACE inhibitor therapy. In accord with the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC VI) guidelines, antihypertensive monotherapy for African Americans is based on the known ability of diuretics and calcium channel blockers to produce greater reductions in blood pressure in this population than those attainable with beta blockers and ACE inhibitors. The national guidelines also suggest ACE inhibitors for all hypertensive patients with left ventricular dysfunction or nephropathy, which implies that African Americans must cross a clinical threshold to become candidates for these agents. The rationale for delaying ACE inhibitor therapy is due in part to a perceived unique pathobiology in hypertensive African Americans: an excess prevalence of salt sensitivity, hypervolemia, and low plasma renin activity (PRA). At first glance, it would seem intuitive to avoid agents that further depress the renin-angiotensin system (RAS) and choose agents that reduce plasma volume. However, most hypertensive African Americans are not hypovolemic. Furthermore, dietary sodium restriction and diuretic therapy raise PRA and improve the response to ACE inhibitors. The overall aim of this article is to explain the rationale for expanded use of drugs that block the RAS in African Americans and low-renin populations.


Asunto(s)
Angiotensina II/antagonistas & inhibidores , Antagonistas de Receptores de Angiotensina , Hipertensión/tratamiento farmacológico , Renina/sangre , Antagonistas Adrenérgicos beta/uso terapéutico , Negro o Afroamericano , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Antihipertensivos/uso terapéutico , Población Negra , Presión Sanguínea/efectos de los fármacos , Volumen Sanguíneo/fisiología , Bloqueadores de los Canales de Calcio/uso terapéutico , Dieta Hiposódica , Diuréticos/uso terapéutico , Etnicidad , Humanos , Hipertensión/etnología , Ramipril/uso terapéutico , Factores de Riesgo , Estados Unidos
20.
Clin Exp Hypertens ; 15(6): 979-95, 1993 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8268902

RESUMEN

The aim of this review is to compare the prevalence of complications and response to different treatment for hypertension in African and European Americans. African Americans when compared to European Americans respond less favorably to beta-blockers (BB's) and angiotensin converting enzyme inhibitors (ACEI's). Nevertheless the observed response of African Americans to ACEI's and BB's is significant and these agents are very effective in this subgroup. African American race is not a clinically significant predictor of poor response to any class of antihypertensive therapy and there is little justification to use racial profiling as a criterion for choice of medication. Evidence to restrict or defer usage of BB's and ACEI's in African Americans is lacking. The mortality from hypertensive heart disease, stroke, and the incidence of hypertensive renal disease is higher in African Americans which leads some investigators to postulate that hypertension in African Americans is intrinsically different from whites. They therefore search for a separate etiology and suggest specific approaches to treatment. Awareness of racial differences in hypertension outcomes evolved in the U.S. in an historical context that does not fully appreciate that race is often a surrogate for many social and economic factors that influence health status and health care delivery in the U.S. Poor outcomes in African Americans occur in many diseases including hypertension.


Asunto(s)
Antihipertensivos/uso terapéutico , Población Negra , Hipertensión/complicaciones , Hipertensión/etnología , Población Blanca , Ensayos Clínicos como Asunto , Humanos , Prevalencia , Estados Unidos/etnología
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