To determine the prognostic significance of ambulatory blood pressure, we prospectively followed for up to 7.5 years (mean, 3.2) 1187 subjects with essential hypertension and 205 healthy normotensive control subjects who had baseline off-therapy 24-hour noninvasive ambulatory blood pressure monitoring. Prevalence of white coat hypertension, defined by an average daytime ambulatory blood pressure lower than 131/86 mm Hg in women and 136/87 mm Hg in men in clinically hypertensive subjects, was 19.2%. Cardiovascular morbidity, expressed as the number of combined fatal and nonfatal cardiovascular events per 100 patient-years, was 0.47 in the normotensive group, 0.49 in the white coat hypertension group, 1.79 in dippers with ambulatory hypertension, and 4.99 in nondippers with ambulatory hypertension. After adjustment for traditional risk markers for cardiovascular disease, morbidity did not differ between the normotensive and white coat hypertension groups (P = .83). Compared with the white coat hypertension group, cardiovascular morbidity increased in ambulatory hypertension in dippers (relative risk, 3.70; 95% confidence interval, 1.13 to 12.5), with a further increase of morbidity in nondippers (relative risk, 6.26; 95% confidence interval, 1.92 to 20.32). After adjustment for age, sex, diabetes, and echocardiographic left ventricular hypertrophy (relative risk versus subjects with normal left ventricular mass, 1.82; 95% confidence interval, 1.02 to 3.22), cardiovascular morbidity in ambulatory hypertension was higher (P = .0002) in nondippers than in dippers in women (relative risk, 6.79; 95% confidence interval, 2.45 to 18.82) but not in men (P = .91). Our findings suggest that ambulatory blood pressures stratifies cardiovascular risk in essential hypertension independent of clinic blood pressure and other traditional risk markers including echocardiographic left ventricular hypertrophy.(ABSTRACT TRUNCATED AT 250 WORDS)

Ambulatory blood pressure. An independent predictor of prognosis in essential hypertension.

Natriuretic peptides are a family of structurally related but genetically distinct hormones/paracrine factors that regulate blood volume, blood pressure, ventricular hypertrophy, pulmonary hypertension, fat metabolism, and long bone growth. The mammalian members are atrial natriuretic peptide, B-type natriuretic peptide, C-type natriuretic peptide, and possibly osteocrin/musclin. Three single membrane-spanning natriuretic peptide receptors (NPRs) have been identified. Two, NPR-A/GC-A/NPR1 and NPR-B/GC-B/NPR2, are transmembrane guanylyl cyclases, enzymes that catalyze the synthesis of cGMP. One, NPR-C/NPR3, lacks intrinsic enzymatic activity and controls the local concentrations of natriuretic peptides through constitutive receptor-mediated internalization and degradation. Single allele-inactivating mutations in the promoter of human NPR-A are associated with hypertension and heart failure, whereas homozygous inactivating mutations in human NPR-B cause a form of short-limbed dwarfism known as acromesomelic dysplasia type Maroteaux. The physiological effects of natriuretic peptides are elicited through three classes of cGMP binding proteins: cGMP-dependent protein kinases, cGMP-regulated phosphodiesterases, and cyclic nucleotide-gated ion channels. In this comprehensive review, the structure, function, regulation, and biological consequences of natriuretic peptides and their associated signaling proteins are described.

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Natriuretic peptides, their receptors, and cyclic guanosine monophosphate-dependent signaling functions.

Background In cross-sectional studies, ambulatory blood pressure (ABP) correlates more closely than clinic BP with the organ damage of hypertension. Whether ABP predicts development or regression o...

Ambulatory Blood Pressure Is Superior to Clinic Blood Pressure in Predicting Treatment-Induced Regression of Left Ventricular Hypertrophy

Recommendations for the use of home (self) and ambulatory blood pressure monitoring. American Society of Hypertension Ad Hoc Panel.

It remains unclear whether preemptive transplantation is beneficial, and if so, who benefits. A total of 38,836 first, kidney-only transplants between 1995 and 1998 were retrospectively studied. A surprising 39% of preemptive transplants were from cadaver donors, and the proportions of cadaver donor transplants that were preemptive changed little, from 7.3% in 1995 to 7.7% in 1998. Preemptive transplants using cadaver donors were more likely among recipients aged 0 to 17 yr versus 18 to 29 yr (odds ratio [OR], 2.48; 95% confidence interval [CI], 1.94 to 3.17), white versus black (OR, 2.33; 95% CI, 2.03 to 2.68), able to work versus unable to work (OR, 1.42; 95% CI, 1.26 to 1.61), covered by private insurance versus Medicare (OR, 4.77; 95% CI, 4.26 to 5.32), or recipients with a college degree versus no college degree (OR, 1.34; 95% CI, 1.17 to 1.54). Preemptive transplants were less likely for Hispanics versus non-Hispanics (OR, 0.57; 95% CI, 0.50 to 0.67), patients with type 2 versus type 1 diabetes (OR, 0.76; 95% CI, 0.61 to 0.96), and for 2 to 5 HLA mismatches compared with 0 HLA mismatches (OR range, 0.77 to 0.82). In adjusted Cox proportional hazards analysis, the relative risk of graft failure for preemptive transplantation was 0.75 (0.67 to 0.84) among 25,758 cadaver donor transplants and 0.73 (0.64 to 0.83) among 13,078 living donor transplants, compared with patients who received a transplant after already being on dialysis. Preemptive transplantation was associated with a reduced risk of death: 0.84 (0.72 to 0.99) for cadaver donor transplants and 0.69 (0.56 to 0.85) for living donor transplants. Thus, preemptive transplantation, which is associated with improved patient and graft survival, is less common among racial minorities, those who have less education, and those who must rely on Medicare for primary payment. Alterations in the payment system, emphasis on early referral, and changes in cadaver kidney allocation could increase the number of patients who benefit from preemptive transplantation.

/pdf/preemptive-kidney-transplantation-the-advantage-and-the-27s5476yjs.pdf

Preemptive Kidney Transplantation: The Advantage and the Advantaged

During a survey of young subjects not receiving treatment for hypertension in Tecumseh, Michigan, clinic and self-monitored blood pressures taken at home (14 readings in 7 days) were obtained in 737 subjects (387 men, 350 women, average age 31.5 years). Hypertension in the clinic was diagnosed if the clinic blood pressure exceeded 140 mm Hg systolic or 90 mm Hg diastolic. In the absence of firm criteria for what constitutes hypertension at home, subjects whose average home blood pressure was in the upper decile of the whole population were considered to have hypertension at home. By these criteria, 7.1% of the whole population had "white coat" hypertension (i.e., high clinic but not elevated home readings). The prevalence of "sustained" hypertension (i.e., high readings in the clinic and at home) was 5.1%. Subjects with white coat and sustained borderline hypertension in Tecumseh were very similar. Both groups showed, at previous examinations (at ages 5, 8, 21, and 23 years), significantly higher blood pressure readings than the normotensive subjects. As young adults (average age 33.3 years), the parents of both hypertensive groups had significantly higher blood pressure readings than the parents of normotensive subjects. Both hypertensive groups had faster heart rates, higher systemic vascular resistance, and higher minimal forearm vascular resistance. Both hypertensive groups were more overweight, had higher plasma triglycerides, insulin, and insulin/glucose ratios than normotensive subjects. The white coat hypertensive group also had lower values of high density lipoprotein than the normotensive group. White coat hypertension is a frequent condition.(ABSTRACT TRUNCATED AT 250 WORDS)

"White coat" versus "sustained" borderline hypertension in Tecumseh, Michigan.

Synthetic atrial natriuretic factor (ANF) was administered in ascending doses (0.03, 0.20, 0.45 microgram/kg/min) to eight mildly essential hypertensive men on high (200 mEq/day) or low (10 mEq/day) sodium diets. Responses of blood pressure, heart rate, urinary volume and electrolyte excretion, renin, and aldosterone were measured. For the entire group, ANF lowered blood pressure and increased heart rate during the 0.20 and 0.45 microgram/kg/min infusions, and the antihypertensive effect of the peptide persisted for at least 2 hours after the infusions ended. Four patients (2 at 0.20 microgram/kg/min and 2 at 0.45 microgram/kg/min) experienced sudden bradycardia and hypotension at the end of or shortly after completion of ANF infusion. Renal excretion of water, sodium, chloride, calcium, and phosphorus increased in a dose-dependent fashion in response to infused ANF. Patients on the 200 mEq/day sodium diet had greater increases in urinary volume (11.1 +/- 2.8 vs 3.0 +/- 2.0 ml/min; p less than 0.05), sodium (870 +/- 134 vs 303 +/- 27 microEq/min; p less than 0.05), and chloride (801 +/- 135 vs 176 +/- 75 microEq/min; p less than 0.02) compared with patients on the low sodium diet. The apparent direct suppressive effect of a 0.03 microgram/kg/min infusion of ANF on renin and aldosterone levels was overcome at higher doses by counterregulation provoked by the depressor action. Renin was slightly (-12%) suppressed during the 0.03 microgram/kg/min infusion of ANF but increased at the 0.20 (+50%) and 0.45 microgram/kg/min (+90%; p less than 0.03) rates. Aldosterone declined significantly during the 0.03 microgram/kg/min infusion (-45%; p less than 0.01) of ANF but not during the two higher dose infusions.(ABSTRACT TRUNCATED AT 250 WORDS)

Antihypertensive and hypotensive effects of atrial natriuretic factor in men.

Recovery from end-stage renal disease.

Patients with borderline hypertension typically show enhanced sympathetic and decreased parasympathetic tone, characteristic personality traits (submissiveness, hostility) and hyperreactivity to mental stress. It has been proposed that the hypertensive personality results in a persistent 'defence reaction', enhancing sympathetic outflow from the central nervous system and reactivity to stress. But evidence from pharmacological intervention trials suggests that blood pressure reactivity is controlled independently of average baseline blood pressure. A study comparing the effects of the centrally-acting alpha 2-agonist, clonidine, and the selective beta 1-blocker, atenolol, demonstrated that both drugs had a comparable antihypertensive action on baseline blood pressure. However, neither agent affected stress responses to mental arithmetic, submaximal isometric handgrip exercise or cold pressor testing. We conclude that studies of stress reactivity, while of interest to students of circulatory control, are unlikely to yield insights into the causes of human hypertension.

Mohamed A. Sekkarie

Papers

"White coat" versus "sustained" borderline hypertension in Tecumseh, Michigan.

Antihypertensive and hypotensive effects of atrial natriuretic factor in men.

Recovery from end-stage renal disease.

Behaviour and hypertension: a pathophysiological puzzle.

Continuing kidney care in conflicts