Association of waist circumference with risk of hypertension and type 2 diabetes in Nigerians, Jamaicans, and African-Americans

OBJECTIVE: Prior studies have supported that waist circumference correlates better with visceral adipose tissue and is a better predictor of cardiovascular disease than are BMI and waist-to-hip ratio. In this study, we reexamine the role of waist size on the risk of hypertension and type 2 diabetes in African-origin populations from three contrasting environments. RESEARCH DESIGN AND METHODS: A cross-sectional survey was conducted of 5,042 men and women 25-74 years of age from Nigeria, Jamaica, and the U.S. The relationship between waist, blood pressure, and fasting blood glucose was assessed using multiple linear regression analyses. Logistic regression analyses using sex-specific empirical waist cut-points were used to determine the risks of hypertension and type 2 diabetes. RESULTS: Waist circumference was positively correlated with blood pressure and fasting blood glucose (P < 0.05). Increasing waist quartiles were significantly associated with higher risks of hypertension in the three populations, as estimated from age-adjusted odds ratios obtained from sex-specific logistic regression models. A highly elevated risk of type 2 diabetes-10-fold for Jamaican men and 23-fold for African-American women-was observed in the comparison of lowest to highest quartiles of waist circumference. CONCLUSIONS: Substantial reduction in hypertension and diabetes in men and women is achievable if the waist size is decreased in these populations. Intervention programs designed to reduce waist circumference through lifestyle modification, including exercise and diet, may have significant public health significance in reducing the incidence of hypertension and adult-onset diabetes in these populations.     

Repair of nonsevere rheumatic aortic valve disease during other valvular procedures: is it safe?

Many studies have suggested that African Americans have a higher prevalence of hypertension than whites. The authors conducted a prospective study of hypertension incidence from 1987-1988 to 1994-1995 in 140 African American and 237 white adults aged 30 to 54 years at baseline. The study participants were screened for participation in the Trials of Hypertension Prevention, phase 1, an 18-month lifestyle modification intervention trial aimed at lowering blood pressure, at the Baltimore Clinical Center. Baseline age, blood pressure, body mass index, and heart rate were similar in the two groups. Compared with whites, however, African Americans had a lower percentage of men, college graduates, and households with an income > or = $40,000 per year. African Americans also had lower mean urinary sodium to creatinine ratio and potassium to creatinine ratio, but a similar sodium to potassium ratio. The incidence of hypertension (blood pressure > or = 160/95 mm Hg and/or taking antihypertensive medication) over 7 years of follow-up was nearly identical: 25.7% in African Americans and 25.3% in whites. Baseline age, gender, blood pressure, and heart rate were all associated with the incidence of hypertension. Even after adjustment for these covariables, the risk of hypertension was not higher in African Americans compared with whites. These results indicate that middle-aged African Americans and whites have a similar risk of developing hypertension given the same age, initial blood pressure, and body mass index at baseline.     

Diabetic nephropathy. Its relationship to hypertension and means of pharmacological intervention

Hypertension and diabetes mellitus are common chronic conditions which frequently coexist. Diabetic nephropathy is a major cause of elevated blood pressure in patients with insulin-dependent diabetes mellitus (IDDM). Diabetic nephropathy, arterial sclerosis, obesity and association of essential hypertension can be the causes of hypertension in patients with non-insulin-dependent diabetes mellitus (NIDDM). Ambulatory blood pressure monitoring has revealed that the nocturnal fall of blood pressure is blunted in patients with diabetic nephropathy. A blunted diurnal blood pressure variation is seen in microalbuminuric diabetic patients and even in some normoalbuminuric patients. Accumulating data suggest that normalisation of blood pressure in hypertensive IDDM patients is most important to minimise the loss of kidney function. Angiotensin converting enzyme (ACE) inhibitors have been reported to be effective in postponing the development of nephropathy and in slowing its progression. Whether only ACE inhibitors have such beneficial renal effects on diabetic nephropathy is under discussion. While many studies have suggested that insulin resistance and hyperinsulinaemia are related to an elevated blood pressure in hypertensive patients, there does not seem to be enough evidence to prove that insulin per se can raise blood pressure in humans. Neither an insulin infusion within a physiological range nor sustained hyperinsulinaemia and insulin resistance (e.g. patients with insulinoma, cystic ovary syndrome) have been associated with an elevated blood pressure. Insulin resistance in some hypertensive patients may be a consequence of a decreased blood flow due to an increased peripheral resistance. Preliminary evidence suggests that low birth weight or impaired fetal growth is related to hypertension and NIDDM. Familial clustering of diabetic nephropathy suggests the contribution of genetic susceptibility and/or environmental inheritance. The frequent association of nephropathy with hypertension has led to research on the genes related to hypertension (ACE, angiotensinogen). Nevertheless, to date no reliable and clinically useful genetic marker has been found. Attempts to correct the metabolic abnormalities derived from diabetes are a new topic in the treatment of diabetic nephropathy. The effects of HMG CoA reductase inhibitors (antihypercholesterolaemic drugs), aldose reductase inhibitors (inhibitors of the polyol pathway) and glycation inhibitors (inhibitors of formation of advanced glycosylation end-products) on diabetic nephropathy have been evaluated in animal studies and in some clinical trials. Thus far, results with HMG CoA reductase and aldose reductase inhibitors have been somewhat conflicting. The potential therapeutic role of glycation inhibition in the treatment of diabetes deserves further study.     

The hypertensive elder: a review for the primary care provider

Hypertension, the most prevalent cardiovascular disorder in America, affects over 50% of the older adult population. Management of hypertension in the elder is influenced by numerous age-related factors, including physiological changes, co-morbid conditions, functional or cognitive impairments, and polypharmacy issues. As data on the damaging effects of untreated hypertension increase, practice guidelines are increasingly focused on early detection and successful management of blood pressure in the primary care setting. The primary health care provider, having an advanced knowledge base and excellent communication skills, can make effective management of hypertension a reality. This article presents a comprehensive review of assessment, diagnosis, and treatment of hypertension in the older adult. Lifestyle modification and pharmacologic therapy are discussed. Elements of patient education are described, with special emphasis on promoting adherence to a long-term treatment regimen.     

Antihypertensive therapy in stroke: acute therapy, primary and secondary prevention

Arterial hypertension represents the single most important treatable risk factor for stroke, therefore antihypertensive treatment is crucial. Observational studies have shown that in the acute phase of an ischemic stroke blood pressure is elevated during the first few days and helps to restore cerebral perfusion, activates collateral arterial supply and enhances the treatment goal of minimizing infarct size. Especially for acute ischemic strokes with stable deficits drug treatment of hypertension therefore is recommended only at systolic pressures of > or = 220 mm Hg or with diastolic pressures of > or = 120 mm Hg except when heart, lung or renal failure are also present. In primary prevention of stroke there is a large potential for hypertension treatment which reduces the relative risk by 42%. Especially elderly people with moderate hypertension should be treated. One vascular event per year can be avoided in 100 patient treatment years. Only scarce data exist on secondary prevention of stroke which show that hypertension treatment has a major importance for the modification of risk factors.     

Early diagnosis of dementia: neuroimaging

BACKGROUND [corrected] AND PURPOSE: We reviewed Stroke Clinic data to determine the extent of risk factor modification achieved in patients with cerebrovascular disease over 2 years. METHODS: Visits to the Stroke Clinic of a tertiary medical center from July 1, 1994, through June 30, 1996, were reviewed. Obesity, smoking, hypertension, hyperlipidemia, hyperglycemia, and lifestyle changes were noted in patients with >/=2 visits (n=61) and measures (number varied) of these parameters. RESULTS: Fifty-six patients (92%) had primary care physicians. In the 49 patients with >/=2 weight measurements, 33 (67%) were moderately or severely overweight by weight-height correlation. Forty-four patients (90%) remained in the same weight category. Of the 60 patients with available blood pressure data, 50 (83%) were hypertensive. At their last visits, 43 of the 50 (86%) were receiving medications, and 22 of the 43 treated (51%) were controlled. Serum glucose remained elevated in 14 of 47 patients (30%) and in 11 of 16 diabetic patients (69%). Thirty-six of 47 patients (55%) had elevated lipid measurements. None of the 21 smokers quit during the study period. Few patients modified dietary and exercise practices. Of 61 patients, 29 (48%) sustained vascular events during the study, with 17 of these 29 patients (59%) having strokes or transient ischemic attacks. CONCLUSIONS: Although most patients were asked to quit smoking, received advice regarding diet and exercise, and were medicated for hypertension, elevated glucose, and cholesterol levels, their risk factor profiles showed little improvement during the 2-year period. More effective methods of controlling stroke risk factors are needed.     

Hypertension in the acute phase of cerebral infarction; not always to be treated

Hypertension is observed in three-fourths of the patients in the acute phase of a cerebral infarction. Treatment of an elevated blood pressure in the acute phase of a cerebral infarction is discouraged for the following arguments: In most instances the elevated blood pressure decreases spontaneously in the first few days after the infarction and stabilisation of the blood pressure is usually seen within 4 to 7 days. The elevated blood pressure in the acute phase of the cerebral infarction may be considered a favourable adaptation mechanism aimed at maintaining cerebral perfusion in the region surrounding the infarction. As a consequence lowering of the elevated blood pressure may be harmful because it can lead to expansion of the infarction. No controlled prospective studies to determine if treatment of hypertension in the acute phase of a cerebral infarction might be of benefit have been performed. There are, however, several case reports showing that treatment of an elevated blood pressure in the acute phase of a cerebral infarction is associated with dramatic progression of the neurological deficit. Exceptions can be made for situations where diastolic blood is repeatedly higher than 130-140 mmHg or where there are concomitant cardiovascular diseases, such as myocardial infarction, heart failure or a dissecting aneurysm requiring immediate antihypertensive treatment.     

Nocturnal blood pressure and relation to vasoactive hormones and renal function in hypertension and chronic renal failure

The purpose of this study was to assess the blood pressure profile and to measure vasoactive hormones in patients with essential hypertension (n=61), secondary hypertension (n=32) and chronic renal failure (n=32) matched with healthy control subjects (n=35), and to study the relationship between circadian changes in blood pressure and baseline levels of vasoactive hormones and renal function. Non-invasive, automatic blood pressure measurement was performed for 24 or 48 h. Venous plasma concentrations of renin, angiotensin II, aldosterone, arginine vasopressin, atrial natriuretic peptide and endothelin were measured. The mean 24-h blood pressure was higher in all groups of hypertensive patients than in control subjects. The nocturnal blood pressure fall was preserved in essential hypertension, in contrast to secondary hypertension in which it was attenuated. In the patients with chronic renal failure the 24-h mean blood pressure was the same as in the controls. Night-time blood pressure was higher among the chronic renal failure patients than in the control group, and the nightly blood pressure fall in both diastolic and systolic blood pressure was reduced. Plasma concentrations of renin activity, arginine vasopressin, atrial natriuretic peptide, aldosterone and endothelin were significantly increased in secondary hypertension and chronic renal failure, compared to essential hypertension and control subjects. Plasma angiotensin II was increased in chronic renal failure compared to essential hypertension and controls. Estimated creatinine clearance and nightly blood pressure dips were inversely correlated in essential and secondary hypertension, i.e. with a decreasing renal function both systolic and diastolic nightly blood pressure dips were gradually attenuated. In the whole group of patients the nightly systolic and diastolic blood pressure dips were negatively correlated to basal plasma renin activity, plasma aldosterone and atrial natriuretic peptide levels, i.e. the higher the basal plasma hormone level the lower the blood pressure dip. In conclusion, patients with essential hypertension have elevated but normally configured 24-h blood pressure profiles, and patients with different kinds of secondary hypertension have elevated 24-h blood pressure profiles and attenuated nightly systolic and diastolic blood pressure falls. The more the renal function is reduced and the more the plasma levels of renin and aldosterone are increased, the more the nocturnal fall in blood pressure is reduced. It is suggested that the attenuated or absent decrease in nocturnal blood pressure in secondary renal hypertension is caused by an abnormally increased secretion of vasoactive hormones and/or by so far unknown factors released from the diseased kidney.     

Inhibition of plasma endothelin-1 concentration by captopril in patients with essential hypertension

The aim of this study was to determine whether captopril has any effect on plasma endothelin-1 (ET-1) concentration in patients with essential hypertension. Nine normotensives and eleven hypertensives were included in this study. Blood pressure and pulse rate were monitored before and at 60 min after captopril ingestion (25 mg). Simultaneously, blood samples for plasma ET-1 and plasma renin activity (PRA) determination were obtained. In the normotensives, captopril treatment resulted in a significant rise in PRA, but without statistical changes in blood pressure and plasma ET-1. By contrast, in the hypertensives, although PRA elevated similarly after captopril, both blood pressure and plasma ET-1 decreased significantly compared with their respective preloading level. These data suggest that the blood pressure-lowering effect of captopril in essential hypertension may be at least in part, mediated by its inhibition of ET-1 production from the vascular endothelium.     

Lifestyle modifications for diabetes management

Nutrition therapy and physical activity can assist persons with diabetes to achieve metabolic goals. Several lifestyle strategies can be used. Monitoring metabolic parameters, including blood glucose, glycated hemoglobin, lipids, blood pressure, and body weight, as well as assessing for quality of life are essential to determine whether treatment goals are being achieved by lifestyle changes. If not, adjustments in the overall management plan need to be made.     

Effect of intensified red blood cell aggregability on arterial pressure and mesenteric microcirculation

Intensified aggregability of red blood cells (RBC) was produced in adult white rats by the step-by-step intravascular administration of a high-molecular-weight dextran, with a molecular weight approximating that of blood fibrinogen. As a result, the systemic arterial pressure was elevated by more than one-third of the initial level, whereas the diameter of arterioles in the intestinal mesentery remained practically unchanged. This provided sufficient grounds for the conclusion that the increase in the total peripheral resistance was due to disturbances in blood rheological properties. Despite the elevated arterial pressure, the blood flow velocity in mesenteric arterioles displayed a clear-cut tendency to slow down. Simultaneously, a large number of RBC aggregates appeared in the mesenteric microvessels. In patients with a stable form of arterial hypertension the RBC aggregability index was found to be significantly increased as compared with that of the healthy control group. Following treatment with Ca(2+)- and beta-adrenergic blockers the index decreased significantly in parallel with the lowering of arterial pressure. The obtained results suggest that the intensified RBC aggregation in microvessels causing a disturbance of normal blood flow structure, and hence of blood rheological properties, might be an important factor responsible for the elevation of systemic arterial pressure in humans with arterial hypertension.     

Centralized i.v. team provides inpatient and home-care treatment

AIM: The study of the effects of the inhibitor of angiotensin converting enzyme ramipril (tritace) on the 24-h profile of blood pressure (BP) in patients with mild and moderate arterial hypertension. MATERIALS AND METHODS: Ramipril was given to 21 males aged 45-68 years with essential hypertension stage II (WHO criteria) with stable elevated diastolic blood pressure (95-114 mm Hg) in a single dose 2.5-10 mg/day. Captopril controls received 100 mg twice a day. BP was monitored using "SpaceLabs Medical" unit (model 90207, USA). RESULTS: Compared to placebo, ramipril lowered systolic and diastolic blood pressure both for the 24-h period and in the day time; captopril lowered only diastolic BP in the day time. Side effects of long-term application of ramipril occurred 2 times less frequently than in application of captopril. CONCLUSION: Long-term treatment with ramipril in the above regimen provides more effective control of BP than captopril in the above doses in patients with mild and moderate hypertension.     

Continuous haptic information in target tracking from a moving platform

The Dietary Approaches to Stop Hypertension (DASH) study was a National Heart, Lung, and Blood Institute multicenter trial that compared the impact of three dietary patterns on blood pressure (BP) among adults with high normal blood pressure or mild (Stage I) hypertension. DASH's high minority representation (two-thirds of the 459 randomized participants came from minority populations, and 60% of the cohort were African American) offered a valuable opportunity to assess factors affecting minority enrollment and retention in clinical trials of lifestyle modification. Recruitment strategies included targeted mailings to specific groups, mass mailings, community and worksite screenings, and mass media advertising; the four DASH clinical centers also reimbursed participants from $150 to $160. The most productive recruitment strategies tended to be mass mailings directed at a broad audience that was weighted toward, but not limited to, minority participants. DASH's African-American participants overwhelmingly (89%) cited health and dietary factors, such as learning more about blood pressure and healthy eating habits, as their primary reason for participating, while only six percent listed the financial incentives as their primary reason for participating. Eighty-eight percent of African-American respondents reported they would participate again in a similar study. The insights from DASH should help inform future efforts to recruit minority participants.     

Hypertension in insulin-dependent diabetes

Hypertension is seen in approximately 85% of IDDM patients with diabetic nephropathy and blood pressure elevation is an early event in the development of this complication. In IDDM patients with clinical nephropathy, a positive correlation has been demonstrated between the blood pressure and the urinary albumin excretion and reduction of blood pressure reduces albuminuria as well as the rate of decline in glomerular filtration rate. Also extrarenal abnormalities such as retinopathy, cardiovascular diseases and signs of endothelial dysfunction, sometimes seen in non-diabetics with severe and/or prolonged hypertension, are frequently demonstrated in IDDM patients with clinical nephropathy. The aim of the present study was to provide circumstantial evidence for the thesis that hypertension in IDDM patients with nephropathy is secondary to the kidney involvement and not the cause of the kidney disease. Furthermore, by familial and physiological studies the review also aimed to contribute to the understanding of the pathogenesis of hypertension in patients with clinical nephropathy. Finally the question of optimal pharmacological antihypertensive treatment was discussed. It was demonstrated that in IDDM patients with elevated urinary albumin excretion above normal level the prevalence of hypertension is 60%, whereas in patients without signs of renal impairment hypertension is not more prevalent as in the age and sex-matched background population (about 4% in both groups). Based upon the observation, that some of these IDDM patients with hypertension but normal UAE were hypertensive for many years, we designated this group as IDDM patients with essential hypertension for further studies. In this group, we had the opportunity to study the association between blood pressure and the development of extrarenal complications in patients with IDDM. The group with essential hypertension and IDDM showed to have less retinopathy compared with diabetics with similar blood pressure but elevated UAE. In contrast to the hypertensive patients with nephropathy, a normal transcapillary escape rate of albumin and normal plasma levels of von Willebrand factor, of angiotensin-converting-enzyme and of inactive renin were demonstrated in the former group of patients. Thus, the extrarenal abnormalities found in IDDM patients with hypertension are more closely associated to the presence of albuminuria than to the elevation of blood pressure, indirectly supporting the hypothesis that hypertension per se is not the cause of these abnormalities in the IDDM patients with nephropathy. Furthermore, the present study does not disclose a genetic disposition to hypertension in IDDM patients with elevated UAE.     

Risk for hypertension and pain sensitivity in adolescent boys.

Reduced pain perception has been observed in many studies of spontaneously hypertensive rats and human hypertensive patients. To determine whether a reduced sensitivity to pain could be observed in a group of clearly normotensive individuals who may be at risk for hypertension, a mild to moderate pain stimulus was administered to 177 14-year-old boys. Boys with a normatively elevated resting systolic blood pressure tolerated mechanical finger pressure significantly longer than boys with lower blood pressure. As well, boys with both normatively elevated resting systolic blood pressure and a parental history of hypertension reported significantly less pain during finger pressure than lower risk participants. These findings could not be explained by personality factors and suggest that hypertension-related hypoalgesia is associated with processes involved in the development of the disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Calcific tendinitis of the pectoralis major insertion. A report of two cases

The authors described developmental anomaly of the right kidney associated with hypertension and pyonephrosis in a 37 years old male. The authors reported the diagnostic problems in this kind of hypertension. After nephrectomy had been performed the elevated blood pressure returned to normal values without any additional pharmacological treatment.     

Drug management of hypertensive disorders of pregnancy

Drugs used in the acute and long-term management of hypertension in pregnancy and the preeclampsia-eclampsia syndrome have been reviewed and their therapeutic effects and maternal and fetal adverse effects have been considered. The review also focuses on recent developments in the areas of prevention and management of pre-eclampsia-eclampsia syndrome. Although a number of new drugs have emerged, as potentially useful in the management of hypertension in pregnancy and pre-eclampsia-eclampsia syndrome, some remain at the cornerstone of therapy; for example, methyldopa for long-term treatment of chronic hypertension, hydralazine or nifedipine for rapid reduction of severely elevated blood pressure, and magnesium sulphate for eclampsia. Some of these agents, especially the calcium antagonists, show promise in that their use is associated with fewer side effects. Safety for the fetus, however, has not been adequately evaluated yet. Neither aspirin nor calcium supplements appear to improve the outcome in pregnancy. Currently, the dilemma whether to treat hypertension in pregnancy and pre-eclampsia-eclampsia syndrome with old, established, cost-effective drugs or the promising newer drugs provides an interesting academic challenge.     

Malignant hypertension in a patient with primary aldosteronism with elevated active renin concentration

A 40-year-old male, with a past history of hypertension but receiving no medical treatment, was referred. He manifested malignant hypertension (190/130 mmHg; Keith-Wagener III), renal dysfunction (serum creatinine, 3.8 mg/dl), and elevated plasma aldosterone (450 pg/ml) and active renin concentration (ARC, 104 pg/ml). His blood pressure was controlled with multiple antihypertensive agents and ARC thus decreased (4.3 pg/ml), but aldosterone remained elevated. Abdominal magnetic resonance imaging (MRI) revealed a right adrenal adenoma, and aldosterone-producing adenoma was confirmed by adrenal venous sampling. Primary aldosteronism very rarely develops to malignant hypertension, and even in that case ARC is suppressed. Therefore this is a rare case of primary aldosteronism complicated with malignant hypertension and high ARC.     

A collaborative audit of the management of hypertension in general practice

We carried out an audit of the management of essential hypertension in general practice, against standards based on current guidelines. We examined the records of 882 hypertensive subjects (on medication) in whom hypertension had been diagnosed between January 1989 and December 1993, from 14 general practices in the Portsmouth and South East Hampshire Health Authority. The overall prevalence of hypertension was 3.5%. Pretreatment blood pressure had been measured on three or more occasions in 87% of patients. Pretreatment blood pressure was equal to or greater than 150/95 mmHg in 96% and 160/100 mmHg in 86.5% of patients. A thiazide diuretic was the initial drug of choice in 30% of patients, with beta-blockers being the most popular initial treatment. Ninety per cent of patients had had their blood pressure measured at least once during the preceding year. In 82.5% of patients, current blood pressure was less than 150/95 mmHg, while 44% achieved a current blood pressure less than 140/90 mmHg. We conclude that the prevalence of hypertension in this population was lower than expected, suggesting the need for improved screening. We also propose that the initial treatment choice should be a thiazide in the majority, which would result in significant cost saving. The blood pressure control was suboptimal compared to current guidelines.     

Hypertension and the obstetrician-gynecologist

Hypertension is a major risk factor for cardiovascular-related morbidity and death. Antihypertensive therapy markedly reduces the risk caused by elevated blood pressure. Earlier treatment of hypertensive patients should reduce deaths and morbidity even further. The obstetrician-gynecologist has the opportunity and responsibility to identify hypertensive patients early in the course of their disease. He must also confront the problem of elevated blood pressure associated with the use of oral contraceptives. In addition to its impact on the general population, chronic hypertension presents special problems during pregnancy. Pregnant women with elevated blood pressure have an increased fetal mortality rate and develop pre-eclampsia more frequently and earlier than nonhypertensive women. Antihypertensive treatment possibly increases fetal survival; when used appropriately, it definitely does not decrease fetal salvage. The appropriate use of antihypertensive therapy during pregnancy requires an understanding of the mechanism of action of these agents and recognition of side effects, especially those important during pregnancy.