Biomedical subjects

I Os

Publications and source records attributed to I Os.

At least 19 recordsLinked to original sources

PubMed1999

[An overview of hypertension studies with calcium antagonists].

Calcium antagonists are widely used in the treatment of hypertension. However, few endpoint studies with calcium antagonists have been done to prove reduction in hypertensive complications. Results of the STONE, SYST-EUR and SYST-CHINA studies show that long-acting calcium antagonists are effective compared to placebo, especially in patients with isolated systolic hypertension and diabetes. Ongoing prospective and randomized trials like STOP II, INSIGHT, NORDIL, ALLHAT and ASCOT will clarify whether calcium antagonists are more effective than well-proven diuretics and betablockers. ASCOT will test the hypothesis that amlodipine is more efficacious than atenolol in preventing cardiac complications in 18,000 hypertensive patients with high coronary risk including diabetes (among them, 2,000 in Norway). The study is also randomizing the patients in a factorial design to either atorvastatin or placebo, testing the so-called lipid hypothesis.

Antihypertensive Agents↗

PubMed1999

Effects of doxazosin in the gastrointestinal therapeutic system formulation versus doxazosin standard and placebo in mild-to-moderate hypertension. Doxazosin Investigators' Study Group.

The alpha 1-blocker doxazosin is a well-established therapy for hypertension and benign prostatic hyperplasia; however, in its standard form, a multiple-step titration regimen is usually required. The new gastrointestinal therapeutic system (GITS) formulation of doxazosin greatly minimizes the need for titration by changing drug-delivery rate and the pharmaco-kinetic profile. To demonstrate this in hypertensive patients, we assessed the effects of doxazosin GITS 4 or 8 mg once daily versus doxazosin standard 1-8 mg once daily, and placebo, in an integrated analysis of two multicenter, double-blind, randomized, parallel-group trials. Each trial included a 2-week washout period and 12 weeks of therapy. One study compared doxazosin GITS, doxazosin standard, and placebo in 392 patients with mild hypertension [blood pressure (BP) 95-105/ < or = 180 mm Hg]; the other study compared doxazosin GITS with doxazosin standard in 315 patients with mild-to-moderate hypertension (BP 95-115/ < or = 220 mm Hg). The primary outcome measure was the proportion of responders (sitting diastolic BP < 90 mm Hg or 10-mm Hg decrease from baseline 24 h after the dose) at the final visit for the per-protocol population. Mean baseline BP and heart rate were well matched in each group. Approximately 64% of patients with doxazosin GITS (198 of 309 patients) and 68% with doxazosin standard (207 of 304 patients) achieved goal BP response at the final visit versus 36% with placebo (25 of 70 patients; p < 0.05). The majority with doxazosin GITS (60%) remained at the initial 4-mg starting dose. Doxazosin GITS was as effective as doxazosin standard, and both were more effective than placebo in controlling BP in mild-to-moderate hypertension. Doxazosin GITS was well tolerated, and fewer patients with the GITS formulation discontinued therapy because of side effects compared with doxazosin standard or placebo. Syncope was not reported with doxazosin GITS. Whereas the efficacy of doxazosin GITS at 4 or 8 mg is equivalent to that of the standard regimen in this combined analysis, the GITS formulation appears to eliminate the need for titration in most patients.

Adult↗

PubMed1998

[Pregnancy, essential hypertension and chronic renal disease].

Women with chronic hypertension or renal disease are at a particular high risk of developing pre-eclampsia or eclampsia. Pre-eclampsia is associated with an increased risk of fetomaternal complications. In women with uncomplicated mild and moderate hypertension, pregnancy is usually normal. Treatment of high blood pressure aims at reducing maternal cardio- and cerebrovascular catastrophies, and the benefit of the treatment must be weighed against possible harmful effects on the foetus. In some cases, antihypertensive treatment can be discontinued, or medication changed. Preconceptional counselling is important both for women with chronic hypertension and, even more so, for women with renal disease, since the outcome of the pregnancy may be affected by the underlying disease.

Female↗

PubMed1998

Evidence of excess hereditary predisposition in women with angiographically documented coronary artery disease.

In a hospital-based case-control study including women and men with angiographically documented coronary artery disease (CAD) admitted to a university hospital during a 6-month period, we observed an excessive hereditary predisposition in women. Clustering of risk factors was more pronounced in women than in men. Thus, the results suggest that hereditary factors as well as multiple risk factors are essential when CAD is expressed in women.

Angiography↗

PubMed1997

Comparison of the combination of enalapril and a very low dose of hydrochlorothiazide with atenolol in patients with mild-to-moderate hypertension. Scandinavian Study Group.

The blood pressure lowering effect and tolerability of the angiotensin-converting enzyme inhibitor enalapril combined with a very low dose of hydrochlorothiazide (HCTZ) were compared with the selective betareceptor blocker atenolol in patients with mild-to-moderate hypertension. Three hundred seventy-four patients were randomized into a triple-blind, parallel, active-controlled 12-week study period comparing enalapril/HCTZ (20/6 mg) with atenolol (50 mg) after a 4-week placebo baseline period. Blood pressure (BP), clinical and laboratory safety, and metabolic laboratory variables were assessed. Enalapril/HCTZ as well as atenolol reduced both sitting and standing diastolic and systolic BP (P < .001), but enalapril/HCTZ had a more pronounced effect than atenolol on sitting systolic BP (P = .019); there was a trend toward more patients achieving target diastolic BP (<90 mm Hg, P = .053). No clinically important differences in safety and tolerability were observed.

Adolescent↗

PubMed1997

Alpha-1-antitrypsin deficiency associated with hepatic cirrhosis and IgA nephritis.

The association between alpha1-antitrypsin (A1AT) deficiency and glomerulonephritis has only sporadically been reported, and mostly based upon autopsy findings, as opposed to the more frequent linkage between A1AT deficiency and lung emphysema with or without hepatic cirrhosis. The present case report describes a 30-year-old man with A1AT deficiency, without evidence of lung disease, who developed hepatic cirrhosis in early childhood and IgA glomerulonephritis and hypertension in adult life. The IgA nephritis followed an unusual course, with a sudden deterioration of the renal function, possibly induced by uncontrolled hypertension or the possible occurrence of vasculitis. After 6 months of hemodialysis, the patient successfully underwent living-related-donor kidney transplantation.

Adult↗

PubMed1995

[How to combine antihypertensive drugs?].

Many hypertensive patients do not respond adequately to single-drug therapy and may therefore require two or more drugs to reach the treatment goal. The drugs used in combination therapy should have additive or synergistic effects on blood pressure. A potential benefit of combinations is to use lower doses of each drug, which may attenuate or abolish the occurrence of side effects. Different combinations are discussed, as well as the inhibition of compensatory mechanisms that may otherwise counteract the antihypertensive effect.

Antihypertensive Agents↗

PubMed1995

[Alpha 1-antitrypsin deficiency--not only pulmonary and hepatic involvement].

The association between deficiency of alpha-1-antitrypsin (A1AT) and glomerulonephritis has been only sporadically reported on, as opposed to the linkage between A1AT-deficiency and lung emphysema or hepatic cirrhosis. We describe the case of a 30-year-old man with A1AT deficiency who developed hepatic cirrhosis in early childhood, and IgA glomerulonephritis and hypertension in adult life. The IgA nephritis followed an unusual course. After three years of slight elevation of serum creatinine levels, the patient rapidly developed renal failure necessitating acute hemodialysis. The deterioration of the renal function was preceded by eruption of skin lesions, believed to represent a vasculitis. After six months of hemodialysis, the patient successfully received a transplanted kidney from his mother. The literature is reviewed with respect to the association between A1AT-deficiency and renal disease. We discuss possible underlying causes for the rapid deterioration of renal function in this patient.

Adult↗

PubMed1995

[Refractory hypertension].

Resistant hypertension is a common disorder in general practice, and poses a challenge to clinicians. It is generally defined as failure to reduce blood pressure adequately despite the use of at least three different antihypertensive agents with different modes of action. The importance of recognizing expansion of plasma volume as a mediator of resistance to therapy is emphasized. Some patients may have white-coat hypertension. An even larger group of patients may fail to comply with the prescribed medication. A good physician-patient relationship is vital, and education of the patient is crucial for obtaining better adherence to the medication.

Antihypertensive Agents↗

PubMed1995

Mental stress increases glucose uptake during hyperinsulinemia: associations with sympathetic and cardiovascular responsiveness.

Infusion of epinephrine and norepinephrine reduces insulin-mediated glucose disposal, ie, induces insulin resistance. Mental stress increases concentrations of both plasma catecholamines. However, the effect of acute mental stress on insulin-mediated glucose uptake has not been examined. We observed in pilot studies that a mental stress test (MST) during a euglycemic glucose clamp decreased blood glucose concentration. In a prospective study, euglycemic hyperinsulinemia was established during 120 minutes of glucose clamping; the subjects (N = 74) then underwent 5 minutes of intense mental arithmetics with infusion rates of glucose and insulin kept constant. During MST, plasma epinephrine and norepinephrine increased (by 0.23 +/- 0.02 and 0.50 +/- 0.05 nmol/L) together with blood pressure ([BP] by 18 +/- 8/9 +/- 1 mm Hg) and heart rate ([HR] by 21 +/- 1 beats per minute), with P less than .0001 for all changes. During mental stress, blood glucose concentration decreased by 0.4 +/- 0.1 mmol/L (P < .0001), followed by full recovery after another 10 minutes. Serum insulin was unchanged, indicating an acute but transient increase in glucose uptake. This finding was unrelated to age, sex, body mass, and BP status. Fifty-nine subjects with a decrease in glucose concentrations during MST were characterized by accentuated epinephrine response to MST (a change of 0.25 +/- 0.03 v 0.12 +/- 0.02 nmol/L, P = .001), increase in systolic BP (by 20 +/- 2 v 10 +/- 3 mm Hg, P = .008), and increase in HR (by 23 +/- 2 v 15 +/- 2 beats per minute, P = .008) as compared with 15 subjects with unchanged/increased glucose concentration.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1995

Relationship between hemorheological factors and insulin sensitivity in normotensive and hypertensive premenopausal women.

The present study aimed at testing a possible relationship between hemorheologic factors such as hematocrit and whole blood viscosity, and insulin sensitivity in premenopausal, hypertensive (HT), and normotensive (NT) women. Fourteen HT and 12 NT women were studied with the hyperinsulinemic euglycemic glucose clamp technique. Insulin sensitivity was similar in NT and HT (8.7 +/- 0.8 v 7.6 +/- 0.8 arbitrary units). Whole blood viscosity did not differ between the two groups at any shear rate (shear rate 5.2 sec-1: 7.5 +/- 0.4 in NT and 8.0 +/- 0.3 in HT, P = NS). Statistically significant negative correlations were observed between the insulin sensitivity index and calculated whole blood viscosity at both high (r = -0.49, P < .01) and low shear rates (r = -0.50, P < .01, n = 26). Insulin sensitivity index was also negatively correlated to body mass index in the combined groups (r = -0.40, P = .04), and to both systolic and diastolic blood pressure (r = -0.44, P = .02 and r = -0.38, P = .05, respectively). In multiple regression analysis, whole blood viscosity, body mass index, systolic, and diastolic blood pressure accounted for 39% of the variation in insulin sensitivity index, but only whole blood viscosity was an independent explanatory variable for the insulin sensitivity index. These results suggest hemorheologic, and therefore indirectly hemodynamic factors as correlates to insulin sensitivity.

Blood Glucose↗

PubMed1995

The efficacy and tolerability of enalapril in a formulation with a very low dose of hydrochlorothiazide in hypertensive patients resistent to enalapril monotherapy.

The antihypertensive efficacy and tolerability of formulations of enalapril and low (12.5 mg) and very low (6 mg) doses of hydrochlorothiazide (HCTZ) were compared with enalapril and placebo. Four hundred and two patients with mild to moderate essential hypertension were treated with 20 mg enalapril for 8 weeks. Patients (n = 296) with persistent supine diastolic blood pressure > 95 mm Hg after enalapril monotherapy were randomized to receive enalapril/placebo (group I), 6 mg enalapril/HCTZ (group II), or 12.5 mg enalapril/HCTZ (group III) for another 8 weeks in a double-blind design. The mean reductions in blood pressure were significantly larger in groups II and III compared to group I, 7.3 (95% CI, -9.0; -6.2), 7.7 (-9.2;-6.3), and 4.1 (-5.9;-2.9) mm Hg, respectively P < .01 for groups II and III compared to group I). No difference in side effects was observed between the three groups. A very low dose of 6 mg HCTZ acts synergistically when given together with enalapril, but is devoid of adverse metabolic effects.

Adolescent↗

PubMed1995

Effect of dietary counselling on blood pressure and arterial plasma catecholamines in primary hypertension.

There is still a need of support for nonpharmacologic treatment of uncomplicated, mild-to-moderate essential hypertension. We investigated whether a low sodium-based diet implemented by a nutritionist could lower blood pressure and affect sympathetic activity. Middle-aged, otherwise healthy men with never-treated essential hypertension (n = 95) were randomized to an intervention group, a blood pressure control group, and a time control group. The intervention group was advised to use less sodium chloride in their diet, and if necessary, less saturated fat and decrease body weight. They attended regular clinic visits as did the blood pressure control group. After 1 year, the intervention group had achieved on average 72 mmol/24 h lower urinary sodium excretion (P < .001) and a decrease in body weight of 2.7 +/- 0.5 kg (P < .001). Both supine and standing mean blood pressure were on average 8 to 10 mm Hg lower after intervention compared with the two control groups (P < .001). Arterial plasma epinephrine, measured in all 40-year-old subjects (n = 30), decreased in parallel in all three groups (P < .05), indicating some habituation to the invasive procedure and clinic visits. However, the decrease in norepinephrine was significant (P < .001) only in the intervention group; it correlated with the weight loss (r = 0.76, P < .05) and was significantly higher (P < .05) than in both control groups. These results suggest that broad dietary advice (ie, low intake of sodium chloride, saturated fat and energy), implemented by a nutritionist, may have a significant blood pressure lowering effect and a favorable sympathicolytic effect in uncomplicated, mild-to-moderate essential hypertension.

Adult↗

PubMed1995

Hypertension therapy and risk of coronary heart disease: how do antihypertensives affect metabolic factors?

A recent meta-analysis of hypertension treatment trials demonstrated a marked reduction in the incidence of cerebrovascular disease, but a less pronounced reduction in coronary heart disease. Treatment consisted mainly of diuretics and beta-blockers, and this paper discusses the possible influences of their metabolic side effects on coronary risk factors compared with newer agents: angiotensin-converting enzyme (ACE) inhibitors, selective alpha 1-adrenoceptor inhibitors and calcium channel blockers. Several studies are underway to compare the effect of these compounds with diuretics and beta-blockers with respect to long-term cardiovascular morbidity and mortality. Until the results of these studies are available, young patients (i.e. < 60-65 years) at high risk of coronary heart disease, especially patients with the insulin resistance syndrome or diabetes mellitus, should in our opinion be treated with ACE-inhibitors, selective alpha 1-adrenoceptor inhibitors or calcium channel blockers.

Antihypertensive Agents↗

PubMed1995

A double-blind study of psychosocial factors in 40-year-old women with essential hypertension.

Most studies on essential hypertension have been performed in men. The aim of the present study was to describe psychosocial characteristics of 40-year-old women with never-treated essential hypertension. Psychosocial factors like childhood traumas, economy and education were studied, and psychological assessments of irritability, hostility, 'John Henryism' and type A behavior pattern carried out. Hypertensive premenopausal women (n = 29) were compared with healthy, age-matched, normotensive women (n = 18). Neither the women nor the examining physicians were aware of the subjects' blood pressure status, and the setting, thus, was double-blind. All women were investigated in the same phase of the menstrual cycle, and in a random order. The hypertensives' parents more often had hypotension than the normotensives'. The psychiatrist who conducted the interviews correctly classified the majority of subjects as either hypertensive or normotensive. Alexithymia and difficulties in coping with aggression were more prevalent among the hypertensives. Hypertensive and normotensive women did not differ in most of the psychosocial factors previously found to differ between hypertensive and normotensive men. Our data may imply that psychosocial as well as genetic factors may contribute differently to the etiology of essential hypertension in women than in men.

Adaptation, Psychological↗

PubMed1995

Insulin resistance and sympathetic nervous system activity in hypertensive and normotensive premenopausal women.

The aim of the present study was to compare insulin sensitivity and catecholamine responses to insulin in lean, hypertensive (HT) and normotensive (NT) premenopausal women. HT (BP 149 5/99 +/- 2 mmHg, n = 14) and NT (BP 128 +/- 4/81 +/- 2 mmHg, n = 12) were matched for age (46 +/- 1 vs. 47 +/- 1 years) and body mass index. Insulin sensitivity was determined by fasting serum insulin, glucose disposal rate (GDR) and insulin sensitivity index (GDR/I) using euglycemic hyperinsulinemic glucose clamp technique. Sympathetic nervous system activity was assessed by plasma adrenaline and noradrenaline in arterialized venous blood at baseline and during euglycemic hyperinsulinemic glucose clamp. Insulin sensitivity index correlated negatively with total cholesterol in HT (r = -0.57, p < 0.05) and with body mass index (r = -0.42, p < 0.05, n = 26). The response in catecholamines to euglycemic hyperinsulinemia in HT differed from NT with an increase both in noradrenaline and adrenaline. Blood pressure and heart rate responses, however, did not differ between HT and NT. Fasting serum glucose did not differ between the two groups (4.7 +/- 0.1 mmol/l in HT vs. 4.9 +/- 0.1 mmol/l in NT), nor did fasting serum insulin (16 2 mU/l vs. 13 mU/l). Glucose disposal rate (8.8 +/- 0.5 vs. 8.7 +/- 0.7 mg kg-1 body weight min-1) and insulin sensitivity index were similar (7.3 +/- 0.8 vs. 7.6 +/- 0.8 arbitrary units). We conclude that in lean, premenopausal hypertensive women insulin sensitivity is not reduced compared with age- and weight-matched normotensive women, but the hypertensives respond to hyperinsulinemia with increased plasma catecholamines, i.e. sympathetic nervous systemic activity. Also, insulin sensitivity correlates negatively with serum cholesterol. Thus, an insulin-hyperadrenergic interaction may possibly be involved as a pathogenetic factor in lean hypertensive women.

Analysis of Variance↗

PubMed1995

Non-responders.

Non-responders are frequently encountered in clinical practice, and different strategies have to be considered as well as diagnostic approaches. Nearly 50% of all hypertensive patients will require more than one drug to control blood pressure. The complexity of high blood pressure is reflected in the different responses to antihypertensive agents with varied mode of action. White coat hypertension may coexist with sustained hypertension and complicate interpretations of blood pressure measurements. Noncompliance is a challenge for the doctor, and may be difficult to solve. It depends not only on the patient-doctor relationship, but also on the patient's perception of own health and the side effect profile of the drugs. Patient education is crucial. Secondary hypertension should be excluded in truly resistant hypertension. Volume overload is frequent in essential hypertension, and volume expansion follows an excessive dietary sodium intake. These and other possibilities should be sought for when explaining failure to respond to antihypertensive therapy.

Antihypertensive Agents↗

PubMed1995

Risk factors and differential antihypertensive therapies.

A less pronounced reduction in the incidence of coronary heart disease than in cerebrovascular events has been observed during antihypertensive therapy. Hypertension may not be the dominant risk factor for coronary heart disease as it is for cerebrovascular disease, and metabolic factors gain more importance. The reason for the differential effect of antihypertensive therapy could partly be explained by the adverse metabolic effects of some antihypertensive drugs which may thus attenuate the beneficial effects. When decision is made concerning antihypertensive treatment, it is imperative to assess the overall cardiovascular risk of the patient and take into account the possible impact on these factors of the different antihypertensive drugs.

Antihypertensive Agents↗