The influence of monotherapy with oxprenolol and nitrendipine on ambulatory blood pressure in hypertensives

We investigated whether beta-blockers or calcium-antagonists might be preferred in baseline antihypertensive therapy. In middle-aged male patients with essential BP readings did not differ between patients on Oxprenolol or on Nitrendipine (average BP: 123 +/- 12/81 +/- 14 vs. 129 +/- 17/80 +/- 10 mmHg), when clinical casual BP was within the normotensive range. Average BP at work was lower than clinical casual BP taken at the same day (125 +/- 14/80 +/- 12 vs. 133 +/- 12/87 +/-13 mmHg). A linear dependency between SBP at work and level of self reported physical activity (F(3,413) = 7.6; p less than or equal to 0.001) and arousal was found (F(3,374) = 5.2; p less than or equal to 0.02). Patients on Oxprenolol consistently had lower SBP at a particular level of physical activity and at lower levels of arousal than patients on Nitrendipine. We conclude that both regimen were equally effective as baseline antihypertensive monotherapy.

Exercise and resting blood pressure and heart rate changes 24 h after dosing in patients with essential hypertension receiving 16/260 oxprenolol Oros once daily

Nineteen patients receiving oxprenolol slow-release (SR) 160 mg (three patients) or 320 mg (16 patients) once daily for mild to moderate hypertension were treated with oxprenolol Oros 16/260 once daily for 3 weeks following a 2 week placebo wash-out period. Repeated dosing with both Oros and SR oxprenolol preparations, in comparison with placebo, significantly reduced supine systolic and diastolic blood pressures, and pulse rate at 24 h after dosing. Single Oros doses also significantly reduced pulse rate and diastolic, but not systolic, blood pressure at 24 h. The reduction in supine systolic blood pressure was greater during repeated dosing with oxprenolol SR than after a single dose of the Oros preparation. Control of supine diastolic blood pressure (less than or equal to 90 mm Hg) at 24 h after dosing was achieved in 13 out of 18 patients with oxprenolol SR (two out of three patients given 160 mg, and 11 out of 15 given 320 mg). Similar control was achieved in 11 out of 18 patients after a single dose of oxprenolol Oros, and in 13 out of 17 patients treated for 3 weeks. The mean percentage reduction in exercise heart rate (EHR) compared to placebo, at 24 h after dosing, was 16% following Oros treatment for 3 weeks, and 12% following SR administration. After a single dose of oxprenolol Oros EHR, was reduced by 9% at 24 h compared to placebo. At 3 weeks the Oros formulation was significantly better than the SR tablet at reducing EHR. Oxprenolol Oros 16/260 was effective over 24 h and well tolerated.(ABSTRACT TRUNCATED AT 250 WORDS)

Serial measurements of systolic time intervals during treatment with hydrochlorothiazide alone and combined with other antihypertensive agents

As part of the Veterans Administration cooperative studies on antihypertensive agents, systolic time intervals (STIs) were recorded before and after 2 or 4 weeks of treatment with hydrochlorothiazide (HCTZ) alone in 320 asymptomatic patients with mild to moderate hypertension. After treatment with HCTZ, left ventricular ejection time corrected for heart rate (delta LVET) was significantly reduced. This decrease is consistent with other hemodynamic observations indicating a reduced preload and stroke volume after administration of thiazides. Electromechanical systole corrected for heart rate (delta QS2) decreased, while the ratio of preejection period to LVET (PEP/LVET) increased, reflecting reduced left ventricular function. PEP did not change. Four step 2 drugs--hydralazine, prazosin, oxprenolol and propranolol--were then added randomly to HCTZ and further recordings of STIs were taken at 1 and 6 months after administration of these drugs. The delta LVET and delta QS2 increased and PEP/LVET decreased, suggesting improved left ventricular function after administration of all 4 agents. These changes may have been due to the added agents or to the recovery of cardiac output that occurs independently during long-term treatment with thiazide diuretic drugs alone. PEP decreased slightly after hydralazine and prazosin and increased slightly after treatment with the beta-blocking drugs, although none of these changes were significant except those during hydralazine treatment. Processing of the STIs was greatly facilitated by the automated system for recording and analyzing the measurements.

Beta-blocker brain concentrations in man

Patients with subarachnoid haemorrhage (SAH) have been shown to benefit from beta-blockade. SAH patients who came to surgery were investigated if they had been receiving chronic (approximately one week) oral treatment with either hydrophilic atenolol (100 mg/day) or one of the following lipophilic beta-blockers: propranolol (80 mg b.i.d.), oxprenolol (80 mg b.i.d.), or metoprolol (100 mg b.i.d.). Cerebrospinal fluid concentrations of beta-blockers did not reflect their concentrations in the brain. Brain concentrations of the three lipophilic beta-blockers were 10-20 times higher than those of atenolol. The approximate brain/plasma concentration ratios were 26 for propranolol, 50 for oxprenolol, 12 for metoprolol, and 0.2 for atenolol. The brain is thus buffered from peak blood concentrations of atenolol, and this may account for the low incidence of CNS-related side-effects with this hydrophilic beta-blocker.

Veterans Administration cooperative study on nadolol as monotherapy and in combination with a diuretic

A series of studies on various therapeutic aspects of beta-adrenergic-blocking drugs was carried out by the Veterans Administration Cooperative Study Group on Antihypertensive Agents. In one study the diastolic blood pressures of 49% of 132 men with mild to moderate hypertension were controlled (less than 90 mm Hg) with once-daily nadolol. In a similar group, 85% were controlled with nadolol plus bendroflumethiazide, both given once daily. Nadolol alone was as effective as diuretic alone, although in another study comparing propranolol and hydrochlorothiazide, the latter was somewhat more effective. In both trials black patients tended to respond better to the diuretic, whereas white patients responded better to the beta blocker. Although high-renin hypertensive patients tended to respond better to the beta blocker and low-renin patients to the diuretic, the relationships were not close enough to provide a dependable guide to treatment. Sixty percent of patients whose blood pressure was not controlled on the nadolol-containing regimens reached goal blood pressure (less than 90 mm Hg) with the addition of hydralazine, 25 to 100 mg twice daily.

Beta-blockers after myocardial infarction

Excellent recent trials have demonstrated beyond reasonable doubt that beta-blockade started during convalescence from confirmed myocardial infarction reduces mortality in the next year or two by about a quarter. Similar confidence does not extend to the mechanisms of action, choice of drug, defining treatment criteria in relation to severity and age, or to the duration of treatment.

Use of beta-blocking agents with group therapy in a smoking withdrawal clinic

A controlled trial was carried out into the relative efficacy of two beta-blocking agents (oxprenolol and metoprolol) as adjuncts to group therapy in a smoking withdrawal clinic. There was no evidence to indicate that these were of specific value in assisting smoking withdrawal.

Effects of moderate salt restriction in hypertensive patients treated with oxprenolol or chlorthalidone

Ninety-five hypertensive out-patients, whose lying diastolic blood pressure was still greater than or equal to 95 mm Hg after a 4-week treatment with oxprenolol slow release 160 mg/day or chlorthalidone 25 mg/day, restricted their daily sodium intake for a 4-week period, while continuing to receive the previous pharmacological therapy. The dietary intervention, appositely formulated to moderately restrict sodium intake, resulted in a high patient compliance as assessed by the significant (p less than 0.01) reduction in the 24-hour urinary sodium excretion. At the end of the 4-week dietary period, a significant (p less than 0.01) decrease in lying and standing systolic and diastolic blood pressure was observed in both the oxprenolol and chlorthalidone treated groups. These results suggest that a moderate reduction in sodium intake, obtained from a low sodium diet characterized by high patient compliance and easily followed in everyday life, is effective in lowering blood pressure in hypertensive patients who don't respond satisfactorily to pharmacological therapy alone.

Efficacy of low-dose captopril given twice daily to patients with essential hypertension uncontrolled by a beta blocker plus thiazide diuretic

Thirty-two patients with moderate to severe essential hypertension whose supine diastolic blood pressure (SDBP) was greater than or equal to 95 mm Hg following 2 weeks' treatment with the optimal dosage of beta blocker-diuretic combination were randomly assigned to the addition of either captopril 25 mg or 50 mg b.i.d. After 6 weeks' treatment, if patients were not normalized (SDBP less than 95 mm Hg), the dose of captopril was doubled for a further 6 weeks. The addition of captopril led to a significant fall in standing and supine diastolic and systolic blood pressure at the end of the sixth and twelfth week of treatment. There was no difference in the change in blood pressure between the two groups. At the end of the study SDBP was normalized in 66% of patients and a further 12.5% had their SDBP reduced by greater than 10%. Captopril 25 or 50 mg administered twice daily proved to be a very effective antihypertensive agent when added to a beta blocker-diuretic combination in patients resistant to optimal doses of these drugs.

Comparison of three different methods of monitoring unwanted effects during antihypertensive therapy

In a double-blind, randomized, crossover, multicenter study performed in 227 hypertensive outpatients, two antihypertensive drugs, oxprenolol and chlorthalidone, were investigated to determine unwanted effects. Three main methodologic procedures were applied: the conventional evaluation of unwanted effects by the physician and involving the whole patient population, the checklist, and the free questionnaire. The latter two were assigned by randomization to the patients themselves. The study showed that unwanted effects seem to be frequently overreported when a checklist is used, whereas the free questionnaire gives more information about the symptoms of the disease than about the tolerance of the drug. The conventional method, when physicians are well-informed and sensitized to the problem, seems to provide more reliable information about unwanted effects of a drug.

[Abnormal ECG and adrenaline-induced arrhythmias in restraint and water immersion stressed mice and effects of oxprenolol]

Male ddY mice were loaded with restraint and water immersion stress (RWIS) for 1 hr, and their ECG was measured by lead II. A considerable decrease of heart rate and remarkable prolongations of PQ, QT and QRS intervals were observed in the ECG of RWIS mice. Then experimental arrhythmias were induced by methacholine or adrenaline (Adr) on RWIS mice, and their frequencies of appearance were examined. The appearances of methacholine-induced ventricular extrasystole, atrio-ventricular (A-V) block, sino-atrial (S-A) block and sinus standstill were higher in RWIS mice than in normal mice, and the appearances of sinus arrhythmia and supraventricular extrasystole were similar to normal mice. The appearance of Adr-induced arrhythmia of any type was significantly higher in RWIS mice than in normal mice. Then protective effects of 3 beta-blockers, oxprenolol, propranolol and carteolol, on the worsening of Adr-induced arrhythmias on RWIS mice were studied. A single administration of 5 or 10 mg/kg of oxprenolol or 5 mg/kg of propranolol inhibited the appearance of extrasystole and A-V block. The effectiveness of three-times administrations of 1 approximately 10 mg/kg of oxprenolol was similar to that of the single administration. These results suggest that oxprenolol shows a strong antiarrhythmic effect by continuous administrations on chronic syndromes in SART mice, and it shows an immediate effect by a single administration on acute syndromes in RWIS mice.

European Infarction Study (E.I.S.). A secondary prevention study with slow release oxprenolol after myocardial infarction: morbidity and mortality

A multicentre, double-blind, randomized study was carried out to compare the effect on survival, cardiac mortality and non-fatal cardiac events of oxprenolol slow release 160 mg b.i.d. compared with placebo in 1741 patients 35 to 69 years of age who had survived acute myocardial infarction. The patients were entered 14-36 days after infarction and were followed for one year. Recruitment was discontinued before the scheduled 4000 patients had been entered. There were 57 deaths (6.6%) in patients randomized with respect to oxprenolol as compared with 45 deaths (5.1%) in patients randomized with respect to placebo. The difference in cumulative mortality rates (30.4%) is not statistically significant. 275 patients from each treatment group discontinued trial medication. The proportion of deaths was noted to be higher in patients who discontinued trial medication (oxprenolol 13.1%; placebo 7.6%) and in patients 65-69 years (oxprenolol 16.7%; placebo 5.6%). In the 1472 patients less than 65 years of age there was a tendency to a lower mortality in 478 'high risk' patients on beta-blockade [oxprenolol 16 patients (6.9%); placebo 25 patients (10.2%)] as compared with a somewhat higher mortality in the corresponding low risk group (oxprenolol 20 patients [4.0%]; placebo 12 patients [2.4%]). In the 1010 patients under 65 years of age who continued on trial medication, 15 patients (3%) in the oxprenolol group and 22 patients (4.3%) in the placebo group died. The overall results in our trial failed to confirm apparently positive effects in other secondary prevention trials. Debate especially concerns patients older than 65 years of age, patients at relatively low risk, and patients who discontinued oxprenolol treatment.

Effect of prazosin on blood pressure and plasma lipids in patients receiving a beta-blocker and diuretic regimen

When prazosin was added to a beta-blocker/diuretic regimen, there was a further and statistically significant (p less than 0.05) reduction in blood pressure (12.7 percent supine diastolic pressure) but no significant change in heart rate. Mean high-density lipoprotein cholesterol increased by 10.8 percent (p less than 0.05) during prazosin treatment whereas very low-density lipoprotein and low-density lipoprotein cholesterol decreased. Together these changes contributed to a significant (p less than 0.05) increase in the ratio of high-density lipoprotein: low-density lipoprotein plus very low-density lipoprotein cholesterol of 13.3 percent. The reduction in total cholesterol was more marked in patients with elevated cholesterol levels (260 mg/100 ml or greater); in this group, total cholesterol and triglyceride levels were significantly reduced (p less than 0.05) during prazosin treatment.

Acute psoriatric arthropathy precipitated by oxprenolol

A previously normal 58-year-old woman developed a widespread psoriatic rash and asymmetrical peripheral polyarthritis a week after beginning treatment with oxprenolol for hypertension. Skin and joint disease resolved simultaneously after drug withdrawal and have not recurred.

Leucine-induced hypoglycemia in a family: effect of diphenylhydantoin, oxprenolol, and diazoxide

The present report describes a mother and 2 children with leucine-induced hypoglycemia (LIH). Hypoglycemic episodes following high-protein meals first appeared at age 4-7 months. Leucine-stimulation tests triggered marked hyperinsulinism and hypoglycemia in the children and a milder but abnormal response in the mother. To evaluate the therapeutic effects and to study the mechanism of hyperinsulinism in LIH, the leucine test was repeated under treatment with diphenylhydantoin, oxprenolol (a beta-blocker), and diazoxide. Diazoxide abolished hyperinsulinism; diphenylhydantoin did not affect the response to leucine; and oxprenolol, tested in the mother only, increased hyperinsulinism and hypoglycemia. Our results indicate that LIH is an autosomal dominant disorder; LIH may persist into adulthood with milder clinical symptoms and chemical response to leucine; diazoxide is the treatment of choice in LIH. Considering the effects of the three agents on stimulated release of insulin, it is concluded that leucine triggers hyperinsulinism by a mechanism different from that of glucose and beta-adrenergic receptors.

Effect of oxprenolol and metoprolol on serum lipid concentration

The aim of the present study was to evaluate whether a reduction in HDL-cholesterol is peculiar to non cardioselective beta blockers or whether it is also produced by cardioselective beta 1-blockers. 16 patients with primary arterial hypertension on a balanced isocaloric diet were given oxprenolol 120 to 240 mg/day or metoprolol 100 to 200 mg/day in a random cross-over study. No significant change was observed after either treatment in fasting blood glucose, serum total cholesterol and triglycerides. HDL-cholesterol concentration was significantly decreased on metoprolol, from 41 to 36 mg/dl (p less than 0.05), while oxprenolol did not affect it at all. The difference might depend on intrinsic sympathomimetic activity which is possessed by oxprenolol and which metoprolol lacks.