Comparison of casual, ambulatory and self-measured blood pressure in a study of nitrendipine vs bisoprolol

Therapeutic applications of circadian rhythms for the cardiovascular system

The cardiovascular system exhibits dramatic time-of-day dependent rhythms, for example the diurnal variation of heart rate, blood pressure, and timing of onset of adverse cardiovascular events such as heart attack and sudden cardiac death. Over the past decade, the circadian clock mechanism has emerged as a crucial factor regulating these daily fluctuations. Most recently, these studies have led to a growing clinical appreciation that targeting circadian biology offers a novel therapeutic approach toward cardiovascular (and other) diseases. Here we describe leading-edge therapeutic applications of circadian biology including (1) timing of therapy to maximize efficacy in treating heart disease (chronotherapy); (2) novel biomarkers discovered by testing for genomic, proteomic, metabolomic, or other factors at different times of day and night (chronobiomarkers); and (3) novel pharmacologic compounds that target the circadian mechanism with potential clinical applications (new chronobiology drugs). Cardiovascular disease remains a leading cause of death worldwide and new approaches in the management and treatment of heart disease are clearly warranted and can benefit patients clinically.

In Silico comparison between metoprolol succinate and bisoprolol on 24-hour systolic blood pressures

Objective

To compare the effects of bisoprolol and metoprolol CR/ZOK (metoprolol succinate controlled release) on systolic blood pressure (bp_sys) over a 24-h period in an in silico model.

Methods

On the basis of the observed data from ambulatory blood pressure measurements (ABPM), a model with an appropriate distribution and correlation structure was derived for simulation of 24-h bp_sys patterns during treatment with commonly studied doses, assumed to be equipotent, of bisoprolol and metoprolol CR/ZOK. Input into the simulations was aligned with the available data on the diurnal efficacy and pharmacology profiles of these substances. The validity of the model was tested in a bootstrap model.

Results

The simulation model reproduced the observed data with high congruence (p = 1.0). The mean 24-h bp_sys values did not significantly differ between the two simulated groups (estimated overall change in bp_sys [∆bp_sys] for metoprolol versus bisoprolol = 2.7 mmHg [95 % confidence interval −0.3 to 5.7 mmHg]; p = 0.08). There were clear diurnal differences, with bisoprolol being more effective earlier and metoprolol CR/ZOK being more effective later in the 24-h day. A validity test with 100 repeated samples gave an overall mean group difference of 1.4 ± 3.59 mmHg (p = 0.63 relative to simulation).

Conclusion

In a robust model for the simulation of 24-h ABPM, comparisons between bisoprolol and metoprolol CR/ZOK indicate a comparable overall blood pressure-lowering effect but different diurnal patterns, consistent with the pharmacokinetics of the two drugs. This difference may be of clinical relevance, given the recognized diurnal pattern of cardiovascular events.

Effects of the hormone therapy, drospirenone and 17-beta estradiol, on early morning blood pressure in postmenopausal women with hypertension

Drospirenone (DRSP), is a unique progestin with antimineralocorticoid activity that has been combined with 17-beta estradiol (E2) for the treatment of symptoms of the menopause in women with hypertension. We assessed the effects of DRSP/E2, E2 alone, and placebo on early morning systolic blood pressure (BP) as well as the rate of rise in systolic BP in 748 postmenopausal women with stage 1 and 2 hypertension at baseline and after 8 weeks of double-blind therapy. Patient characteristics (mean age, 56.5 years, 73% to 77% Caucasian; 13% to 17% African-American) and the clinic (152/95 mm Hg) and 24-hour BP (139/83 mm Hg) measurements were similar at baseline. The early morning systolic BP was reduced significantly on DRSP at 3 mg, 2 mg, and 1 mg with E2 compared with placebo, while E2 alone was similar to placebo. The reductions in early morning systolic BP were larger with increasing dose. Changes in the rate of rise in systolic BP between the lowest values during sleep and following a plateau period post-awakening was significant for the 3 mg DRSP group. In conclusion, DRSP/E2 induced significant reductions in early morning systolic BP in post-menopausal women. This attribute could play a potential role in reducing some of the untoward cardiac and cerebrovascular events that have been observed in studies of other progestins/estrogens in postmenopausal women.

Anti-ischemic and antiarrhythmic effectiveness of long-term bisoprolol therapy in patients with myocardial infarction

Aim. To study the effects of long-term bisoprolol (B) therapy on exercise capacity (EC) dynamics, ventricular arrhythmia (VA), and clinical course in patients with myocardial infarction (MI). Material and methods. The study included 114 men with MI (age 30-63 years), receiving long-term B treatment (2,5-10 mg once a day). The parameters assessed included EC dynamics, VA, and clinical course of the disease. Results. Patients with sub-acute MI were characterised by low EC and VA presence, including life-threatening VA forms. Long-term B treatment was associated with a significant reduction in angina attack rate (by 3,9 times) and in the number of nitroglycerin tablets per week (by 4,3 times). In most patients (79,7%), B therapy increased the work performed during stress test (+99%), EC (+43,4%), and exercise time (+52%). In 44 patients (55,7%), an antiarrhythmic effect was observed, including the individuals with high-grade VA (13 out of 15). Long-term B treatment also improved the clinical course of the disease, significantly reducing the end-point rates (in 86,1%). Conclusion. Early started, adequate-dose long-term B therapy improved clinical course of the disease and demonstrated good anti-ischemic, antianginal, and antiarrhythmic effects in MI patients, including those with life-threatening VA forms.

Telemonitoring of blood pressure self measurement in the OLMETEL study

OBJECTIVE

To investigate the feasibility of blood pressure (BP) telemonitoring in previous uncontrolled hypertensives treated with olmesartan medoxomil in a clinical practice setting.

METHODS

Patients (n = 53) with untreated, uncontrolled or insufficiently treated hypertension were selected by physicians to receive olmesartan medoxomil 10-40 mg/day for 12 weeks. Office BP values were determined by a physician at baseline and after 12 weeks' treatment; BP self-measurement (BPSM) was conducted throughout the 12-week treatment period using a TensioPhone TP2 telemonitoring device; BP values were stored and automatically downloaded to a remote service centre via standard telephone lines.

RESULTS

Olmesartan medoxomil produced statistically significant reductions from baseline in both systolic and diastolic office BP and BPSM values. In contrast to office BP, telemonitoring of BPSM allowed the early identification of responders (e.g., after 2-3 weeks' treatment). Blood pressure reduction with olmesartan medoxomil was greater for office BP than for BPSM values. Normalization of BP was achieved in 64.2% of the patients using office BP measurement compared with 36.4% using BPSM. Blood pressure self-measurement showed no significant difference between morning and evening BP measurements or between the morning : evening BP ratio at baseline and after nine weeks of olmesartan medoxomil treatment. Compliance and tolerability were good or very good in most patients.

CONCLUSION

In a 'real-life' clinical practice setting, telemonitoring of BPSM was an effective technique that was partially affected by patient non-compliance. Olmesartan medoxomil provided effective and reliable BP-lowering, which was maintained throughout the 24-hour period.

Can NPs rely on self-blood pressure measurements?

The development of relatively inexpensive and automated devices has stimulated the use of self or home blood pressure (BP) monitors. This article provides a guide for NPs to understand when self-BP measurement (SBPM) is a reliable alternative to traditional in-office measurements.

Significance of blood pressure self-measurement as compared with office blood pressure measurement and ambulatory 24-hour blood pressure measurement in pharmacological studies

With the increasing use of blood pressure self-measurement in pharmacological studies, the question arises as to whether this method can replace office blood pressure measurement or ambulatory 24-h blood pressure measurement for testing and comparing the efficacy of antihypertensives. Ambulatory 24-h blood pressure measurement or self-measurement available for analysis can be obtained in 70 to 90% of patients. Self-measurement shows a better correlation with the prognostically relevant ambulatory 24-h blood pressure measurement than office blood pressure measurement for appraising the antihypertensive effect. Although similar antihypertensive effects were found for ambulatory 24-h blood pressure measurement and self-measurement in the group comparison, substantial discrepancies can be observed in the individual patient owing to the different nature of these two methods of measurement. Both ambulatory 24-h blood pressure measurement and self-measurement are superior to office blood pressure measurement in terms of their reproducibility. This increases the sensitivity of clinical studies and reduces the number of cases required. Owing to the white-coat effect, variable compliance and drug holidays and their effects on the efficacy of antihypertensive medication are not detected by office blood pressure measurement and ambulatory 24-h blood pressure measurement. Self-measurement detects drug holidays, which are reflected in an increase of the blood pressure measurement values, and per se promotes compliance. Self-measurements and ambulatory 24-h measurements in pharmacological studies must be regarded as complementary, so that it is appropriate to use both methods whenever possible. Data management, data analysis and monitoring in pharmacological studies are facilitated by instruments with automatic data storage which allows telemonitoring.

Self-monitoring of blood pressure should be used in clinical trials

The number of studies of the efficacy of drugs in hypertension and of their effects on morbidity and mortality continues to be large. Traditionally such studies were carried out by measuring the blood pressure (BP) in the office. Recently, there has been an increasing use of other approaches, such as self-measurement. The advantages of this technique may be the achievement of greater precision of measurement, explained by elimination of the white-coat effect, reduction in placebo effect and reduction in variability of BP. Some have even noted a greater reproducibility than using ambulatory BP monitoring. We now have available reference values and normal ranges for self-BP monitoring. The feasibility and the limitations of self-BP measurement are also known. Self-measurement allows multiple recordings of BP over the short term as well as over the long term. Moreover, the compliance of this technique is satisfying. The analysis of the data requires precise recommendations. One cannot refer to trough : peak ratio, which is used in ambulatory recordings. However, other methods of analysis such as evening BP : morning BP ratio or measures taken after taking treatment are useful. The number of subjects needed for a study is much smaller than in a study performed using office measurements for a similar or better statistical power. Such a method has a higher predictive value than clinic measurement both for study of end organ damage and for morbidity and mortality. Finally home measurement is much less costly. In conclusion, provided one uses validated equipment and if one follows recommendations for each measurement and for the succession of measurements, then self-measurement of BP at home seems a useful and practical tool for therapeutic trials.

Bisoprolol: is this just another beta-blocker for hypertension or angina?

OBJECTIVE

To review the pharmacology, pharmacokinetics, and clinical experience with bisoprolol and make recommendations regarding its potential clinical usefulness, as well as considerations for formulary inclusion.

DATA SOURCES

Reference citations were sought from Index Medicus and Science Citation Index. Data were collected from abstracts and articles describing experimental studies or blind clinical trials.

STUDY SELECTION

Studies designed in a randomized, blind, and placebo-controlled manner were emphasized. Studies also were included if bisoprolol was evaluated comparatively with other agents in a randomized, blind fashion.

DATA EXTRACTION

Data from human studies published in English were evaluated. Studies were assessed by sample size and the clarity of descriptions of methods and results.

DATA SYNTHESIS

Bisoprolol reduces systolic and diastolic blood pressures in patients with hypertension for a 24-hour dosing interval and is associated with beneficial hemodynamic effects in patients with myocardial ischemia. It is devoid of intrinsic sympathomimetic activity and membrane-stabilizing effects at therapeutic dosages. In patients with hypertension, bisoprolol diminishes plasma renin activity, platelet aggregation, effective renal plasma flow, and creatinine clearance. Bisoprolol has minimal effects on glucose tolerance and plasma lipid profiles. Monotherapy with bisoprolol is as effective as with atenolol, nitrendipine, or nifedipine. Low-dose combination therapy with hydrochlorothiazide is at least as effective as either bisoprolol or hydrochlorothiazide alone. Preliminary experience in the management of angina pectoris suggests that bisoprolol is at least as efficacious as atenolol or verapamil. Thus far, reported adverse effects are similar to those of other beta-blockers. No clinically important drug interactions have been reported at this time.