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The Cochrane Database of Systematic... Jan 2017Beta-blockers refer to a mixed group of drugs with diverse pharmacodynamic and pharmacokinetic properties. They have shown long-term beneficial effects on mortality and... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Beta-blockers refer to a mixed group of drugs with diverse pharmacodynamic and pharmacokinetic properties. They have shown long-term beneficial effects on mortality and cardiovascular disease (CVD) when used in people with heart failure or acute myocardial infarction. Beta-blockers were thought to have similar beneficial effects when used as first-line therapy for hypertension. However, the benefit of beta-blockers as first-line therapy for hypertension without compelling indications is controversial. This review is an update of a Cochrane Review initially published in 2007 and updated in 2012.
OBJECTIVES
To assess the effects of beta-blockers on morbidity and mortality endpoints in adults with hypertension.
SEARCH METHODS
The Cochrane Hypertension Information Specialist searched the following databases for randomized controlled trials up to June 2016: the Cochrane Hypertension Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL) (2016, Issue 6), MEDLINE (from 1946), Embase (from 1974), and ClinicalTrials.gov. We checked reference lists of relevant reviews, and reference lists of studies potentially eligible for inclusion in this review, and also searched the the World Health Organization International Clinical Trials Registry Platform on 06 July 2015.
SELECTION CRITERIA
Randomised controlled trials (RCTs) of at least one year of duration, which assessed the effects of beta-blockers compared to placebo or other drugs, as first-line therapy for hypertension, on mortality and morbidity in adults.
DATA COLLECTION AND ANALYSIS
We selected studies and extracted data in duplicate, resolving discrepancies by consensus. We expressed study results as risk ratios (RR) with 95% confidence intervals (CI) and conducted fixed-effect or random-effects meta-analyses, as appropriate. We also used GRADE to assess the certainty of the evidence. GRADE classifies the certainty of evidence as high (if we are confident that the true effect lies close to that of the estimate of effect), moderate (if the true effect is likely to be close to the estimate of effect), low (if the true effect may be substantially different from the estimate of effect), and very low (if we are very uncertain about the estimate of effect).
MAIN RESULTS
Thirteen RCTs met inclusion criteria. They compared beta-blockers to placebo (4 RCTs, 23,613 participants), diuretics (5 RCTs, 18,241 participants), calcium-channel blockers (CCBs: 4 RCTs, 44,825 participants), and renin-angiotensin system (RAS) inhibitors (3 RCTs, 10,828 participants). These RCTs were conducted between the 1970s and 2000s and most of them had a high risk of bias resulting from limitations in study design, conduct, and data analysis. There were 40,245 participants taking beta-blockers, three-quarters of them taking atenolol. We found no outcome trials involving the newer vasodilating beta-blockers (e.g. nebivolol).There was no difference in all-cause mortality between beta-blockers and placebo (RR 0.99, 95% CI 0.88 to 1.11), diuretics or RAS inhibitors, but it was higher for beta-blockers compared to CCBs (RR 1.07, 95% CI 1.00 to 1.14). The evidence on mortality was of moderate-certainty for all comparisons.Total CVD was lower for beta-blockers compared to placebo (RR 0.88, 95% CI 0.79 to 0.97; low-certainty evidence), a reflection of the decrease in stroke (RR 0.80, 95% CI 0.66 to 0.96; low-certainty evidence) since there was no difference in coronary heart disease (CHD: RR 0.93, 95% CI 0.81 to 1.07; moderate-certainty evidence). The effect of beta-blockers on CVD was worse than that of CCBs (RR 1.18, 95% CI 1.08 to 1.29; moderate-certainty evidence), but was not different from that of diuretics (moderate-certainty) or RAS inhibitors (low-certainty). In addition, there was an increase in stroke in beta-blockers compared to CCBs (RR 1.24, 95% CI 1.11 to 1.40; moderate-certainty evidence) and RAS inhibitors (RR 1.30, 95% CI 1.11 to 1.53; moderate-certainty evidence). However, there was little or no difference in CHD between beta-blockers and diuretics (low-certainty evidence), CCBs (moderate-certainty evidence) or RAS inhibitors (low-certainty evidence). In the single trial involving participants aged 65 years and older, atenolol was associated with an increased CHD incidence compared to diuretics (RR 1.63, 95% CI 1.15 to 2.32). Participants taking beta-blockers were more likely to discontinue treatment due to adverse events than participants taking RAS inhibitors (RR 1.41, 95% CI 1.29 to 1.54; moderate-certainty evidence), but there was little or no difference with placebo, diuretics or CCBs (low-certainty evidence).
AUTHORS' CONCLUSIONS
Most outcome RCTs on beta-blockers as initial therapy for hypertension have high risk of bias. Atenolol was the beta-blocker most used. Current evidence suggests that initiating treatment of hypertension with beta-blockers leads to modest CVD reductions and little or no effects on mortality. These beta-blocker effects are inferior to those of other antihypertensive drugs. Further research should be of high quality and should explore whether there are differences between different subtypes of beta-blockers or whether beta-blockers have differential effects on younger and older people.
Topics: Adrenergic beta-Antagonists; Adult; Aged; Angiotensin Receptor Antagonists; Antihypertensive Agents; Atenolol; Calcium Channel Blockers; Coronary Disease; Diuretics; Heart Arrest; Humans; Hypertension; Middle Aged; Randomized Controlled Trials as Topic; Stroke
PubMed: 28107561
DOI: 10.1002/14651858.CD002003.pub5 -
The Cochrane Database of Systematic... Oct 2014Stroke affects 15 million people per year worldwide. Despite recent developments in acute stroke treatment, prevention remains very important. Stroke has a high rate of... (Review)
Review
BACKGROUND
Stroke affects 15 million people per year worldwide. Despite recent developments in acute stroke treatment, prevention remains very important. Stroke has a high rate of recurrence; therefore secondary prevention is also important. Many clinical approaches to control risk factors have been proposed. One of these approaches is the prescription of beta-blockers that have effects beyond the reduction of blood pressure, which can reduce the recurrence of stroke.
OBJECTIVES
To evaluate the efficacy of beta-blockers for preventing stroke recurrence and for reducing death and major vascular events in people with a previous stroke or transient ischaemic attack (TIA), and to determine their safety, particularly with regard to the development of diabetes mellitus.
SEARCH METHODS
We searched the Cochrane Stroke Group Trials Register (May 2014), the Cochrane Central Register of Controlled Trials (CENTRAL) and the Cochrane Database of Systematic Reviews (CDSR) (The Cochrane Library 2014, Issue 5), the Database of Abstracts of Reviews of Effects (DARE) (May 2014), MEDLINE (1966 to May 2014), EMBASE (1980 to May 2014), and Latin American and Caribbean Health Sciences Literature (LILACS) (1982 to May 2014). We also searched ongoing trials registers and reference lists.
SELECTION CRITERIA
Randomised controlled trials (RCTs) that included participants with previous stroke or TIA due to arterial thrombosis or embolism. The intervention was any beta-blocker versus control, or beta-blocker plus other treatment versus other treatment.
DATA COLLECTION AND ANALYSIS
Two review authors independently screened the trials identified, appraised quality, and extracted data.
MAIN RESULTS
We included two RCTs involving 2193 participants in the review. Both studies randomised participants to either beta-blocker (atenolol 5 mg) or placebo and were of a high methodological quality. We noted no statistical differences among the groups in risks of fatal and non-fatal stroke (risk ratio (RR) 0.94, 95% confidence interval (CI) 0.76 to 1.18). For other outcomes analysed (major vascular events, death from all causes, death from cardiovascular causes) , we observed no significant differences between the groups. There were minor blood pressure reductions in the intervention group. Neither of the included studies reported the occurrence of diabetes among their outcomes or assessed quality of life. Adverse events were significantly more frequent in participants taking atenolol than in those given placebo, and were the most common reason given for discontinuing treatment (RR 1.85, 95% CI 1.45 to 2.35).
AUTHORS' CONCLUSIONS
To date, no available evidence supports the routine use of beta-blockers for secondary prevention after stroke or TIA. More studies with larger samples are needed.
Topics: Adrenergic beta-1 Receptor Antagonists; Atenolol; Humans; Ischemic Attack, Transient; Randomized Controlled Trials as Topic; Recurrence; Secondary Prevention; Stroke
PubMed: 25317988
DOI: 10.1002/14651858.CD007890.pub3 -
Molecules (Basel, Switzerland) May 2021Enzymes are highly specific biological catalysts that accelerate the rate of chemical reactions within the cell. Our knowledge of how enzymes work remains incomplete.... (Review)
Review
Enzymes are highly specific biological catalysts that accelerate the rate of chemical reactions within the cell. Our knowledge of how enzymes work remains incomplete. Computational methodologies such as molecular mechanics (MM) and quantum mechanical (QM) methods play an important role in elucidating the detailed mechanisms of enzymatic reactions where experimental research measurements are not possible. Theories invoked by a variety of scientists indicate that enzymes work as structural scaffolds that serve to bring together and orient the reactants so that the reaction can proceed with minimum energy. Enzyme models can be utilized for mimicking enzyme catalysis and the development of novel prodrugs. Prodrugs are used to enhance the pharmacokinetics of drugs; classical prodrug approaches focus on alternating the physicochemical properties, while chemical modern approaches are based on the knowledge gained from the chemistry of enzyme models and correlations between experimental and calculated rate values of intramolecular processes (enzyme models). A large number of prodrugs have been designed and developed to improve the effectiveness and pharmacokinetics of commonly used drugs, such as anti-Parkinson (dopamine), antiviral (acyclovir), antimalarial (atovaquone), anticancer (azanucleosides), antifibrinolytic (tranexamic acid), antihyperlipidemia (statins), vasoconstrictors (phenylephrine), antihypertension (atenolol), antibacterial agents (amoxicillin, cephalexin, and cefuroxime axetil), paracetamol, and guaifenesin. This article describes the works done on enzyme models and the computational methods used to understand enzyme catalysis and to help in the development of efficient prodrugs.
Topics: Acyclovir; Atenolol; Atovaquone; Catalysis; Chemistry, Pharmaceutical; Decitabine; Dopamine; Enzymes; Hydrogen-Ion Concentration; Hydrolysis; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Molecular Conformation; Nucleosides; Phenylephrine; Prodrugs; Protons; Quantum Theory; Software; Technology, Pharmaceutical; Temperature; Tranexamic Acid
PubMed: 34071328
DOI: 10.3390/molecules26113248 -
The New England Journal of Medicine Jan 2021A polypill comprising statins, multiple blood-pressure-lowering drugs, and aspirin has been proposed to reduce the risk of cardiovascular disease. (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
A polypill comprising statins, multiple blood-pressure-lowering drugs, and aspirin has been proposed to reduce the risk of cardiovascular disease.
METHODS
Using a 2-by-2-by-2 factorial design, we randomly assigned participants without cardiovascular disease who had an elevated INTERHEART Risk Score to receive a polypill (containing 40 mg of simvastatin, 100 mg of atenolol, 25 mg of hydrochlorothiazide, and 10 mg of ramipril) or placebo daily, aspirin (75 mg) or placebo daily, and vitamin D or placebo monthly. We report here the outcomes for the polypill alone as compared with matching placebo, for aspirin alone as compared with matching placebo, and for the polypill plus aspirin as compared with double placebo. For the polypill-alone and polypill-plus-aspirin comparisons, the primary outcome was death from cardiovascular causes, myocardial infarction, stroke, resuscitated cardiac arrest, heart failure, or revascularization. For the aspirin comparison, the primary outcome was death from cardiovascular causes, myocardial infarction, or stroke. Safety was also assessed.
RESULTS
A total of 5713 participants underwent randomization, and the mean follow-up was 4.6 years. The low-density lipoprotein cholesterol level was lower by approximately 19 mg per deciliter and systolic blood pressure was lower by approximately 5.8 mm Hg with the polypill and with combination therapy than with placebo. The primary outcome for the polypill comparison occurred in 126 participants (4.4%) in the polypill group and in 157 (5.5%) in the placebo group (hazard ratio, 0.79; 95% confidence interval [CI], 0.63 to 1.00). The primary outcome for the aspirin comparison occurred in 116 participants (4.1%) in the aspirin group and in 134 (4.7%) in the placebo group (hazard ratio, 0.86; 95% CI, 0.67 to 1.10). The primary outcome for the polypill-plus-aspirin comparison occurred in 59 participants (4.1%) in the combined-treatment group and in 83 (5.8%) in the double-placebo group (hazard ratio, 0.69; 95% CI, 0.50 to 0.97). The incidence of hypotension or dizziness was higher in groups that received the polypill than in their respective placebo groups.
CONCLUSIONS
Combined treatment with a polypill plus aspirin led to a lower incidence of cardiovascular events than did placebo among participants without cardiovascular disease who were at intermediate cardiovascular risk. (Funded by the Wellcome Trust and others; TIPS-3 ClinicalTrials.gov number, NCT01646437.).
Topics: Aged; Anticholesteremic Agents; Antihypertensive Agents; Aspirin; Atenolol; Blood Pressure; Cardiovascular Diseases; Cholesterol, LDL; Drug Combinations; Drug Therapy, Combination; Female; Humans; Hydrochlorothiazide; Incidence; Male; Medication Adherence; Middle Aged; Platelet Aggregation Inhibitors; Risk Factors; Simvastatin
PubMed: 33186492
DOI: 10.1056/NEJMoa2028220 -
Materials (Basel, Switzerland) Mar 2024Adsorptive, catalytic, and antibacterial properties of clinoptilolite-rich tuffs (ZT) are presented here. ZT transformed into Fe-containing ZT (Fe-ZT) removes various... (Review)
Review
Adsorptive, catalytic, and antibacterial properties of clinoptilolite-rich tuffs (ZT) are presented here. ZT transformed into Fe-containing ZT (Fe-ZT) removes various organic and inorganic anions from water. Fe-ZT, which contains selenium, is beneficial for growing mushrooms. The fungi convert inorganic Se from Fe-ZT into a more useful organically bonded form. ZT and Fe-ZT as supplements retain nitrogen and potassium in sandy, silty loam and silty clay soils. ZT shows an affinity toward toxic metal cations, which are essential for cleaning contaminated water. The adsorption of atenolol, acetylsalicylic, and salicylic acid onto M-ZT (M-Cu, Mn, Ni, or Zn) from water solutions suggests that both the natures of M and pharmaceuticals have a significant impact on the adsorption mechanism and determine the adsorption capability of the ZT. ZT is an excellent carrier for ultrafine (2-5 nm) nano oxide particles, which have been shown to have catalytic activity in different chemical processes and photodegradation reactions of organic pollutants. ZT can also be transformed into SO-SnO-ZT, which is catalytically active as a solid acid. M-ZT is an effective carrier of valuable bacteria. Ag-ZT possesses beneficial bactericidal activity in disinfecting water and soil remediation.
PubMed: 38541460
DOI: 10.3390/ma17061306 -
The American Journal of Case Reports Jan 2022BACKGROUND BRASH syndrome is a newly recognized clinical entity characterized by bradycardia, renal failure, atrioventricular blockade, shock, and hyperkalemia. Patients...
BACKGROUND BRASH syndrome is a newly recognized clinical entity characterized by bradycardia, renal failure, atrioventricular blockade, shock, and hyperkalemia. Patients with BRASH syndrome often have severe bradycardia that is refractory to antidotes and chronotropic medications. In these situations, transvenous pacemaker and renal replacement therapy may be necessary. Therefore, rapid diagnosis and correct management of this entity are crucial to reduce mortality. We report a case and the management of BRASH syndrome in the Emergency Department. CASE REPORT A 76-year-old man with chronic kidney disease stage 3, essential hypertension and psoriasis, and receiving atenolol presented to the Emergency Department with lethargy and weakness that started 3 days ago, with rapid deterioration into shock. His initial laboratory tests revealed hyperkalemia, metabolic acidosis, and acute kidney injury. His initial electrocardiogram was remarkable for sinus bradycardia with junctional escape rhythm with ventricular rate of 26 bpm. A chest X-ray was normal. Transthoracic echocardiogram showed normal systolic and diastolic function. Atenolol was immediately held. He was treated with potassium-lowering agents and vasoactive drugs. Due to the persistence of bradycardia, even after reversal of hyperkalemia, a temporary transvenous pacemaker was placed. Renal replacement therapy was not required. Renal function improved and heart rate stabilized at 80 bpm. The patient was discharged and advised to avoid atrioventricular-blocking agents, with Cardiology follow-up. CONCLUSIONS BRASH syndrome is a serious complication due to a combination of hyperkalemia, hypotension, and bradycardia in the setting of kidney dysfunction and medications that block the atrioventricular node. Hemodynamic support and temporary pacemaker use may be needed to manage this entity.
Topics: Aged; Arrhythmias, Cardiac; Bradycardia; Electrocardiography; Humans; Hyperkalemia; Male; Sick Sinus Syndrome
PubMed: 35058422
DOI: 10.12659/AJCR.934600