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BMJ Clinical Evidence Nov 2014Acute atrial fibrillation is rapid, irregular, and chaotic atrial activity of recent onset. Various definitions of acute atrial fibrillation have been used in the... (Review)
Review
INTRODUCTION
Acute atrial fibrillation is rapid, irregular, and chaotic atrial activity of recent onset. Various definitions of acute atrial fibrillation have been used in the literature, but for the purposes of this review we have included studies where atrial fibrillation may have occurred up to 7 days previously. Risk factors for acute atrial fibrillation include increasing age, cardiovascular disease, alcohol, diabetes, and lung disease. Acute atrial fibrillation increases the risk of stroke and heart failure. The condition resolves spontaneously within 24 to 48 hours in more than 50% of people; however, many people will require interventions to control heart rate or restore sinus rhythm.
METHODS AND OUTCOMES
We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of interventions to prevent embolism, for conversion to sinus rhythm, and to control heart rate in people with recent-onset atrial fibrillation (within 7 days) who are haemodynamically stable? We searched: Medline, Embase, The Cochrane Library, and other important databases up to April 2014 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).
RESULTS
We found 26 studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.
CONCLUSIONS
In this systematic review, we present information relating to the effectiveness and safety of the following interventions: amiodarone, antithrombotic treatment before cardioversion, atenolol, bisoprolol, carvedilol, digoxin, diltiazem, direct current cardioversion, flecainide, metoprolol, nebivolol, propafenone, sotalol, timolol, and verapamil.
Topics: Acute Disease; Anti-Arrhythmia Agents; Atrial Fibrillation; Electric Countershock; Humans; Safety
PubMed: 25430048
DOI: No ID Found -
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 -
The Cochrane Database of Systematic... Sep 2013Beta (β) blockers are indicated for use in coronary artery disease (CAD). However, optimal therapy for people with CAD accompanied by intermittent claudication has been... (Review)
Review
BACKGROUND
Beta (β) blockers are indicated for use in coronary artery disease (CAD). However, optimal therapy for people with CAD accompanied by intermittent claudication has been controversial because of the presumed peripheral haemodynamic consequences of beta blockers, leading to worsening symptoms of intermittent claudication. This is an update of a review first published in 2008.
OBJECTIVES
To quantify the potential harmful effects of beta blockers on maximum walking distance, claudication distance, calf blood flow, calf vascular resistance and skin temperature when used in patients with peripheral arterial disease (PAD).
SEARCH METHODS
For this update, the Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched the Specialised Register (last searched March 2013) and the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, 2013, Issue 2).
SELECTION CRITERIA
Randomised controlled trials (RCTs) evaluating the role of both selective (β1) and non-selective (β1 and β2) beta blockers compared with placebo. We excluded trials that compared different types of beta blockers.
DATA COLLECTION AND ANALYSIS
Primary outcome measures were claudication distance in metres, time to claudication in minutes and maximum walking distance in metres and minutes (as assessed by treadmill).Secondary outcome measures included calf blood flow (mL/100 mL/min), calf vascular resistance and skin temperature (ºC).
MAIN RESULTS
We included six RCTs that fulfilled the above criteria, with a total of 119 participants. The beta blockers studied were atenolol, propranolol, pindolol and metoprolol. All trials were of poor quality with the drugs administered over a short time (10 days to two months). None of the primary outcomes were reported by more than one study. Similarly, secondary outcome measures, with the exception of vascular resistance (as reported by three studies), were reported, each by only one study. Pooling of such results was deemed inappropriate. None of the trials showed a statistically significant worsening effect of beta blockers on time to claudication, claudication distance and maximal walking distance as measured on a treadmill, nor on calf blood flow, calf vascular resistance and skin temperature, when compared with placebo. No reports described adverse events associated with the beta blockers studied.
AUTHORS' CONCLUSIONS
Currently, no evidence suggests that beta blockers adversely affect walking distance, calf blood flow, calf vascular resistance and skin temperature in people with intermittent claudication. However, because of the lack of large published trials, beta blockers should be used with caution, if clinically indicated.
Topics: Adrenergic beta-Antagonists; Atenolol; Humans; Intermittent Claudication; Metoprolol; Peripheral Vascular Diseases; Pindolol; Propranolol; Randomized Controlled Trials as Topic; Regional Blood Flow; Walking
PubMed: 24027118
DOI: 10.1002/14651858.CD005508.pub3 -
Journal of General Internal Medicine Sep 2013Systematic review of preventive pharmacologic treatments for community-dwelling adults with episodic migraine. (Meta-Analysis)
Meta-Analysis
OBJECTIVES
Systematic review of preventive pharmacologic treatments for community-dwelling adults with episodic migraine.
DATA SOURCES
Electronic databases through May 20, 2012.
ELIGIBILITY CRITERIA
English-language randomized controlled trials (RCTs) of preventive drugs compared to placebo or active treatments examining rates of ≥50 % reduction in monthly migraine frequency or improvement in quality of life.
STUDY APPRAISAL AND SYNTHESIS METHODS
We assessed risk of bias and strength of evidence and conducted random effects meta-analyses of absolute risk differences and Bayesian network meta-analysis.
RESULTS
Of 5,244 retrieved references, 215 publications of RCTs provided mostly low-strength evidence because of the risk of bias and imprecision. RCTs examined 59 drugs from 14 drug classes. All approved drugs, including topiramate (9 RCTs), divalproex (3 RCTs), timolol (3 RCTs), and propranolol (4 RCTs); off-label beta blockers metoprolol (4 RCTs), atenolol (1 RCT), nadolol (1 RCT), and acebutolol (1 RCT); angiotensin-converting enzyme inhibitors captopril (1 RCT) and lisinopril (1 RCT); and angiotensin II receptor blocker candesartan (1 RCT), outperformed placebo in reducing monthly migraine frequency by ≥50 % in 200-400 patients per 1,000 treated. Adverse effects leading to treatment discontinuation (68 RCTs) were greater with topiramate, off-label antiepileptics, and antidepressants than with placebo. Limited direct evidence as well as frequentist and exploratory network Bayesian meta-analysis showed no statistically significant differences in benefits between approved drugs. Off-label angiotensin-inhibiting drugs and beta-blockers were most effective and tolerable for episodic migraine prevention.
LIMITATIONS
We did not quantify reporting bias or contact principal investigators regarding unpublished trials.
CONCLUSIONS
Approved drugs prevented episodic migraine frequency by ≥50 % with no statistically significant difference between them. Exploratory network meta-analysis suggested that off-label angiotensin-inhibiting drugs and beta-blockers had favorable benefit-to-harm ratios. Evidence is lacking for long-term effects of drug treatments (i.e., trials of more than 3 months duration), especially for quality of life.
Topics: Adult; Anticonvulsants; Evidence-Based Medicine; Humans; Migraine Disorders; Quality of Life; Randomized Controlled Trials as Topic; Treatment Outcome
PubMed: 23592242
DOI: 10.1007/s11606-013-2433-1 -
BMJ (Clinical Research Ed.) Jan 2013To clarify whether any particular β blocker is superior in patients with heart failure and reduced ejection fraction or whether the benefits of these agents are mainly... (Comparative Study)
Comparative Study Meta-Analysis Review
OBJECTIVE
To clarify whether any particular β blocker is superior in patients with heart failure and reduced ejection fraction or whether the benefits of these agents are mainly due to a class effect.
DESIGN
Systematic review and network meta-analysis of efficacy of different β blockers in heart failure.
DATA SOURCES
CINAHL(1982-2011), Cochrane Collaboration Central Register of Controlled Trials (-2011), Embase (1980-2011), Medline/PubMed (1966-2011), and Web of Science (1965-2011).
STUDY SELECTION
Randomized trials comparing β blockers with other β blockers or other treatments.
DATA EXTRACTION
The primary endpoint was all cause death at the longest available follow-up, assessed with odds ratios and Bayesian random effect 95% credible intervals, with independent extraction by observers.
RESULTS
21 trials were included, focusing on atenolol, bisoprolol, bucindolol, carvedilol, metoprolol, and nebivolol. As expected, in the overall analysis, β blockers provided credible mortality benefits in comparison with placebo or standard treatment after a median of 12 months (odds ratio 0.69, 0.56 to 0.80). However, no obvious differences were found when comparing the different β blockers head to head for the risk of death, sudden cardiac death, death due to pump failure, or drug discontinuation. Accordingly, improvements in left ventricular ejection fraction were also similar irrespective of the individual study drug.
CONCLUSION
The benefits of β blockers in patients with heart failure with reduced ejection fraction seem to be mainly due to a class effect, as no statistical evidence from current trials supports the superiority of any single agent over the others.
Topics: Adrenergic beta-Antagonists; Bayes Theorem; Heart Failure; Humans; Odds Ratio; Randomized Controlled Trials as Topic; Stroke Volume; Treatment Outcome
PubMed: 23325883
DOI: 10.1136/bmj.f55 -
BMC Medicine Apr 2012We conducted a systematic review of evidence from randomized controlled trials to answer the following research question: What are the relative effects of different... (Comparative Study)
Comparative Study Meta-Analysis Review
BACKGROUND
We conducted a systematic review of evidence from randomized controlled trials to answer the following research question: What are the relative effects of different classes of antihypertensive drugs in reducing the incidence of cardiovascular disease outcomes for healthy people at risk of cardiovascular disease?
METHODS
We searched MEDLINE, EMBASE, AMED (up to February 2011) and CENTRAL (up to May 2009), and reference lists in recent systematic reviews. Titles and abstracts were assessed for relevance and those potentially fulfilling our inclusion criteria were then assessed in full text. Two reviewers made independent assessments at each step. We selected the following main outcomes: total mortality, myocardial infarction and stroke. We also report on angina, heart failure and incidence of diabetes. We conducted a multiple treatments meta-analysis using random-effects models. We assessed the quality of the evidence using the GRADE-instrument.
RESULTS
We included 25 trials. Overall, the results were mixed, with few significant differences, and with no drug-class standing out as superior across multiple outcomes. The only significant finding for total mortality based on moderate to high quality evidence was that beta-blockers (atenolol) were inferior to angiotensin receptor blockers (ARB) (relative risk (RR) 1.14; 95% credibility interval (CrI) 1.02 to 1.28). Angiotensin converting enzyme (ACE)-inhibitors came out inferior to calcium-channel blockers (CCB) regarding stroke-risk (RR 1.19; 1.03 to 1.38), but superior regarding risk of heart failure (RR 0.82; 0.69 to 0.94), both based on moderate quality evidence. Diuretics reduced the risk of myocardial infarction compared to beta-blockers (RR 0.82; 0.68 to 0.98), and lowered the risk of heart failure compared to CCB (RR 0.73; 0.62 to 0.84), beta-blockers (RR 0.73; 0.54 to 0.96), and alpha-blockers (RR 0.51; 0.40 to 0.64). The risk of diabetes increased with diuretics compared to ACE-inhibitors (RR 1.43; 1.12 to 1.83) and CCB (RR 1.27; 1.05 to 1.57).
CONCLUSION
Based on the available evidence, there seems to be little or no difference between commonly used blood pressure lowering medications for primary prevention of cardiovascular disease. Beta-blockers (atenolol) and alpha-blockers may not be first-choice drugs as they were the only drug-classes that were not significantly superior to any other, for any outcomes. Review registration: CRD database ("PROSPERO") CRD42011001066.
Topics: Antihypertensive Agents; Chemoprevention; Humans; Incidence; Myocardial Infarction; Primary Prevention; Randomized Controlled Trials as Topic; Stroke; Survival Analysis; Treatment Outcome
PubMed: 22480336
DOI: 10.1186/1741-7015-10-33 -
BMJ Clinical Evidence Feb 2011Pre-eclampsia (raised blood pressure and proteinuria) complicates 2% to 8% of pregnancies, and raises morbidity and mortality in the mother and child. Pre-eclampsia is... (Review)
Review
INTRODUCTION
Pre-eclampsia (raised blood pressure and proteinuria) complicates 2% to 8% of pregnancies, and raises morbidity and mortality in the mother and child. Pre-eclampsia is more common in women with multiple pregnancy and in those who have conditions associated with microvascular disease.
METHODS AND OUTCOMES
We conducted a systematic review and aimed to answer the following clinical questions: what are the effects of preventive interventions in women at risk of pre-eclampsia? What are the effects of interventions in women who develop mild to moderate hypertension during pregnancy? What are the effects of interventions in women who develop severe pre-eclampsia or very high blood pressure during pregnancy? What is the best choice of anticonvulsant for women with eclampsia? We searched: Medline, Embase, The Cochrane Library, and other important databases up to February 2010 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).
RESULTS
We found 69 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.
CONCLUSIONS
In this systematic review we present information relating to the effectiveness and safety of the following interventions: anticonvulsants, antihypertensive drugs, antioxidants, antiplatelet drugs, atenolol, bed rest, hospital admission, or day care, calcium supplementation, choice of analgesia during labour, early delivery (interventionist care), evening primrose oil, fish oil, glyceryl trinitrate, magnesium supplementation, plasma volume expansion, and salt restriction.
Topics: Anticonvulsants; Eclampsia; Female; Humans; Hypertension; Infant, Low Birth Weight; Mothers; Pre-Eclampsia; Pregnancy; Proteinuria; Time Factors
PubMed: 21718554
DOI: No ID Found -
The Cochrane Database of Systematic... Oct 2008Beta (ss) blockers are indicated for use in coronary artery disease (CAD). However, optimal therapy for people with CAD accompanied by intermittent claudication has been... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Beta (ss) blockers are indicated for use in coronary artery disease (CAD). However, optimal therapy for people with CAD accompanied by intermittent claudication has been controversial due to the presumed peripheral haemodynamic consequences of beta blockers, leading to worsening symptoms of intermittent claudication.
OBJECTIVES
To quantify the potential harm of beta blockers on maximum walking distance, claudication distance, calf blood flow, calf vascular resistance, and skin temperature when used in patients with peripheral arterial disease (PAD).
SEARCH STRATEGY
The Cochrane Peripheral Vascular Diseases (PVD) Group searched for publications describing randomised controlled trials (RCTs) of beta blockers in PAD in their Trials Register (last searched 6 May 2008) and the Cochrane Central Register of Controlled Trials (CENTRAL) (last searched The Cochrane Library 2008, Issue 2). We handsearched relevant journals and conference proceedings.
SELECTION CRITERIA
Randomised controlled trials evaluating the role of both selective (beta1) and non-selective (beta1 and beta2) beta blockers compared with placebo. We excluded trials comparing different types of beta blockers.
DATA COLLECTION AND ANALYSIS
Primary outcome measures were claudication distance in metres, and the time to claudication in minutes, and maximum walking distance in metres and minutes (as assessed by treadmill).Secondary outcome measures were calf blood flow (ml/100 ml/min), calf vascular resistance, and skin temperature (degrees C).
MAIN RESULTS
We included six RCTs fulfilling the above criteria, with a total of 119 patients. The beta blockers studied were atenolol, propranolol, pindolol, and metoprolol. None of the trials showed a statistically significant worsening effect of beta blockers on either the primary or secondary outcomes. There were no reports of any adverse events with the beta blockers studied.
AUTHORS' CONCLUSIONS
There is currently no evidence that beta blockers adversely affect walking distance in people with intermittent claudication. However, due to the lack of large published trials beta blockers should be used with caution if clinically indicated.
Topics: Adrenergic beta-Antagonists; Atenolol; Humans; Intermittent Claudication; Metoprolol; Peripheral Vascular Diseases; Pindolol; Propranolol; Randomized Controlled Trials as Topic
PubMed: 18843692
DOI: 10.1002/14651858.CD005508.pub2 -
BMJ Clinical Evidence Aug 2008Pre-eclampsia (raised blood pressure and proteinuria) complicates 2-8% of pregnancies, and raises morbidity and mortality in the mother and child. Pre-eclampsia is more... (Review)
Review
INTRODUCTION
Pre-eclampsia (raised blood pressure and proteinuria) complicates 2-8% of pregnancies, and raises morbidity and mortality in the mother and child. Pre-eclampsia is more common in women with multiple pregnancy and in those who have conditions associates with microvascular disease.
METHODS AND OUTCOMES
We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of preventive interventions in women at risk of pre-eclampsia? What are the effects of interventions in women who develop mild-moderate hypertension during pregnancy? What are the effects of interventions in women who develop severe pre-eclampsia or very high blood pressure during pregnancy? What is the best choice of anticonvulsant for women with eclampsia? We searched: Medline, Embase, The Cochrane Library, and other important databases up to June 2007 (BMJ Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA).
RESULTS
We found 53 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions.
CONCLUSIONS
In this systematic review we present information relating to the effectiveness and safety of the following interventions: anticonvulsants, antihypertensive drugs, antioxidants, antiplatelet drugs, atenolol, bed rest, hospital admission or day care, calcium supplementation, choice of analgesia during labour, early delivery (interventionist care), evening primrose oil, fish oil, glyceryl trinitrate, magnesium supplementation, plasma volume expansion, and salt restriction.
Topics: Anticonvulsants; Antihypertensive Agents; Antioxidants; Eclampsia; Female; Humans; Hypertension; Pre-Eclampsia; Pregnancy
PubMed: 19445808
DOI: No ID Found