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Lancet (London, England) Jan 2012Uptake of self-testing and self-management of oral anticoagulation [corrected] has remained inconsistent, despite good evidence of their effectiveness. To clarify the... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Uptake of self-testing and self-management of oral anticoagulation [corrected] has remained inconsistent, despite good evidence of their effectiveness. To clarify the value of self-monitoring of oral anticoagulation, we did a meta-analysis of individual patient data addressing several important gaps in the evidence, including an estimate of the effect on time to death, first major haemorrhage, and thromboembolism.
METHODS
We searched Ovid versions of Embase (1980-2009) and Medline (1966-2009), limiting searches to randomised trials with a maximally sensitive strategy. We approached all authors of included trials and requested individual patient data: primary outcomes were time to death, first major haemorrhage, and first thromboembolic event. We did prespecified subgroup analyses according to age, type of control-group care (anticoagulation-clinic care vs primary care), self-testing alone versus self-management, and sex. We analysed patients with mechanical heart valves or atrial fibrillation separately. We used a random-effect model method to calculate pooled hazard ratios and did tests for interaction and heterogeneity, and calculated a time-specific number needed to treat.
FINDINGS
Of 1357 abstracts, we included 11 trials with data for 6417 participants and 12,800 person-years of follow-up. We reported a significant reduction in thromboembolic events in the self-monitoring group (hazard ratio 0·51; 95% CI 0·31-0·85) but not for major haemorrhagic events (0·88, 0·74-1·06) or death (0·82, 0·62-1·09). Participants younger than 55 years showed a striking reduction in thrombotic events (hazard ratio 0·33, 95% CI 0·17-0·66), as did participants with mechanical heart valve (0·52, 0·35-0·77). Analysis of major outcomes in the very elderly (age ≥85 years, n=99) showed no significant adverse effects of the intervention for all outcomes.
INTERPRETATION
Our analysis showed that self-monitoring and self-management of oral coagulation is a safe option for suitable patients of all ages. Patients should also be offered the option to self-manage their disease with suitable health-care support as back-up.
FUNDING
UK National Institute for Health Research (NIHR) Technology Assessment Programme, UK NIHR National School for Primary Care Research.
Topics: Administration, Oral; Anticoagulants; Drug Monitoring; Hemorrhage; Humans; International Normalized Ratio; Self Care; Thromboembolism; Vitamin K
PubMed: 22137798
DOI: 10.1016/S0140-6736(11)61294-4 -
European Heart Journal May 2017To review maternal and foetal outcomes in women with mechanical heart valves (MHVs) treated with vitamin-K antagonists (VKAs), first-trimester heparin followed by VKAs... (Meta-Analysis)
Meta-Analysis Review
AIMS
To review maternal and foetal outcomes in women with mechanical heart valves (MHVs) treated with vitamin-K antagonists (VKAs), first-trimester heparin followed by VKAs (sequential treatment), low molecular weight heparin (LMWH) and unfractionated heparin (UFH) during pregnancy, in order to inform practice.
METHODS AND RESULTS
Medline, Embase and Central were searched from inception until February 2016. Two reviewers independently screened 1786 titles, reviewed 110 full-texts and extracted data and assessed risk-of-bias from 46 articles. Pooled incidence (95% confidence intervals) was calculated for maternal and foetal outcomes. Included studies had a moderate or high risk-of-bias. With VKAs, sequential treatment and LMWH, maternal mortality occurred in 0.9% (0.4-1.4), 2.0% (0.8-3.1) and 2.9% (0.2-5.7), thromboembolic complications in 2.7% (1.4-4.0), 5.8% (3.8-7.7) and 8.7% (3.9-13.4), livebirths in 64.5% (48.8-80.2), 79.9% (74.3-85.6) and 92.0% (86.1-98.0) and anticoagulant-related foetal/neonatal adverse events (embryopathy or foetopathy) in 2.0% (0.3-3.7), 1.4% (0.3-2.5) and 0%, respectively. When UFH is used throughout pregnancy, 11.2% (2.8-19.6) suffered thromboembolic complications. Foetal loss and adverse events occurred with first-trimester warfarin doses ≤ 5 mg/day, although there were more livebirths [83.6% (75.8-91.4) vs. 43.9% (32.8-55.0)] and fewer foetal anomalies [2.3% (0.7-4.0) vs. 12.4% (3.3-21.6)] with lower doses than with warfarin > 5 mg/day.
CONCLUSIONS
VKAs are associated with fewest maternal complications but also with fewest livebirths. Sequential treatment does not eliminate anticoagulant-related foetal/neonatal adverse events. LMWH is associated with the highest number of livebirths. The safety of UFH throughout pregnancy and first-trimester warfarin ≤ 5 mg/day remains unconfirmed.
Topics: Anticoagulants; Female; Fetal Death; Fetal Diseases; Heart Valve Prosthesis; Heparin; Heparin, Low-Molecular-Weight; Humans; Incidence; Maternal Mortality; Pregnancy; Pregnancy Complications, Cardiovascular; Pregnancy Outcome; Pregnancy Trimester, First; Thromboembolism; Vitamin K; Warfarin
PubMed: 28329059
DOI: 10.1093/eurheartj/ehx032 -
BMJ (Clinical Research Ed.) Aug 2013To summarise and compare the efficacy and safety of various oral anticoagulants (dabigatran, rivaroxaban, apixaban, and vitamin K antagonists) and antiplatelet agents... (Meta-Analysis)
Meta-Analysis Review
Efficacy and safety outcomes of oral anticoagulants and antiplatelet drugs in the secondary prevention of venous thromboembolism: systematic review and network meta-analysis.
OBJECTIVE
To summarise and compare the efficacy and safety of various oral anticoagulants (dabigatran, rivaroxaban, apixaban, and vitamin K antagonists) and antiplatelet agents (acetylsalicylic acid) for the secondary prevention of venous thromboembolism.
DESIGN
Systematic review and network meta-analysis.
DATA SOURCES
Literature search using Medline (1950 to present), Embase (1980 to present), and the Cochrane Register of Controlled Trials using the OVID interface. Publications from potentially relevant journals were also searched by hand.
REVIEW METHODS
Randomised controlled trials of patients receiving anticoagulants, antiplatelet drugs, or placebo or observation for secondary prevention of venous thromboembolism. Selected outcomes were rates of recurrent venous thromboembolism and major bleeding. Two reviewers independently extracted data onto standardised forms.
RESULTS
12 articles met our inclusion criteria, with 11,999 patients evaluated for efficacy and 12,167 for safety. All treatments reduced the risk of recurrent venous thromboembolism. Compared with placebo or observation, vitamin K antagonists at a standard adjusted dose (target international normalised ratio 2.0-3.0) showed the highest risk difference (odds ratio 0.07; 95% credible interval 0.03 to 0.15) and acetylsalicylic acid showed the lowest risk difference (0.65; 0.39 to 1.03). Risk of major bleeding was higher with a standard adjusted dose of vitamin K antagonists (5.24; 1.78 to 18.25) than with placebo or observation. Fatal recurrent venous thromboembolism and fatal bleeding were rare. Detailed subgroup and individual patient level data were not available.
CONCLUSIONS
All oral anticoagulants and antiplatelet agents investigated in this analysis were associated with a reduced recurrence of venous thromboembolism compared with placebo or observation, although acetylsalicylic acid was associated with the lowest risk reduction. Vitamin K antagonists given at a standard adjusted dose was associated with the greatest risk reduction in recurrent venous thromboembolism, but also the greatest risk of major bleeding.
Topics: Anticoagulants; Aspirin; Benzimidazoles; Dabigatran; Hemorrhage; Humans; Morpholines; Platelet Aggregation Inhibitors; Pyrazoles; Pyridones; Recurrence; Rivaroxaban; Thiophenes; Venous Thromboembolism; Vitamin K; beta-Alanine
PubMed: 23996149
DOI: 10.1136/bmj.f5133 -
Journal of the American Society of... Mar 2014Novel oral anticoagulants (NOACs) (rivaroxaban, dabigatran, apixaban) have been approved by international regulatory agencies to treat atrial fibrillation and venous... (Comparative Study)
Comparative Study Review
Novel oral anticoagulants (NOACs) (rivaroxaban, dabigatran, apixaban) have been approved by international regulatory agencies to treat atrial fibrillation and venous thromboembolism in patients with kidney dysfunction. However, altered metabolism of these drugs in the setting of impaired kidney function may subject patients with CKD to alterations in their efficacy and a higher risk of bleeding. This article examined the efficacy and safety of the NOACs versus vitamin K antagonists (VKAs) for atrial fibrillation and venous thromboembolism in patients with CKD. A systematic review and meta-analyses of randomized controlled trials were conducted to estimate relative risk (RR) with 95% confidence interval (95% CIs) using a random-effects model. MEDLINE, Embase, and the Cochrane Library were searched to identify articles published up to March 2013. We selected published randomized controlled trials of NOACs compared with VKAs of at least 4 weeks' duration that enrolled patients with CKD (defined as creatinine clearance of 30-50 ml/min) and reported data on comparative efficacy and bleeding events. Eight randomized controlled trials were eligible. There was no significant difference in the primary efficacy outcomes of stroke and systemic thromboembolism (four trials, 9693 participants; RR, 0.64 [95% CI, 0.39 to 1.04]) and recurrent thromboembolism or thromboembolism-related death (four trials, 891 participants; RR, 0.97 [95% CI, 0.43 to 2.15]) with NOACs versus VKAs. The risk of major bleeding or the combined endpoint of major bleeding or clinically relevant nonmajor bleeding (primary safety outcome) (eight trials, 10,616 participants; RR 0.89 [95% CI, 0.68 to 1.16]) was similar between the groups. The use of NOACs in select patients with CKD demonstrates efficacy and safety similar to those with VKAs. Proactive postmarketing surveillance and further studies are pivotal to further define the rational use of these agents.
Topics: Administration, Oral; Anticoagulants; Atrial Fibrillation; Hemorrhage; Humans; Randomized Controlled Trials as Topic; Renal Insufficiency, Chronic; Venous Thromboembolism; Vitamin K
PubMed: 24385595
DOI: 10.1681/ASN.2013040361 -
The Cochrane Database of Systematic... Jun 2011Cancer increases the risk of thromboembolic events even while on anticoagulation. (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Cancer increases the risk of thromboembolic events even while on anticoagulation.
OBJECTIVES
To compare the efficacy and safety of low molecular weight heparin (LMWH) and oral anticoagulants for the long-term treatment of venous thromboembolism (VTE) in patients with cancer.
SEARCH STRATEGY
A comprehensive search for studies of anticoagulation in cancer patients including a February 2010 electronic search of: the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE and ISI Web of Science.
SELECTION CRITERIA
Randomized controlled trials (RCTs) comparing long-term treatment with LMWH versus oral anticoagulants (vitamin K antagonist (VKA) or ximelagatran) in patients with cancer and symptomatic objectively-confirmed VTE.
DATA COLLECTION AND ANALYSIS
Using a standardized data form we extracted data on methodological quality, participants, interventions and outcomes of interest: survival, recurrent VTE, major bleeding, minor bleeding, thrombocytopenia and postphlebitic syndrome. We assessed the quality of evidence at the outcome level following the GRADE approach.
MAIN RESULTS
Of 8187 identified citations, nine RCTs were eligible and reported data for 1908 patients with cancer. Meta-analysis of seven RCTs showed that LMWH, compared to VKA provided no statistically significant survival benefit (hazard ratio (HR) 0.96; 95% confidence interval (CI) 0.81 to 1.14) but a statistically significant reduction in VTE (HR 0.47; 95% CI 0.32 to 0.71). Other results did not exclude a beneficial or harmful effect of LMWH compared to VKA for the outcomes of major bleeding (RR 1.05; 95% CI 0.53 to 2.10) or thrombocytopenia (RR 1.02; 95% CI 0.60 to 1.74). The quality of evidence was low for mortality, major bleeding and minor bleeding and moderate for recurrent VTE. One RCT comparing six months extension of anticoagulation with 18 months ximelagatran 24 mg twice daily versus placebo found a reduction in VTE (HR 0.16; 95% CI 0.09 to 0.30) but did not exclude beneficial or harmful effects for the outcomes of mortality and bleeding. One RCT, comparing dabigatran to VKA, did not exclude beneficial or harmful effect of one agent over the other.
AUTHORS' CONCLUSIONS
For the long-term treatment of VTE in patients with cancer, LMWH compared to VKA reduces venous thromboembolic events but not death. The decision for a patient with cancer and VTE to start long-term LMWH versus oral anticoagulation should balance the benefits and downsides and integrate the patient's values and preferences for the important outcomes and alternative management strategies.
Topics: Anticoagulants; Azetidines; Benzylamines; Heparin, Low-Molecular-Weight; Humans; Neoplasms; Randomized Controlled Trials as Topic; Venous Thromboembolism; Vitamin K
PubMed: 21678361
DOI: 10.1002/14651858.CD006650.pub3 -
Journal of Thrombosis and Thrombolysis Jul 2017Prothrombin complex concentrate (PCC) is used for reversal of vitamin K antagonists (VKA) in patients with bleeding complications. This study aims to assess benefits and... (Comparative Study)
Comparative Study Meta-Analysis Review
Prothrombin complex concentrate (PCC) is used for reversal of vitamin K antagonists (VKA) in patients with bleeding complications. This study aims to assess benefits and harms of 4-factor PCC compared to fresh frozen plasma (FFP) or no treatment in VKA associated bleeding. PubMed, EMBASE and CENTRAL were searched from 1945 to August 2015. Studies reporting 4-factor PCC use for VKA associated bleeding and providing data on INR normalization, mortality or thromboembolic (TE) complications were eligible. Two authors screened titles and full articles for inclusion, extracted data, and assessed risk of bias. Mortality data were pooled using Mantel-Haenszel random effects meta-analysis. Nineteen studies were included (N = 2878); 18 cohort studies and one RCT. Six studies had good methodological quality, 9 moderate and 4 poor. Baseline INR values ranged from 2.2 to >20. The INR within 1 h after PCC administration ranged from 1.4 to 1.9, and after FFP administration from 2.2 to 12. PCC reduced the time to reach INR correction in comparison with FFP or no treatment. The observed mortality rate ranged from 0 to 43% (mean 17%) in the PCC, 4.8-54% (mean 16%) in the FFP and 23-69% (mean 51%) in the no treatment group. Meta-analysis of mortality data resulted in an OR of 0.64 (95% confidence interval [CI] 0.27-1.5) for PCC versus FFP and an OR 0.41 (95% CI 0.13-1.3) for PCC versus no treatment. TE complications were observed in 0-18% (mean 2.5%) of PCC and in 6.4% of FFP recipients. Four-factor PCC is an effective and safe option in reversal of VKA bleeding events.
Topics: Anticoagulants; Blood Coagulation Factors; Hemorrhage; Humans; International Normalized Ratio; Plasma; Vitamin K
PubMed: 28540468
DOI: 10.1007/s11239-017-1506-0 -
The Cochrane Database of Systematic... Sep 2015A deficiency in vitamin K has been associated with increased calcium deposition and coronary artery calcification, which may lead to cardiovascular disease. (Review)
Review
BACKGROUND
A deficiency in vitamin K has been associated with increased calcium deposition and coronary artery calcification, which may lead to cardiovascular disease.
OBJECTIVES
To determine the effectiveness of vitamin K supplementation as a single nutrient supplement for the primary prevention of cardiovascular disease.
SEARCH METHODS
We searched the following electronic databases: the Cochrane Central Register of Controlled Trials (CENTRAL, Issue 8 of 12, 2014); MEDLINE (Ovid, 1946 to September week 2 2014); EMBASE Classic + EMBASE (Ovid, 1947 to September 18 2014); Science Citation Index Expanded (SCI-EXPANDED) and Conference Proceedings Citation Index, Science (CPCI-S) (both 1990 to 17 September 2014) on Web of Science (Thomson Reuters); Database of Abstracts of Reviews of Effects (DARE); Health Technology Assessment Database and Health Economics Evaluations Database (Issue 3 of 4, 2014). We searched trial registers and reference lists of reviews for further studies. We applied no language restrictions.
SELECTION CRITERIA
We included randomised controlled trials of vitamin K supplementation as a single nutrient supplement, lasting at least three months, and involving healthy adults or adults at high risk of cardiovascular disease. The comparison group was no intervention or placebo. The outcomes of interest were cardiovascular disease clinical events and cardiovascular disease risk factors.
DATA COLLECTION AND ANALYSIS
Two review authors independently selected trials for inclusion, abstracted the data and assessed the risk of bias.
MAIN RESULTS
We included only one small trial (60 participants randomised) which overall was judged to be at low risk of bias. The study examined two doses of menaquinone (vitamin K2) over 3 months in healthy participants aged 40 to 65 years. The primary focus of the trial was to examine the effects of menaquinone (subtype MK7) on different matrix Gla proteins (MGP - vitamin K dependent proteins in the vessel wall) at different doses, but the authors also reported blood pressure and lipid levels. The trial did not report on our primary outcomes (cardiovascular disease clinical events) as it was small, short term and conducted in healthy participants.In terms of cardiovascular disease risk factors, no effects were seen for vitamin K2 on blood pressure or lipid levels, although the trial was small and findings are limited. The trial did not report any of our other secondary outcomes.
AUTHORS' CONCLUSIONS
The very limited results of this review highlight the lack of evidence currently available to determine the effectiveness of vitamin K supplementation for the primary prevention of cardiovascular disease, and demonstrate the need for further high quality trials in this area.
Topics: Adult; Antifibrinolytic Agents; Cardiovascular Diseases; Humans; Middle Aged; Primary Prevention; Vitamin K 2
PubMed: 26389791
DOI: 10.1002/14651858.CD011148.pub2 -
Journal of Thrombosis and Thrombolysis Oct 2023Oral anticoagulation significantly reduces the incidence of dementia in atrial fibrillation patients. However, this protective effect has not been compared between... (Meta-Analysis)
Meta-Analysis Review
Oral anticoagulation significantly reduces the incidence of dementia in atrial fibrillation patients. However, this protective effect has not been compared between Direct Oral Anticoagulants (DOAC) and Vitamin K antagonists' anticoagulants (VKA). We conducted an electronic search for potentially eligible studies through the bibliographic databases MEDLINE, CENTRAL, ClinicalTrials.gov, EMBASE and Web of Science. The outcome of interest was dementia. Random-effects meta-analysis was performed. Nine observational studies were included and 1,175,609 atrial fibrillation patients were enrolled. DOAC therapy was associated with a significant reduction when compared with patients under VKA therapy (hazard ratio 0.89; 95% confidence interval 0.80-0.99). The grade of confidence of our results was very low due to the risk of bias. DOAC therapy is associated with a significant decrease in the risk of dementia when compared with VKA therapy. However, the low certainty of the evidence along with the paucityof clinical trials dedicated to answering this important question underscores a need for global clinical research initiatives.
Topics: Humans; Atrial Fibrillation; Anticoagulants; Fibrinolytic Agents; Vitamin K; Dementia; Administration, Oral; Stroke
PubMed: 37405677
DOI: 10.1007/s11239-023-02843-5 -
European Journal of Clinical... Dec 2022This systematic review and meta-analysis aimed to determine whether tramadol intake increases the risk of bleeding in patients receiving oral anticoagulants. (Meta-Analysis)
Meta-Analysis Review
PURPOSE
This systematic review and meta-analysis aimed to determine whether tramadol intake increases the risk of bleeding in patients receiving oral anticoagulants.
METHODS
This systematic review was registered on PROSPERO, CRD42022327230. We searched PubMed and Embase up to 14 April 2022, and references and citations of included studies were screened. Comparative and non-comparative studies exploring bleeding complications among adult patients on oral anticoagulants and tramadol were included. Risk of bias was assessed using an adaptation of the Drug Interaction Probability Scale for case reports and case series and the Newcastle-Ottawa Scale for comparative studies. A meta-analysis was performed for the risk of serious bleeding (leading to hospitalisation or death) associated with tramadol in patients on vitamin K antagonists.
RESULTS
A total of 17 studies were included: 1 case series, 12 case reports, 2 case-control studies and 2 cohort studies. Most of the studies described tramadol-vitamin K antagonists' concomitant use; one case-control study also assessed dabigatran and rivaroxaban; one case report involved dabigatran. Among case reports/series, a total of 33 patients had a bleeding complication while using tramadol and an oral anticoagulant. The 4 comparative studies reported an increased bleeding risk during tramadol and vitamin K antagonist intake which was statistically significant in one study; the pooled risk ratio of serious bleeding was 2.68 [95% CI: 1.45 to 4.96; p < 0.001].
CONCLUSION
This systematic review confirms an association between tramadol use and risk of bleeding in patients on vitamin K antagonists. Evidence is too limited to assess whether this risk extends to patients on direct oral anticoagulants, and further studies are needed.
Topics: Adult; Humans; Dabigatran; Tramadol; Case-Control Studies; Administration, Oral; Anticoagulants; Rivaroxaban; Hemorrhage; Fibrinolytic Agents; Vitamin K; Atrial Fibrillation
PubMed: 36323905
DOI: 10.1007/s00228-022-03411-1 -
Medicine Dec 2016Data regarding the clinical outcomes in patients with atrial fibrillation (AF) receiving dual antiplatelet therapy (DAPT) and an anticoagulant in addition to DAPT... (Comparative Study)
Comparative Study Meta-Analysis Review
Comparing the clinical outcomes in patients with atrial fibrillation receiving dual antiplatelet therapy and patients receiving an addition of an anticoagulant after coronary stent implantation: A systematic review and meta-analysis of observational studies.
BACKGROUND
Data regarding the clinical outcomes in patients with atrial fibrillation (AF) receiving dual antiplatelet therapy (DAPT) and an anticoagulant in addition to DAPT (DAPT + vitamin K antagonist [VKA]) after coronary stent implantation are still controversial. Therefore, in order to solve this issue, we aim to compare the adverse clinical outcomes in AF patients receiving DAPT and DAPT + VKA after percutaneous coronary intervention and stenting (PCI-S).
METHODS
Observational studies comparing the adverse clinical outcomes such as major bleeding, major adverse cardiovascular events, stroke, myocardial infarction, all-cause mortality, and stent thrombosis (ST) in AF patients receiving DAPT + VKA therapy, and DAPT after PCI-S have been searched from Medline, EMBASE, and PubMed databases. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to express the pooled effect on discontinuous variables, and the pooled analyses were performed with RevMan 5.3.
RESULTS
Eighteen studies consisting of a total of 20,456 patients with AF (7203 patients received DAPT + VKA and 13,253 patients received DAPT after PCI-S) were included in this meta-analysis. At a mean follow-up period of 15 months, the risk of major bleeding was significantly higher in DAPT + VKA group, with OR 0.62 (95% CI 0.50-0.77, P < 0.0001). There was no significant differences in myocardial infarction and major adverse cardiovascular event between DAPT + VKA and DAPT, with OR 1.27 (95% CI 0.92-1.77, P = 0.15) and OR 1.17 (95% CI 0.99-1.39, P = 0.07), respectively. However, the ST, stroke, and all-cause mortality were significantly lower in the DAPT + VKA group, with OR 1.98 (95% CI 1.03-3.81, P = 0.04), 1.59 (95% CI 1.08-2.34, P = 0.02), and 1.41 (95% CI 1.03-1.94, P = 0.03), respectively.
CONCLUSION
At a mean follow-up period of 15 months, DAPT + VKA was associated with significantly lower risk of stroke, ST, and all-cause mortality in AF patients after PCI-S compared with DAPT group. However, the risk of major bleeding was significantly higher in the DAPT + VKA group.
Topics: Anticoagulants; Atrial Fibrillation; Blood Vessel Prosthesis Implantation; Coronary Disease; Drug Therapy, Combination; Humans; Observational Studies as Topic; Percutaneous Coronary Intervention; Platelet Aggregation Inhibitors; Stents; Vitamin K
PubMed: 27977592
DOI: 10.1097/MD.0000000000005581