Márcio Barra

Non-vitamin K antagonist oral anticoagulants and major bleeding-related fatality in patients with atrial fibrillation and venous thromboembolism: a systematic review and meta-analysis

Objective Non-vitamin K antagonist oral anticoagulants (NOACs) are efficacious and safe antithrombotic drugs but the non-availability of an antidote for potential fatal haemorrhagic events is clinically perceived as a strong limitation. We aimed at evaluating the risk of haemorrhage-related fatalities associated with NOACs in patients requiring long-term anticoagulation. Methods MEDLINE, Cochrane Library and Web of Science databases were searched in November 2014 for atrial fibrillation (AF) or venous thromboembolism (VTE) phase III randomised controlled trials (RCT) comparing NOACs with vitamin K antagonists (VKAs) or low molecular weight heparin (LMWH) followed by VKAs. Pooled OR and 95% CIs were estimated through meta-analysis. Heterogeneity was assessed with the I2 test. Results Eleven studies were included: 5 on AF and 6 on VTE. A total of 100 324 patients were evaluated in 4 rivaroxaban, 3 dabigatran, 2 apixaban and 2 edoxaban studies. NOAC-treated patients had a 47% odds reduction compared with VKA (OR 0.53; 95% CI 0.42 to 0.68; I2=0%; 3 events avoided per 1000 patients) and 64% odds reduction compared with LMWH–VKA (OR 0.36; 95% CI 0.15 to 0.84; I2=0%; 1 event avoided per 1000 patients) regarding fatal bleeding risk. Case fatality due to major bleeding was lower in NOAC-treated patients both in AF (OR 0.68; 95% CI 0.48 to 0.96; I2=37%; 1 death avoided per 39 major bleedings) and VTE (OR 0.54; 95% CI 0.22 to 1.32; I2=0%) patients. AF survivors of major bleeding events treated with NOACs had lower mortality compared with patients treated with VKAs (OR 0.57; 95% CI 0.45 to 0.73; I2=0%; 78 events avoided per 1000 survivors to major bleeding). Conclusions These data suggest that NOACs decrease the risk of fatality cases related to major bleeding events, particularly in AF patients. These results support the safety profile of NOACs even without having a widely available drug-specific antidote.

Risk of drug-induced liver injury with the new oral anticoagulants: systematic review and meta-analysis

Objective In recent years, safety alerts have been made warning of the risk of serious drug-induced liver injury (DILI) caused by cardiovascular drugs. The new oral anticoagulants (NOACs) have now reached the market. However, safety concerns have been raised about their hepatic safety. Therefore we aimed to evaluate NOAC liver-related safety. Methods Systematic review and meta-analysis of phase III randomised controlled trials (RCTs). Medline and CENTRAL were searched to September 2013. Reviews and reference lists were also searched. Two reviewers independently searched for studies and retrieved data estimates. Primary outcome was DILI (transaminases elevations >3× upper limit of normal (ULN) with total bilirubin >2× ULN). NOACs were compared against any control group. Random-effects meta-analysis was performed, and pooled estimates were expressed as relative risk (RR) and 95% CI heterogeneity was evaluated with I2 test. Results Twenty-nine RCTs evaluating 152 116 patients (mean follow-up of 16 months) were included. All RCTs were rated as having low risk of bias. NOAC were not associated with an increased risk of DILI (RR 0.90, 95% CI 0.72 to 1.13, I2=0%). Similar results were obtained for individual NOAC (rivaroxaban, apixaban, dabigatran, darexaban, edoxaban) and considering the different control groups (vitamin K antagonists, low molecular weight heparin (LMWH) and placebo). The risk of transaminases elevations (>3×ULN) was lower among NOAC-treated patients, in particular in comparison with LMWH-treated patients (RR 0.71, 95% CI 0.59 to 0.85; I2=27%) Conclusions NOACs are not associated with an increased risk of DILI. The unexpected ‘protective’ effect of NOAC is probably due to LMWH-associated hepatotoxicity.

Systematic review with meta‐analysis: the risk of major gastrointestinal bleeding with non‐vitamin K antagonist oral anticoagulants

Gastrointestinal (GI) bleeding is a common complication among anticoagulated patients. Non‐vitamin K antagonist oral anticoagulants (NOACs) are associated with increased risk of GI (major and clinically relevant non‐major) bleeding. However, more information is needed regarding severe events.

Risk of Substantial Intraocular Bleeding With Novel Oral Anticoagulants: Systematic Review and Meta-analysis

IMPORTANCE In noninferiority trials, novel oral anticoagulants (NOACs), also known as non-vitamin K oral anticoagulants, were at least noninferior to standard care in the prevention of most prothrombotic conditions. However, differences exist in the safety profile of antithrombotic drugs, and little is known about their intraocular bleeding risk. OBJECTIVE To evaluate the risk of substantial intraocular bleeding associated with NOACs. DATA SOURCES MEDLINE, Cochrane Library, SciELO collection, and Web of Science databases were searched from inception to November 2014, as well as other systematic reviews and regulatory agencies documentation. STUDY SELECTION All phase 3 randomized clinical trials (RCTs) comparing NOACs with any other control that reported intraocular bleeding events. DATA EXTRACTION AND SYNTHESIS Data were extracted independently by 2 of the authors and pooled using random-effects meta-analysis. Heterogeneity was assessed with the I2 test. MAIN OUTCOMES AND MEASURES Substantial intraocular bleeding was evaluated with pooled risk ratios (RRs) and 95% CIs. RESULTS Seventeen RCTs were included. In patients with atrial fibrillation, no difference was identified between NOACs and vitamin K antagonists (RR, 0.84; 95% CI, 0.59-1.19; I2 = 35%; 5 RCTs), and no increased risk was identified compared with acetylsalicylic acid (RR, 14.96; 95% CI, 0.85-262.00; 1 RCT). In patients with venous thromboembolism, no increased risk of substantial intraocular bleeding compared with sequential treatment with low-molecular-weight heparin and a vitamin K antagonist (RR, 0.67; 95% CI, 0.37-1.20; I2 = 0%; 5 RCTs) was identified. Regarding patients who underwent orthopedic surgery, the risk was not different between NOACs and low-molecular-weight heparin (RR, 2.13; 95% CI, 0.22-20.50; I2 = 0%; 5 RCTs). CONCLUSIONS AND RELEVANCE Randomized data suggest that no differences exist in the risk of substantial intraocular bleeding between NOACs and other antithrombotic drugs. However, the number of events was scarce so that additional studies from larger databases that monitor patients under conditions of ophthalmologic routine clinical practice should be performed to better characterize the safety profile of NOACs.

Espresso Coffee for the Treatment of Somnolence in Parkinson's Disease: Results of n-of-1 Trials.

There is limited information available concerning the treatment of daytime somnolence associated with Parkinson’s disease (PD); the most frequently applied therapeutic strategies include decreasing the dose of dopamine agonists or adding potential wake-promoting agents. There is recent data from a placebo-controlled trial concluding on a non-significant trend in favor of caffeine. We aimed to evaluate the efficacy of espresso-coffee in the treatment of daytime somnolence in PD. To evaluate the efficacy of espresso-coffee in the treatment of daytime somnolence in PD, we have conducted multiple single-patient (n-of-1) clinical trials comparing regular espresso coffee to decaffeinated coffee in PD patients presenting moderate to severe daytime somnolence defined as an Epworth Sleepiness Scale score >9. Each single-patient (n-of-1) trial included a sequence of three crossovers (two treatment periods separated by two days of washout). Four patients were included in the studies and three completed the three pairs of treatment periods. In two of the four patients, espresso coffee was considered beneficial. This study concludes that multiple single patient trials are feasible in PD and suggests that espresso-coffee may have a beneficial effect on daytime somnolence in some patients. These results cannot be generalized beyond the patients included in these trials.

How safe is acetaminophen use in patients treated with vitamin K antagonists? A systematic review and meta-analysis

INTRODUCTION Acetaminophen is a commonly prescribed and over-the-count used drug, and is considered to be the preferred treatment choice for anticoagulated patients requiring analgesic drug therapy. However, observational data have suggested that this drug combination may increase the International Normalized Ratio (INR) values and bleeding events in patients taking Vitamin K antagonists (VKAs). Still, the clinical impact of this putative effect remains unknown. Therefore, we performed a systematic review of randomized controlled trials (RCTs) to estimate the impact of concomitant use of acetaminophen and VKA in the INR measurements METHODS Systematic review and meta-analysis of RCTs comparing acetaminophen versus placebo or no treatment, in VKA-treated patients and reporting INR estimates. Medline and Cochrane Library were searched up to April 2014. Primary outcome was the mean difference (MD) between the greatest INR elevations in each treatment arm. Random-effects meta-analysis was performed to derive pooled estimates and 95% Confidence Interval (CI). Heterogeneity was evaluated with I(2) test. RESULTS Seven RCTs (n=225 patients) were included. Acetaminophen was associated with a mean 0.62 INR increase (95%CI: 0.46 to 0.78; I(2)=25%) compared to placebo in VKA-treated patients. Studies did not report any major bleeding event. Meta-regression showed a significant 0.17 mean increase of the INR per each daily gram of acetaminophen (95%CI: 0.004 to 0.33). CONCLUSION Acetaminophen is associated with a statistically significant and possible clinically relevant increase in the INR, with a dose dependent relationship. Patients treated concomitantly with VKA and acetaminophen should be monitored more regularly for possible VKA dosage adjustment.

Pericardial bleeding risk with non-vitamin K oral anticoagulants: A meta-analysis

a Clinical Pharmacology Unit, Instituto de Medicina Molecular, Lisbon, Portugal b Laboratory of Clinical Pharmacology, Faculty of Medicine, University of Lisbon, Portugal c Cardiology Department, Hospital Garcia de Orta, Almada, Portugal d Cardiology Department, CCUL, CAML, Faculty of Medicine, Lisbon, Portugal e Portuguese Collaborating Centre of the Cochrane Iberoamerican Network, Faculty of Medicine, University of Lisbon, Portugal f Evidence Based Medicine Centre, Faculty of Medicine, University of Lisbon, Portugal

Risk of insomnia with non-vitamin K oral anticoagulants: systematic review and meta-analysis

PurposeInsomnia is an important adverse event of mechanical thromboprophylaxis. This sleep disorder has been reported as one of the commonest adverse events of the new oral anti-Xa anticoagulant darexaban, with similar rates to mechanical thromboprophylaxis in a randomized controlled trial (RCT). However, the perceived effect could have been biased because it was an open-label RCT. Therefore, we aimed to review the incidence of insomnia with non-vitamin K antagonist oral anticoagulants (NOACs).MethodsWe performed a systematic review and meta-analysis of Phase III RCTs. Electronic databases MEDLINE and CENTRAL (inception to September 2013) were searched as well as review articles and references of included studies.We included phase III RCTs which compared NOACs with any other control group. Data were analyzed and pooled to estimate risk ratio (RR) with 95% confidence intervals (95%CI) for insomnia using inverse variance method. Statistical heterogeneity was evaluated with I2 test.ResultsWe included seven studies (two apixaban RCTs, two dabigatran RCTs, one darexaban RCTs, and two rivaroxaban RCTs), enrolling a total of 23,023 patients. Overall, NOACs were not associated to an increased risk of insomnia: RR 0.94 (95%CI 0.83–1.08; I2 = 0%). In blinded studies (six studies), NOACs also did not show increased risk of insomnia (RR 0.94, 95%CI 0.83–1.08; I2 = 0%). Results were similar irrespective of the comparators.ConclusionsNOACs (apixaban, dabigatran, darexaban, rivaroxaban) did not show increased risk of insomnia. Results according to study design (blinded vs. open-label trials) overlap the main analysis.

Prevalência da anticoagulação oral em doentes com fibrilhação auricular em Portugal: revisão sistemática e meta‐análise de estudos observacionais

INTRODUCTION AND OBJECTIVES Oral anticoagulation (OAC) is an effective treatment in the prevention of thromboembolic events in patients with atrial fibrillation (AF). The aim of this review was to estimate the prevalence of OAC therapy in patients with AF in Portugal. METHODS MEDLINE, the Index of Portuguese Medical Journals and SIBUL (the Bibliographic Catalog of the Integrated Library System of the University of Lisbon) were searched for Portuguese observational studies reporting the proportion of anticoagulated patients with AF. The pooled estimated prevalence of anticoagulated patients and respective 95% confidence interval (CI) were determined by means of a meta-analysis. RESULTS Seven studies were included for analysis, of which four were conducted in a hospital environment and three in the general community. These studies enrolled a total of 891 patients with AF. The pooled estimated prevalence of anticoagulated patients was 40% (95% CI: 32-48%). CONCLUSIONS The prevalence of OAC in Portuguese AF patients is low. There is a need to promote change in OAC prescribing habits for AF patients in Portugal, in accordance with international guidelines.