Dataset Information

Anticoagulation intensity and outcomes among patients prescribed oral anticoagulant therapy: a systematic review and meta-analysis.

ABSTRACT: BACKGROUND: Patients taking oral anticoagulant therapy balance the risks of hemorrhage and thromboembolism. We sought to determine the association between anticoagulation intensity and the risk of hemorrhagic and thromboembolic events. We also sought to determine how under-or overanticoagulation would influence patient outcomes. METHODS: We reviewed the MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials and CINAHL databases to identify studies involving patients taking anticoagulants that reported person-years of observation and the number of hemorrhages or thromboemboli in 3 or more discrete ranges of international normalized ratios. We estimated the overall relative and absolute risks of events specific to anticoagulation intensity. RESULTS: We included 19 studies. The risk of hemorrhage increased significantly at high international normalized ratios. Compared with the therapeutic ratio of 2-3, the relative risk (RR) of hemorrhage (and 95% confidence intervals [CIs]) were 2.7 (1.8-3.9; p < 0.01) at a ratio of 3-5 and 21.8 (12.1-39.4; p < 0.01) at a ratio greater than 5. The risk of thromboemboli increased significantly at ratios less than 2, with a relative risk of 3.5 (95% CI 2.8-4.4; p < 0.01). The risk of hemorrhagic or thromboembolic events was lower at ratios of 3-5 (RR 1.8, 95% CI 1.2-2.6) than at ratios of less than 2 (RR 2.4, 95% CI 1.9-3.1; p = 0.10). We found that a ratio of 2-3 had the lowest absolute risk (AR) of events (AR 4.3%/yr, 95% CI 3.0%-6.3%). CONCLUSIONS: The risks of hemorrhage and thromboemboli are minimized at international normalized ratios of 2-3. Ratios that are moderately higher than this therapeutic range appear safe and more effective than subtherapeutic ratios.

SUBMITTER: Oake N

PROVIDER: S-EPMC2474869 | biostudies-other | 2008 Jul

REPOSITORIES: biostudies-other

ACCESS DATA

Publications

Anticoagulation intensity and outcomes among patients prescribed oral anticoagulant therapy: a systematic review and meta-analysis.

Oake Natalie N Jennings Alison A Forster Alan J AJ Fergusson Dean D Doucette Steve S van Walraven Carl C

CMAJ : Canadian Medical Association journal = journal de l'Association medicale canadienne 20080701 3

<h4>Background</h4>Patients taking oral anticoagulant therapy balance the risks of hemorrhage and thromboembolism. We sought to determine the association between anticoagulation intensity and the risk of hemorrhagic and thromboembolic events. We also sought to determine how under-or overanticoagulation would influence patient outcomes.<h4>Methods</h4>We reviewed the MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials and CINAHL databases to identify studies involving patients taking ...[more]

PMID: 18663203

Similar Datasets

Project description:BackgroundPost-operative atrial fibrillation (POAF) is the most common complication after cardiac surgery. Recent studies had shown this phenomenon is no longer considered transitory and is associated with higher risk of thromboembolic events or death. The aim of this study was to systematically review and analyze previous studies comparing oral anticoagulation therapy with no anticoagulation, regarding these long-term outcomes.MethodsPubMed/MEDLINE, EMBASE, Web of Science and Cochrane Database were systematically searched to identify the studies comparing the risk of stroke, or thromboembolic events or mortality of POAF patients who received anticoagulation compared with those who were not anticoagulated. Incidence of stroke, thromboembolic events and all-cause mortality were evaluated up to 10 years after surgery. Time-to-event outcomes were collected through hazard ratio (HR) along with their variance and the early endpoints using frequencies or odds ratio (OR). Random effect models were used to compute statistical combined measures and 95% confidence intervals (CI). Heterogeneity was evaluated through Q statistic-related measures of variance (Tau2, I2, Chi-squared test).ResultsEight observational cohort studies were selected, including 15,335 patients (3492 on Oral Anticoagulants (OAC) vs 11,429 without OAC) that met the inclusion criteria for qualitative synthesis. Patients had a wide gender distribution (38.6-82.3%), each study with a mean age above 65 years (67.5-85). Vitamin K antagonists were commonly prescribed anticoagulants (74.3-100%). OAC was associated with a protective impact on all-cause mortality at a mean of 5.0 years of follow-up (HR is 0.85 [0.72-1.01]; p = 0.07; I2 = 48%). Thromboembolic events did not differ between the two treatment arms (HR 0.68 [0.40-1.15], p = 0.15).ConclusionCurrent literature suggests a possibly protective impact of OAC therapy for all-cause mortality in patients with new-onset atrial fibrillation after cardiac surgery. However, it does not appear to impact thromboembolism rate.

Dataset Information

Anticoagulation intensity and outcomes among patients prescribed oral anticoagulant therapy: a systematic review and meta-analysis.

Publications

Anticoagulation intensity and outcomes among patients prescribed oral anticoagulant therapy: a systematic review and meta-analysis.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets