Indefinite Anticoagulant Therapy for First Unprovoked Venous Thromboembolism
Bibliographic record
Abstract
BACKGROUND: Clinical practice guidelines recommend indefinite anticoagulation for a first unprovoked venous thromboembolism (VTE). OBJECTIVE: To estimate the benefit-harm tradeoffs of indefinite anticoagulation in patients with a first unprovoked VTE. DESIGN: Markov modeling study. DATA SOURCES: Systematic reviews and meta-analyses for the long-term risks and case-fatality rates of recurrent VTE and major bleeding. Published literature for costs, quality of life, and other clinical events. TARGET POPULATION: Patients with a first unprovoked VTE who have completed 3 to 6 months of initial anticoagulant treatment. TIME HORIZON: Lifetime. PERSPECTIVE: Canadian health care public payer. INTERVENTION: Indefinite anticoagulation with direct oral anticoagulants. OUTCOME MEASURES: Recurrent VTE events, major bleeding events, costs in 2022 Canadian dollars (CAD), and quality-adjusted life-years (QALYs). RESULTS OF BASE-CASE ANALYSIS: When compared with discontinuing anticoagulation after initial treatment in a hypothetical cohort of 1000 patients aged 55 years, indefinite anticoagulation prevented 368 recurrent VTE events, which included 14 fatal pulmonary emboli, but induced an additional 114 major bleeding events, which included 30 intracranial hemorrhages and 11 deaths from bleeding. Indefinite anticoagulation cost CAD $16 014 more per person and did not increase QALYs (-0.075 per person). RESULTS OF SENSITIVITY ANALYSIS: Model results were most sensitive to the case-fatality rate of major bleeding and the annual risk for major bleeding during extended anticoagulation. LIMITATION: The model assumed that risks for recurrent VTE and major bleeding measured in clinical trials at 1 year remained constant during extended anticoagulation. CONCLUSION: Clinicians should use shared decision making to incorporate individual patient preferences and values when considering treatment duration for unprovoked VTE. PRIMARY FUNDING SOURCE: Canadian Institutes of Health Research.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.009 | 0.037 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.002 | 0.004 |
| Bibliometrics | 0.001 | 0.002 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.004 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".