Evidence map›Paper›PMID 9457092›Full record

Trial reportLancet (London, England)1998

Thrombosis prevention trial: randomised trial of low-intensity oral anticoagulation with warfarin and low-dose aspirin in the primary prevention of ischaemic heart disease in men at increased risk. The Medical Research Council's General Practice Research Framework.

Abstract readClinical TrialComparative StudyRandomized Controlled Trial
PubMed
In one paragraph

Trial report in Lancet (London, England), 1998. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 188 papers, 38 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
188citing papers in PubMed, 38 pooled it
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

188 citing papers in PubMed, 38 syntheses or guidelines pooled it.

  1. Risk of bleeding with concomitant use of oral anticoagulants and aspirin: A systematic review and meta-analysis.American journal of health-system pharmacy : AJHP : official journal of the American Society of Health-System Pharmacists · 2024
    Pooled it
  2. Antiplatelet agents and anticoagulants for hypertension.The Cochrane database of systematic reviews · 2022
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  7. Guideline
  8. Aspirin for primary prevention of stroke in individuals without cardiovascular disease-A meta-analysis.International journal of stroke : official journal of the International Stroke Society · 2020
    Pooled it
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  10. Aspirin Efficacy in Primary Prevention: A Meta-analysis of Randomized Controlled Trials.High blood pressure & cardiovascular prevention : the official journal of the Italian Society of Hypertension · 2019
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  15. Aspirin and the Primary Prevention of Cardiovascular Diseases: An Approach Based on Individualized, Integrated Estimation of Risk.High blood pressure & cardiovascular prevention : the official journal of the Italian Society of Hypertension · 2017
    Guideline
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  18. A systematic review of aspirin in primary prevention: is it time for a new approach?American journal of cardiovascular drugs : drugs, devices, and other interventions · 2015
    Pooled it
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128 more citing papers are in PubMed but not listed here.

4 · The record

Corrections and comments

5 · Who and what money

Authors and funding

0 authors.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundWe aimed to evaluate low intensity oral anticoagulation with warfarin and low-dose aspirin in the primary prevention of ischaemic heart disease (IHD).

methods5499 men aged between 45 years and 69 years at high risk of IHD were recruited from 108 practices in the UK that belong to the Medical Research Council's General Practice Research Framework. Initially, warfarin or placebo was randomly allocated to 1427 men; 1013 of these men later moved to a factorial stage of the trial, retaining their warfarin or placebo warfarin allocation and adding randomly allocated active or placebo aspirin. Another 4072 men entered directly into the factorial stage making a total of 5085 men. The four factorial treatment groups were: active warfarin and active aspirin (WA, n = 1277), active warfarin and placebo aspirin (W, n = 1268), and placebo warfarin and active aspirin (A, n = 1268), and placebo warfarin and placebo aspirin (P, n = 1272). The primary end-point was all IHD defined as the sum of coronary death and fatal and non-fatal myocardial infarction (MI).

findingsThe mean International Normalised Ratio (INR) of those on active warfarin was 1.47. The mean warfarin dose was 4.1 mg a day (range 0.5 mg-12.5 mg). There were 410 IHD events (142 fatal, 268 non-fatal). The main effect of warfarin (i.e., WA and W vs A and P) was a reduction in all IHD of 21% (95% CI 4-35, p = 0.02) chiefly due to a 39% reduction (15-57, p = 0.003) in fatal events so that warfarin reduced the death rate from all causes by 17% (1-30, p = 0.04). The main effect of aspirin (i.e., WA and A vs W and P) was a reduction in all IHD of 20% (1-35, p = 0.04) almost entirely due to a 32% reduction (12-48, p = 0.004) in non-fatal events. Absolute reductions in all IHD due to warfarin or aspirin were 2.6 and 2.3 per 1000 person years, respectively. WA reduced all IHD by 34% (11-51, p = 0.006) compared with P. WA increased haemorrhagic and fatal strokes. Ruptured aortic or dissecting aneurysms occurred in 15 of those who were or had been on warfarin compared with three of those who had not (p = 0.01).

interpretationThese results add to evidence that aspirin reduces non-fatal IHD. Warfarin reduced all IHD chiefly because of an effect on fatal events. Combined treatment with warfarin and aspirin is more effective in the reduction of IHD than either agent on its own.

Indexed as

Administration, OralAgedAnticoagulantsAspirinCerebrovascular DisordersDouble-Blind MethodDrug Therapy, CombinationFactor Analysis, StatisticalHemorrhageHumansIncidenceMaleMiddle AgedMyocardial IschemiaPlatelet Aggregation InhibitorsPrimary PreventionAnticoagulantsAspirinPlatelet Aggregation InhibitorsWarfarin

Identifiers

PMID9457092

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.