Evidence map›Paper›PMID 22751234›Full record

ArticleThe British journal of general practice : the journal of the Royal College of General Practitioners2009

What affects anticoagulation control in patients taking warfarin?

Lindsay Smith, Edzard Ernst, Paul Ewings, Jeffrey Allen, Caroline Smith, Catherine Quinlan

Open access · bronzeAbstract read
In one paragraph

Article in The British journal of general practice : the journal of the Royal College of General Practitioners, 2009. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
0.9field-weighted citation impact, top 13% of its field
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

0 citing papers in PubMed, 4 citations in OpenAlex.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

6 authors at 2 institutions in 1 country.

Lindsay SmithEast Somerset Research Consortium, West Coker, Somerset. research@esrec.nhs.uk
Edzard Ernst
Paul Ewings
Jeffrey Allen
Caroline Smith
Catherine Quinlan
Somerset Partnership NHS Foundation Trust · GBNational Health Service · GB

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundThe ageing population is taking an increasing number of both prescribed and non-prescribed medication. Little is known of the potential for adverse drug reactions between these. Warfarin is a commonly prescribed medication, well known for its potential to cause serious adverse reactions in combination with many prescription medicines. It has been suggested that herbal medicines such as garlic, either as a dietary supplement or in cooking, may also interact with warfarin, resulting in poor international normalised ratio (INR) control.

aimTo determine whether, for patients who take garlic as well as warfarin, the proportion of the INR tests in range is lower than in comparable patients who do not take garlic. DESIGN OF THE STUDY: Retrospective study of patients taking prescribed warfarin.

settingPrimary care practices in Somerset and Devon.

methodThree controls (not taking garlic) matched for age, sex, and general practice were compared with each patient self-reporting taking garlic as a supplement. INR results were assessed for the preceding 12 months. Potentially confounding factors were considered, for example diabetes mellitus; all prescribed medication; any bleeding episodes.

resultsNo evidence was found to suggest that garlic consumption either as a supplement or in cooking is associated with more frequent haemorrhagic complications or less control of INR. Poor INR control may, however, be associated with taking larger numbers of prescription medicines, particularly during prescription changes.

conclusionFurther research would be warranted into whether increased INR monitoring is needed when drug changes are made. These data render clinically significant interactions between warfarin and garlic intake unlikely.

Indexed as

AgedAnticoagulantsCase-Control StudiesDrug InteractionsFemaleGarlicHumansInternational Normalized RatioMalePlants, MedicinalRetrospective StudiesWarfarinAnticoagulantsWarfarin

Identifiers

PMID22751234
PMCPMC2714782
OpenAlexW2087660740

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.