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Usefulness of factor V Leiden mutation testing in clinical practice
Ellen Ø Blinkenberg1, Ann-Helen Kristoffersen, Sverre Sandberg
1Center for Medical Genetics and Molecular Medicine, Haukeland University Hospital, Bergen, Norway. ellen.okland.blinkenberg@helse-bergen.no
European Journal of Human Genetics : EJHG
|March 25, 2010
Summary
The activated protein C resistance (APCR) and factor V Leiden mutation (FVL) test has low clinical usefulness. Many tests are ordered without clear indications, potentially leading to patient harm due to unwarranted advice.
Area of Science:
- Medical Diagnostics
- Clinical Genetics
- Hematology
Background:
- The activated protein C resistance (APCR) and factor V Leiden mutation (FVL) test are used to assess thrombophilia risk.
- Understanding the clinical utility and physician practices surrounding APCR/FVL testing is crucial for optimizing diagnostic strategies.
Purpose of the Study:
- To investigate the clinical usefulness of APCR/FVL testing in Norway.
- To examine the indications for testing, patient follow-up, and variations in testing practices among physicians.
Main Methods:
- A questionnaire survey was distributed to Norwegian physicians ordering APCR/FVL tests.
- Response rate was 70% (267/383).
- Data analyzed included test indications, patient history, and physician-reported follow-up actions.
Main Results:
- 46% of tests were predictive (risk assessment in healthy individuals), with 42% patient-initiated and 24% for oral contraceptive screening.
- 54% of tests were diagnostic (for patients with VTE, stroke, or myocardial infarction history).
- Prevalence of FVL heterozygotes was similar in predictive (26%) and diagnostic (20%) groups. Only predictive tests influenced patient follow-up, and normal results sometimes led to unwarranted advice against antithrombotic measures.
Conclusions:
- The clinical usefulness of APCR/FVL testing is generally low, with many tests ordered for unsubstantiated indications.
- Physician advice and patient management can be negatively impacted by test results, particularly normal findings, potentially causing patient harm.
- Recommendations for more judicious use of APCR/FVL testing are warranted.
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