BMJ  2007;334:1127 (2 June), doi:10.1136/bmj.39226.442083.3A

Letters

Thromboprophylaxis for adults in hospital

Prophylaxis for medical inpatients is not entirely proven

I have three concerns with regard to the editorial by Fitzmaurice and Murray.¹ Firstly, a recent meta-analysis on anticoagulant prophylaxis to prevent symptomatic venous thromboembolism (VTE) in 19 958 hospitalised medical patients showed only modest benefit.² The numbers needed to treat were 345 (absolute risk reduction 0.29%) to prevent one pulmonary embolism (PE) and 400 (0.25%) to prevent a fatal PE. The difference in symptomatic DVT prevention did not reach significance, and neither did an increase in major bleeding (0.14% absolute increase). Before rushing to use prophylactic anticoagulants in medical patients, clinicians should remember this and target only high risk medical patients (as highlighted in the table¹).

Secondly, Fitzmaurice and Murray report that VTE causes 25 000 potentially preventable deaths. However, this is merely an estimate that is based on extrapolation from European data.³ The authors of the Department of Health's report indicate that the data on VTE in hospital patients are not sufficiently robust to enable secure conclusions to be drawn and the department is urged to initiate research to establish an accurate measure of death from VTE.³ Furthermore, the meta-analysis indicated that anticoagulant prophylaxis had no effect on all cause mortality.³

Thirdly, to date, no studies have assessed the cost effectiveness of anticoagulant prophylaxis to prevent symptomatic VTE in hospitalised patients.² The authors of the meta-analysis comment that because anticoagulant prophylaxis in medical inpatients has potential harm, increases healthcare costs, and is associated with modest treatment benefit in terms of absolute risk reduction, its use should be selective and limited to higher risk medical patients. Perhaps this is why NICE has produced a report only in surgical patients.⁴

Royal Wolverhampton Hospitals, Wolverhampton WV10 0QP

---

Competing interests: None declared.

References

1. Fitzmaurice DA, Murray E. Thromboprophylaxis for adults in hospital. BMJ 2007;334:1017-8. (19 May.)[Free Full Text]
2. Dentali F, Douketis JD, Gianni M, Lim M, Crowther MA. Meta-analysis: anticoagulant prophylaxis to prevent symptomatic venous thromboembolism in hospitalised medical patients. Ann Int Med 2007;146: 278-88.
3. House of Commons Health Committee. The prevention of venous thromboembolism in hospitalised patients. Second report of session 2004-5. London: Department of Health, 2007.
4. National Institute for Health and Clinical Excellence. Venous thromboembolism: reducing the risk of venous thromboembolism in patients undergoing surgery. London: NICE, 2007. http://guidance.nice.org.uk/CG46

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

Relevant Article

Thromboprophylaxis for adults in hospital

David A Fitzmaurice and Ellen Murray
BMJ 2007 334: 1017-1018. [Extract] [Full Text] [PDF]

Rapid Responses:

Read all Rapid Responses

Thromboprophylaxis needs to start in the emergency department

Rhian S Farquharson, et al.
bmj.com, 6 Jul 2007 [Full text]