Immune-mediated diseases may increase VTE risk
MedWire News: People admitted to hospital with immune-mediated diseases such as rheumatoid arthritis and systemic lupus erythematosus (SLE) may have an increased risk for subsequent venous thromboembolism (VTE), data from the UK show.
"Although VTE has traditionally been considered a surgical condition, the vast majority of hospitalized patients with symptomatic VTE have not undergone recent surgery," note Michael Goldacre (University of Oxford) and colleagues.
Recent evidence suggests that immune-mediated diseases may play a role in VTE risk, they add.
To investigate this potential association, Goldacre and team analyzed the medical records of patients admitted to hospital with a range of immune-mediated diseases. They compared the rate of VTE (deep vein thrombosis and pulmonary embolism) among these patients with the rate in a reference group of people who were hospitalized with minor, non-immune-related conditions.
The researchers obtained their data from the Oxford Record Linkage Study (ORLS) at two different points in time: 1968-1998 (n=313,717, 47% women) and 1999-2008 (n=187,609, 46% women), as well as the English national Hospital Episode Statistics (HES) database (1999-2008, n=3,707,315, 41% women).
They found that patients with autoimmune conditions had significantly greater risks for VTE in all three cohorts relative to those with no immune disease.
Of note, rate ratios for patients with, versus those without immune disease varied according to the specific disease and were highest among those with SLE, at 3.61, 4.60, and 3.71 in the ORLS 1968-1998, ORLS 1999-2008, and English HES datasets, respectively.
Consistently high levels of risk (rate ratio>2.0) were also found for polyarteritis nodosa, chronic active hepatitis, dermatomyositis and polymyositis, diabetes mellitus, multiple sclerosis, and Sjogren's syndrome.
Goldacre and co-authors comment that the increased risks for VTE may have different underlying causes in each disease or may be the result of a true inflammatory effect on coagulation.
They conclude in the journal BMC Medicine that their findings need independent confirmation or refutation, "but, if confirmed, there may be a role for thromboprophylaxis in some patients with these diseases," they say.
MedWire (www.medwire-news.md) is an independent clinical news service provided by Current Medicine Group, a trading division of Springer Healthcare Limited. © Springer Healthcare Ltd; 2011
By Laura Dean