Thrombophilia Not a Major Player in VTE in Patients With IBD

By Reuters Staff

August 06, 2021

NEW YORK (Reuters Health) - Thrombophilia does not appear to add to the risk of venous thromboembolism (VTE) in patients with inflammatory bowel disease (IBD) over the risk attributed to the IBD-related inflammation, according to a small case-control study.

In contrast to inflammation and known provoking factors such as immobilization and surgery, thrombophilia does not appear to be a risk factor for VTE among patients with IBD, researchers report in the Journal of Clinical Gastroenterology.

Patients with IBD have a high risk of VTE but the underlying mechanism remains unclear, Dr. Henit Yanai of the IBD Center at Rabin Medical Center in Petah-Tikva, Israel, and colleagues write.

It's been suggested that ongoing inflammation is the chief risk factor for thrombosis in patients with IBD. However, most flaring IBD patients with active inflammation do not suffer a VTE event, they point out.

They assessed the role of thrombophilia in VTE risk in 44 case patients with IBD-VTE and 127 matched controls with VTE but not IBD (non-IBD-VTE).

In both groups, most VTE events had a clear etiology and were considered provoked events.

In IBD-VTE patients, immobilization/hospitalization was the most common provoking event. Most patients with IBD-VTE had active IBD at the time of the VTE event.

Provoked and unprovoked VTE rates were similar between cases and controls. Rates of thrombophilia were also similar among IBD-VTE case patients and non-IBD-VTE control patients (40.9% and 53.5%, respectively, P=0.14).

However, among those with unprovoked VTE, thrombophilia rates were significantly lower in the IBD-VTE group compared with non-IBD-VTE control group (42.1% vs.70.7%, respectively, P=0.03).

Among case patients with IBD-VTE, an unprovoked event and negative thrombophilia, 77% had active inflammation at the time of VTE.

The findings, say the researchers, suggest that either "inflammation or other novel pathways" drive VTE in patients with IBD.

"We have shown that patients with IBD are no more likely to have underlying thrombophilia when compared with the general population regardless of disease activity," they note.

"Our research supports the clinical practice of not performing an exhaustive thrombophilia workup with its associated cost for patients with IBD. We suggest patients with IBD should be worked up in a similar manner to patients without IBD and believe our data lends credence to such an approach," they say.

Patients diagnosed with IBD should be evaluated for a personal and family history of thrombosis and use of prothrombotic drugs, according to the authors.

It has also been suggested that IBD patients be screened for risk factors associated with the development of VTE, such as air travel, obesity, advanced age, smoking, as well as specific IBD-related factors, such as hospitalization, immobilization, surgery, previous and current medications, they note. Screening for genetic and acquired risk factors for VTE is recommended in a subset of patients diagnosed with VTE, mostly in cases of unprovoked VTE events.

SOURCE: Journal of Clinical Gastroenterology, online July 7, 2021.