Inflammatory bowel disease more than doubles the risk of a
potentially fatal blood clot in the legs or lungs (VTE), reveals research
published online in the journal Gut.
Inflammatory bowel disease is an umbrella term used to include Crohn's disease and ulcerative colitis.
Venous thromboembolism (VTE), which includes deep vein thrombosis (DVT), pulmonary embolism (PE), and superior sagittal sinus thrombosis (SSST), affects around 2 in every 1000 people in developed countries annually.
The study period spanned 1980 to 2007 and took account of known VTE risk factors, such as a broken bone, cancer, surgery and pregnancy.
The results showed that the risk of VTE was twice as high in those with inflammatory bowel disease as it was in the general public.
VTE is more common in older people, irrespective of whether they have inflammatory bowel disease or not, but the risk of VTE in patients with inflammatory bowel disease was highest in younger age groups, when compared with the general public.
In those aged 20 or younger, the likelihood of a pulmonary embolism, which can be fatal, was low, but it was six times as common among those with inflammatory bowel disease as it was among the general public in this age group.
Even after taking account of concurrent cardiovascular disease, diabetes, congestive heart failure, the use of hormone replacement therapy or antipsychotic drugs, all of which are known to heighten the likelihood of VTE, the risk still remained up to 80% higher.
The findings suggest that inflammatory bowel disease may be an independent risk factor for clot formation, say the authors.