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
The authors compared the number of new cases of VTE arising
in just under 50,000 children and adults with inflammatory bowel disease and
more than 477,000 members of the general public.
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.