Abstract

BACKGROUND AND AIMS:

Resistance to activated protein C (APCR) caused by the Leiden mutation to factor V is the most common cause of inherited thrombosis. Patients with inflammatory bowel disease (IBD) are considered to have an increased risk of thromboembolic complications, and the role of APCR as a cause has previously been investigated. In this study, we investigated if APCR was associated with non-thrombotic morbidities in IBD.

PATIENTS/METHODS:

Of 951 patients asked to participate, 389 agreed by returning a signed informed consent and filled questionnaire and took the blood test for APCR. Self-reported IBD-related surgery was used as a rough indicator for increased morbidity.

RESULTS:

APCR was present in 6.6% of patients with Crohn's disease (CD; 10/152) and in 12.7% of ulcerative colitis (UC) patients (30/237). The difference of 6.1% is significant (p=0.039). Among patients with CD and APCR, 9 out of 10 had had surgery, significantly more than among those without APCR (81/142). In patients with UC and APCR, 10 out of 30 had had surgery, still significantly more than in those without APCR (36/207). For the whole group of IBD patients, APCR is associated with a significantly increased risk for thrombosis (p=0.0018), and for the UC group (8/28) p=0.0029, but not for the CD patients alone (2/9), p=0.2323. No other significant differences could be shown for parameters normally related to increased morbidity.

CONCLUSIONS:

APCR in IBD was associated with an increased frequency of IBD-related surgery, which may warrant screening for APCR in therapy-resistant IBD. In patients with APCR, it may be more difficult and/or important to control inflammation.