Be Alert for VTE Risk in Giant Cell Arteritis

Aviña-Zubieta JA, Bhole VM, Amiri N, Sayre EC, Choi HK. The risk of deep venous thrombosis and pulmonary embolism in giant cell arteritis: a general population-based study. Ann Rheum Dis (2014)  doi: 10.1136/annrheumdis-2014-205665. [Epub ahead of print Oct 1] 

Giant cell arteritis (GCA) patients face nearly triple the risk of new venous thromboembolism (VTE) over that in the general population, especially in the first year after GCA diagnosis, this Canadian study finds.

The authors compared incidence data for 909 GCA patients diagnosed at the Arthritis Research Centre of Canada in British Columbia between 1996 and 2010 with those from 9,288 matched controls in the general population.

Among all GCA patients, pulmonary embolisms (PE) developed in 18 and 20 experienced deep vein thrombosis (DVT) during the follow-up period.

The increase in incidences (reported as cases/1,000 person-years) were as follows:

VTE: 13.3 for GCA, 3.7 for controls
PE:  7.7 for GCA, 1.9 for controls
DVT:  8.5 for GCA, 2.2 for controls

The highest incident rate ratios for VTE occured within the first year of a GCA diagnosis.

Systemic inflammation, blood vessel dysfunction, and reduced mobility may all promote clotting, the authors say, particularly before GCA is under control. These differences urge increased vigilance among people newly diagnosed with GCA, they add, and preventive measures including anticoagulation therapies.