Low-dose aspirin appears to be a safe and effective adjunctive therapy in patients whose giant cell arteritis puts them at increased risk for ischemic vision loss and cerebrovascular accidents, judging from data from a retrospective study.
Dr. Michael S. Lee of the University of Minnesota, Minneapolis, and his colleagues from the Cleveland Clinic Foundation reviewed the charts of 143 patients (76% women; 95% white; mean age 71.8 years) who met the American College of Rheumatology's criteria for giant cell arteritis (GCA). The patients had presented between January 1989 and November 2004 and 73% had a biopsy-proven diagnosis.
All of the patients were treated with corticosteroids after their diagnosis.
But not all the patients remained on steroids for the duration of follow-up, which was several years in some cases, Dr. Lee said in an interview.
Aspirin, clopidogrel, or warfarin was given to 86 patients at some point since their diagnosis.
Of these 86, 18 started this therapy only after experiencing an ischemic event and 68 took one of these agents without a prior ischemic event. The remaining 57 patients never received antiplatelet or anticoagulant therapy.
The mean follow-up was 53.8 months for the antiplatelet-anticoagulant treated group and 46.7 months for the untreated group.
Fewer ischemic events occurred among patients who were on antiplatelet or anticoagulant therapy.
An ischemic event occurred in 11 (16%) of the 68 patients taking antiplatelet or anticoagulant therapy and in 36 (48%) of 75 patients—the 57 patients who were untreated and the 18 patients who had experienced an ischemic event prior to starting therapy, said Dr. Lee.
One or more cerebrovascular risk factors were present in 99 patients (69%).
For those with risk factors, 53 (54%) were on antiplatelet or anticoagulant therapy and 46 (47%) were not.
Of the patients on antiplatelet or anticoagulant drugs, 77% had at least one cerebrovascular risk factor, compared with 61% of the patients not taking these medications.
Nonfatal bleeding occurred in 2 (3%) of 66 patients on aspirin and in 1 (5%) of 20 on warfarin. In contrast, bleeding occurred in 5 (9%) of 57 patients on prednisone (Arthritis Rheum. 2006;54:3306–9).
Antiplatelet or anticoagulant therapy “may reduce the risk of vision loss or hemispheric stroke in patients with GCA. An increased risk of bleeding complications was not observed in this group,” the investigators wrote.
“Low-dose aspirin is relatively well tolerated and safe” and, when there are no contraindications, adjunctive low-dose aspirin should be considered in the treatment of patients with GCA, they added. “We also believe that our results provide a rationale for a prospective, randomized, placebo-controlled trial to further determine the role of adjunctive antiplatelet therapy in GCA.”