Giant cell arteritis in Alaska Natives

Objective: To investigate the incidence of biopsy-proven giant cell arteritis in the Native population of Alaska. Design: Retrospective review of medical diagnostic and Current Procedural Terminology (CPT) codes. Participants: 110 000 Alaska Native patients. Methods: We conducted a retrospective review of medical diagnostic codes for temporal arteritis, giant cell arteritis, and anterior ischemic optic neuropathy in the medical records of 110 000 Alaska Native patients seen between 1983 and 2003. We examined this same database in search of the CPT code for the temporal artery biopsy procedure. We also re-examined all temporal artery biopsy specimens that had been reported as positive. Results: We identified 122 patients whose diagnostic codes matched those of giant cell arteritis, temporal arteritis, or anterior ischemic optic neuropathy. We found that of 20 temporal artery biopsies that had been performed on this group, only 4 were reported to have had positive results. On re-examination of pathologic specimens, 1 of the 4 was found not to meet the latest pathologic criteria for this disease, leaving only 3 cases of biopsy-proven giant cell arteritis. The calculated incidence of giant cell arteritis in the Alaska Native population is approximately 1/100 000 in those over 50 years old. Conclusions: Compared with previous epidemiologic studies performed worldwide, our review suggests a very low incidence of biopsy-proven giant cell arteritis among Alaska Natives.