impact factor



Seasonal incidence of biopsy-proven giant cell arteritis: a 20-year retrospective study of the University of California Davis Medical System

1, 2, 3


  1. Department of Ophthalmology, Roski Eye Institute, University of Southern California, Los Angeles, and Department of Ophthalmology and Vision Science, University of California Davis, Sacramento, CA, USA.
  2. Department of Statistics and Bio Statistics, California State University East Bay, Hayward, CA, USA.
  3. Department of Ophthalmology, Roski Eye Institute, University of Southern California, Los Angeles, CA, and Department of Ophthalmology, Moran Eye Center, University of Utah, Salt Lake City, UT, USA.

2019 Vol.37, N°2 ,Suppl.117
PI 0090, PF 0097

Free to view
(click on article PDF icon to read the article)

PMID: 30620274 [PubMed]

Received: 21/01/2018
Accepted : 30/07/2018
In Press: 07/01/2019
Published: 21/05/2019


Giant cell arteritis (GCA) is a vasculitis that affects large and medium sized arteries. The aetiology of GCA is unknown and numerous risk factors have been proposed. In this article, we evaluate the incidence of biopsy-positive GCA in Northern California and assess for seasonal variation.
We performed a retrospective review based on billing codes of temporal artery biopsies performed at the University of California, Davis from 2003 to 2014.
We identified 174 biopsies (119 female, 55 male). Of these, 21 positive biopsies were female while 8 were male. Although three times as many women had a positive biopsy compared to men, twice as many biopsies were performed on women. Women were not found to have a significantly higher risk of developing GCA over men. Patients with a positive biopsy averaged 76.4±8.9 years of age. The odds of having a positive biopsy increased significantly with age. Positive biopsies were significantly more likely to occur in the months of May through July than the rest of the year (p<0.028).
Our retrospective study is the first report of the seasonal incidence of biopsy-proven GCA in California. Our data suggest that increased age and summer months are risk factors for developing biopsy-proven GCA in our region.

Rheumatology Article