Incidence of herpes zoster in patients with giant cell arteritis: a population-based cohort study

Methods. Utilizing the resources of the Rochester Epidemiology Project, all incident cases of GCA diagnosed between 1 January 1950 and 31 December 2004 were identified. For each GCA patient, two subjects without GCA of the same gender and similar age and length of medical history were randomly selected from the population. Patients were followed until death, last contact or 31 December 2006. Results. The study population included 204 GCA patients and 407 non-GCA subjects. The GCA cohort had 163 (79%) women and 41 (21%) men, with a mean age of 76.0 (8.2) years. The non-GCA cohort had 325 (80%) women and 82 (20%) men, with a mean age of 75.6 (8.4) years. During follow-up, 21 GCA patients and 38 non-GCA subjects developed HZ. There was no difference in the development of HZ in GCA patients compared with non-GCA patients [hazard ratio (HR): 1.22; 95% CI 0.71, 2.08; adjusted for age, sex and calendar year]. No GCA patient and one non-GCA subject developed HZ within 6 months of index date. The frequency of post-herpetic neuralgia was similar between both groups (P = 0.64). Conclusions. Patients with GCA do not appear to be at increased risk of HZ compared with the general population, even during the first 6 months of therapy when glucocorticoid doses are usually highest.