Incidence and Prevalence of Granuloma Annulare in the United States.

Importance: Although several single-center studies have estimated that granuloma annulare may account for approximately 0.1% to 0.4% of new patients presenting to dermatologists, large-scale population-based studies estimating the prevalence and incidence of granuloma annulare are lacking.
Objectives: To estimate the population-based incidence and prevalence of granuloma annulare in the United States and to identify the most commonly prescribed treatments.
Design, Setting, and Participants: This cross-sectional study used deidentified data from the Optum Clinformatics Data Mart Database from January 1, 2017, to December 31, 2018, to identify patients with granuloma annulare.
Main Outcomes and Measures: After validating an approach to classify patients with granuloma annulare using International Statistical Classification of Diseases and Related Health Problems, Tenth Revision codes, the primary outcomes were age-, sex-, and race/ethnicity-specific annualized incidence and prevalence estimates for granuloma annulare. In addition, treatment use within 6 to 12 months after the first diagnosis of granuloma annulare was examined. Confidence intervals for prevalence and incidence estimates were computed assuming a binomial distribution using the Wilson score method. Age-, sex-, and race/ethnicity-specific incidence and prevalence estimates were compared using the χ2 test.
Results: A total of 11 608 patients with incident granuloma annulare (8680 female patients [74.8%]; mean [SD] age, 56.5 [18.8] years) and 17 862 patients with prevalent granuloma annulare (13 548 female patients [75.8%]; mean [SD] age, 56.6 [18.5] years) were identified during the study period. The overall annualized incidence of granuloma annulare was 0.04%, or 37.9 (95% CI, 36.9-38.9) per 100 000, and the overall annualized prevalence of granuloma annulare was 0.06%, or 58.3 (95% CI, 57.1-59.5) per 100 000. The incidence and prevalence of granuloma annulare were highest in the fifth decade of life. The incidence and prevalence of granuloma annulare were higher among women (incidence: female to male ratio, 2.8:1; prevalence: female to male ratio, 3.0:1). Within 6 months of their first diagnosis, 4822 patients (41.5%) filled a prescription for a topical corticosteroid, and 1087 patients (9.4%) received an intralesional injection. Within 6 months of their first diagnosis, oral tetracycline prescriptions were filled by 820 patients (7.1%), and hydroxychloroquine prescriptions were filled by 268 patients (2.3%).
Conclusions and Relevance: Granuloma annulare is a rare disease in the United States that is more common among women and middle-aged to older individuals. The findings of this cross-sectional study provide important background regarding the basic epidemiology and overall burden of granuloma annulare in the United States. Future studies are needed to better understand the association of granuloma annulare with quality of life and the most optimal treatment approaches for this condition.