Evolving patterns in the diagnosis and management of allergy-mediated disorders

Background: This analysis explores the increasing heterogeneity of trends in allergy management under the premise that the practice of allergy has undergone significant changes in national economics, healthcare delivery, and treatment options from 2007 to 2016. Methods: Centers for Medicare and Medicaid Services (CMS) data were obtained for: (1) temporal trends in allergy immunotherapy injection (Current Procedural Terminology [CPT] codes 95115, 95117) and testing (CPT 95004, 95024) from 2007 to 2016; (2) geographic trends; and (3) practitioners administering immunotherapy. Although there are no sublingual immunotherapy (SLIT) CPT codes, billing for unlisted allergy/immunologic services (CPT 95199) were obtained. Results: Since 2007, there were 99.5 million allergy tests and 33.5 million immunotherapy injections billed to Medicare beneficiaries. Increases in testing have outpaced rising immunotherapy administration (49.7% vs 19.6% increase). Significant regional variation in testing rates was noted, with the greatest ratio of testing to immunotherapy in the South (0.35) and smallest ratio in the Northeast (0.18). The maximum unlisted allergy services billed was 594 (of which includes SLIT), compared to annual subcutaneous immunotherapy (SCIT) totals in the millions. The majority of immunotherapy in 2016 was administered by allergists/immunologists (51.6%) followed by otolaryngologists (31.2%), trends that have remained consistent since 2012. Conclusion: Physicians have been more aggressive in the workup of allergy-mediated disorders in recent years. Although differences in allergen load exist, there is tremendous geographic variation in the ratio of testing to immunotherapy. While the role otolaryngologists play in immunotherapy remains stable, allergists manage the majority of patients, reinforcing the importance of interdisciplinary cooperation and outreach. SLIT does not appear to play a significant role in this population.