Health care resource use and associated costs among patients with seasonal versus perennial allergic rhinitis.

Background: Health care resource use (HRU) and costs among patients with seasonal allergic rhinitis (SAR) and perennial allergic rhinitis (PAR) have not been widely studied.
Objective: To develop an algorithm to classify patients with SAR and patients with PAR, and to evaluate treatment patterns, HRU, and costs among these patients.
Methods: Patients with allergic rhinitis (AR) were identified retrospectively by using electronic medical records and administrative claims data, with an index date as the earlier of the date of AR diagnosis or allergy medication use. Patients with AR were followed-up from 12 months before the index date through 12 months after the index date (follow-up) and were classified as SAR or PAR based on medication patterns during follow-up. AR-related HRU, allergy immunotherapy administration, and costs per patient per year during follow-up were compared between patients with SAR and those with PAR, with analyses stratified by asthma diagnosis before the index date and by physician specialty (primary care physician versus specialist).
Results: Approximately 23% of patients with AR were classified as having PAR and 77% as having SAR. During follow-up, the patients with PAR had more allergy medication prescriptions versus the patients with SAR (8.0 versus 2.4 prescriptions), higher prescription medication costs ($1551 versus $313), higher allergy immunotherapy cost ($180 versus. $118), and higher total AR-related costs ($1944 versus $643); all with p < 0.001. Patients with asthma had higher costs than those without asthma. Patients seen by a specialist has higher costs than those treated by a primary care physician.
Conclusion: Patients with PAR experienced more AR-related prescription drug use and higher health care costs than patients with SAR, with prescription drug costs being the main cost driver. Treatments that reduce the need for ongoing prescription medication use have the potential to be cost saving.