Medical costs and adherence in patients receiving aqueous versus pressurized aerosol formulations of intranasal corticosteroids

Intranasal corticosteroid (INS) formulations have different sensory attributes that influence patient preferences, and thereby possibly adherence and health outcomes. This study compares health care use and costs and medication adherence in matched cohorts of patients with allergic rhinitis (AR) using a chlorofluorocarbon-propelled pressurized metered-dose inhaler (pMDI) or aqueous intranasal corticosteroid (A-INS). Florida Medicaid retrospective claims analysis was performed of enrollees aged ≥12 years with at least 1 year of continuous enrollment before their initial AR diagnosis, 1 year for continuous enrollment before their index INS claim, and 18 months of continuous enrollment after their index INS claim during which they received either pMDI or A-INS. pMDI and A-INS patients were matched 1:2 using propensity scores. Nonparametric analyses compared outcomes between matched cohorts at 6, 12, and 18 months of follow-up. A total of 585 patients were matched (pMDI = 195, A-INS = 390). pMDI patients were more adherent to INS, as reflected in their higher median medication possession ratio (53.2% versus 32.7%; p < 0.0001) and fewer median days between fills (73 days versus 111 days; p = 0.0003). Significantly lower median per patient pharmacy fills (34.0 versus 50.5; p < 0.05) and costs ($1282 versus $2178; p < 0.01) were observed among pMDI patients versus A-INS patients 18 months after INS initiation and were maintained when analyses excluded INS fills. Adherence to INS and health care utilization and costs following INS initiation for AR differed by type of formulation received. Our findings suggest patient preferences for INS sensory attributes can drive adherence and affect disease control, and ultimately impact health care costs.