Abstract
Background:
Subcutaneous(SCIT) and sublingual (SLIT) allergen immunotherapy is a safe and effective treatment of allergic rhinitis, but high levels of compliance and persistence are crucial to achieving the desired clinical effects. The objective was therefore to assess levels and predictors of compliance and persistence among grass & tree pollen, and house dust mite immunotherapy users in real-life, and estimate costs of premature discontinuation.
Methods:
A retrospective analysis of a community-pharmacy database from The Netherlands containing data from 6486 patients starting immunotherapy for one or more of the allergens of interest between 1994 and 2009. 2796 patients received SCIT and 3690 received SLIT. Time-to-treatment discontinuation was analyzed and included Cox proportional Hazard models with time-dependent covariates, where appropriate.
Results:
82% per cent of users did not reach the minimally required duration of treatment of three years (SCIT: 77%, SLIT: 93%). Median durations for SCIT and SLIT users were 1.7 and 0.6 years, respectively. Of the persistent patients, 58 per cent were never late in picking up their medication from the pharmacy. Other independent predictors of premature discontinuation were prescriber, with general practitioner patients demonstrating longer persistence than those of allergologists and other medical specialists, multiple-allergen therapy, higher socioeconomic status, and younger age. Direct medication costs per nonpersistent patient were €3,800.
Conclusion:
Persistence is better in SCIT users than in SLIT users. Further studies are needed to determine whether persistence can be improved by administering the therapy close to the patient's home.
- © 2012 ERS
