Impact of a criteria-based reimbursement policy on the use of respiratory drugs delivered by nebulizer and health care services utilization in Nova Scotia, Canada

Background. In February 2000, the Nova Scotia Seniors' Pharmacare Program announced a change in the reimbursement of respiratory drugs that added specific reimbursement criteria for wet nebulization therapy. Policy implementation coincided with multifaceted interventions to assist patients and providers with the change. Objective. To assess the impact of the new policy and associated interventions on the use of wet nebulization and portable inhaler delivery systems of respiratory drugs and on the utilization of health services. Methods. The administrative claims database identified all beneficiaries (age ≥ 65 yrs) who received at least one respiratory drug prescription in the 12 months before the study. These patients were then grouped into the wet nebulization cohort or the control cohort receiving a metered-dose or a dry-powder inhaler. The study period was from April 1998-February 2002. Use of respiratory drugs, physician visits, and hospitalizations were compared between study cohorts using an interrupted time-series design. Results. A sharp decrease was noted in use of wet nebulization after the policy announcement, along with an increase in use of short-acting β₂-agonists and anticholinergic agents delivered by metered-dose or dry-powder inhaler. From December 1999 to December 2001, in the heavy wet nebulization cohort (a subset of the wet nebulization cohort), wet nebulization use dropped from 100% to 35%; in the wet nebulization cohort, wet nebulization use decreased from 67% to 20%. Rates of spacer device use were 42%, 31%, and 17% in the heavy wet nebulization, wet nebulization, and control cohorts, respectively, in December 2001. Rates of general practitioner visits and hospitalizations for respiratory conditions did not increase in the intervention cohorts after the policy announcement. In fact, relative to the control cohort, health services use in response to the policy and interventions in the wet nebulization cohort decreased. Conclusion. The reimbursement policy resulted in decreased use of respiratory drugs delivered by wet nebulization without a negative impact on general practitioner visits and hospitalizations for respiratory conditions.