Do policy changes in the pharmaceutical reimbursement schedule affect drug expenditures? Interrupted time series analysis of cost, volume and cost per volume trends in Sweden 1986-2002.

The last decades increasing pharmaceutical expenditures in Sweden and other western countries have created a need for reforms to reduce the trend. The aim was to analyse if reforms concerning the pharmaceutical reimbursement scheme in Sweden during the years 1986-2002 were associated with changes in cost, volume and cost per volume of pharmaceuticals. Effects of changes in the reimbursement schedule during the study period were evaluated for all registered pharmaceuticals in Sweden and for five indicator drug groups. Five policy changes during the study period were assessed. Three concerned increased patient co-payment (January 1, 1991; January 1, 1995 and June 1, 1999), one the introduction of reference based pricing and increased co-payment (January 1, 1993) and one a new structure of the reimbursement schedule (January 1, 1997). The National Corporation of Swedish Pharmacies provided pharmaceutical delivery data for all Swedish pharmacies. Possible breaks in the trend associated with the investigated reforms were analysed with linear segmented regression analysis. This showed that increased co-payments were not associated with changed level or slope of cost and volume. The new reimbursement schedule was associated with a decreased level of cost and volume, both for all drugs combined and for several of the indicator drug groups. It was also associated with an increased slope for both volume and cost in some indicator drug groups and for all drugs. Introduction of reference based pricing was associated with a reduced slope of cost/defined daily doses (DDD) in all of the indicator drug groups and for all drugs. The analysis showed that major changes in the reimbursement system such as the introduction of a new reimbursement schedule and reference based pricing were associated with reductions in cost and volume for the new reimbursement schedule and cost per volume for reference based pricing.