reports

Equity in the use and financing of medicines in British Columbia before and after the move to income-based pharmacare

Vancouver, BC, Canada: University of British Columbia (doctoral dissertation).

University of British Columbia, Vancouver, BC, Canada

BACKGROUND: In May 2003, the B.C. government introduced an income‐based pharmacare program, in which subsidy and private payments for prescription drugs are determined according to household income. Given the limited understanding of the equity implications of this policy, the objectives of my thesis were: to determine the degree of income‐related inequity in the use of ACE‐inhibitors, beta‐blockers and statins before and after the introduction of income‐based pharmacare in a population of acute myocardial infarction (AMI) patients; to validate the ability of the Johns Hopkins case‐mix adjusters to predict prescription drug expenditures and use, and; to determine the redistributive effect of the move to incomebased pharmacare on the overall income distribution in B.C. methods: using population‐based administrative databases, i identified all ami patients who survived for at least 120 days after suffering their first ami between 1999 and 2006. according to their household income level, i examined their odds of initiating on ace‐inhibitors, betablockers and statins. among those who initiated i calculated concentration indices for days of therapy on each of these medicines. i validated the use of the acg case‐mix adjusters to predict both expenditures on and use of prescription drugs using generalized linear models and cstatistics. i performed a redistributive analysis to examine whether, and how, income inequality in the province changed as a result of the differences in prescription drug financing after the introduction of income‐based pharmacare.

RESULTS: My results reveal that higher income men and women were significantly more likely to initiate on treatment with beta‐blockers and statins than those in the lowest income quintile. Higher income men were also more likely to initiate on ACE‐inhibitors. Concentration indices reveal that high‐income AMI patients received significantly more days of therapy on all three medicines than low‐income AMI patients. The ACG case mix system was found to have high predictive ability for both prescription drug expenditures and use. I also found that incomebased pharmacare had a redistributive effect that resulted in increased income inequality in B.C.

CONCLUSIONS: My findings suggest that income‐based pharmacare, as it was implemented in B.C., does not meet the health equity standards articulated by Canadians.