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Lower income Ontario seniors less likely to access newly approved drugs: Ontario study


An Ontario study of blood thinner prescription patterns for seniors with a common heart rhythm abnormality shows that patients of high socioeconomic status were 1.5 times more likely to be prescribed the new drug dabigatran (marketed as Pradaxa) than patients of low socioeconomic status, before it was covered by the provincial drug plan. However, once dabigatran was covered, this gap disappeared.

Researchers from the Institute for Clinical Evaluative Sciences (ICES) and St Michael’s Hospital conducted the four-year study, which was published in the journal PLOS ONE today. They say these findings demonstrate that there are socioeconomic barriers in accessing new medications when they are not paid for by publicly funded drug plans, and illustrate the need to ensure timely drug approvals in the Ontario Drug Benefit (ODB) Program and other provincial drug plans.

The cost of dabigatran in Ontario is approximately 20 times higher than warfarin. However, it does not require monitoring like warfarin does, and is cost-effective for many patients with nonvalvular atrial fibrillation (a common heart rhythm abnormality). Dabigatran was approved by Health Canada in 2010 but was not added to Ontario’s drug plan until 18 months later, in 2012.

“Based on our findings, we can infer that having a low socioeconomic status was a barrier for seniors in accessing this new drug," says the study’s lead author Dr. Michelle Sholzberg who is a clinical hematologist at St. Michael's Hospital. “Our findings for dabigatran can likely be extrapolated to other new and cost-effective drugs that are slow to be added to provincial drug plans.”

“This is an example of the delays in access that are disproportionately faced by seniors who may be struggling financially, highlighting the importance of timely reimbursement decisions by provinces when new drugs come on the market,” adds Dr. Andreas Laupacis, the study’s senior scientist who is an adjunct scientist at ICES and executive director of the Li Ka Shing Knowledge Institute of St. Michael's Hospital. “The results of this study are also an argument for a publicly funded drug plan that covers Canadians of all ages, because the financial barriers to access we saw with seniors almost certainly also exist for those younger than 65 years of age.”

Reviewing anonymized health records held at ICES for nearly 35,000 seniors in Ontario being treated for nonvalvular atrial fibrillation between 2008 and 2012, the researchers grouped the patients by neighbourhood income levels. They adjusted for demographic variables, comorbid illnesses, medication-related variables and specialist visits.

Among the study’s findings:

  • Individuals of higher socioeconomic status receiving warfarin for nonvalvular atrial fibrillation were more likely to switch to dabigatran in the period between its market approval and inclusion on the provincial formulary. This gradient was eliminated after the drug became available through public reimbursement.
  • Patients living in the highest income quintile neighborhoods were 50 per cent more likely to use dabigatran than those living in the lowest income quintile neighborhoods.

“The influence of socioeconomic status on selection of anticoagulation for atrial fibrillation” was published today in the journal PLOS ONE. The full text may be accessed at http://dx.plos.org/10.1371/journal.pone.0149142.

Author block: Michelle Sholzberg, Tara Gomes, David N. Juurlink, Zhan Yao, Muhammad M. Mamdani, Andreas Laupacis.

The Institute for Clinical Evaluative Sciences (ICES) is an independent, non-profit organization that uses population-based health information to produce knowledge on a broad range of healthcare issues. Our unbiased evidence provides measures of health system performance, a clearer understanding of the shifting healthcare needs of Ontarians, and a stimulus for discussion of practical solutions to optimize scarce resources. ICES knowledge is highly regarded in Canada and abroad, and is widely used by government, hospitals, planners, and practitioners to make decisions about care delivery and to develop policy. For the latest ICES news, follow us on Twitter: @ICESOntario.

St. Michael’s Hospital provides compassionate care to all who enter its doors. The hospital also provides outstanding medical education to future healthcare professionals in 27 academic disciplines. Critical care and trauma, heart disease, neurosurgery, diabetes, cancer care, care of the homeless and global health are among the hospital’s recognized areas of expertise. Through the Keenan Research Centre and the Li Ka Shing International Healthcare Education Centre, which make up the Li Ka Shing Knowledge Institute, research and education at St. Michael's Hospital are recognized and make an impact around the world. Founded in 1892, the hospital is fully affiliated with the University of Toronto.


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