We have carried out the CAN-AIM ‘demonstration project’ on ‘Comparative Effectiveness of anti-Tumor Necrosis Factor agents versus traditional Disease-Modifying agents in reducing orthopedic surgery in rheumatoid arthritis.

A manuscript, that summarizes these results, was published to the peer-reviewed journal Arthritis Care and Research in August 2015. The article is one of the journal’s most highly accessed articles. We analyzed a cohort of new-onset RA patients, identified from Quebec’s physician billing and hospitalization databases from 2002-2008; who were beneficiaries of the provincial drug plan.

We also presented results at the EUropean League Against Rheumatism (EULAR) meeting in 2014 in Paris, France and at EULAR 2015 in Rome, Italy.

Their data were linked to the pharmacy dispensation database. We used a series of multivariable Cox regression models with time-dependent variables representing alternative measures of cumulative effects of past use of: 1) methotrexate (MTX), and 2) other disease-modifying anti-rheumatic drugs (DMARDs), quantified over different time windows. In parallel with the Quebec analyses, we have been working on similar datasets from Manitoba, Nova Scotia, Ontario, and British Columbia.

This involved considerable efforts necessary to clean the data, as well as to homogenize variables definitions and analytical methods across the 5 provinces. We have finalized the data cleaning and coding programs for each province.

We have published a second manuscript in the Journal of Rheumatology which also looks at Ontario. Results suggest that longer exposure to methotrexate or other DMARDs within the first year after RA diagnosis is associated with longer time to joint replacement surgery

Overall, the demonstration project confirmed the CAN-AIM team’s abilities and skills in both (i) using advanced methodology to address a challenging issue regarding drugs’ effectiveness and (ii) efficient and productive networking/collaboration of investigators, research trainees and staff from 5 provinces.