Self-Reported Productivity Losses of People with Rheumatoid Arthritis in Alberta, Canada

ABSTRACT

To estimate the annual cost of productivity losses per person with RA by 0.5 increment in HAQscore, and the annual cost of productivity losses for Alberta province.

Using data from the Alberta Biologics Registry - a prospective observational cohort of consecutive patients receiving DMARD or anti-TNF therapies created in 2004, we compared the mean and median costs of productivity losses per patient per year between HAQ-score categories using multiple linear and quantile regressions, respectively. We used a prevalence-based approach to estimate the cost (in 2010 CA$) of productivity losses of RA for Alberta.

In total there were 1222 patients with RA interviewed at the baseline. Of this, 358 were the “current employees” and 204 were the “previous employees” totalling 563 patients for analyses. For all HAQ-score categories, the mean (median) of the cost per patient per year was estimated at $18,242 ($3,840). The cost was increasing along with the HAQscore increase. The lowest cost ($6,295) was found in category HAQ<=0.5 and the highest ($31,095) in category HAQ>2.0. The significant differences were found between the worse categories (HAQ>1.5) and the better categories (HAQ<=1.5). The mean costs of productivity losses of RA for the province of Alberta were estimated at $270 million. Conservatively, if median was used for mean, the costs for province would be $57 million.

The results suggest that an improvement in the controlling of RA could have a significant economic impact in Alberta and that preventing HAQ-score from the worse categories may be associated with substantial savings in terms of productivity losses.

Keywords: