The economic burden of rheumatoid arthritis: beyond health care costs.

Rheumatoid arthritis (RA) not only causes significant morbidity, but also leads to substantial losses in terms of productivity that have a negative impact on the individual and the society. In countries, such as Canada, the US, and the UK, it is known that the costs to the economy in terms of sick leave and work-related disability run into billions of dollars. However, putting an accurate figure on these losses is not entirely straightforward. Most health-related studies use the "human capital" approach, which treats human beings as assets. A figure for lost productivity is calculated by multiplying hours lost by the hourly wage rate. It is a method that is not without its critics because of its emphasis on earning power, which discriminates against non-earners. Another method is the "friction-cost" approach, whereby absenteeism is only recorded if the missed work requires extra hours undertaken, either by the employee himself, or by the others. A third method is the "willingness-to-pay" approach which values life according to an individual's preference to avoid illness with an imputed monetary valuation on the various health outcomes being considered. A number of studies have shown that biologic RA treatments provide productivity benefits in terms of maintaining employment, as well as reducing absenteeism and presenteeism. Going forward, an approach recently adopted by the present authors with encouraging preliminary results, the Valuation of Lost Productivity, takes into account a wide range of factors to provide a measure of productivity that is as accurate as possible.