Cost of arthritis: a systematic review of methodologies used for direct costs

A substantial amount of healthcare and costs are attributable to arthritis, which is a very common chronic disease. This paper presents the results of a systematic review of arthritis cost studies published from 2008 to 2013. MEDLINE, Embase, EconLit databases were searched, as well as governmental and nongovernmental organization websites. Seventy-one reports met the inclusion/exclusion criteria, and 24 studies were included in the review. Among these studies, common methods included the use of individual-level data, bottom-up costing approach, use of both an arthritis group and a control group to enable incremental cost computation of the disease, and use of regression methods such as generalized linear models and ordinary least squares regression to control for confounding variables. Estimates of the healthcare cost of arthritis varied considerably across the studies depending on the study methods, the form of arthritis and the population studied. In the USA, for example, the estimated healthcare cost of arthritis ranged from $1862 to $14,021 per person, per year. The reviewed study methods have strengths, weaknesses and potential improvements in relation to estimating the cost of disease, which are outlined in this paper. Caution must be exercised when these methods are applied to cost estimation and monitoring of the economic burden of arthritis.