Cost effectiveness of the determination of autoantibodies against cyclic citrullinated peptide in the early diagnosis of rheumatoid arthritis
- Karsten Conrad ( )
- Published Online First 11 January 2008
Aims: This study aims to estimate the incremental cost-effectiveness ratio (ICER) of antibodies against cyclic citrullinated peptides (aCCP) in the early diagnosis of rheumatoid arthritis (RA).
Methods: A Markov model was utilised to model 10 year progression of RA in patients first diagnosed as undifferentiated arthritis (UA) and to estimate the incremental costs and quality adjusted life years (QALYs) of using aCCP additionally to ACR criteria. Impact of later diagnosis and therapy due to non-use of aCCP was modelled as increased HAQ-progression. Utilities were assigned to HAQ-states for calculating QALYs. Uncertainty was analysed using univariate and probabilistic sensitivity analyses (Monte-Carlo-Simulation).
Results: Baseline ICER was 930 Euro/QALY. Univariate sensitivity analyses identified the impact of later diagnosis on HAQ progression as major source of uncertainty resulting in an ICER range from “dominance” to 153,092 Euro/QALY, compared to a maximum ICER of 4,870 Euro/QALY for other variables. Monte Carlo simulation resulted in a 95%-uncertainty interval from –3,537 Euro/QALY (dominance) to 5,429 Euro/QALY; when indirect costs were considered, Monte Carlo simulation resulted in a 95%-uncertainty interval from –78,115 Euro/QALY (dominance) to –23,444 Euro/QALY (dominance).
Conclusions: Using aCCP in the diagnosis of RA in patients with UA is likely to be a cost-effective strategy compared to ACR-criteria alone. Considering indirect costs, aCCP seems to be a cost saver. There is a clear need for more research relating the effects of an early or early diagnosis and therapy on the long-term course and resulting functional impairment of RA as measured by the HAQ.