THU0632 Retrospective Analysis of The Association between anti-cyclic Citrullinated Peptide Positivity and Healthcare Costs among Patients with Rheumatoid Arthritis Initiating Conventional Disease-Modifying Antirheumatic Drugs
Authors: S. Johnston, C. Patel, K. Wilson, D. Spencer, L. Rosenblatt
Journal: Annals of the Rheumatic Diseases (2016)

<h3>Background</h3> A recent retrospective analysis of US insurance claims data suggested that, among patients newly diagnosed with RA, those who were anti-cyclic citrullinated peptide (anti-CCP) and/or rheumatoid factor (RF) positive (+) had increased RA-related healthcare costs over a 6-month post-diagnosis period compared with those who were anti-CCP/RF negative (–).<sup>1</sup> Identification and treatment of this poor prognostic factor in the realm of RA diagnosis per the ACR guidelines appear to be of value. <h3>Objectives</h3> To investigate the potential role of anti-CCP status in association with clinical outcomes and healthcare costs in conventional (c)DMARD-naïve patients with RA using real-world data. <h3>Methods</h3> This was a retrospective, observational cohort study using the MarketScan® US administrative commercial claims and laboratory results databases. Patients included in this study had initiated cDMARD therapy between 1 January 2006 and 1 July 2014 (initiation=index), were aged ≥18 years at index, were continuously enrolled for 12 months before (baseline) and 12 months after (follow-up) index, did not receive cDMARDs or biologics during baseline, had an anti-CCP test result and had ≥2 medical claims with diagnoses of RA during baseline to 3 months after index. Patients were designated anti-CCP+ if their anti-CCP laboratory value was ≥20 IgG Ab units/mL. The study outcomes were all-cause and RA-related (i.e. medical claims with a diagnosis of RA or claims for cDMARDs and biologics) healthcare costs measured over the 12-month follow-up period. Generalized estimating equations were used to estimate the difference in healthcare costs from baseline to follow-up between anti-CCP+ and anti-CCP– patients (i.e. difference-in-difference [DiD]). <h3>Results</h3> The study included 635 patients: 391 anti-CCP+ (mean age 52 years; 81% female); 244 anti-CCP– (mean age 52 years, 80% female). Anti-CCP+ and anti-CCP– patients differed substantially with respect to baseline all-cause healthcare costs (mean [SD] anti-CCP+: $7650 [$12,901], anti-CCP–: $12,591 [$23,922]; p&lt;0.001), but not RA-specific costs (mean [SD] anti-CCP+: $809 [$2683], anti-CCP–: $891 [$2629]; p=0.239). In the DiD analysis, which adjusts for baseline differences between groups, anti-CCP+ patients experienced increases in all-cause total healthcare costs that were $2756 greater (p&lt;0.001) than those of anti-CCP– patients; this result was primarily driven by greater increases in outpatient costs ($2274; p&lt;0.001; Table). Analyses of RA-related healthcare costs were directionally consistent across the categories. <h3>Conclusions</h3> After accounting for baseline differences between anti-CCP+ and anti-CCP– patients, anti-CCP+ patients9 healthcare costs increased substantially more than anti-CCP– patients over a 12-month follow-up period. Among patients with RA who are newly initiating cDMARDs, anti-CCP positivity may serve as an identifiable predictor for markedly increased future healthcare costs, therefore establishing a need for a more appropriate treatment for cost reduction. <h3>References</h3> Johnston S, et al. J Manag Care Pharm 2015;21(Suppl. 10a):S69. <h3>Disclosure of Interest</h3> S. Johnston Employee of: Truven Health Analytics; Truven Health Analytics was paid by Bristol-Myers Squibb to conduct this study, C. Patel Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, K. Wilson Employee of: Truven Health Analytics, which was contracted by BMS to conduct this study, D. Spencer Grant/research support from: Bristol-Myers Squibb, L. Rosenblatt Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb