POS0554 MEDICAL COST AND RESOURCE USE IN PATIENTS STARTING TREATMENT FOR RHEUMATOID ARTHRITIS TREATED WITH AND WITHOUT CORTICOSTEROIDS IN JAPAN

Abstract

Background:The 2019 update of the European League Against Rheumatism (EULAR) treatment recommendations strongly recommends co-administration of corticosteroids (CSs) with conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) in patients with RA as bridging therapy to improve the success rate of the first-line treatment and to avoid disease flare-ups1; however, current treatment guidelines for RA in Japan do not clearly mention about their use. Poor disease management after the initial diagnosis can affect the overall use of health services and the economic burden on patients.Objectives:To describe medical costs and resource use in patients with early RA treated with and without oral or injectable corticosteroids (CSs) as part of their initial treatment with disease-modifying antirheumatic drugs (DMARDs) in Japan.Methods:We used a large Japanese administrative claims database constructed by the Japan Medical Data Center (JMDC)2. Patients with the International Classification of Diseases 10th revision (ICD-10) codes for RA were enrolled at the first DMARDs prescription after no DMARDs prescription period for 6-months (index date) in the period from 1/1/2012 to 12/31/2017. Patients who were observable for 12 months after the index date as a follow-up period were included. Patients treated with CSs within the follow-up period were compared with those without them (CS and non-CS group). The primary endpoint was mean medical cost per patient in the 12-month follow-up period. The secondary endpoints were costs for drugs, treatments, and materials and the proportions of patients using the subcategories of each resource. Drugs were divided into medications for RA or for comorbidities including adverse events (AEs). Costs in JPY were converted into EUR (1 EUR = 125 JPY in 2020).Results:Eligible patients of 1,670 and 1,487 were identified as the CS and non-CS group (median age: 51 years and 50 years). Total mean costs were significantly higher in the CS group (CS, 4,448 EUR, non-CS 3,208 EUR; P< 0.05). Drug, treatment, and material costs were significantly higher in the CS group than in the non-CS group (drug for RA and AEs, CS 2,367 EUR, non-CS 1,581 EUR, P < 0.05; drug for RA only, CS 2,265 EUR, non-CS 1,516 EUR, P < 0.05; treatment, CS 1,987 EUR, non-CS 1,562 EUR, P < 0.05; material, CS 94 EUR, non-CS 65 EUR; P < 0.05). The resource use in almost all drug subcategories were higher in the CS group (Table 1), as well as in all treatment and material subcategories.Table 1.Number and proportion of patients who used drugsType of drugDrug use, n (%)CS (N = 1,670)Non-CS (N = 1,487)P-valuecsDMARDsTotal1,635 (97.9)1,447 (97.3)0.328 Methotrexate1,481 (88.7)1,315 (88.4)0.870 Others790 (47.3)551 (37.1)< 0.001bDMARDsTotal342 (20.5)181 (12.2)< 0.001 TNFi252 (15.1)129 (8.7)< 0.001 IL6i93 (5.6)40 (2.7)< 0.001 T-cell40 (2.4)17 (1.1)0.012AnalgesicsTotal1,512 (90.5)1,274 (85.7)< 0.001 Acetaminophen379 (22.7)273 (18.4)0.003 Acetaminophen / Opioids84 (5.0)37 (2.5)< 0.001 NSAIDs1,459 (87.4)1,214 (81.6)< 0.001 Opioids16 (1.0)10 (0.7)0.491 Others198 (11.9)101 (6.8)< 0.001AntibioticsTotal1,086 (65.0)873 (58.7)< 0.001 Antibacterial drugs1,022 (61.2)800 (53.8)< 0.001 Antifungal drugs133 (8.0)86 (5.8)0.019 Antiviral drugs172 (10.3)129 (8.7)0.136 Antiparasitic drugs5 (0.3)8 (0.5)0.443Anti-osteoporotic drugs341 (20.4)95 (6.4)< 0.001bDMARDs=biological disease-modifying antirheumatic drugs; CSs=corticosteroids; csDMARDs=conventional synthetic disease-modifying antirheumatic drugs; IL6i=interleukin-6 inhibitor; NSAID=non-steroidal anti-inflammatory drug; T-cell=selective T-cell co-stimulation modulator; TNFi=tumor necrosis factor α inhibitor; P-values were calculated using Chi-square testConclusion:Patients with early RA treated with CSs in the first year after starting DMARDs tended to use more resources and have higher medical costs than patients not treated with CSs.