FRI0372 DMARD TREATMENT AND OPIOID USE IN EARLY SPONDYLOARTHRITIS IN FINLAND
Authors: Paula Muilu, Vappu Rantalaiho, Hannu Kautiainen, Lauri Virta, Kari Puolakka
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background</h3> Disease-modifying anti-rheumatic drugs (DMARDs) are introduced for the treatment of spondyloarthritis (SpA) after failure of non-steroidal anti-inflammatory drugs (NSAIDs). In Finland, try out with a conventional synthetic DMARD (csDMARD) is required before initiation of biologicals (bDMARD). The patients with DMARDs are eligible for a higher reimbursement for the cost of medication. Opioids are not recommended for arthritis pain. <h3>Objectives</h3> To report the current DMARD and pain medication use among newly-onset SpA patients in Finland. <h3>Methods</h3> From the nationwide reimbursement register maintained by the Social Insurance Institution of Finland we collected all incident adult patients with SpA (ICD-10 codes M45-46) between 2010-14 and divided them into two groups depending on whether bDMARDs were subsequently initiated (group B) or not (group A). Patients' drug purchases between 2009-15 were obtained from the Drug Purchase Register. Opioid use by these patients was evaluated one year before and after the index date (ID; the date when special reimbursement for antirheumatic drugs became effective), and compared to age, sex, and place of residence matched population controls. Intravenously administered bDMARDs (e.g. infliximab) were not included. <h3>Results</h3> We identified 3577 SpA patients, 23% of which started a self-injected bDMARD during the observation period. More of the patients in group B needed pain medication, prednisolone, methotrexate, or other csDMARDs than sulphasalazine, which was more frequent in group A (table 1). Fifty-eight percent of the patients in group B started their bDMARD already within one year from ID (table 1). Overall, 29.8% of the SpA patients compared to 8.1% of the controls purchased opioids at least once during the year before ID. Patients' opioid purchases peaked during the last 3-month period before ID; risk ratios (RR) were 4.23 (95% confidence interval (CI) 3.63 to 4.84) and 6.23 (5.23 to 7.41) in patient groups A and B, respectively, compared to controls. SpA patients who had at least one opioid purchase during 12 months preceding the ID were 1.58 times more likely to start a bDMARD than those who did not purchase any opioids. <h3>Conclusion</h3> Only one of four early SpA patients in Finland were initiated a self-injected bDMARD during 2010-15. The use of opioids before SpA diagnosis appears to be nearly four times more common among SpA patients compared to population controls, and early opioid purchases may act as a surrogate marker for further bDMARD initiation. <h3>Disclosure of Interests</h3> Paula Muilu Grant/research support from: I have received a Congress trip from UCB Pharma and a Congress trip from MSD Finland outside the submitted work, Vappu Rantalaiho Grant/research support from: Dr. Rantalaiho has received a congress trip from Pfizer and a congress trip from Celegen outside the submitted work., Speakers bureau: Dr Rantalaiho reports a speaker's honorarium from Pfizer., Hannu Kautiainen: None declared, Lauri Virta: None declared, Kari Puolakka: None declared