THU0624 UNDERSTANDING ETHNIC DIFFERENCES IN THE UTILIZATION OF NONSTEROIDAL ANTI-INFLAMMATORY DRUGS FOR OSTEOARTHRITIS
Authors: Ernest Vina, Michael Hannon, Jazmin Dagnino, C. Kent Kwoh
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background:</h3> The prevalence of arthritis-attributable activity limitation, work limitation and severe pain are significantly higher among Hispanics than among non-Hispanic Whites (NHWs) in the US. While Hispanics are less likely to report regular use of nonsteroidal anti-inflammatory drugs (NSAIDs), reasons for this decreased NSAID use are unknown. It is also unclear whether there are ethnic differences in the use of both over-the-counter (OTC) and prescription NSAIDs. <h3>Objectives:</h3> To determine: 1) if there are ethnic differences in the use of OTC and prescription oral NSAIDs for knee/hip osteoarthritis (OA); 2) if there are differences in familiarity with and perceptions of efficacy and risk of NSAIDs between Hispanics and NHWs; and 3) if patient attitudes/beliefs about NSAIDs mediate observed ethnic differences in the use of NSAIDS for OA. <h3>Methods:</h3> Participants ≥50 years of age with chronic frequent pain due to knee/hip OA completed structured interviews. Data on sociodemographic characteristics, clinical information, actual use of oral NSAIDs for OA treatment (last 6 months), and familiarity with NSAIDs (3 items, yes/no response) were collected. Perceptions of efficacy (4 items) and risk (3 items) of NSAIDs were evaluated using five-category ordinal response scale questions. Responses were averaged, with higher values indicating higher perception of efficacy/risk. Fisher's exact or Wilcoxon-Mann-Whitney tests were conducted to determine if knowledge and perceptions about NSAIDs differed by ethnicity. Multivariable logistic regression models were built to determine if ethnic differences in NSAID use were mediated by knowledge and perceptions about the medication. <h3>Results:</h3> Among knee/hip OA patients, Hispanics (n=130), in comparison to NHWs (n=204), were younger (mean age 61.8 vs. 65.7) and less likely to have an annual income of ≥$40K (21.6% vs. 56.5%). Hispanics, compared to NHWs, had lower odds of using an OTC NSAID (OR 0.57, 95% CI 0.36-0.90) but greater odds of using a prescription NSAID (OR 1.66, 95% CI 1.04-2.64) for OA. Hispanics, compared to NHWs, were also less likely to ever hear about OTC and prescription oral NSAID to treat OA or have a good understanding of either oral NSAID type as a treatment for OA (Table 1). Mean [SD] perceived efficacy of OTC and prescription oral NSAIDs were slightly lower among Hispanics than NHWs (2.91 [0.98] vs. 3.12 [0.88], p=0.0565; 3.03 [1.02] vs. 3.34 [0.87], p=0.0047; respectively). Mean [SD] perceived risk of prescription NSAIDs was lower among Hispanics than NHWs (2.44 [1.03] vs. 2.82 [1.01], p=0.0012). After adjustment for all familiarity with OTC NSAIDs questions, and perceived efficacy and risk of OTC oral NSAIDs scores, the association between OTC NSAID use and ethnicity was attenuated and no longer significant (OR 1.01, 95%CI 0.54-1.89). After adjustment for familiarity with and perceptions of efficacy and risk of prescription NSAIDs, the association between prescription NSAID use and ethnicity remained significant (OR 2.62, 95%CI 1.51-4.54). <h3>Conclusion:</h3> Among patients with knee or hip OA, Hispanics were less likely than NHWs to utilize an OTC oral NSAID as treatment for arthritis. They were also less familiar with the use of NSAIDs for OA treatment and less likely to believe in their efficacy. Patient familiarity and perceptions of OTC oral NSAIDs may mediate ethnic differences in the use of NSAIDs for knee/hip OA. <h3>Disclosure of Interests:</h3> Ernest Vina Grant/research support from: Astrazeneca, Consultant for: Astrazeneca, Michael Hannon Employee of: Pinney Associates, Jazmin Dagnino: None declared, C. Kent Kwoh Grant/research support from: Abbvie, EMD Serono, Consultant for: Astellas, EMD Serono, Thusane, Express Scripts, Novartis