Use of Analgesic and Anti-Inflammatory Medicines before and after Initiation of Biological Disease-Modifying Antirheumatic Drugs for Rheumatoid Arthritis

Abstract

Background. Rheumatoid arthritis (RA) is an inflammatory condition that causes joint damage and is associated with pain. The biological disease-modifying antirheumatic drugs (bDMARDs) for RA are linked to additional therapeutic benefits as they suppress the inflammatory process, which in turn prevents joint erosion and reduces pain. Thus, the use of bDMARDs has the potential to reduce the need for other analgesic and anti-inflammatory therapies for RA. The aim of this study was to examine the analgesic and anti-inflammatory use around the initiation of bDMARDs. Methods. A cohort study was conducted using a 10% random sample of the population dispensing medicines under the Australian Pharmaceutical Benefits Scheme. People who initiated the first bDMARD for RA between 2014 and 2018 were included. The proportion who received any analgesic or anti-inflammatory, including nonsteroidal anti-inflammatory drugs, opioids, or glucocorticoids, in the twelve months prior to and post-bDMARD initiation was determined and compared using regression models. Results. There were 18,360 persons in the cohort, with a mean age of 55 years, and 69% were women. The use of any analgesic or anti-inflammatory in both tumor necrosis factor inhibitor (TNFi) and non-TNF initiators increased prior to initiation of bDMARD–from 43% to 52% in TNFi and from 52% to 63% in non-TNF initiators. In both groups, overall use decreased significantly post initiation to 37% and 42% in TNFi and non-TNF initiators, respectively ($p<0.0001$). bDMARD initiation was associated with lower use of glucocorticoid therapy, but there was no decreasing effect on opioid use. Conclusion. While the use of any analgesic or anti-inflammatories decreased post-initiation of bDMARDs for RA, more than one-third of people were dispensed analgesic or anti-inflammatory agents twelve months post initiation. Ongoing review of the need for analgesic and glucocorticoids appears warranted, with assessment of nonpharmacological approaches to support pain management.