Injection-site burning and stinging in patients with rheumatoid arthritis using injectable biologics

Some patients with rheumatoid arthritis (RA) who receive injectable biologics experience injection-site burning and stinging (ISBS); however, the prevalence of ISBS in the general RA population is unknown and may impact preference for an injectable biologic. This study assessed the prevalence of ISBS and associated comorbidities in patients with RA who receive injectable biologics. The physician and patient survey consisted of a retrospective chart review and a prospective assessment. In the former, each participating US rheumatologist reviewed the medical records of five randomly selected RA patients receiving an injectable biologic. In the prospective assessment, each rheumatologist was asked to report data based on interviews with up to 50 RA patients currently treated with an injectable biologic, who were asked whether they had ISBS during or after their most recent injection. Data were analyzed for 504 patients in the retrospective chart review and 3326 patients in the prospective assessment; data were provided by 101 physicians. The overall prevalence of ISBS was 17% and 58% in the retrospective chart review and prospective analyses, respectively. Out of the 1939 prospectively assessed patients who experienced at least some ISBS, 429 (22%) rated the level of ISBS as moderate to severe (13% of total). Increased risk of ISBS was associated with female gender, fibromyalgia, depression, and more severe RA. The prevalence of ISBS is likely underestimated in many rheumatology practices. Specifically asking about it may identify patients who experience this side effect, provide a more accurate understanding of how significantly it affects them, and provide an opportunity for intervention in light of their preferences.