Orthopaedic corticosteroid injections and risk of acute coronary syndrome: A cohort study

Abstract

Abstract Background: Corticosteroid injections (CSI) are a common treatment for arthritis and other musculoskeletal conditions. Aim: To determine whether there is an increased incidence of an acute coronary syndrome, (ACS) following intra-articular and soft tissue CSI. Design and Setting: Cohort study in an urban primary care orthopaedic clinic. Method: Data were reviewed from all patients, aged 50 years or older, seen by orthopaedic specialists between April 2012 and December 2015; including CSI, hospitalisation in the week following the orthopaedic visit and cardiovascular risk factors. The incidence of an ACS-associated hospitalisation was compared between visits in which patients received CSIs and visits in which patients did not. Results: 60,856 orthopaedic visits were reviewed (22,131 individual patients). The mean age was 70.9 years (standard deviation 10.8), and 66.5%, women. Injections were administered in 3,068 visits (5.1%). In the week following the visit, there were 25 ACS hospitalisations (41 per 100,000 visits); seven events were after visits with an injection, and 18 after non-injection visits. Patients who had received an injection were more likely to experience a subsequent ACS (227 versus 31 events per 100,000 visits, odds ratio 7.3; 95% confidence interval 2.8-19.1). The association between receiving a corticosteroid injection and ACS remained similar when the analysis was restricted to subgroups defined by age, sex and cardiovascular risk factors. Conclusions: Corticosteroid injections for musculoskeletal conditions may substantially increase the risk of ACS in the week following the injection. Whilst the absolute risk of ACS is small the effect size appears to be clinically significant.