Effect of high-dose glucocorticoids on persistent opioid use 3 to 12 months after primary total hip or knee arthroplasty. Protocol for a target trial emulation using observational data from Danish registries

BackgroundPersistent postsurgical pain and opioid use after primary total hip and knee arthroplasty (THA and TKA) have major consequences for the patient and for society. High-dose perioperative treatment with glucocorticoids reduces inflammation and acute pain, both of which are associated with persistent postsurgical pain. We therefore hypothesise that routine treatment with glucocorticoids reduces the number of patients with persistent opioid use. ObjectiveTo determine if perioperative glucocorticoids for primary THA or TKA surgery, relative to no glucocorticoids, decreases the number of patients taking opioids in the period from 3 to 12 months after surgery. DesignTarget trial emulation trial with data from Danish national registries. SettingAll departments of orthopaedic surgery in Denmark, from 1 January 2010 to 31 December 2020. ParticipantsPatients with primary osteoarthritis undergoing primary THA or TKA, excluding presurgical users of glucocorticoids or insulin because these patients do not always receive the intervention. InterventionA single high-dose glucocorticoids ([≥]125 mg methylprednisolone or [≥]24 mg dexamethasone) after induction of anaesthesia. ComparatorNo glucocorticoids during surgery. AllocationPatients operated at departments where treatment with high-dose glucocorticoids was standard of care at the time of surgery constitute the treatment arm, while patients operated at departments where high-dose glucocorticoids was not used serve as controls. Thus, all patients will be analysed according to their allocation, regardless of whether they received the treatment or not. Main outcome measuresThe primary outcome is number of persistent opioid users, defined as patients who redeem a prescription within at least two of the last three quarters during the first postsurgical year. The primary safety outcome is number of days alive and out of hospital within 90 days after surgery. ExpectationsThese results will provide important evidence for or against the use of perioperative glucocorticoids in total hip and knee arthroplasty.