Persistent postoperative opioid use after total hip or knee arthroplasty: A systematic review and meta-analysis.

PURPOSE: To identify the proportion of patients with continued opioid use after total hip or knee arthroplasty. METHODS: This systematic review and meta-analysis searched Embase, MEDLINE, the Cochrane Central Register of Controlled Trials, and International Pharmaceutical Abstracts for articles published from January 1, 2009, to May 26, 2021. The search terms (opioid, postoperative, hospital discharge, total hip or knee arthroplasty, and treatment duration) were based on 5 key concepts. We included studies of adults who underwent total hip or knee arthroplasty, with at least 3 months postoperative follow-up. RESULTS: There were 30 studies included. Of these, 17 reported on outcomes of total hip arthroplasty and 19 reported on outcomes of total knee arthroplasty, with some reporting on outcomes of both procedures. In patients having total hip arthroplasty, rates of postoperative opioid use at various time points were as follows: at 3 months, 20% (95% CI, 13%-26%); at 6 months, 17% (95% CI, 12%-21%); at 9 months, 19% (95% CI, 13%-24%); and at 12 months, 16% (95% CI, 15%-16%). In patients who underwent total knee arthroplasty, rates of postoperative opioid use were as follows: at 3 months, 26% (95% CI, 19%-33%); at 6 months, 20% (95% CI, 17%-24%); at 9 months, 23% (95% CI, 17%-28%); and at 12 months, 21% (95% CI, 12%-29%). Opioid naïve patients were less likely to have continued postoperative opioid use than those who were opioid tolerant preoperatively. CONCLUSION: Over 1 in 5 patients continued opioid use for longer than 3 months after total hip or knee arthroplasty. Clinicians should be aware of this trajectory of opioid consumption after surgery.

Proposed guidance on cost-avoidance studies in pharmacy practice.

PURPOSE: Cost-avoidance studies of pharmacist interventions are common and often the first type of study conducted by investigators to quantify the economic impact of clinical pharmacy services. The purpose of this primer is to provide guidance for conducting cost-avoidance studies pertaining to clinical pharmacy practice. SUMMARY: Cost-avoidance studies represent a paradigm conceptually different from traditional pharmacoeconomic analysis. A cost-avoidance study reports on cost savings from a given intervention, where the savings is estimated based on a counterfactual scenario. Investigators need to determine what specifically would have happened to the patient if the intervention did not occur. This assessment can be fundamentally flawed, depending on underlying assumptions regarding the pharmacists' action and the patient trajectory. It requires careful identification of the potential consequence of nonaction, as well as probability and cost assessment. Given the uncertainty of assumptions, sensitivity analyses should be performed. A step-by-step methodology, formula for calculations, and best practice guidance is provided. CONCLUSIONS: Cost-avoidance studies focused on pharmacist interventions should be considered low-level evidence. These studies are acceptable to provide pilot data for the planning of future clinical trials. The guidance provided in this article should be followed to improve the quality and validity of such investigations.