Nonopioid analgesic use in older patients admitted for orthopedic rehabilitation.

Background: Multimodal analgesia (MMA) combines opioids with nonopioid analgesics (NOAs) to mitigate opioid-related adverse events and development of opioid use disorders. Although MMA has become the standard for orthopedic perioperative pain management, guidance is less clear for the approximately 15% of patients who go on to require inpatient orthopedic rehabilitation (IOR) postoperatively. The IOR population tends to be older and frailer and hence likely more vulnerable to adverse events. Little research has been done to shed light on how NOAs are used in this population.

Objective: To characterize NOA prescribing in older versus younger adults during IOR admissions and to determine predictors of NOA prescribing in an older IOR population.

Design: Retrospective case-control study.

Setting: Two IOR wards at an academic rehabilitation hospital in Toronto, Canada.

Patients: All patients aged ≥50 years admitted for an orthopedic indication between November 2019 and June 2021; the patients aged <65 group was included for comparative characterization of NOA prescribing versus older peers.

Interventions: Not applicable.

Main outcome measures: Medication use and adverse events, pain, and rehabilitation outcomes such as the Functional Independence Measure, discharge destination, and length of stay.

Results: A total of 643 patient encounters were included; 48.2% used NOA. Age (odds ratio [OR]: 0.97; confidence interval [CI]: 0.95-0.99, p < .001) and prior NOA use (OR: 3.15; CI: 2.0-4.9, p < .001) were associated with NOA prescribing. Other positively associated factors included body mass index, psychiatric history, elective surgery, and admission from a specific referring hospital. Adverse events between NOA users and nonusers were similar.

Conclusions: NOA prescribing is heterogeneous and declines with age in IOR. This points to an opportunity to explore integrating NOA into opioid-sparing MMA protocols tailored to older IOR patients, along with further study of the safety and benefit of these regimens.