The Preoperative Patient-Reported Outcomes Measurement Information System (PROMIS)-10 Global Mental Health T-Score: An Independent Predictor of Immediate Post-Surgical Outcomes Following Elective Total Knee Arthroplasty.

Background: Mental illness is a known risk factor for poor postoperative outcomes following total knee arthroplasty (TKA); however, a diagnosed mental illness does not always reflect the current state of a patient's mental health. Using the preoperative Patient-Reported Outcomes Measurement Information System (PROMIS)-10 Mental Health T-score (MHT), the purpose of this study was to understand the association between mental health and a patient's immediate inpatient recovery pattern following TKA.

Methods: This was a retrospective study of patients undergoing elective primary TKA. Patients were grouped based on their MHT score (Above Average [AA] > 50, Average [A] 40 to 50, Below Average [BA] < 40). Postsurgical parameters included inpatient opioid consumption, pain reporting, functional measures, and discharge disposition.

Results: A total of 2,740 patients were included in this study (AA 55.8%, A 35.4%, BA 8.8%). Multivariate modeling demonstrated that an MHT score below 40 was an independent risk factor for opioid consumption, pain reporting, discharge disposition, ambulation distance, and timed-up-and-go performance. A diagnosed mental illness was not associated with poor outcomes.

Conclusion: The MHT can be used as a preoperative screening tool that can identify an at-risk group not previously described. An MHT< 40 was associated with poor immediate postoperative outcomes.