Preoperative NarxCare overdose risk scores greater than 100 are associated with worse PROMs improvements and dissatisfaction after primary THA

Abstract Introduction The NarxCare Overdose Risk Score (ORS) is a weighted measure of patient-specific prescription drug use. In patients undergoing primary total hip arthroplasty (THA), this study aimed to evaluate (1) the trend of the ORS from preoperative to 1-year postoperatively, and (2) the association of preoperative ORS with achievement of clinically meaningful improvements in patient reported outcome measures (PROMs), and satisfaction at 1-year. Methods All patients who underwent primary unilateral elective THA at a USA tertiary healthcare system from January 2016-December 2022 were eligible. Patients with incomplete PROMs or missing baseline NarxCare ORS were excluded, leading to the inclusion of 5,424 patients. Multivariable regression models were used to assess the association between ORS and 1-year PROMs, including achievement of the minimum clinically important difference (MCID) and Patient Acceptable Symptom State (PASS) for the Hip Disability and Osteoarthritis Outcome Score (HOOS) subdomain scores, as well as satisfaction. Results Preoperatively, 46.1% ( n = 2501) had a NarxCare ORS of 0, 24.6% ( n = 1336) had scores between 100 and 199, and 16.2% ( n = 876) in the 200–299 range. After adjusting for confounding variables, a preoperative ORS of 100–199 was associated with failure to achieve MCID in HOOS Pain (OR 1.91;CI 1.32–2.77; p = 0.001), and HOOS JR (OR 1.54;1.10–2.15; p = 0.012). Preoperative ORS of 100–199 was also associated with failure to reach PASS threshold in HOOS Pain (OR 1.45;1.23–1.71; p < 0.001), PS (OR 1.47;1.22–1.75; p < 0.001) and JR (OR 1.26;1.08–1.49; p = 0.004), with the odds of failure continually increasing as the ORS increases. Patients with a preoperative ORS of 100–199 were 58% more likely to be dissatisfied at 1-year (OR 1.58;1.26–1.99; p < 0.001) compared to prescription drug use naïve patients. Conclusions Increasing preoperative NarxCare ORS, a measure of prescription drug use, is inversely associated with patient perceived improvement after THA. An ORS of just 100 may significantly decrease the chances of clinically meaningful improvements in hip pain and function, as well as satisfaction at 1-year. A multidisciplinary approach is warranted to mitigate the detrimental effects of sedatives, opioids, or stimulant drug use and surgeons may use this easily accessible score to guide a patient centered discussion regarding postoperative improvements. Level of evidence III.