CORR Insights®: NarxCare Scores Greater Than 300 Are Associated with Adverse Outcomes After Primary THA

Where Are We Now?

The study by Emara and colleagues [4] focuses on the problems that arise when opioid, sedative, and stimulant drugs are misused by patients with end-stage hip osteoarthritis. As we think about this problem, though, we have to remember that inappropriate use often begins with physician prescription patterns; in general, our patients can’t misuse drugs that we don’t prescribe to them. All the same, the misuse epidemic continues to be a major public health problem in the United States [5], and patients with end-stage hip and knee osteoarthritis certainly experience the fallout of this epidemic [2]. Understanding the implications of misuse of these potent medications is critically important if we are to develop and implement interventions that will reduce their harms.

The current study certainly is not the first to show the adverse effects of taking opioids on outcomes of THA patients. However, it is worthy of our attention for two main reasons. First, the data used in this study are recent, highlighting the continued high use of opioids among end-stage hip osteoarthritis patients undergoing THA. Second, the substantial effect these medications have on postoperative healthcare utilization is further explored using a scalar measure, the widely available NarxCare score, which allows for more accurate quantitative assessment than previously had been possible. The authors found that a threshold of 300 or higher on the NarxCare score was associated with at least a doubling of the odds of 90-day all-cause readmission, procedure-related readmission, length of stay > 2 days, and non-home discharge compared with those below this threshold. The NarxCare score seems to provide surgeons with a more precise assessment of patients’ use of opioid, sedative, and stimulant drugs than we’ve had before; it’s a good tool, for an important job. With that in mind, I believe that surgeons should pay close attention to this scalar score when screening patients before surgery.

Where Do We Need To Go?

This paper highlights the importance of having the appropriate objective measures, such as the NarxCare score, to quantify opioid use among patients. By studying the relationship of this score to healthcare utilization, the authors identified thresholds that could provide surgeons and healthcare institutions with an easy way to identify patient subpopulations at greater risk of adverse outcomes. While an important finding, having such a threshold runs the risk of bluntly categorizing patients into two groups: those at high risk and those who are not. But in reality, a THA patient with a preoperative NarxCare score of 300 is not at significantly higher risk of adverse outcomes than the patient with a preoperative score of 299. Future studies might address the need to come up with a more nuanced and less categorical approach to examining the impact that such as score may have on healthcare utilization.

In addition, with the current study focused on patients who had THA, it provides only a partial assessment of the impact of NarxCare score. Since this study is a retrospective administrative database analysis, the authors did not examine outcomes of patients who did not have a THA. In clinical practice, however, knowing one’s opioid profile is likely to impact the decision-making process and may result in postponing or canceling THA. Patients who canceled their surgery would not have been captured in the current study, and those who postponed were likely captured after they have postponed their surgery to address their opioid use. As such, the implications of the NarxCare score on healthcare utilization in the current study may be an underestimate of the overall impact of implementing this score in clinical practice. Having said that, it is not clear to what extent other metrics of opioid use (such as the number of prescriptions) are already being implemented in clinical practice and affecting delays or cancellations of surgery, and how these would compare to the NarxCare score. A more comprehensive and accurate assessment of the NarxCare score and thresholds in clinical practice are needed before such a score is adopted in decision-making.

How Do We Get There?

The ultimate goal of this and other related studies is to better manage the postoperative care of THA patients who are using opioid, sedative, and stimulant drugs. With the NarxCare score widely available, it provides an outstanding opportunity to achieve this goal and improve the results patients have after surgery, as well as their health overall. However, a number of additional evaluation studies are warranted. The NarxCare score is a continuous variable, and analyzing it as such provides patients and surgeons with a more accurate assessment of the relative increase in risk of postoperative healthcare utilization associated with a particular NarxCare score. A randomized clinical trial randomizing patients who are considering THA to receiving either the Narxcare score or standard of care is needed to fully understand the impact of this score on decision-making and outcomes. The NarxCare arm may further include subsets with different methods of presenting the score to the patient-surgeon dyads. For example, the increased risk may be presented as a number or as a visual (a bar chart or a speedometer). Such a study would be feasible and would determine how the availability of the NarxCare score will affect the quality of decision-making and changes in rates of surgery, delays, and cancellations.

The wide availability of the NarxCare score may also present important implementation challenges across health systems that need to be addressed. Recent reports of underreporting of opioid drug use among patients with hip and knee osteoarthritis may affect the accuracy of the NarxCare score, and subsequently the accuracy of flagging the subset of patients who might benefit from further counseling [1, 6]. With misuse rates varying widely across urban and rural areas, and by race and ethnicity [3, 7], health systems should take these factors into account when developing interventions.

Finally, as we think about the way forward, we need to recognize that the NarxCare score only quantifies the impact of pre-THA use of opioids. Indeed, THA is a painful procedure and patients undergoing this procedure are likely to be prescribed opioids or other narcotic pain medications during their recovery. Therefore, physician prescription habits and institutional protocols for use of such medications needs to be factored into any interventions that may be developed to appropriately address patients in need of further management and counseling regarding their opioid use.