Development of a Medicare Claims-Based Model to Predict Persistent High-Dose Opioid Use After Total Knee Replacement.

OBJECTIVE: To develop a claims-based model to predict persistent high-dose opioid use among patients undergoing total knee replacement (TKR). METHODS: Using Medicare claims (2010-2014), we identified patients ages ≥65 years who underwent TKR with no history of high-dose opioid use (mean >25 morphine milligram equivalents [MMEs]/day) in the year prior to TKR. We used group-based trajectory modeling to identify distinct opioid use patterns. The primary outcome was persistent high-dose opioid use in the year after TKR. We split the data into training (2010-2013) and test (2014) sets and used logistic regression with least absolute shrinkage and selection operator regularization, utilizing a total of 83 preoperative patient characteristics as candidate predictors. A reduced model with 10 prespecified variables, which included demographic characteristics, opioid use, and medication history was also considered. RESULTS: The final study cohort included 142,089 patients who underwent TKR. The group-based trajectory model identified 4 distinct trajectories of opioid use (group 1: short-term, low-dose; group 2: moderate-duration, low-dose; group 3: moderate-duration, high-dose; and group 4: persistent high-dose). The model predicting persistent high-dose opioid use achieved high discrimination (receiver operating characteristic area under the curve [AUC] 0.85 [95% confidence interval (95% CI) 0.84-0.86]) in the test set. The reduced model with 10 predictors performed equally well (AUC 0.84 [95% CI 0.84-0.85]). CONCLUSION: In this cohort of older patients, 10.6% became persistent high-dose (mean 22.4 MME/day) opioid users after TKR. Our model with 10 readily available clinical factors may help identify patients at high risk of future adverse outcomes from persistent opioid use after TKR.

Defining Pain That Does Not Interfere With Activities Among Rheumatoid Arthritis Patients.

OBJECTIVE: The objectives of this study were to: 1) characterize the distribution of noninterfering pain (defined as the pain intensity level at which individuals can function without interference) across different aspects of life among patients with rheumatoid arthritis (RA), and 2) identify clinical characteristics associated with differing levels of noninterfering pain. METHODS: Patients with RA in FORWARD, The National Databank for Rheumatic Diseases completed 8 items from the Patient-Reported Outcomes Measurement Information System (PROMIS) pain interference item bank that asked about interference with activities. If subjects reported pain interference, they were asked, "At what level would pain no longer interfere with this activity?" on a scale of 0 to 10. Subjects were also asked, "At what level of pain would you be able to do everything you want to do?" Multiple linear regression analyses examined associations between clinical characteristics and noninterfering pain. RESULTS: A total of 3,949 patients with RA completed the questionnaires. Pain interference was most common for daily activities and least common for ability to concentrate. The mean ± SD level at which pain no longer interfered with activities ranged from 2.7 ± 2.1 for ability to fall/stay asleep to 3.1 ± 2.0 for social activities. Overall, the mean ± SD threshold for noninterfering pain was 2.8 ± 1.9. The mean ± SD level of pain at which patients could do everything they wanted to do was 2.3 ± 1.9. More severe pain intensity was associated with higher noninterfering pain. CONCLUSION: The mean pain level that did not interfere with activities was 3. High pain intensity was associated with high self-reported noninterfering pain.

Association of Preoperative Opioid Use With Mortality and Short-term Safety Outcomes After Total Knee Replacement.

Importance: Prescription opioid use is common among patients with moderate to severe knee osteoarthritis before undergoing total knee replacement (TKR). Preoperative opioid use may be associated with worse clinical and safety outcomes after TKR. Objective: To determine the association of preoperative opioid use among patients 65 years and older with mortality and other complications at 30 days post-TKR. Design, Setting, And Participants: This cohort study used claims data from January 1, 2010, to December 31, 2014, from a random sample of US Medicare enrollees 65 years and older who underwent TKR. Based on opioid dispensing in 360 days prior to TKR, patients were classified as continuous (≥1 opioid dispensing in each of the past 12 months) or intermittent (any dispensing of opioids in the past 12 months but not continuous use) opioid users or as opioid-naive patients (no opioids dispensed in the past 12 months). Data analyses were conducted from October 3, 2017, to November 8, 2018. Main Outcomes and Measures: Primary outcomes included in-hospital mortality and 30-day post-TKR mortality, hospital readmission, and revision operation. Secondary safety outcomes at 30 days post-TKR included opioid overdose and vertebral and nonvertebral fracture. Multivariable Cox proportional hazards models estimated hazard ratios (HRs) and 95% CIs. Results: Of 316 593 patients (mean [SD] age, 73.9 [5.8] years; 214 677 [67.8%] women) who underwent TKR, 22 895 (7.2%) were continuous opioid users, 161 511 (51.0%) were intermittent opioid users, and 132 187 (41.7%) were opioid naive. In-hospital mortality occurred in 276 patients (0.09%). At 30 days post-TKR, 828 patients (0.26%) died, 16 786 patients (5.30%) had hospital readmission, and 921 patients (0.29%) had a revision operation. All primary and secondary outcomes occurred more frequently among continuous opioid users compared with opioid-naive patients. Compared with opioid-naive patients and after adjusting for demographic characteristics, combined comorbidity score, number of different prescription medications, and frailty, continuous opioid users had greater risk of revision operations (HR, 1.63; 95% CI, 1.15-2.32), vertebral fractures (HR, 2.37; 95% CI, 1.37-4.09), and opioid overdose (HR, 4.82; 95% CI, 1.36-17.07) at 30 days post-TKR. However, after adjusting covariates, there were no statistically significant differences in in-hospital (HR, 1.18; 95% CI, 0.73-1.90) or 30-day (HR, 1.05; 95% CI, 0.73-1.51) mortality between continuous opioid users and opioid-naive patients. Conclusions and Relevance: After adjusting for baseline risk profiles, including comorbidities and frailty, continuous opioid users had a higher risk of revision operations, vertebral fractures, and opioid overdose at 30 days post-TKR but not of in-hospital or 30-day mortality, compared with opioid-naive patients. These results highlight the need for better understanding of patient characteristics associated with chronic opioid use to optimize preoperative assessment of overall risk after TKR.

Association of Geography and Access to Health Care Providers With Long-Term Prescription Opioid Use in Medicare Patients With Severe Osteoarthritis: A Cohort Study.

OBJECTIVE: To evaluate the variation in long-term opioid use in osteoarthritis (OA) patients according to geography and health care access. METHODS: We designed an observational cohort study among OA patients undergoing total joint replacement (TJR) in the Medicare program (2010 through 2014). The independent variables of interest were the state of residence and health care access, which was quantified at the primary care service area (PCSA) level as categories of number of practicing primary care providers (PCPs) and categories of rheumatologists per 1,000 Medicare beneficiaries. The percentage of OA patients taking long-term opioids (≥90 days in the 360-day period immediately preceding TJR) within each PCSA was the outcome variable in a multilevel, generalized linear regression model, adjusting for case-mix at the PCSA level and for policies, including rigor of prescription drug monitoring programs and legalized medical marijuana, at the state level. RESULTS: A total of 358,121 patients with advanced OA, with a mean age of 74 years, were included from 4,080 PCSAs. The unadjusted mean percentage of long-term opioid users varied widely across states, ranging from 8.9% (Minnesota) to 26.4% (Alabama), and this variation persisted in the adjusted models. Access to PCPs was only modestly associated with rates of long-term opioid use between PCSAs with highest (>8.6) versus lowest (<3.6) concentration of PCPs (adjusted mean difference 1.4% [95% confidence interval 0.8%, 2.0%]), while access to rheumatologists was not associated with long-term opioid use. CONCLUSION: We note a substantial statewide variation in rates of long-term treatment with opioids in OA, which is not fully explained by the differences in access to health care providers, varying case-mix, or state-level policies.