Abuse, Opioid

Elderly patients who underwent lower extremity arthroplasty in Drum Tower Hospital Affiliated to Nanjing University Medical School from September 2020 to March 2021 were selected and followed up for postoperative pain assessment using the numerical rating scale NRS. The elderly osteoarthritis patients selected were all caused by joint degeneration rather than fractures or necrosis caused by other reasons. They were performed operations by the same group of doctors and operation method. All patients signed informed consent and were authorized by the ethics committee of Drum Tower Hospital Affiliated to Nanjing University Medical School (Nanjing, China, No. 2019-270-02). Inclusion criteria: (1) Age ≥ 65 years old; (2) American Society of Anesthesiologists (ASA) classification II–III; (3) Patients undergoing lower extremity arthroplasty; (4) Operation duration ≥ 60 min; (5) Patients recorded in electronic medical record system; (6) Patients agreed to participate in the study and signed the informed consent. Exclusion criteria: (1) With gene deficiency disease; (2) Having history of opioid abuse; (3) Using drugs that induce or inhibit liver isoenzymes (such as carbamazepine, quinidine, ketoconazole, etc.) in 4 weeks before operation; (4) Combined with peripheral neuropathy and psychiatric history, chronic pain and long-term opioid use history; (5) With poor body conditions affecting the perioperative pain evaluation; (6) Patients can’t cooperate and communicate with.
The patient's NRS score being ≥ 4 on the 90th day after operation was identified as having severe CPSP. A total of 10 patients were judged to have severe CPSP (group A). 10 patients hospitalized in the same period without chronic postsurgical pain (NRS score = 0 on the 90th day after operation) were randomly selected as the control group (group B).

We used Medicaid reimbursement claims data obtained from the Indiana Family and Social Services Administration. We extracted patients who were diagnosed with an OUD between January 2018 and March 2019 (Supplementary Fig. S1) and enrolled in Medicaid for the entire duration. The time interval was partly chosen because the State of Indiana initiated the 1115 SUD Waiver Implementation Plan, which provided full coverage of opioid treatment program services to Medicaid eligible in Indiana, including daily administration of methadone.⁷ A total of 1.88 million people were covered by Indiana Medicaid for the study period. From this population, we also extracted patients diagnosed with problematic use of opioids, that is, those diagnosed with opioid abuse, opioid use, opioid dependence, and/or patients who had an emergency room visit or hospitalization with an opioid-related poisoning within the study period (ICD-10 diagnosis codes F11.XXX and T40.XXXX). We excluded codes F11.11 and F11.21, which correspond to opioid abuse or dependence in remission (see Supplementary Table S1). These codes have been previously used to effectively detect illicit substance use as a behavior.^{8 (link)} Based on demographic reporting, we categorized sex (male and female) and race/ethnicity (White and non-White). The group of non-White includes those who identified their race/ethnicity group as Black, Hispanic, and Other (individuals who do not identify as White, Black, or Hispanic). Race/ethnicity was dichotomized due to the relatively small sample size of the non-White group.
For each extracted patient, we used the ICD-10 Procedure Coding System codes for claims classification to identify their sequence of treatment utilization (see Supplementary Table S2). Procedure codes were aggregated into four categories (1) detoxification, (2) psychosocial services that include individual or group counseling and psychotherapy, (3) medication-assisted treatment that includes agonist medication (methadone or buprenorphine) or antagonist medication (naltrexone), and (4) comprehensive treatment that includes a combination of agonist or antagonist meditation with one type of psychosocial service.
We verified the significance on difference in the proportion of patients receiving treatment between population subgroups using a two-proportion Z-test. All statistical tests were two-sided, and p<0.05 was used for statistical significance.

Patients completed surveys to evaluate symptoms including depression, anxiety, and functional status. The National Comprehensive Cancer Network (NCCN) Distress Thermometer and Problem List and Functional Activity Scale (FAS) [11 (link)–14 (link)] surveys were collected at each visit (every 3-to-4 weeks). Patients were also asked to complete the following surveys every 3 months for up to 1 year: European Organization for Research and Treatment of Cancer (EORTC), Quality of Life of Cancer Patients (QLC-C30), Quality of Life-Lung Cancer 13 (QLQ-LC-13) [15 (link), 16 (link)], and the Hospital Anxiety and Depression Scale (HADS) [17 (link)]. For EORTC, the scores range from 0 to 100 with higher scores indicating a healthy level of functioning and lower scores indicating a high level of symptomatology. The HADS is a 14-item scale with seven items each for anxiety and depression subscales. Scoring for each item ranges from 0 to 3. A subscale score ≥ 8 denotes anxiety or depression [18 (link)]. At baseline only, patients completed the Screener and Opioid Assessment for Patients with Pain-Revised (SOAPP-R) to assess opioid abuse risk [10 (link), 19 (link)]. Patient acceptability questions regarding patient opinions within the Onco-Pall model were completed once at the 3-month time point. This consisted of five questions to assess patient preferences regarding palliative care appointments, including timing, location, length of visit, and open-ended feedback. The caregivers were asked to complete the Supportive Care Needs Survey–Patients & Caregivers (SCNC-P&C) at baseline and then every 3 months for up to 1 year [20 (link), 21 (link)].