Frequency of and Factors Associated with Nonmedical Opioid Use Behavior among Patients with Cancer Receiving Opioids for Cancer Pain

Importance One of the main aims of research on nonmedical opioid use (NMOU) is to reduce the frequency of NMOU behaviors through interventions such as universal screening, reduced opioid exposure, and more intense follow-up of patients with elevated risk. The absence of data on the frequency of NMOU behavior is the major barrier to conducting research on NMOU. Objective To determine the overall frequency of and the independent predictors for NMOU behavior. Design, Setting, and Participants In this prognostic study, 3615 patients with cancer were referred to the supportive care center at MD Anderson Cancer Center from March 18, 2016, to June 6, 2018. Patients were eligible for inclusion if they had cancer and were taking opioids for cancer pain for at least 1 week. Patients were excluded if they had no follow-up within 3 months of initial consultation, did not complete the appropriate questionnaire, or did not have scheduled opioid treatments. After exclusion, a total of 1554 consecutive patients were assessed for NMOU behavior using established diagnostic criteria. All patients were assessed using the Edmonton Symptom Assessment Scale, the Screener and Opioid Assessment for Patients with Pain (SOAPP), and the Cut Down, Annoyed, Guilty, Eye Opener-Adapted to Include Drugs (CAGE-AID) survey. Data were analyzed from January 6 to September 25, 2020. Results A total of 1554 patients (median [interquartile range (IQR)] age, 61 [IQR, 52-69] years; 816 women [52.5%]; 1124 White patients [72.3%]) were evaluable for the study, and 299 patients (19.2%) had 1 or more NMOU behaviors. The median (IQR) number of NMOU behaviors per patient was 1 (IQR, 1-3). A total of 576 of 745 NMOU behaviors (77%) occurred by the first 2 follow-up visits. The most frequent NMOU behavior was unscheduled clinic visits for inappropriate refills (218 of 745 [29%]). Eighty-eight of 299 patients (29.4%) scored 7 or higher on SOAPP, and 48 (16.6%) scored at least 2 out of 4 points on the CAGE-AID survey. Results from the multivariate model suggest that marital status (single, hazard ratio [HR], 1.58; 95% CI, 1.15-2.18; P = .005; divorced, HR, 1.43; 95% CI, 1.01-2.03; P = .04), SOAPP score (positive vs negative, HR, 1.35; 95% CI, 1.04-1.74; P = .02), morphine equivalent daily dose (MEDD) (HR, 1.003; 95% CI, 1.002-1.004; P < .001), and Edmonton Symptom Assessment Scale pain level (HR, 1.11; 95% CI, 1.06-1.16; P < .001) were independently associated with the presence of NMOU behavior. In recursive partition analysis, single marital status, MEDD greater than 50 mg, and SOAPP scores greater than 7 were associated with a higher risk (56%) for the presence of NMOU behavior. Conclusions and Relevance This prognostic study of patients with cancer taking opioids for cancer pain found that 19% of patients developed NMOU behavior within a median duration of 8 weeks after initial supportive care clinic consultation. Marital status (single or divorced), SOAPP score greater than 7, higher levels of pain severity, and MEDD level were independently associated with NMOU behavior. This information will assist clinicians and investigators designing clinical and research programs in this important field.