Prescription opioid abuse and misuse: gap between primary-care investigator assessment and actual extent of these behaviors among patients with chronic pain.

Objectives: To compare the results of two open-label primary care-based studies that examined investigator assessment of patient risk for prescription opioid misuse, abuse, and diversion relative to patient self-reports and urine drug tests (UDTs).

Methods: Risk assessment data from two open-label, multicenter, primary care-based US studies in patients with chronic pain were compared.

Results: In one study (n = 1487), 54.4% of patients were at moderate, 24.8% at high, and 20.8% at low risk based on patients' self-reports at baseline on the Screener and Opioid Assessment for Patients with Pain®-Revised questionnaire. Investigators assigned 1.3% of patients as high risk despite 5.0% self-reporting prior illicit drug use and 15.3% with positive UDT(s) for an illicit drug at baseline. In the second study (n = 684), few patients were considered by investigators to be at high risk for misuse (1.6%), abuse (1.8%), or diversion (1.0%). However, 10.4% of patients reported prior illicit drug use; 23.4% had at least one abnormal baseline UDT; 60% of 537 patients reported on the Self-Reported Misuse, Abuse, and Diversion questionnaire they took more opioids than prescribed; and 10.9% reported chewing/crushing opioids in the past. Of patients completing the Current Opioid Misuse Measure, 40.6% were classified as having aberrant behaviors.

Conclusion: A comparison of risk assessment across two studies indicates a tendency for investigators to assess patients as lower risk for opioid-related aberrant behaviors despite a significant proportion self-reporting aberrant behavior and/or presenting with illicit UDTs. These consistent findings underline the importance of appropriate implementation of objective measures and self-reporting tools when evaluating risk in patients.

Clinical Trial Registration: www.clinicaltrials.gov identifiers: NCT00640042 and NCT01179191.