Opioid utilization and opioid-related adverse events in nonsurgical patients in US hospitals.

BACKGROUND: Recent studies in the outpatient setting have demonstrated high rates of opioid prescribing and overdose-related deaths. Prescribing practices in hospitalized patients are unexamined.

OBJECTIVE: To investigate patterns and predictors of opioid utilization in nonsurgical admissions to US hospitals, variation in use, and the association between hospital-level use and rates of severe opioid-related adverse events.

DESIGN, SETTING, AND PATIENTS: Adult nonsurgical admissions to 286 US hospitals.

MEASUREMENTS: Opioid exposure and severe opioid-related adverse events during hospitalization, defined using hospital charges and International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes.

RESULTS: Of 1.14 million admissions, opioids were used in 51%. The mean ± standard deviation daily dose received in oral morphine equivalents was 68 ± 185 mg; 23% of exposed received a total daily dose of ≥100 mg oral morphine equivalents. Opioid-prescribing rates ranged from 5% in the lowest-prescribing hospital to 72% in the highest-prescribing hospital (mean, 51% ± 10%). After adjusting for patient characteristics, the adjusted opioid-prescribing rates ranged from 33% to 64% (mean, 50% ± standard deviation 4%). Among exposed, 0.60% experienced severe opioid-related adverse events. Hospitals with higher opioid-prescribing rates had higher adjusted relative risk of a severe opioid-related adverse event per patient exposed (relative risk: 1.23 [1.14-1.33] for highest-prescribing compared with lowest-prescribing quartile).

CONCLUSIONS: The majority of hospitalized nonsurgical patients were exposed to opioids, often at high doses. Hospitals that used opioids most frequently had increased adjusted risk of a severe opioid-related adverse event per patient exposed. Interventions to standardize and enhance the safety of opioid prescribing in hospitalized patients should be investigated.