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

Abstract
Recent studies in the outpatient setting have demonstrated high rates of opioid prescribing and overdose-related deaths. Prescribing practices in hospitalized patients are unexamined. 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. Adult nonsurgical admissions to 286 US hospitals. 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. 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). 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.