30-Day Potentially Avoidable Readmissions Due to Adverse Drug Events.

OBJECTIVE: To analyze the patterns of potentially avoidable readmissions due to adverse drug events (ADEs) to identify the most appropriate risk reduction interventions.

METHODS: In this observational study, we analyzed a random sample of 534 potentially avoidable 30-day readmissions from 10,275 consecutive discharges from the medical department of an academic hospital. Readmissions due to ADEs were reviewed to identify the causative drugs and the severity and interventions to prevent them.

RESULTS: Seventy cases (13.1%) of readmission were partially or predominantly due to ADEs, of which, 58 (82.9%) were serious ADEs. Overall, 65 (92.9%) of the ADEs have been confirmed to be preventable. Inappropriate prescribing was identified as the cause of ADE in 34 cases (48.6%) mainly involving diuretics, analgesics, or antithrombotics: misprescribing n = 19 (27.1%), underprescribing n = 8 (11.4%), and overprescribing n = 7 (10.0%). The remaining half of preventable ADEs (n = 36; 51.4%) were related to suboptimal patient monitoring/education, such as adherence issues (n = 6; 8.6%) or lack of monitoring (n = 31; 44.3%). In 64 cases (91.4%), the readmission could have been potentially prevented by better monitoring for drug efficacy/disease control, or for predictable side effect. Thirty-three (97.1%) of the 34 ADEs due to inappropriate prescribing could have also been prevented by better monitoring.

CONCLUSIONS: Adverse drug events accounted for approximately 13% of 30-day preventable readmissions. A half were due to prescription errors involving mainly diuretics, analgesics, or antithrombotics, and the other half were due to suboptimal patient monitoring/education, most frequently with antineoplastics. Both these avoidable causes may represent opportunities to reduce the total drug-related adverse events.