Abstract:
Aims To examine a representative case series of drug and related therapeutic adverse events in New Zealand public hospitals with a view to assessing their occurrence, causation, patient impact and preventability. Methods An analysis was carried out on 192 drug and related therapeutic adverse events classified by reviewing physicians. These were identified from among 850 adverse events determined by two-stage retrospective review of a representative sample of 6579 medical records drawn from 13 public hospitals in 1998. Results One fifth of all adverse events were in the combined group, comprising drug (15.4%) and related therapeutic (7.3%) incidents. In comparison with other adverse events these incidents appeared to be more common among older patients, were less likely to have occurred in hospital, and had slightly less impact on patients. Cardiovascular drugs accounted for nearly half of drug events; poor infection management, by contrast, was the dominant factor among related therapeutic events, with problems in cardiovascular management also important. Inadequate monitoring and follow up of medication was identified as the most common reason for failure to prevent both drug and related therapeutic adverse events. Conclusions This study shows that morbidity related to medications is extensive. Drug-related adverse events are frequent and many are preventable. Better monitoring and more appropriate medication choice for individuals are the most common prevention strategies identified.