Objectives: The objectives were to determine the incidence of drug-related deaths in a university hospital and to find out which drugs are most commonly involved in these cases.
Methods: The files of 1511 death cases (97.7% of all death cases in the Helsinki University Central Hospital during the year 2000) were scrutinised. In the cases of suspected drug-related deaths excluding suicides, the medication, its duration and indications, the route of drug administration, and the type of the adverse reactions were determined. The probability of a fatal adverse drug reaction was classified according to WHO's classification. In addition, the incidence of drug-related deaths was calculated from the death certificates.
Results: Scrutiny of the patients' files showed that 75 of the death cases (5.0% of all deaths) were certainly or probably drug-related. This corresponds to about 0.05% of all hospital admissions. The most common adverse reactions were neutropenia caused by antineoplastic agents and gastrointestinal or intracranial haemorrhage due to anticoagulants or nonsteroidal anti-inflammatory drugs (NSAIDs). The incidence of drug-related deaths is only 0.5% when based on the International Classification of Diseases (ICD) codes in death certificates.
Conclusions: Adverse drug reaction is a significant cause of death. Most of the deaths occurred in seriously ill patients with high-risk medication and they are seldom preventable. Incidence figures based on death certificates only may seriously underestimate the true incidence of fatal adverse reactions.