Objective: to gain insight into the scale, nature, preventability and causes of adverse events in hospitalised older patients.
Design: a three-stage retrospective, structured, medical record review study of 7,917 records of patients admitted in 21 Dutch hospitals in 2004.
Main outcome measures: incidence, preventability, clinical process category, consequences and causes of adverse events in hospitalised patients of 65 years and older, compared with patients younger than 65.
Results: adverse events and preventable adverse events occur significantly more often in older patients [6.9% (95% CI: 5.9–8.0%) and 2.9% (95% CI: 2.3–3.7%), respectively] than in younger patients [4.8% (95% CI: 4.0–5.7%) and 1.8% (95% CI: 1.3–2.4%), respectively]. In older patients, the adverse events were more often related to medication (20.1 versus 9.6%) (P < 0.01). An exploration of the causes revealed that the inability to apply existing knowledge to a new and complex situation contributes more often to the occurrence of adverse events in older patients than in younger patients (36.4 versus 24.3%) (P < 0.05).
Conclusion: to reduce the number of adverse events in older patients in the future, more particular training of hospital staff in geriatric medicine is required, with a specific focus on medication.