Excess length of stay and economic consequences of adverse events in Dutch hospital patients

BACKGROUND To investigate the average and extrapolated excess length of stay and direct costs of adverse events (AEs) and preventable AEs in Dutch hospitals, and to evaluate patient characteristics associated with excess length of stay and costs. METHODS Data of a large retrospective patient record review study on AEs was used. A stratified sample of 20 Dutch hospitals was included. Excess length of stay and costs attributable to AEs and preventable AEs were calculated and extrapolated to a national estimate. The association between patient characteristics and excess length of stay (and costs thereof) attributable to AEs and preventable AEs was investigated through multilevel linear regression analyses. RESULTS A total of 2975 patient records were included in the analysis, of which 325 experienced one or more AEs. Hospital patients experiencing an AE stayed 5.11 (95% CI 3.91-6.30) more days in hospital and cost €2600 (95% CI €1968-€3232) more compared to those without an AE. There was no significant difference in days and costs between preventable and non-preventable AEs. Extrapolated to a national level, AEs cost more than €300 million, which was 1.3% of the national hospital care budget. Patients with hospital-acquired infections had a statistically significant longer length of stay compared to the reference group (patients with AEs on the cardiovascular system). CONCLUSIONS This study showed that AEs lead to substantial excess length of stay and increased costs. Special attention should be paid to patients with AEs due to an hospital-acquired infection.