Influence of adverse drug events on morbidity and mortality in intensive care units: the JADE study

Objective. To identify the influence of adverse drug events (ADEs) on morbidity and mortality in intensive care units (ICUs). Design. A prospective cohort study. Setting. ICU setting at three acute care hospitals in Japan. Participants. All patients aged >= 15 years were admitted to all ICUs during a 6-month study period. Intervention. No intervention. Main Outcome Measures. Mortality in the ICUs and the length of the ICU stay.. Results. We included 459 patients with a total of 3231 patient-days. Ninety-nine ADEs occurred in 70 patients (15%), so that the incidence of ADEs was 30.6 per 1000 patient-days and 21.6 ADEs per 100 admissions. Seventy-three patients (16%) died during their ICU stay. Excluding 38 deaths within 3 days after admission, 12 patients (17%) died among the 70 patients who had at least one ADE during their ICU stay and 23 (7%) died among 351 without an ADE (P = 0.003). The median ICU length of stay was 3 days. Excluding 73 patients who died during their ICU stay, the median ICU stay of patients with at least one ADE was 13 days, while it was only 2 days in the remainder (P < 0.0001). ADEs were associated with longer length of ICU stay but not with mortality even after adjusting for patients' severity of illness. Conclusions. ADEs were common in ICUs and significantly associated with longer length of ICU stay but did not influence on mortality.