Association of nurse staffing grade and 30-day mortality in intensive care units among cardiovascular disease patients

After the implementation of a policy differentiating inpatient nursing fees, no study is found in the nursing literature for intensive care unit (ICU) patients admitted with cardiovascular (CV) disease exclusively in Korea. This study investigates the relationship between ICU nurse staffing and 30-day mortality using large representative claim database. National Health Insurance Service-Senior (NHIS-Senior) claim database from 2002 to 2013, which was released by the Korean National Health Insurance Service (KNHIS), was used in this study. We included CV disease inpatients as a primary diagnostic code (I20-I25) who had their ICU utilization records from differentiating inpatient nursing fees code, resulting in 17,081 subjects After adjusting for confounders, the hazard ratio (HR) for 30-day mortality after discharge (HR: 1.177; P: .018) and in-hospital 30-day mortality (HR: 1.145; P: .058) were higher in general hospital (GH) than in tertiary hospital (TH). In GH setting, HR for 30-day mortality after discharge (HR: 1.499; P: .010) and in-hospital 30-day mortality (HR: 1.377; P: .042) were higher in grade 7 to 9 than grade 1 to 2, but not in TH setting. This study shows that ICU nurse staffing related to improved mortality risk in GHs. Therefore, adequate nurse staffing to provide safe and high-quality care can be ensured by continuous monitoring and evaluation of nurse staffing.