Current state of continuous renal replacement therapy for acute kidney injury in Japanese intensive care units in 2011: analysis of a national administrative database.

BACKGROUND

Nationwide data for the prevalence and outcomes of patients receiving continuous renal replacement therapy (CRRT) in intensive care units (ICUs) are scarce. This study assessed the status of CRRT in Japanese ICUs using a nationwide administrative claim database.

METHODS

Data were extracted from the Japanese Diagnosis Procedure Combination database for 2011. From a cohort of critically ill patients aged 12 years or older who were admitted to ICUs for 3 days or longer, acute kidney injury (AKI) patients treated with CRRT were identified. The period prevalence of CRRT and in-hospital mortality were calculated. Logistic regression analysis identified factors associated with in-hospital mortality.

RESULTS

Of 165 815 ICU patients, 6478 (3.9%) received CRRT for AKI. The most frequent admission diagnosis category was diseases of the circulatory system (n = 3074). The overall in-hospital mortality rate of the CRRT-treated AKI patients was 50.6%. Clustering patients into four groups by background revealed the lowest in-hospital mortality rate of 41.5% for the cardiovascular surgery group (n = 1043) compared with 53.5% for the nonsurgical cardiovascular group (n = 2031), 51.7% for the sepsis group (n = 1863) and 51.6% for other cases (n = 1541). Multiple logistic regression analysis showed a significant association of these four group classifications with in-hospital mortality in addition to age, hospital characteristics (type and volume), time from hospital admission to CRRT initiation and interventions performed on the day of CRRT initiation.

CONCLUSIONS

Using a large Japanese nationwide database, this study revealed remarkably high in-hospital mortality of CRRT-treated AKI patients, although the period prevalence of CRRT for AKI in ICUs was low.