Trends in dialysis modality for individuals with acute kidney injury

There are no national level data on types of dialysis in use for acute kidney injury (AKI). We aimed to assess trends in dialysis modality for AKI and mortality associated with each modality from 1998 to 2005.

Using data from the 5% Medicare cohort, we identified individuals with AKI requiring dialysis. Individuals with preexisting end-stage renal disease were excluded. Intermittent hemodialysis (IHD), daily intermittent hemodialysis, and continuous renal replacement therapy (CRRT) were defined using Current Procedure Terminology codes. Mortality was defined as death during 30 days after the first dialysis session.

Between 1998 and 2005, there were a total of 18,249 patients identified with AKI requiring renal replacement therapy. CRRT was increasingly used for AKI, with 9.9% of patients in 1998 to 18.3% by 2005. Proportion of daily dialysis decreased during this period, while use of IHD remained stable at approximately 68%. Overall 30-day mortality declined from 44.4% in 1998 to 40.2% in 2005. Crude mortality for CRRT was highest in all years (51.0-61.8%), followed by daily (38.2-49.9%) and IHD groups (35.8-43.4%). Multinomial logistic regression analysis showed that white race, presence of sepsis, atherosclerotic heart diseases, peripheral vascular diseases, dysrhythmia, gastrointestinal and liver diseases, and any year after 2000 were independently associated with higher odds of using CRRT after adjusting for other variables.

The proportion of patients using CRRT has increased over time. Mortality associated with IHD has decreased from 1998 to 2005. Mortality associated with different dialysis modalities is likely the result of severity of illness.