The reimbursement and cost of acute kidney injury: a UK hospital perspective.

Background: Despite the great interest in acute kidney injury (AKI), there have been very few studies that examined the economic impact and costing methodologies of AKI. We aimed to examine the cost and income of AKI in hospitalised patients over a period of 1 year using the NHS costing system related to that year.

Methods: A total of 627 patients discharged between January 2008 and December 2008 with AKI were identified by International Classification of Disease 10 codes (ICD-10). Basic demographic data were collected using the hospital electronic records, and the severity of AKI was classified according to the Acute Kidney Injury Network (AKIN) classification. We calculated the total income and isolated the AKI income related to AKI-specific finished consultant episodes. Then we conducted a patient level costing exercise using relative value units (RVU) to compare the cost of AKI to the actual income.

Results: The total spell income for all patients was GBP 1,954,922.7; the mean total income per patient was GBP 3,752.3 (95% CI 3,594.6-3,903.9). AKIN stage 3 generated significantly higher total spell and AKI income. The estimated overall cost of treating AKI was higher than the AKI income to the Primary Care Trust (GBP 1,984,543.9 vs. 1,755,395).

Conclusion: AKIN stage 3 has a significant economic impact when compared with AKIN stages 1 and 2. The move towards a patient level costing using RVU could be a more efficient way to match cost and income.