May 2008: Volume 34, Number 5
Report Details Factors in Rising CKD Rates
As the lab community steps up efforts to halt skyrocketing rates of chronic kidney disease (CKD), CDC researchers have joined the call for standardizing the criteria for diagnosing the disease in a report that also describes the dramatic rise in CKD-related hospitalizations over 25 years.
From 1980 to 2005, the number of people hospitalized with a diagnosis of kidney disease, including chronic and acute kidney failures, rose about 285%, from 416,000 to 1.6 million, according to analysis of data from the National Hospital Discharge Survey, 1980–2005 (MMWR 2008; 57: 309–312).
CDC published the report just as AACC and three other medical associations in conjunction with the NKDEP launched a campaign that calls on laboratorians to report eGFRs using the MDRD formula to help identify patients at risk of CKD.
The CDC data reveal that elderly patients helped fuel the increase in kidney disease hospital stays. In 2005, approximately 61.4% of patients hospitalized with kidney disease were age 65 and older, compared to 49.9% in 1980. An increase of about 300% occurred among patients ages 65–74, while a rise of about 350% occurred among patients age 75 and older.
Also driving the jump in hospitalizations for CKD was a consistent increase in stays for acute renal failure (ARF). The age-adjusted rate of ARF hospitalization per 10,000 population increased from 1.8 in 1980 to 36.5 in 2005, with a smaller increase—from 7.4 to 13.8 per 10,000 population—for chronic kidney failure (CKF) during the same period. In 1980, 35% of all kidney disease hospital stays were for CKF, 7.3% were for ARF, and 56.0% were for other kidney disease diagnoses. In 2005, those figures rose to 24.3, 60.05, and 9.3%, respectively.
The researchers propose that the rise in ARF hospitalizations may be related to how the condition is diagnosed, defined, or reflected in hospital discharge codes. The increase corresponds with implementation of 2002 National Kidney Foundation guidelines for evaluating and classifying CKD, the report notes. It suggests that changes in criteria for kidney dysfunction may have driven the increase.