Assessing glomerular filtration rate (GFR) in elderly Chinese patients with chronic kidney disease (CKD): A comparison of various predictive equations
Introduction
The CKD has been identified as a public health problem. CKD is of high prevalence, it is harmful, costly, preventable and treatable. In almost every country, the proportion of people aged over 60 years is growing faster than any other age group (WHO, 2009), as a result of longer life expectancy. The number of elderly CKD cases increase, too (Brenner and Rector, 1999). The Cockcroft–Gault-equation, MDRD-equation, Jelliffe-1973-equation, Mawer-equation, Hull-equation, Jelliffe-1971-equation, SC-reciprocal-equation, Gate-equation and Bjornsson-equation are the most frequently used GFR prediction equations in the world (NKF, 2002). Most of the equations were derived predominantly from young or middle-aged subjects. Application of these GFR prediction equations to elderly CKD patients is limited, particularly in Chinese patients. On the austere challenge of CKD as well as the aging of the population, it is of great importance to analyze the applicability of formulas based on SC levels in elderly Chinese patients with CKD.
Section snippets
Participants
Patients with CKD diagnosed according to the NKF (2002) (>60 years of age) at the Division of Nephrology, Department of Internal Medicine, The Third Affiliated Hospital of Sun Yet-sun University, Guangzhou, China, were enrolled. Patients with acute kidney function-deterioration, clinical edema, skeletal muscle atrophy, pleural effusion or ascites, malnutrition, amputation, heart failure, or ketoacidosis were excluded from the study. Patients who were taking cimetidine or trimethoprim were
Clinical characteristics
Consecutive patients (n = 103) with CKD, including 25 males and 78 females, were enrolled. The average SC level of enrolled patients was 2.54 mg/dl (range 0.36–10.24). The average of sGFR measured by 99mTc-DTPA renal dynamic imaging method was 40.00 ml/min/(1.73 m2) (range 7.17–94.18). Causes of CKD and CKD stage classification are shown in Table 1. Patients were divided into five groups by 99mTc-DTPA renal dynamic imaging method according to the Kidney Disease Outcomes Quality Initiative (KDOQI) (
Discussion
By the end of 2005, elderly population in China aged 60 years and above was close to 144 million, accounting for 11% of the total population in China. Elderly population is growing at an average annual rate of about 3%. According to the generally acknowledged international standard, the age structure of Chinese population has entered the aging stage. The aging of the population increase austere challenges in China (State Council Information Office, 2006). The number of elderly CKD cases
Conclusions
This is the first study in elderly Chinese patients with CKD to evaluate the application of the most common used GFR-estimation-equations. Our data indicated when SC was checked with enzymatic method, the most frequently used GFR-estimation-equations are not sufficient for estimating GFR and radioisotope studies are still useful to evaluate renal function in elderly Chinese CKD patients. Further improved formulas are needed. At present, if conditions are not available, on the basis of both
Conflict of interest statement
None.
Acknowledgements
Thanks to Prof. M.H. Cheng in Department of Nuclear Medicine, The Third Affiliated Hospital of Sun Yet-sun University, Guangzhou, China, for his support. Thanks also to the patients for their good cooperation.
References (28)
Creatinine clearance estimation from serum creatinine values: an analysis of three mathematical models of glomerular function
Am. J. Kidney Dis.
(1985)Estimation of creatinine clearance when urine cannot be collected
Lancet
(1971)- et al.
Improved GFR estimation by combined creatinine and cystatin C measurements
Kidney Int.
(2007) - et al.
Computer-assisted prescribing of kanamycin for patients with renal insufficiency
Lancet
(1972) - et al.
Application of GFR-estimating equations in Chinese patients with chronic kidney disease
Am. J. Kidney Dis.
(2005) - et al.
Geriatric renal function: estimating glomerular filtration in an ambulatory elderly population
Clin. Nephrol.
(1997) - et al.
Nomogram for estimating creatinine clearance
Clin. Pharmacokinet.
(1983) - et al.
Statistical methods for assessing agreement between two methods of clinical measurement
Lancet
(1986) - et al.
The Kidney
(1999) - et al.
Creatinine clearance, Cockcroft–Gault formula and cystatin C: estimators of true glomerular filtration rate in the elderly?
Gerontology
(2002)