There is a 3-year decrease in the overall mean kidney function among CRISP participants (-1.1 ml/min per 1.73 m2)
No difference in kidney function among indivuduals with PKD1 or PKD2 gene mutation (-1.11 ml/min per 1.73 m2 and -0.89 ml/min per 1.73 m2 respectively).
Chart Explanation: The mean kidney function decreased by -1.1 ml/min per 1.73 m2 among CRISP participants over 3 years. The most common gene mutations (PKD1 or PKD2) were found in almost 90% of the individuals with ADPKD. However, kidney function did not differ significantly between individuals with PKD1 (-1.11 ml/min per 1.73 m2) or PKD2 (-0.89 ml/min per 1.73 m2)
The Consortium for Radiologic Imaging Studies of Polycystic Kidney Disease (CRISP) is a 10-year prospective cohort study that started in March 1999 and was created to develop innovative imaging techniques and analyses using magnetic resonance (MR) imaging to reliably and accurately measure cyst and renal volume in ADPKD individuals early in the course of their disease. The purpose of this study was to determine if (1) renal or cyst volume can be measured reliably and accurately; (2) change in renal or cyst volume can be detected over a relatively short period of time; and (3) an increase in cyst or renal volume is associated with loss of renal function in ADPKD. The primary overall goal of CRISP was to develop imaging methods to follow disease progression and to evaluate treatments for ADPKD.
Autosomal dominant polycystic kidney disease (ADPKD) is the most commonly inherited genetic renal disease and cause of kidney failure in adults and children. It is characterized by the growth of numerous cysts in the kidneys and often culminates in end-stage renal disease. CRISP was created to develop methods that reliably measure the progression of cyst and renal growth before loss of kidney function among individuals with ADPKD. A total of 241 ADPKD patients between 15 and 46 years old and with a creatinine clearance of >70 ml/min were recruited for CRISP I. Enrolled subjects were evaluated at baseline (magnetic resonance imaging, clinical evaluation) and for 3 years thereafter. Two years after the completion of CRISP I, participants were contacted again to schedule for a baseline evaluation for CRISP II (year 6). 203 participants were enrolled for CRISP II. Complete methods can be found in Harris et al. (2006) and Torres et al. (2011)
|Description of Measure||Annual change in measured kidney function in patients with ADPKD|
|Data Source||Consortium for Radiologic Imaging Studies of Polycystic Kidney Disease (CRISP) study|
|Type of Data Source||Private|
|Data Set||CRISP summarized data|
|Health Care System Data||No|
|Regional or National?||National|
|Demographic Group||ADPKD patients in the CRISP study with relatively intact initial renal function|
|Numerator||Participants with ADPKD enrolled with total kidney function measurement data|
|Denominator||Enrolled CRISP participants with ADPKD with meagnetic resonance imaging and clinical evaluation data|
|Definition of CKD||Cockcroft-Gault estimate of creatine clearence >70mL/min |
|Primary Data Source Indicator||iothalamate glomerular filtration rate (iGFR) (kidney function measurement)|
|Primary Indicator Method of Measurement||Nonradiolabeled iothalamate clearence technique|
|Frequency of Measurement (Primary)||Over several years|
|Secondary (1) Data Source Indicator||Gene type|
|Secondary (1) Indicator Frequency of Measurement||Once; baseline visit|
|U.S. Region Covered by Primary Variable||Mayo Foundation (Rochester, MN), University of Alabama (Brimingham, AL), Emory University (Atlanta, GA), University of Kansas Medical Center (Kansas City, KS)|
|Period Currently Available||2001–2007|
|Additional Data Items of Interest||None|
|Limitations of Indicator||selection bias, confounding.|
|Analytical Considerations||Data summarized by CRISP investigators (see Harris et al. (2006) and Torres et al. (2011) as with all cohort studies, selection bias and possible confounding|
References and Sources:
Torres VE, Grantham JJ, Chapman AB, et al. Potentially modifiable factors affecting the progression of autosomal dominant polycystic kidney disease. Clin J Am Soc Nephrol. 2011;6(3):640-7.
Harris PC, Bae KT, Rossetti S, et al. Cyst number but not the rate of cystic growth is associated with the mutated gene in autosomal dominant polycystic kidney disease. J Am Soc Nephrol. 2006;17(11):3013-9.