An observational study of 6,245 patients with chronic kidney diseases not on dialysis in the Study of Heart and Renal Protection revealed that patients with cystic kidney disease have a higher risk of end-stage renal disease (ESRD) than those with glomerulonephritis and diabetic nephropathy. However, the risk of death before ESRD was higher in patients with diabetic nephropathy than those with cystic kidney disease. Estimated glomerular filtration rate and albuminuria were weakly associated with a risk of ESRD in patients with cystic kidney disease.