Only Large Changes in Spot Urine Albumin-Creatinine Ratio Likely Indicate Change in CKD Status

Only large changes in spot urine albumin-creatinine ratio (ACR) likely indicate a change in CKD status, according to a 157-patient American Journal of Kidney Diseases study. Day-to-day variability was substantial and increased in absolute terms, but decreased in relative terms, with increasing baseline ACR. For patients with normoalbuminuria, a change greater than 467% was required to indicate a significant change in albuminuria status with 95% certainty; for those with microalbuminuria, a change of 170% was required; for those with macroalbuminuria, a change of 83% was required; and for those with nephrotic-range proteinuria, a change of 48% was required.