Serial serum creatinine monitoring may detect early GFR decline above 60 mL/min before CKD stage 3

A descriptive article proposes an approach for detecting early glomerular filtration rate (GFR) decline above 60 mL/min, before chronic kidney disease (CKD) stage 3. The method involves monitoring serial serum creatinine (sCr) levels referenced to an individual's historical maximum, rather than relying on estimated GFR (eGFR) equations. The authors argue that serial creatinine is more reliable than GFR estimating equations at GFRs above 60 mL/min, referencing a prior standard that found low tubular secretion of creatinine at GFRs above 80 mL/min and suggested observing subtle sCr changes. They explain why this method can extend down to 60 mL/min.

Four illustrative patient cases demonstrate how the sCr method, when it suggests increased risk, can trigger investigation to separate benign processes that alter sCr from a true decline in GFR indicative of pre-chronic kidney disease (preCKD). The authors note the approach appears practical for 'race-free' clinical monitoring and early intervention. No specific safety, tolerability, or adverse event data are reported, as this is a methodological description.

Key limitations are not explicitly reported, but the article's nature as a descriptive, explanatory piece presenting a method and case examples is a fundamental constraint. The text does not establish causation and references findings from another source without providing new statistical measures of certainty, such as p-values, confidence intervals, or quantitative effect sizes. The practice relevance is restrained; this is not a clinical trial with measured outcomes, and the results are based on re-examining a reference and case examples rather than a controlled study.