Dr. Steven Rigatti, Consulting Medical Director to CRL, highlights a study of the morbidity and mortality implications of eGFR as determined by creatinine and cystatin C, as well as albuminuria.
At CRL we are always keeping an eye out for research which corroborates (or conflicts with) our own when it comes to the mortality implications of laboratory values. A recent study published in the Journal of the American Medical Association (JAMA) is one example1. In this study, researchers pooled data from over 130 global cohorts, nearly 40 million people, to study the morbidity and mortality implications of eGFR as determined by creatinine and cystatin C, as well as albuminuria.
The authors were able to study the relationship between eGFR, albuminuria and many outcomes including all-cause mortality, cardiovascular mortality, stroke, myocardial infarction, and hospitalization. They ran separate analyses for eGFR determined by creatinine alone and by the combination of creatinine and cystatin C. 
Their findings demonstrated that eGFR and albuminuria act in concert in terms of their mortality risk. Either can be mildly abnormal with only a mild effect on mortality, while more severely abnormal levels in either have very high risks associated with them. Researchers also noted that when eGFR was calculated using cystatin C there was no mortality associated with high eGFR, as is seen when creatinine alone is used.
The overall risk profile for mortality was similarly reproduced for the morbidity outcomes evaluated. This research corroborates what we have seen here at CRL and published in industry journals. This newly published data extends our findings by combining eGFR and albuminuria and also considers outcomes other than mortality.
About the Author
Dr. Steven J. Rigatti is a consulting medical director with Clinical Reference Laboratory, with 12 years’ experience in the life insurance industry. He is the current chair of the Mortality Committee of the American Academy of Life Insurance Medicine.
1 Writing Group for the CKD Prognosis Consortium; Estimated Glomerular Filtration Rate, Albuminuria, and Adverse Outcomes, An Individual-Participant Data Meta-Analysis. JAMA. 2023;330(13):1266-1277. doi:10.1001/jama.2023.17002