Associated Complex of Urine Creatinine, Serum Creatinine, and Chronic Kidney Disease

Abstract

Background: Impaired kidney function can affect levels of urine (UCR) and serum creatinine (SCR). Objective: Data from National Health and Nutrition Examination Survey for the years 1999-2014 were used to study associations between UCR, SCR, and chronic kidney disease (CKD) stages 1-5. Results: Levels of SCR and UCR were positively correlated for CKD Stages 1-3 and negatively correlated for CKD Stages 4 and 5. Males had higher levels of UCR than females but male-female differences were narrower for CKD Stages 1-3 than for CKD Stages 4-5. Males had higher levels of SCR than females but male-female differences were 30% for CKD Stages 1-3 and 20% for CKD Stages 4-5. NHB had higher levels of UCR than NHW but these differences were 27.5 mg/dL for CKD Stages 1-3 and 17.9 mg/dL for CKD Stage 4 and 5. NHB had about 11% higher SCR levels than NHW for CKD Stages 1-3 and about 20% higher levels than NHW for CKD Stages 4-5. For CKD Stages 1-3, levels of UCR decreased with increase in CKD Stage but levels of SCR increased with increase in CKD Stage. Levels of both SCR and UCR were higher for CKD Sage 5 than for CKD Stage 4. Conclusions: CKD stages affect association between SCR and UCR as well as gender and racial/ethnic differences in both UCR and SCR.