In the absence of cardiometabolic diseases, is age an independent factor in assessing renal health and filtration? A pilot study

Abstract

Introduction: Serum creatinine (sCr) is conventionally used to characterize the progressive decline in renal filtration (RF). Assessment of RF and renal health (RH) is traditionally believed to be agedependent. However, in the absence of cardiometabolic disease (CMD), this may not be the case. Objectives: The purpose of this study was to determine the magnitude of age as an influencing factor independent of CMD with novel markers of RH/RF in a single health assessment. Patients and Methods: Fifty-four participants (n = 27 men; n = 27 women; age 33.4 ± 12.5 years; BMI 26.5 ± 5.5; SBP 120 ± 10.4; DBP 77.7 ± 6.7; CHOL 174 ± 30) free of CMD were recruited to assess sCr, urine creatinine (uCr), cystatin C (CyC), and urine epidermal growth factor (uEGF) to calculate estimates of RH/F via uEGF/uCr ratio (uEGFR), eGFR - modification of diet in renal disease (MDRD), CKD-EPI, and sCr/CyC eGFR. Results: There were no significant differences between age groups (20s, 30s, 40s, 50s) in biomarkers and estimates of RH/RF, sCr (P=0.91), uEGF (P=0.46), CyC (P=0.13), CyC eGFR (P= 0.10), MDRD (P=0.12), CKD-EPI (P=0.80), and sCr/CyC eGFR (P=0.12). Post-hoc analysis revealed uEGFR was the only significantly different variable between 40s and 50s age groups (P= 0.02). Conclusion: Changes in RH/RF appear to be independent of age in the absence of CMD. Indicating RH/RF could potentially be maintained in adulthood and throughout the older adult years with the continued absence of CMD.