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Abstract: FR-PO1124

Non-GFR Factors Influencing Serum Cystatin C Levels: A Systematic Review

Session Information

Category: CKD (Non-Dialysis)

  • 2301 CKD (Non-Dialysis): Epidemiology, Risk Factors, and Prevention

Authors

  • Adingwupu, Ogechi M., Tufts Medical Center, Boston, Massachusetts, United States
  • Barbosa, Ernesto Rodolpho, Tufts University School of Medicine, Boston, Massachusetts, United States
  • Prabhune, Kshitij, Tufts Medical Center, Boston, Massachusetts, United States
  • Ramesh, Sharanya, Tufts Medical Center, Boston, Massachusetts, United States
  • Levey, Andrew S., Tufts Medical Center, Boston, Massachusetts, United States
  • Inker, Lesley Ann, Tufts Medical Center, Boston, Massachusetts, United States

Group or Team Name

  • Chronic Kidney Disease Epidemiology Collaboration.
Background

Glomerular filtration rate estimation using cystatin C (eGFRcys) is recommended in populations where creatinine-based GFR estimates are inaccurate. Serum cystatin C levels are influenced by factors other than GFR, which could lead to errors in eGFRcys. Optimal use of eGFRcys requires an understanding of the factors that influence serum cystatin C.

Methods

Using a systematic review, we identified studies that evaluated determinants of serum cystatin C levels (SCys) other than GFR. We categorized studies by analysis method: those that adjusted for mGFR in assessing the association between SCys and its determinants, and those that did not adjust for mGFR. For studies where associations were observed, we evaluated the direction and significance of the relationship. Adjustment for mGFR is the optimal method for assessing determinants of SCys, as it accounts for a key confounder. Therefore, we focus on those studies in our results.

Results

16 of the 44 identified studies accounted for measured GFR. Most studies evaluated only one or two factors. Female sex was negatively associated with SCys, and associations with age were inconsistent. Height, weight, body mass index, muscle mass, fat mass, smoking, inflammation, and exogenous steroid use were found to be positively associated with SCys (Figure). Studies that showed no associations were smaller on average.

Conclusion

Our results suggest that SCys concentration may be lower in females, and higher in populations with increased body size, smokers, inflammatory states and individuals on steroids. Inconsistency in results for age may be attributable to study differences.

Non-GFR determinants evaluated in studies that accounted for mGFR and their association with serum cystatin C

Funding

  • NIDDK Support

Digital Object Identifier (DOI)