Prognostic Value of Isolated High Serum Cystatin C Levels Without Glomerular Filtration Rate Reduction

Med Clin (Barc). 2024 Jun 14;162(11):511-515. doi: 10.1016/j.medcli.2023.12.015. Epub 2024 Feb 21.
[Article in English, Spanish]

Abstract

Objectives: Cystatin C is increasingly used as a marker of renal function as a complement to serum creatinine and glomerular filtration rate (GFR). We have assessed its efficacy as a predictor of mortality in a group of patients with increased cystatin C but GFR> 60mL/min.

Design and methods: We included 608 patients, 65.9% male, 34.6% had diabetes mellitus. The mean age was 58.5±14.5 years and a mean GFR of 64.1±33.5mL/min. Patients were divided into 3 groups: CONTROL (normal cystatin C and GFR> 60mL/min, age 53.3±12.8years, GFR 96.6±22.4mL/min,n=193), INCREASED CYSTATIN (cystatin C>1.03mg/l and GFR>60mL/min, age 58.9±13,1years, GFR 72.2±10.4mL/min, n=40) and CKD (chronic kidney disease, increased cystatin C and GFR <60mL/min, age 61.4±14.8years, GFR 36.0±12.7mL/min, n=160). The relationship with overall mortality was analyzed using the Kaplan-Meier method.

Results: Mean cystatin C was 0.75±0.13 versus 1.79±0.54 in CKD group and 1.14±0.14mg/l, p <0.001). In CONTROL group survival was 93.9% at 5y, compared to 78.8% in the ERC group and 82.3% in the INCREASED CYSTATIN group (p <0.001) Five-year survival before renal replacement therapy was also different for the ERC group (73%, p <0.001 Log Rank) but not between the other two groups (CONTROL 99.0%, INCREASED CYSTATIN 94.3% p=0.08).

Conclusions: Increased plasmatic levels of cystatin C in patients with GFR> 60mL/min was a predictor of increased mortality but not of progression to end-stage renal failure. These results confirm the interest of routinely measuring cystatin C.

Keywords: Chronic Kidney Disease; Cistatina C; Cystatin C; Enfermedad renal crónica; Glomerular filtration rate; Mortalidad; Mortality; Prognosis; Pronóstico; Tasa de filtración glomerular.

MeSH terms

  • Adult
  • Aged
  • Biomarkers* / blood
  • Cystatin C* / blood
  • Female
  • Glomerular Filtration Rate*
  • Humans
  • Kaplan-Meier Estimate
  • Male
  • Middle Aged
  • Predictive Value of Tests
  • Prognosis
  • Renal Insufficiency, Chronic* / blood
  • Renal Insufficiency, Chronic* / diagnosis
  • Renal Insufficiency, Chronic* / mortality
  • Renal Insufficiency, Chronic* / physiopathology

Substances

  • Cystatin C
  • Biomarkers