Association of intra-individual differences in estimated GFR by creatinine versus cystatin C with incident cardiovascular disease

Abstract

Background and aims

This study investigates the association between intra-individual differences in estimated glomerular filtration rate based on serum creatinine (eGFR_scr) and cystatin C (ΔeGFR_cysc-scr) and incident CVD.

Methods and results

This study used data from the China Health and Retirement Longitudinal Study (CHARLS) from 2015 to 2020. ΔeGFR_cysc-scr were determined by subtracting eGFR_scr from eGFR_cysc. The outcome was the incidence of CVD, including heart diseases, and stroke, obtained through self-reports. Cox proportional hazard regression models were employed to examine the association between ΔeGFR_cysc-scr and CVD risks. Restricted cubic spline with three knots at the 10th, 50th, and 90th centiles was conducted to flexibly model the association. During this period, 1187 incident CVD events were documented. After adjusting for covariates, the risk of CVD was reduced by 13.2 % (Hazard ratio [HR] = 0.868; 95 % confidence interval [95 % CI]: 0.818–0.921) for every 15 mL/min/1.73 m² increase in baseline ΔeGFR_cysc-scr. Specifically, individuals in negative-ΔeGFR_cysc-scr group (<-15 mL/min/1.73 m²) had a 33.6 % increased risk of CVD events (HR = 1.336; 95 % CI: 1.151–1.551), and positive-ΔeGFR_cysc-scr group (≥15 mL/min/1.73 m²) had a 34.5 % decrease risk of CVD events (HR = 0.655; 95 % CI: 0.541–0.794), compared with those in reference group (−15 to 15 mL/min/1.73 m²). These associations remained robust after adjusting for potential confounders or sensitivity analysis.

Conclusions

Our findings suggest that intra-individual differences in eGFR estimates based on creatinine versus cystatin C are associated with CVD risk in the Chinese population. This highlights the potential value of using both markers for more accurate CVD risk stratification in clinical practice.