Difference Between Estimated GFR Based on Cystatin C Versus Creatinine and Incident Atrial Fibrillation: A Cohort Study of the UK Biobank

The association between the cystatin C- and creatinine-based estimated GFR ratio and post-ablation outcomes in patients with atrial fibrillation

BACKGROUND

The difference between the cystatin C-based eGFR (eGFRcys) and the creatinine-based eGFR (eGFRcr) is associated with the risk of developing atrial fibrillation (AF) risk. However, its impact on AF ablation outcomes is unknown.

METHODS

The associations between the baseline eGFR ratio (eGFRcys/eGFRcr) and the risk of experiencing post-ablation endpoints were evaluated on a continuous scale (restricted cubic splines) and by a priori defined centile categories with Cox proportional hazards regression models. The primary endpoints were AF recurrence and adverse events; the secondary endpoint was rehospitalization.

RESULTS

Among 989 participants (49.2% women; mean age 65.7 years), 313 experienced AF recurrence after a median follow-up of 28 months. After full adjustment for confounding factors, a U-shaped association was observed between eGFR ratio and AF recurrence risk (minimum risk at 0.797). Although a U-shaped trend was observed, there was no statistically significant association between the eGFR ratio and adverse events or rehospitalization. Hazard ratios for AF recurrence, compared to the second quartile, were 1.68 (1.20-2.37) for the first quartile, 1.64 (1.15-2.34) for the third quartile, and 1.96 (1.37-2.80) for the fourth quartile. According to the subgroup analysis, the above association was strongly U-shaped for males and linear for females.

CONCLUSION

In the AF population, both low and high eGFR ratios were associated with an increased risk of post-ablation AF recurrence.

Association between the difference in estimated GFR based on cystatin C versus creatinine in coronary artery diseases

BACKGROUND

The difference in estimated glomerular filtration rate (eGFR) derived from creatinine and cystatin C (eGFRdiff) has been noticed recently and the relationship with poor cardiovascular prognosis has been proven. However, primary prevention of the risk of coronary artery disease (CAD) is equally important but there is a lack of studies specifically investigating this implication.

METHODS

This prospective cohort study utilized data from the UK Biobank, including 437,536 participants without CAD at baseline. The primary outcome was defined as CAD. The eGFRdiff was calculated by subtracting creatinine-based eGFR from cystatin C-based eGFR. Participants were then categorized into a negative, intermediate range, and positive group based on thresholds of -15 mL/min/1.73 m2 and 15 mL/min/1.73 m2. Cox proportional risk models were used to evaluate the associations of eGFRdiff with CAD and the relationship among different genetic risks of CAD.

RESULTS

During a median follow-up of 13.8 years, CAD occurred in 36,797 participants. In the fully adjusted model, compared to midrange eGFRdiff, participants with a positive eGFRdiff had a lower risk of CAD (HR 0.717, 95%CI 0.675-0.762), while with a negative eGFRdiff had a higher risk (HR 1.433, 95%CI 1.399-1.468). When eGFRdiff was treated as a continuous variable, a statistically significant trend toward a lower risk of CAD as eGFRdiff increased (HR 0.982, 95% CI 0.981-0.982). Moreover, this relationship is independent of genetic susceptibility.

CONCLUSIONS

eGFRdiff was associated with CAD risk, where a high eGFRdiff corresponded to a decreased likelihood of CAD onset no matter genetic susceptibility.

Complex Etiologies of the Discordance Between Cystatin C- and Creatinine-Based Estimated GFR and Its Adverse Associations: Findings From the CRIC Study

RATIONALE & OBJECTIVE

The difference between GFR estimated by cystatin C and creatinine (eGFRdiff, defined as eGFRCys - eGFRCr) has been repeatedly associated with adverse outcomes, often ascribed to low muscle mass. However, it is unclear to what extent putative determinants of eGFRdiff, such as low muscle mass, explain associations between eGFRdiff and the outcomes of death and heart failure. Determinants of eGFRdiff have not been investigated to assess impacts on eGFRCys, eGFRCr and ultimately eGFRdiff in a dataset with measured GFR.

STUDY DESIGN

Prospective cohort study for outcomes of eGFRdiff and cross-sectional study for determinants of eGFRdiff.

SETTING & PARTICIPANTS

1,290 adult participants in the Chronic Renal Insufficiency Cohort (CRIC) Study with directly measured iothalamate GFR, 24-hour urine creatinine collections, and plasma measurements of larger molecules, such as beta-2-microglobulin.

EXPOSURE(S)

Baseline eGFRdiff (eGFRCys - eGFRCr) for prospective analysis; putative eGFRdiff determinants for cross-sectional analyses.

OUTCOME(S)

Time to all-cause death, heart failure hospitalization for prospective analyses; eGFR for cross-sectional analyses.

ANALYTICAL APPROACH

Cox proportional hazards regression for prospective analysis and linear regression for cross-sectional analyses.

RESULTS

Among adults with CKD, more positive eGFRdiff was associated with decreased risk of death (aHR 0.80, 95% CI 0.74-0.88) and heart failure hospitalization (aHR 0.83, 95% CI 0.73-94). Neither association was substantially changed by adjustment for putative determinants of eGFRdiff. eGFRdiff was weakly correlated with markers of muscle mass, middle molecule clearance, and other putative determinants of eGFRdiff (e.g., obesity, inflammation). Only 36% of the variance in eGFRdiff was explained by these factors.

LIMITATIONS

Imprecision in measurements, such as 24-hour urine collections.

CONCLUSION

The associations of eGFRdiff with adverse outcomes were unchanged by adjustment for markers of putative determinants, such as muscle mass. Examined putative determinants of eGFRdiff accounted for a minority of the variance in eGFRdiff.

Association of the difference between cystatin C- and creatinine-based estimated glomerular filtration rate with cerebral small vessel disease: A large prospective cohort study

BACKGROUND AND OBJECTIVE

It remains unclear whether the difference between the estimated glomerular filtration rate based on cystatin C and creatinine (eGFRdiff) is associated with cerebral small vessel disease (CSVD). We investigated the correlation of eGFRdiff with SCVD and further evaluated the mediating role of blood pressure.

METHODS

This prospective cohort study included 35,590 neurologically healthy participants at baseline (2006 to 2010) from the UK Biobank. eGFRdiff is divided into two indicators: absolute difference (eGFRabdiff) and ratio (eGFRrediff) based on the calculation between cystatin C and creatinine. CSVD was assessed by calculating white matter hyperintensity volume (WMHV) from T2-FLAIR brain MRI scans (conducted between 2014 and 2021), with values normalized to intracranial volume and log-transformed. Multiple linear regression models and mediation analysis was used to evaluate the associations of eGFRdiff with WMHV.

RESULTS

Participants with negative eGFRabdiff had higher WMHV (β = 0.07, 95 % confidence interval [CL] = 0.04 ∼ 0.10), while participants with positive eGFRabdiff had smaller WMHV (β = -0.05, 95 %CL = -0.09 ∼ -0.02), compared to midrange eGFRabdiff group. Meanwhile, participants with eGFRrediff ≤ 0.7 had higher WMHV compared with participants with eGFRrediff > 0.7 (β = 0.08, 95 %CL = 0.01∼ 0.15) .In addition, hypertension mediated the associations between eGFRdiff and WMHV (12.6 % ∼13.2 %).

CONCLUSION

eGFRdiff was independently associated with WMHV. Our findings suggested that monitoring eGFRdiff has potential benefits in identifying the burden of CSVD in the general population in future.

Discordance between cystatin C-based and creatinine-based estimated glomerular filtration rate and health outcomes in adults: a systematic review and meta-analysis

Background

The intra-individual difference in cystatin C-based and creatinine-based estimated glomerular filtration rate (eGFRcys and eGFRcr, respectively), i.e. eGFR discordance, has recently been demonstrated to have prognostic implications. eGFR discordance was associated with mortality, cardiovascular and renal outcomes. We present a systematic review and meta-analysis to summarize the existing literature.

Methods

We searched PubMed, Embase and MEDLINE up to 28 April 2024 for cohort and cross-sectional studies in English reporting the association of eGFR discordance with mortality, cardiovascular and renal outcomes. The quality of studies was evaluated by Risk Of Bias In Non-randomized Studies-of Exposure (ROBINS-E) form. Data from studies were extracted to a pre-defined table and pooled using a random-effects model. Stratified and sensitivity analyses were performed.

Results

A total of 1489 studies were initially identified, of which 18 studies with longitudinal or cross-sectional designs were included, with a sample size between 373 and 363 494 people. In general, the risk of bias was graded as "low" or "some concerns". eGFR was mainly calculated using Chronic Kidney Disease Epidemiology Collaboration equations, while a few studies applied other equations. An eGFR discordance featuring lower eGFRcys, e.g. eGFRcys ≤60% of eGFRcr, or eGFRcys-eGFRcr ≤-15 mL/min/1.73 m2, was consistently associated with higher mortality and elevated risk of cardiovascular and renal outcomes. People with lower eGFRcys have a 58% greater risk of mortality [hazard ratio (HR) = 1.58, 95% confidence interval (CI) 1.42, 1.76] and 32% greater risk of cardiovascular events (HR = 1.32, 95% CI 1.25, 1.39). People with higher eGFRcys have a 39% lower risk of mortality (HR = 0.61, 95% CI 0.52, 0.70) and 29% lower risk of cardiovascular events (HR = 0.71, 95% CI 0.62, 0.81). No meta-analysis for renal outcomes was conducted due to data availability.

Conclusions

The eGFR discordance serves as a meaningful indicator of adverse health outcomes. The lack of a consensus on the cut-off value of eGFR discordance and the mixture use of eGFR equations warrants attention.

Difference between estimated glomerular filtration rate based on cystatin C versus creatinine and cardiovascular-kidney-metabolic health

Background

The difference between the estimated glomerular filtration rate (eGFR) calculated from cystatin C and creatinine (eGFRdiff) serves as a biomarker of kidney function impairment. However, the role of eGFRdiff in cardiovascular-kidney-metabolic (CKM) health and its impact on mortality in CKM syndrome patients has not yet been studied.

Methods

This study included 3,622 participants from the National Health and Nutrition Examination Survey (NHANES) conducted between 1999 and 2004. Weighted ordinal logistic regression was used to explore the link between eGFRdiff and CKM health, while weighted Cox regression was used to examine the relationship between eGFRdiff and mortality in CKM syndrome patients. Restricted cubic splines (RCSs) were used to analyze the dose-response relationship.

Results

The common odds ratio (cOR) per 10 mL/min/1.73m2 increase in eGFRdiff was 0.86 [95% confidence interval (CI), 0.81 to 0.91]. Compared to the midrange eGFRdiff, the cOR values for the negative and positive eGFRdiff were 1.88 [95% CI, 1.23 to 2.88] and 0.69 [95% CI, 0.58 to 0.83], respectively. During a median follow-up of 201 months, 853 participants died from all causes, while 265 died due to cardiovascular causes. The hazard ratios (HRs) per 10 mL/min/1.73m2 increase in eGFRdiff were 0.88 [95% CI, 0.83 to 0.93] for all-cause mortality and 0.90 [95% CI, 0.81 to 1.00] for cardiovascular mortality cases. Compared to the participants with a midrange eGFRdiff, those with negative eGFRdiff had a 48% higher risk of all-cause mortality, while those with positive eGFRdiff had a 30% lower risk. No significant non-linear associations were found in these regression analyses.

Conclusion

Our study found that eGFRdiff is associated with CKM health and stratified mortality risk in CKM syndrome patients.

Comparison of the correlation of creatinine- and cystatin C-Based estimated GFR and their differences with new-onset heart failure in a community-based population with type 2 diabetes

AIMS

This study aimed to investigate the impact of different estimated glomerular filtration rate (eGFR) values like cystatin C-based eGFR (eGFRcys), creatinine-based eGFR (eGFRcr), and their difference (eGFRdiff; eGFRcys -eGFRcr), on the incidence of heart failure (HF) in patients with type 2 diabetes(T2D).

METHODS

Being a prospective cohort study, it included 7,967 patients with T2D who underwent serum creatinine and cystatin C tests as part of the Kailuan Group's 6th annual health examination (2016). Subsequently, eGFRcys, eGFRcr, and eGFRdiff were calculated. Patients were categorized into three groups: negative (<-15 mL/min/1.73 m2), midrange (-15 to 15 mL/min/1.73 m2), and positive (> 15 mL/min/1.73 m2) eGFRdiff groups, respectively. Furthermore, the relationship between the various eGFR measurements and new-onset HF were studied using Cox proportional hazards regression, and the potential improvement in predictive capability was evaluated by adding these eGFR metrics to established HF risk models.

RESULTS

Among 7967 participants with mean age of 60.51 years, there were 20.92% women and 79.08% men. At baseline, eGFRcys and eGFRcr values differed by more than 15 mL/min/1.73m2 in 41.3% of participants. During a median follow-up period of 3.76 years, there were 172 (2.16%) new HF cases and 517 (6.49%) all-cause deaths. The cumulative incidence of HF in the midrange, negative, and positive eGFRdiff groups was 1.74%, 4.10%, and 0.61%, respectively (p < 0.001). In multivariable adjusted models, participants in the negative eGFRdiff group had higher risk of HF compared with the midrange eGFRdiff group (HR, 2.15; 95% CI, 1.57-2.94). Conversely, participants in the positive eGFRdiff group had lower risk for HF (HR, 0.40; 95% CI, 0.17-0.93). And each 15 mL/min/ 1.73 m2 higher eGFRdiff was associated with 34% (HR, 0.66; 95% CI, 0.58 - 0.47)lower risk of incident HF. The predictive capacity for HF risk in diabetic individuals was enhanced by adding eGFRcys or eGFRdiff to established HF risk models, with eGFRcys showing more significant additional predictive value.

CONCLUSION

These findings suggest that large differences between eGFRcys and eGFRcr were common in community-based population with T2D. Different eGFR metrics can independently predict HF incidence in patients with T2D. Additionally, metrics like eGFRcys and eGFRdiff provide significant predictive value for HF risks beyond traditional risk factors, with eGFRcys showing more pronounced benefits in such cases.