Assessment of creatinine and cystatin C-based eGFR equations in Chinese older adults with chronic kidney disease

Application of creatinine-based eGFR equations in Chinese septuagenarians and octogenarians

PURPOSE

The utilization of creatinine-based estimated glomerular filtration rate (eGFR) equations in the adult population is acknowledged. Nevertheless, the appropriateness of creatinine-based eGFR in septuagenarians and octogenarians is debatable. This study evaluates the creatinine-based equations in Chinese septuagenarians and octogenarians cohorts.

PATIENTS AND METHODS

This study employed a retrospective design, utilizing a review of the hospital medical records system to identify 347 hospitalized participants within the Division of Geriatrics or the Division of Nephrology. These participants underwent renal dynamic imaging with 99 m Tc-DTPA and serum creatinine testing. Comparison of the equations was performed, including the full age-spectrum equation (FAS-Cr equation), European Kidney Function Consortium equation (EKFC equation), Chronic Kidney Disease Epidemiology Collaboration equation for Asian (Asian CKD-EPI equation), Xiangya equation, and Lund-Malmö revised equation (LMR equation).

RESULTS

Most equations tended to underestimate GFR. The FAS-Cr equation had the smallest interquartile range (IQR), while the Asian CKD-EPI equation (mGFR ≥ 30) and Xiangya equation (mGFR < 30) had the biggest IQRs. The FAS-Cr equation had the highest overall P30 of 63.98%, while the Asian CKD-EPI equation had the highest P30 of 75.64% in mGFR ≥ 60. The Xiangya equation, on the other hand, reported the lowest P30 of 36.36% in mGFR < 30. We discovered similar patterns in root-mean-square error (RMSE) as P30. GFR category misclassification rates in the entire cohort ranged from 46.11 to 49.86% for all equations. The FAS-Cr equation exhibited an advantage in octogenarians over other equations in the GFR category misclassification with mGFR lower than 60 ml/min/1.73 m2.

CONCLUSION

None of the creatinine-based equations in this study could perform well regarding precision, accuracy, and CKD stages' classification for the Chinese elderly. Nevertheless, the FAS-Cr equation should be suitable for octogenarians with mGFR lower than 60 ml/min/1.73 m2.

Cystatin C and eGFRCKD-EPI-CysC: novel biomarkers for renal impairment diagnosis and two-year progression-free survival in multiple myeloma

To evaluate cystatin C (CysC) and estimation of glomerular filtration rate (GFR) calculated using the formula, CKD-EPI-CysC (eGFRCKD-EPI-CysC) for renal impairment diagnosis and predicting the prognosis of patients with multiple myeloma (MM). One hundred-fourteen patients with MM and 38 healthy individuals were recruited for the study. Data on clinical characteristics and renal function-related biochemical indicators were collected and analyzed. Patients with MM had increased levels of CysC (1.25 (0.97-2.31) vs. 0.84 (0.80-0.92), respectively, p < 0.001) and decreased levels of eGFRCKD-EPI-CysC (53.0 (24.4-81.1) vs. 97.2 (87.0-104.5), respectively, p < 0.001), compared with healthy individuals. There were significantly more patients with elevated CysC levels than with elevated sCr levels (64.9% vs. 41.2%, respectively, p < 0.001). The CKD-EPI-CysC formula detected more patients with eGFR < 60 ml/(min × 1.73 m2) than the CKD-EPI-sCr formula (52.63% vs. 37.72%, respectively, p < 0.001). Correlation analysis found that only CysC, eGFRCKD-EPI-CysC, and eGFRCKD-EPI-sCr-CysC strongly correlated with β2-microglobulin in group ISS-I. Logistic regression analysis was used to screen CysC (OR = 1.495, 95% CI = 1.097-2.038, p = 0.011) and eGFRCKD-EPI-CysC (OR = 0.980, 95% CI = 0.967-0.993, p = 0.003) as independent prognostic indicators for 2-year-progression-free survival (PFS) of patients with MM. Receiver operating characteristic curve analysis found that CysC values >1.70 mg/L had 67.6% sensitivity and 65.2% specificity and eGFRCKD-EPI-CysC values <38.62 ml/(min × 1.73 m2) had 65.2% sensitivity and 67.6% specificity for 2-year PFS of patients with MM. In summary, CysC and eGFRCKD-EPI-CysC were more sensitive than sCr and eGFRCKD-EPI-sCr for predicting renal impairment in patients newly diagnosed with MM. Increased CysC and decreased eGFRCKD-EPI-CysC levels were effective predictors of 2-year PFS of patients with MM.

Comparison of glomerular filtration rate estimating equations in older adults: A systematic review and meta-analysis

BACKGROUND

Debates persist regarding the performance of existing glomerular filtration rate (GFR) estimating equations in older individuals. We performed this meta-analysis to assess the accuracy and bias of six commonly used equations, including the Chronic Kidney Disease Epidemiology Collaboration creatinine equation (CKD-EPICr) and its combination with cystatin C (CKD-EPICr-Cys), with the corresponding pair of the Berlin Initiative Study equations (BIS1 and BIS2) and the Full Age Spectrum equations (FASCr and FASCr-Cys).

METHODS

PubMed and the Cochrane Library were searched for studies comparing estimated GFR (eGFR) with measured GFR (mGFR). We analyzed the difference in P30 and bias among the six equations and investigated subgroups based on the area (Asian and non-Asian), mean age (60-74 years and ≥75 years), and levels of mean mGFR (<45 mL/min/1.73m2 and ≥45 mL/min/1.73m2).

RESULTS

27 studies with 18,112 participants were included, all reporting P30 and bias. BIS1 and FASCr exhibited significantly higher P30 than CKD-EPICr. While no significant differences were observed between FASCr and BIS1, or among the three combined equations in terms of either P30 or bias. Subgroup analyses revealed FASCr and FASCr-Cys achieved better results in most situations. However, in the subgroup of mGFR<45 mL/min/1.73m2, CKD-EPICr-Cys had relatively higher P30 and significantly smaller bias.

CONCLUSIONS

Overall, BIS and FAS provided relatively more accurate estimates of GFR than CKD-EPI in older adults. FASCr and FASCr-Cys may be better suited for various conditions, while CKD-EPICr-Cys would be a better option for older individuals with impaired renal function.

Glomerular filtration rate estimated by differing measures and risk of all-cause mortality among Chinese individuals without or with diabetes: A nationwide prospective study

BACKGROUND

Whether estimated glomerular filtration rates (eGFRs) by differing biomarkers are differentially associated with mortality or whether the associations differ by diabetes status remains unclear, especially in Chinese population.

METHODS

We included 6995 participants without diabetes (mean age: 60.4 years) and 1543 with diabetes (mean age: 61.8 years). Each eGFR measure was divided into normal (≥90 mL/min/1.73 m² ), modestly declined (60 to <90 mL/min/1.73 m² ), and chronic kidney disease (CKD) (<60 mL/min/1.73 m² ) groups. Cox proportional hazards models were used to estimate hazard ratio (HR) of all-cause mortality associated with each eGFR.

RESULTS

Over a follow-up of 7 years, 677 and 215 deaths occurred among individuals without or with diabetes, respectively. Among those without diabetes, all measures of modestly declined eGFR were not associated with mortality, whereas CKD defined by eGFR cystatin C (eGFRcys) and eGFR creatinine (eGFRcr)-cys (HRs were 1.71 and 1.55, respectively) but not by eGFRcr were associated with higher risk of mortality. Among diabetes, all measures of modestly declined eGFR (HRs: 1.53, 1.56, and 2.09 for eGFRcr, eGFRcys, and eGFRcr-cys, respectively) and CKD (HRs: 2.57, 2.99, and 3.92 for eGFRcr, eGFRcys, and eGFRcr-cys, respectively) were associated with higher risk of mortality. Regardless of diabetes status, an addition of eGFRcys or eGFRcr-cys to traditional risk factors lead to a larger improvement in the prediction of all-cause mortality risk than adding eGFRcr.

CONCLUSIONS

The association of eGFR with mortality risk appeared to be varied by its measures and by diabetes status among middle-aged and older Chinese, which needs to be considered in clinical practice.

Optimal Glomerular Filtration Rate Equations for Various Age Groups, Disease Conditions and Ethnicities in Asia: A Systematic Review

(1) Background: The performance of estimated glomerular filtration rate (eGFR) equations in the Asian population has been widely questioned. The primary objective of this study was to gather evidence regarding optimal GFR equations in Asia for various age groups, disease conditions, and ethnicities. The secondary objective was to see whether the equations based on the combination of creatinine and cystatin C biomarkers if employed are satisfactory across different age groups and disease conditions in various ethnicities in Asia compared to those based on either of the single biomarkers. (2) Methods: Validation studies that had both creatinine and cystatin C-based equations either alone or in combination, validated in specific disease conditions, and those which compared the performance of these equations with exogenous markers were eligible only. The bias, precision, and 30% accuracy (P30) of each equation were recorded accordingly. (3) Results: Twenty-one studies consisting of 11,371 participants were included and 54 equations were extracted. The bias, precision, and P30 accuracies of the equations ranged from -14.54 to 9.96 mL/min/1.73 m², 1.61 to 59.85 mL/min/1.73 m², and 4.7% to 96.10%. The highest values of P30 accuracies were found for the JSN-CKDI equation (96.10%) in Chinese adult renal transplant recipients, for the BIS-2 equation (94.5%) in Chinese elderly CKD patients, and Filler equation (93.70%) also in Chinese adult renal transplant recipients. (4) Conclusions: Optimal equations were identified accordingly and it was proven that combination biomarker equations are more precise and accurate in most of the age groups and disease conditions. These can be considered equations of choice for the specific age groups, disease conditions, and ethnicities within Asia.

Quality of life and cognitive assessment in healthy older Asian people with early and moderate chronic kidney disease: The NAHSIT 2013–2016 and validation study

Background

Taiwan has the highest prevalence of chronic kidney disease (CKD). Impaired cognition and quality of life are significant phenomena in the late stages of CKD. We sought to obtain an overview and the attributable effect of impaired glomerular filtration on multiple domains in cognition and dimensions of quality of life for community-based healthy older adults in Taiwan.

Methods

The study was derived from the Nutrition and Health Survey in Taiwan (NAHSIT) 2013–2016, a nationwide cross-sectional study conducted to sample healthy, community-based older adults aged ≥65 years in Taiwan. Participants were categorized into four CKD groups: CKD stage 1, stage 2, stages 3a and 3b, and stages 4–5. The Mini-Mental State Examination (MMSE) and the QoL questionnaire derived from the 12-item Short Form Health Survey (SF-12) were measured. Generalized linear mixed models (GLMMs) and principal component regressions were employed for the analysis and validation, respectively.

Results

Participants with moderate CKD (stages 3a and 3b) showed deficits in global MMSE, domain orientation to time, calculation, complex commands, and role-physical and vitality in QoL questionnaires. In GLMMs, impaired eGFR per 30 mL/min/1.73 m² was associated with lower global MMSE scores (β = -0.807, standard error [SE] = 0.235, P = 0.0007), domain orientation to time (β = -0.155, SE = 0.047, P = 0.0011), calculation (β = -0.338, SE = 0.109, P = 0.0020), complex commands (β = -0.156, SE = 0.079, P = 0.0494), and role-physical (β = -2.219, SE = 0.779, P = 0.0046) dimensions of QoL.

Conclusions

Elderly Han Chinese adults with moderately impaired renal filtration could manifest cognitive deficits in orientation to time, calculation, and impaired quality of life in physical role functioning.

Comparison of cystatin C-based and creatinine-based glomerular filtration rate in the prediction of postoperative residual hypertension in aldosterone-producing adenoma patients after adrenalectomy

Renal function is associated with postoperative residual hypertension in aldosterone-producing adenoma(APA) patients. Cystatin C-based glomerular filtration rate (GFR) can more accurately estimate renal function than creatinine-based methods. However, which renal function estimation method can more accurately predict postoperative hypertension in APA patients is still unknown. We recruited 180 APA patients who underwent adrenalectomy. Preoperative creatinine and cystatin C-based GFRs were calculated. Residual hypertension was defined as persistent hypertension > 140/90 mmHg or requiring anti-hypertensive medications 1 year after surgery. Sixty-five(36.1%) of the 180 APA patients had residual hypertension. Multivariate logistic regression and receiver operating characteristic (ROC) curve analysis showed a combination of creatinine and cystatin method CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) creatinine-cystatin GFR was significantly associated with residual postoperative hypertension and had the largest area under the ROC curve, which was statistically larger than that of Cockcroft-Gault creatinine-based GFR. In both net reclassification index and integrated discrimination index models, CKD-EPI creatinine-cystatin GFR significantly improved the discriminatory power of CG-GFR. Among these renal function estimations used in the presented study, creatinine-cystatin combined GFR was a precise method to predict residual postoperative hypertension in APA patients received adrenalectomy. These finding may help identify those patients with higher risk of residual hypertension after operation.