Co-abuse of amphetamine and alcohol harms kidney and liver.

The prevalence of alcohol use disorder was found 75% higher among amphetamine dependent patients. Alcohol and amphetamine alone have nephrotoxicity and hepatoxicity. But, the degree of risk with coabuse of alcohol and amphetamine is unknown. The objective of this study was to assess toxic effects of amphetamine-alcohol co-abuse on the liver and kidney. he present study was a cross-sectional study conducted et al. Amal Hospital for Mental Health, Qassim region, KSA and include one hundred participants. Seventy-five participants were patients hospitalized for the treatment of abuse, and twenty-five participants, were healthy voluntaries, have no history of abuse. An experienced psychiatrist conducted patient interviews and assessed the patients using the DSM-5 criteria. The data from healthy participants were considered as a control. The abuse group was paired with the control group by age and lifestyle. Participants were split into: Group I: Control group (n = 25); Group II: Amphetamine (AMP) abuser group (n = 25); Group III: Alcohol abuser group (n = 25) and Group IV: Combined drug abuser group (AMP and alcohol) (n = 25). The socio-demographic data was collected. Complete medical examination, Body Mass Index and samples of blood and urine were collected from all participants for analytical tests; determination of alcohol and AMP levels, kidney functions and liver functions. The mean BMI values in groups II, III, and IV showed no significant change from the control group. The serum level of albumin and alkaline phosphatase showed significant decrease in all abuser groups. While, alanine transaminase (ALT), Aspartate transaminase (AST) and osteopontin levels showed significant increase in all abuser groups. Fasting blood sugar values showed significant increase in alcohol abusers. On the other hand, it revealed no significant change in AMP and combined groups. The mean values of urea showed no significant change in AMP and alcohol abusers and significant increase in combined drug abuser group. The serum creatinine and all abuser groups showed significant increase in Cystatin C. The alteration in the most of studied biochemical parameters were more than two folds in combined group compared with that of AMP or alcohol groups. Study reveals synergistic liver and kidney toxicity. Amphetamine-alcohol co-abuse significantly heightens kidney and liver toxicity.

Renal function and risk of dementia: a Mendelian randomization study.

BACKGROUND: The burgeoning recognition of the nexus between renal functionality and the prevalence of dementia has precipitated a surge in research endeavors. This study aims to substantiate the causal relationship between kidney functionality and dementia. METHODS: We utilized clinical renal function metrics from the Chronic Kidney Disease Genetics (CKDGen) Consortium and diverse dementia types (Alzheimer's disease [AD] and vascular dementia) from the FinnGen Biobank by using Mendelian randomization analysis. At the stratum of genetic susceptibility, we tested the causal relationship between variations index in renal function and the occurrence of dementia. Inverse-variance weighted (IVW) method was the main analysis, and several supplementary analyses and sensitivity analyses were performed to test the causal estimates. RESULTS: The findings indicate a significant correlation between each unit increase in cystatin C-based estimated glomerular filtration rate (eGFR-cys) levels was significantly associated with a reduction in the incidence of late-onset Alzheimer's disease (LOAD) (IVW: OR = 0.35, 95% CI: 0.13-0.91, p = 0.031). After adjusting for creatinine-based eGFR (eGFR-cre) and urinary albumin-to-creatinine ratio (UACR), a causal relationship was still identified between elevated levels of eGFR-cys and decreased risk of LOAD (IVW: OR: 0.08; 95% CI: 0.01-0.97, p = 0.047). Sensitivity tests demonstrated the reliability of causal estimates. CONCLUSIONS: The association between renal function based on cystatin C and the augmented risk of developing AD lends support to the perspective that regular monitoring of cystatin C may be a valuable investigative biomarker.

Associations between leisure time, non-leisure time physical activity, and kidney function in Japanese adults: a cross-sectional study.

BACKGROUND: Chronic kidney disease (CKD) contributes to decreased life expectancy. We examined the association between leisure-time physical activity (LTPA), non-leisure-time physical activity (non-LTPA) and kidney function. METHODS: This was a cross-sectional study including 32 162 community-dwelling adults aged ≥ 20 years from the Tohoku Medical MegaBank community-based cohort study. Kidney function was evaluated using cystatin C-based estimated glomerular filtration rate (eGFR) as well as self-reported LTPA and non-LTPA. CKD was defined as either eGFR decline (≤ 60 mL/min/1.73 m2) or presence of albuminuria (albumin-creatinine ≥ 30 mg/g). The association between domain-specific physical activity and kidney function, and CKD prevalence was examined using multivariable-adjusted ordinary least squares and modified Poisson models. RESULTS: The mean eGFR was 98.1 (± 13.2) mL/min/1.73 m2. 3 185 (9.9%) participants were classified as having CKD. The mean LTPA and non-LTPA levels were 2.9 (± 4.2) and 16.6 (± 14.2) METs-hour/day, respectively. For LTPA, in the adjusted model, the quartile groups with higher levels had a higher kidney function (ß, 0.36; 95% confidence intervals [CI], [0.06, 0.66]; p = 0.019 for the 2nd quartile, ß, 0.82; 95% CI, [0.51, 1.14]; p < 0.001 for the 3rd quartile, and ß, 1.16; 95% CI, [0.83, 1.49]; p < 0.001 for the 4th quartile), whereas there were no apparent associations for prevalence of CKD. For non-LTPA, 4th quartile was associated with decreased eGFR (ß, -0.42; 95% CI, [-0.72, -0.11]; p = 0.007) and higher prevalence of CKD prevalence (Prevalence ratio, 1.12; 95% CI, [1.02, 1.24]; p = 0.022). These associations with kidney function remained consistent in the subgroup analyses divided by demographic and biological variables. CONCLUSIONS: We observed a positive association between higher LTPA levels and better kidney function, but not association with CKD prevalence. In contrast, higher non-LTPA was negatively associated with both kidney function and CKD prevalence. These findings suggest that promoting LTPA is beneficial for kidney function.

Creatinine and Cystatin C: A Measure of Renal Function in Men With Testosterone-Induced Muscle Hypertrophy.

Creatinine (Cr) is often used as a standalone gold standard marker of kidney function. Cystatin C (Cys C) is a less physiologically labile marker of renal function, particularly in certain subgroups. Herein, we analyze trends in cystatin C as compared to creatinine in men on testosterone replacement therapy with varying body mass indices and percent body fat (PBF). This retrospective analysis observes 227 men with testosterone-induced muscle hypertrophy who visited a men's health tertiary care clinic. All participants were characterized as competitive or recreational athletes. In patients with a normal body mass index (BMI), there was no clinically significant correlation between Cr and Cys C. Slight correlation was seen with overweight (R2 = .27) patients (p < .0001) and obese (R2 = .29) patients (p < .0001). Patients with PBF of 0%-10% (n = 22) exhibited minimal (R2 = .23) positive correlation between Cys C and Cr (p = .03). Positive correlation between Cys C and Cr in patients with PBF of 10%-20% was clinically negligible (R2 = .17, n = 87), modest (R2 = .49) in patients with PBF of 20%-30% (n = 42), and evident (R2 = 1.00) in patients >30% (n = 3) (p < .0001, respectively). Cystatin C measurements display less variance compared with creatinine at differing BMI distinctions. At the upper limit of BMI or PBF in our patient population, cystatin C exhibits minimal to moderate variability compared with creatinine.

Evaluating the Prognostic Significance of Cystatin C Level Variations Pre- and Post-Radiofrequency Catheter Ablation in the Recurrence of Persistent Atrial Fibrillation.

OBJECTIVE: To investigate the correlation between persistent atrial fibrillation (AF) recurrence and alterations in cystatin C levels pre- and post-radiofrequency catheter ablation (RFCA). METHODS: This study encompassed 114 patients diagnosed with persistent AF. Their serum cystatin C levels were assessed both prior to and 3 months after undergoing an RFCA procedure. The variance in cystatin C levels before and after RFCA is represented as ΔCystatin C. Subsequently, we compared these values between two groups: patients who did not experience a recurrence of AF (n = 79) and those who did experience a recurrence (n = 35). RESULTS: A significant reduction in cystatin C levels post-RFCA in both groups, with a more pronounced decrease observed in the non-recurrence group. Moreover, the recurrence group exhibited larger left atrial diameter and volume before RFCA compared to the non-recurrence group. Cox regression analysis indicated that smaller reductions in serum cystatin C levels and greater left atrial volumes before RFCA were associated with an increased risk of recurrence, after adjusting for covariates. The receiver operating characteristic curve indicated an elevated probability of clinical recurrence of AF post-RFCA in patients with a cystatin C decline < 0.08 mg/L (AUC 0.64). The Kaplan-Meier survival analysis revealed that patients with a cystatin C decline > 0.08 mg/L exhibited significantly higher rates of remaining free from recurrence following RFCA across a 24-month follow-up period (Log-rank test p = 0.003). CONCLUSIONS: Alterations in ΔCystatin C levels pre and post-RFCA in the initial phase could independently predict the recurrence of AF.

Creatinine-to-cystatin C ratio and frailty in older adults: a longitudinal cohort study.

BACKGROUND: Creatinine-to-cystatin C ratio (CCR) has been associated with multiple adverse outcomes. However, little is known about its relationship with frailty. We aimed to explore the association between CCR and frailty among older adults. METHODS: A total of 2599 participants aged ≥ 60 years (mean age 67.9 ± 6.0 years, 50.4% males) were included from the China Health and Retirement Longitudinal Study (2011-2015). Baseline CCR was calculated as plasma creatinine (mg/dL) / cystatin C (mg/L) × 10 and was grouped by quartiles. Frailty was evaluated by the validated physical frailty phenotype (PFP) scale and was defined as PFP score ≥ 3. The generalized estimating equations model was used to explore the relationship between CCR and frailty. RESULTS: The frailty risk decreased gradually with increasing CCR in the quartiles (P for trend = 0.002), and the fourth CCR quartile was associated with a significantly lower risk of frailty compared with the lowest quartile (odds ratio [OR] 0.37, 95% confidence interval [CI] 0.19-0.70). When modeling as a continuous variable, per 1-unit increase in CCR was related to 17% decreased odds of frailty (OR 0.83, 95% CI 0.74-0.93). The association was consistent in male and female participants (P for interaction = 0.41). Poisson models revealed that frailty score was negatively associated with CCR (ß= -0.11, 95% CI= -0.19 to -0.04), and sex did not significantly moderate the associations (P for interaction = 0.22). The results were not affected by further adjusting for high-sensitivity C-reactive protein. Similar results were observed by analyses with multiple imputation technique and analyses excluding participants with baseline frailty. CONCLUSIONS: Higher CCR was associated with a lower frailty risk. CCR may be a simple marker for predicting frailty in older adults.

Exploring the correlation between periodontal disease and serum biomarkers in haemodialysis patients.

BACKGROUND: Patients undergoing haemodialysis are more susceptible to infectious diseases, including periodontitis. This study aimed to investigate the Correlation between periodontal disease and serum markers in Yemeni haemodialysis patients. METHODS: A cross-sectional study was conducted on a sample of 70 haemodialysis patients. Patient interviews, clinical examinations, and laboratory tests were performed to collect data. Serum levels of albumin, calcium, phosphorus, haemoglobin, ferritin, and creatinine were measured, with separate measurements for cystatin C The association between categorical variables was assessed using the chi-square test and Pearson's correlation coefficient, considering a significance level of p < 0.05. RESULTS: Significant correlations were found between serum biomarkers and periodontal clinical parameters. Phosphorus, creatinine, albumin, ferritin, and creatinine levels correlated significantly with the Plaque Index (p < 0.001, p < 0.001, p = 0.015, p = 0.018, and p = 0.03). While the Ferritin level showed significant correlations with both the Plaque Index and Miller Classes (r = 0.281, p = 0.018 and r = 0.258, p = 0.031), respectively. The Calcium level showed a significant correlation with the Gingival Index (r = 0.266, p = 0.027). Cystatin C level was statistically correlated with mobility (r = 0.258, p = 0.031). Also, the result showed a significant correlation between Creatinine levels and Periodontitis (r = 0.26, p = 0.03). CONCLUSION: This study provides evidence of a strong association between periodontal disease and chronic kidney disease in Yemeni haemodialysis patients. The findings emphasize the significance of maintaining good oral health in the care of haemodialysis patients.

Differences in the effects of contrast agents on kidney injury and inflammatory response between diabetic and non-diabetic patients and their clinical significance.

With the increasing incidence of coronary heart disease (CHD), contrast-associated nephropathy (CAN) caused by contrast agents required in coronary angiography has gradually become a clinical concern that needs to be solved urgently. At present, CAN has become one of the most common causes of hospital-acquired acute kidney injury, which seriously affects the prognosis and health of patients. How to effectively identify high-risk CAN patients and prevent the occurrence of CAN has become a hotspot of clinical research. In this study, we attempted to evaluate the effect of contrast agents on renal injury in diabetes mellitus (DM) and non-DM patients by observing some indexes of early renal injury and inflammatory factors, so as to provide a more comprehensive reference for early identification of CAN in the future. The results showed that compared with non-DM patients, contrast agents caused more obvious renal damage in DM patients and more significantly activated inflammatory responses, increasing the risk of CAN. Cystatin C (CysC), neutrophil gelatinase-associated lipocalin (NGAL), C-reactive protein (CRP), and neutrophil-lymphocyte ratio (NLR) all showed excellent predictive effects for the occurrence of CAN after coronary angiography in both DM and non-DM patients.

Correlation of serum homocysteine and cystatin C levels with prognosis in heart failure with preserved ejection fraction patients.

OBJECTIVE: This study investigated the relationship of serum homocysteine (Hcy) and cystatin C (Cys C) levels with the prognosis of patients with heart failure with preserved ejection fraction (HFpEF). METHODS: A total of 178 patients with HFpEF who were admitted to our hospital between December 2019 and November 2020 were included. Patients were grouped based on their serum Hcy and Cys C levels: high Hcy level, normal Hcy level, high Cys C level, and normal Cys C level. Cardiac function, ventricular remodeling indices, and prognosis were compared among patients in these groups. Additionally, the predictive value of serum Hcy and Cys C levels for adverse cardiovascular events in HFpEF patients was analyzed. RESULTS: Patients' mean age in the high Hcy level, normal Hcy level, high Cys C level, and normal Cys C level groups was 69.21 ± 4.17,67.74 ± 4.28,69.95 ± 4.98, and 67.06 ± 4.13 years old, respectively. The high Hcy level group exhibited a lower proportion of class II cardiac function according to the New York Heart Association (NYHA) classification and a higher proportion of class IV cardiac function than the normal Hcy level group, with statistically significant differences. Similarly, the high Cys C level group had a lower proportion of class II cardiac function and a higher proportion of class IV cardiac function compared with the normal Cys C level group, with statistically significant differences. Left ventricular end-diastolic internal diameter (LVEDD), left ventricular end-systolic internal diameter (LVESD), and left ventricular mass index (LVMI) were significantly higher in both the high Hcy level and high Cys C level groups compared with the normal group, with statistically significant differences. The rates of all-cause mortality and class I endpoint events were significantly higher in the high Hcy level and high Cys C level groups than in the normal group. Multifactorial logistic regression analysis demonstrated that adverse cardiovascular events were significantly associated with cardiac function class, LVEDD, LVESD, LVMI, Hcy, and Cys C in patients with HFpEF. The area under the curve (AUC) values for Hcy and Cys C, determined using receiver operating characteristic (ROC) curve analysis, were 0.778 (optimal critical value, 25.38) and 0.681 (optimal critical value, 1.56), respectively, for predicting adverse cardiovascular events. Both Hcy and Cys C serum levels were positively correlated with LVEDD, LVESD, LVMI, and NYHA classification. CONCLUSION: Serum levels of Hcy and Cys C were closely associated with cardiac function, ventricular remodeling indices, and prognosis in patients with HFpEF. These levels may serve as valuable indices for assessing HFpEF patients' health status and prognosis, providing important insights into their potential role as biomarkers for HFpEF management and prognosis.

Dynamic changes in the real-time glomerular filtration rate and kidney injury markers in different acute kidney injury models.

In this study, we dynamically monitored the glomerular filtration rate and other assessment of renal function and markers of injury in various mice models of acute kidney injury. Male C57BL/6 mice were utilized to establish acute kidney injury models of sepsis, ischemia reperfusion, cisplatin, folic acid, aristolochic acid and antibiotic. In addition to the real time glomerular filtration rate, renal LCN-2 and HAVCR-1 mRNA expression levels, and serum creatinine, urea nitrogen and cystatin c levels were also used to evaluate renal function. In addition, the protein levels of LCN-2 and HAVCR-1 in renal, serum and urine were measured. Our results demonstrated that the changes in biomarkers always lagged the real time glomerular filtration rate during the progression and recovery of renal injury. Cystatin-c can reflect renal injury earlier than other markers, but it remains higher in the recovery stage. Perhaps the glomerular filtration rate does not reflect the greater injury caused by vancomycin plus piperacillin.

Prevalence and associated factors of glomerular hyperfiltration among adult stable sickle cells in Kinshasa, DR Congo.

INTRODUCTION: Glomerular hyperfiltration is highly frequent, theoretically dependent on cardiac output, low systemic vascular resistance and hemolysis markers. In sickle cell disease (SCD), hyperfiltration is an extremely common phenomenon and occurred in young and early adult patients. Despite the fact that the glomerular hyperfiltration is known as the early manifestations of sickle cell nephropathy, its burden among adult sickle cell disease in sub-Saharan is poor studied. This study aimed to determine the prevalence and associated factors of hyperfiltration. METHODS: This was an analytical multicentric cross-sectional study involving stable adult sickle cell patients in Kinshasa, recruited between March and October 2023. Parameters of interest encompasses demographic, clinical, biological, echocardiographic and pulse wave measurement data. Hyperfiltration was defined using the CDK-EPI equation based on cystatin C; eGFR >130 for women and >140 ml/min/1.73m2 for men. We used multivariate logistic regression analysis to search determinants of glomerular hyperfiltration. RESULTS: Two hundred and fourty six (246) patients with SCD were enrolled. The prevalence of hyperfiltration was 20.7%. In multiple logistic regression analysis, hyperfiltration status was independently associated with age (< 25 years) [3.57 (1.78-7.49); p = 0.027)], female sex [4.36 (2.55-5.62); p = 0.031), CRP (< 6 mg/l) [0.77 (0.61-0.97); p = 0.028)], central systolic pressure (< 100 mmHg) and central diastolic pressure (< 60 mmHg) [0.86(0.74-0.98), p = 0.028)], [(0.83 (0.71-0.98); p = 0.032)]. CONCLUSION: One out of five SS adults exhibits hyperfiltration, which is associated with young age and female sex, whereas low CRP and blood pressure were negative risk factors.

The predictive value of the triglyceride glucose index combined with cystatin C for the prognosis of patients with acute coronary syndrome.

Background: Recent studies have shown that the triglyceride glucose index (TyG) and cystatin C (CysC) are closely related to cardiovascular disease, but there is limited research on the prognosis of patients with acute coronary syndrome (ACS) after percutaneous coronary intervention (PCI). The aim of this study was to explore the predictive value of the combination of the TyG index and CysC in predicting major adverse cardiovascular events (MACEs) in ACS patients who underwent PCI. Methods: This retrospective study included 319 ACS patients who underwent PCI. The clinical endpoint was the occurrence of MACEs, including all-cause mortality, heart failure, non-fatal myocardial infarction, target vessel revascularization, and angina requiring hospitalization. Patients were classified into MACEs (65 cases) and non-MACEs (254 cases) groups. Univariate factor and multivariate analysis were used to identify predictors of MACEs. The receiver operating curve (ROC) of the prediction model of MACEs was determined. Additionally, the net reclassification improvement and integrated discrimination improvement indexes were calculated to further assess the additional predictive value of the risk factors for MACEs. Subgroup and interaction analysis between the TyG index combined with CysC and MACEs were conducted in various subgroups. Patients were stratified according to the optimal cutoff point value of the TyG index and the CysC determined by ROC curve analysis. The Kaplan-Meier analysis method was used to construct a survival curve 1 year after PCI. Results: During a median follow-up period of 14 months, 65 (20.38%) patients had experienced at least one primary endpoint event. Multivariate logistic regression analysis indicated that the TyG index and CysC were independently associated with an increased risk of MACEs after PCI (OR, 2.513, 95% CI 1.451-4.351, P= 0.001; and OR, 4.741, 95% CI 1.344-16.731, P=0.016, respectively). The addition of the TyG index and CysC to the baseline risk model had the strongest incremental effect for predicting MACEs in terms of the C-statistic from 0.789 (95% CI 0.723-0.855, P<0.001) to 0.799 (95% CI 0.733-0.865, P<0.001). Furthermore, Kaplan-Meier analysis demonstrated that a TyG index greater than 9.325 and a CysC value greater than 1.065 mg/ml were significantly associated with an increased risk of MACEs (log-rank, all P < 0.01). Conclusion: The TyG index predicts MACEs after PCI in patients with ASC independent of known cardiovascular risk factors. Adjustment of the CysC by the TyG index further improves the predictive ability for MACEs in patients with ACS undergoing PCI. Thus, both of them are expected to become new prognostic indicators for MACEs in patients with ACS after PCI.

Urinary cystatin-C and urinary NGAL associated with sepsis predicts longer hospital stay in premature newborns.

Aim: To evaluate the urinary biomarkers related to sepsis in preterm newborns (NBs) and to investigate the predictive capacity of these biomarkers for a longer hospital stay.Methods: Serum and urine were collected from 27 healthy NBs, 24 NBs with neonatal infection without sepsis and 11 NBs with sepsis for the measurement of sindecan-1, lipocalin associated with urinary neutrophil gelatinase (uNGAL), urinary cystatin-C (uCysC) and urinary kidney injury molecule-1.Results: Levels of uNGAL and urinary cystatin-C were elevated in NBs with sepsis and neonatal infection, and uNGAL was significant predictor of hospital stay longer than 30 days (odds ratio: 1.052; 95% CI: 1.012-1.093; p = 0.01).Conclusion: uNGAL was associated with sepsis in preterm NBs and was useful to predict extended hospital stay.

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Newborn glomerular function and gestational particulate air pollution.

BACKGROUND: Nephron number variability may hold significance in the Developmental Origins of Health and Disease hypothesis. We explore the impact of gestational particulate pollution exposure on cord blood cystatin C, a marker for glomerular function, as an indicator for glomerular health at birth. METHODS: From February 2010 onwards, the ENVIRONAGE cohort includes over 2200 mothers giving birth at the East-Limburg hospital in Genk, Belgium. Mothers without planned caesarean section who are able to fill out a Dutch questionnaire are eligible. Here, we evaluated cord blood cystatin C levels from 1484 mother-child pairs participating in the ENVIRONAGE cohort. We employed multiple linear regression models and distributed lag models to assess the association between cord blood cystatin C and gestational particulate air pollution exposure. FINDINGS: Average ± SD levels of cord blood cystatin C levels amounted to 2.16 ± 0.35 mg/L. Adjusting for covariates, every 0.5 µg/m³ and 5 µg/m³ increment in gestational exposure to black carbon (BC) and fine particulate matter (PM2.5) corresponded to increases of 0.04 mg/L (95% CI 0.01-0.07) and 0.07 mg/L (95% CI 0.03-0.11) in cord blood cystatin C levels (p < 0.01), respectively. Third-trimester exposure showed similar associations, with a 0.04 mg/L (95% CI 0.00-0.08) and 0.06 mg/L (95% CI 0.04-0.09) increase for BC and PM2.5 (p < 0.02). No significant associations were observed when considering only the first and second trimester exposure. INTERPRETATION: Our findings indicate that particulate air pollution during the entire pregnancy, with the strongest effect sizes from week 27 onwards, may affect newborn kidney function, with potential long-term implications for later health. FUNDING: Special Research Fund (Bijzonder Onderzoeksfonds, BOF), Flemish Scientific Research Fund (Fonds Wetenschappelijk Onderzoek, FWO), and Methusalem.

Impact of Serum Creatinine- and Cystatin C-Based Sarcopenia Index on Renal Outcomes in Non-Dialysis-Dependent Chronic Kidney Disease Patients: Results From the KNOW-CKD Study.

OBJECTIVE: To evaluate the impact of the serum creatinine- and cystatin C-based new sarcopenia index (SI) on renal outcomes in non-dialysis-dependent patients with chronic kidney disease (CKD). METHODS: In this observational Korean Cohort Study for Outcome in Patients With CKD (KNOW-CKD), 1957 patients with CKD stage 1 to stage 4 were analyzed from 2011 to 2019. Men and women were separately assigned to quartile groups according to their SI. The primary outcome was a composite renal outcome consisting of 50% reduction in estimated glomerular filtration rate or end-stage kidney disease. With use of Fine and Gray subdistribution hazard models, the association between the SI and the primary outcome was analyzed. RESULTS: During a median follow-up of 6.0 (4.2 to 7.7) years, the primary composite renal outcome occurred in 528 (28.6%) patients within a median of 3.0 (1.8 to 5.0) years. In unadjusted and adjusted models, lower SI groups had a poor primary outcome compared with the highest group (quartile 4). The hazard ratios for quartiles 1, 2, and 3 compared with quartile 4 in the fully adjusted model were 4.47 (95% CI, 3.05 to 6.56; P<.001), 3.08 (95% CI, 2.13 to 4.48; P<.001), and 2.09 (95% CI, 1.45 to 3.01; P<.001), respectively. Restricted cubic spline regression analyses found a relatively inverse linear relationship between the SI and the composite renal outcome. CONCLUSION: The new SI is an independent predictor of renal outcomes. A low SI is associated with poor renal outcome.

Serum Cystatin C levels increase with increasing visceral fat area in patients with type 2 diabetes mellitus.

The present study aimed to explore the association between serum cystatin C (Cys-C) levels and visceral fat area (VFA) in patients with type 2 diabetes mellitus (T2DM). A total of 208 previously diagnosed T2DM patients who visited our hospital from September 2019 to December 2021 were included and divided into three groups based on tertiles of Cys-C levels, namely, Groups C1, C2, and C3. The clinical data of the subjects were collected, biochemical parameters such as Cys-C levels were determined, and bioelectrical impedance analysis was applied to determine the VFA and subcutaneous fat area (SFA). The VFA in Group C1 was lower than that in Groups C2 and C3 (all P < 0.05), with no significant difference in VFA between Groups C2 and C3 (P > 0.05). Spearman's correlation analysis revealed that the serum Cys-C level was positively correlated with age, VFA, SFA, insulin resistance index, waist circumference, body mass index, systolic blood pressure, serum creatinine level, and blood uric acid level (r = 0.543, 0.353, 0.168, 0.148, 0.365, 0.264, 0.25, 0.497, and 0.155, respectively; P < 0.05) and negatively correlated with glycated haemoglobin levels (r = -0.175, P < 0.05). Univariate linear regression analysis revealed that VFA was positively correlated with the Cys-C level (ß = 0.002, 95% CI = 0.001-0.003, P < 0.05), with an increase of 0.002 mg/L in the Cys-C level for each 1 cm2 increase in VFA. Further multivariate linear regression analysis was performed with the serum Cys-C level as the dependent variable and age, VFA, SFA, insulin resistance (HOMA-IR), WC, BMI, SBP, Cr, UA, and HbA1c as the independent variables. The results suggested that VFA was positively correlated with serum Cys-C level (ß = 0.001, 95% CI = 0.000-0.002, P < 0.05), with serum Cys-C levels increasing by 0.001 mg/L for every 1 cm2 increase in VFA. Using a VFA ≥ 100 cm2 as the criterion for visceral obesity, ROC analysis revealed that the Cys-C level was a better predictor of visceral obesity, with an area under the ROC curve (AUC) of 0.701 (95% CI = 0.631-0.771, P < 0.05), an optimal cut-off of 0.905 mg/L, and a sensitivity and specificity of 58.3% and 75.2%, respectively. The results suggested that the serum Cys-C level was correlated with the VFA in patients with T2DM and that Cys-C may play a vital role in T2DM patients with visceral obesity.

Serum creatinine and serum cystatin C as an index of muscle mass in adults.

PURPOSE OF REVIEW: Serum creatinine reflects both muscle mass and kidney function. Serum cystatin C has recently been recommended as an additional marker for estimating kidney function, and use of both markers together may provide an index of muscle mass. This review aims to describe the biological basis for and recent research examining the relationship of these markers to muscle mass in a range of adult populations and settings. RECENT FINDINGS: This review identified 67 studies, 50 of which had direct measures of muscle mass, and almost all found relationships between serum creatinine and cystatin C and muscle mass and related outcomes. Most studies have been performed in older adults, but similar associations were found in general populations as well as in subgroups with cancer, chronic kidney disease (CKD), and other morbid conditions. Creatinine to cystatin C ratio was the measure examined the most often, but other measures showed similar associations across studies. SUMMARY: Measures of serum creatinine and cystatin C together can be an index of muscle mass. They are simple and reliable measures that can be used in clinical practice and research. Further study is needed to determine actionable threshold values for each measure and clinical utility of testing and intervention.

Peripheral dopamine suppression and elevated cystatin C in early diabetic nephropathy in spontaneously diabetic rats.

Intrarenal dopamine plays a protective role against the development of diabetic nephropathy during the early stages of the disease. In streptozotocin-induced diabetic mice with renal-specific catechol-O-methyl transferase knockout, intrarenal dopamine was found to suppress glomerular hyperfiltration, reduce oxidative stress and inflammation, and inhibit fibrosis. However, although dopamine activation in streptozotocin-induced diabetic models has been shown to provide renal protection, the role of dopamine in models of naturally induced diabetes mellitus is still unclear. In the present study, we orally administered 10 mg/kg benserazide, a peripheral decarboxylase inhibitor, to spontaneously diabetic Torii rats daily to investigate the activation of the renal dopaminergic system during the progression of diabetic nephropathy. Our findings show that peripheral dopamine decreased urinary 8-iso-prostaglandin F2α and suppressed increases in plasma cystatin C levels. This study demonstrates that a reduction in peripheral dopamine can exacerbate renal dysfunction, even in the early stages of diabetic nephropathy characterized by glomerular hyperfiltration, thereby clarifying the pivotal role of endogenous peripheral dopamine in modulating oxidative stress and kidney performance.NEW & NOTEWORTHY By administering a peripheral decarboxylase inhibitor, we revealed that peripheral dopamine inhibits both the increase in urinary 8-iso-prostaglandin F2α, an oxidative stress marker, and the increase in plasma cystatin C, an early renal dysfunction marker, even in the early stages of diabetic nephropathy characterized by glomerular hyperfiltration. By visualizing renal dopamine precursor distribution, we highlighted the role of endogenous renal dopamine in oxidative stress and renal function following the onset of glomerular hyperfiltration.

Associations Between CYP3A5 (c.6986A>G) Gene Polymorphism and Kidney Impairment in Hypertensive Adults Without Cystatin C Elevation.

OBJECTIVE: This study aimed to explore the potential role of CYP3A5 (c. 6986A>G) gene polymorphism in predicting kidney function impairment in patients with hypertension who did not have elevated serum cystatin C. METHODS: We recruited a group of patients with hypertension who did not have elevated cystatin C and analyzed the CYP3A5 (c. 6986A>G) gene polymorphism. Chi-square tests were used to compare the clinical characteristics and genotypic distribution between the two groups. Logistic regression analysis was used to explore the association between CYP3A5 (c.6986A>G) gene polymorphism and renal function impairment in hypertension with non-elevated cystatin. RESULTS: In patients with hypertension who participated in the study, there was a significant association between CYP3A5 (c. 6986A>G) gene polymorphism and kidney function impairment (p < 0.05). Patients with the CYP3A5 (c. 6986A>G) mutation display a greater risk of kidney function impairment. CONCLUSION: CYP3A5 (c. 6986A>G) gene AA homozygote polymorphism significantly increases risk of kidney function impairment in patients with hypertension with normal cystatin C. However, further studies are needed to validate this association and to further understand the mechanism of CYP3A5 (c. 6986A>G) gene polymorphism in kidney function impairment in patients with hypertension.

Diagnostic and prognostic value of serum Cys-C, retinol-binding protein, and ischemia-modified albumin in patients with coronary heart disease: A diagnostic accuracy study.

The use of 3 biomarkers - cystatin-C (Cys-C), retinol-binding protein (RBP), and ischemia-modified albumin (IMA) - for the clinical classification and outcome of coronary heart disease (CHD) has not been adequately evaluated. We explored the serum levels of these 3 markers and evaluated their diagnostic and prognostic values in patients with CHD. This retrospective case-control study, conducted between June 2017 and June 2018, included 201 patients with CHD hospitalized at the Henan Provincial People's Hospital and 127 healthy individuals from Henan Provincial People's Hospital as controls. Cys-C, RBP, IMA levels, and other laboratory parameters in the 2 groups were determined, and patient outcomes were analyzed. Cys-C, RBP, and IMA levels were higher in the case group than in the control group (P < .05). Logistic regression analysis confirmed that these 3 biomarkers were independent risk factors for CHD. Each indicator has clinical significance in the diagnosis and prognosis of CHD, with RBP being the most significant. The AUC value for CHD detection using a combination of the 3 indicators was 0.783, and the sensitivity and specificity values were 78% and 74.6%, respectively. Simultaneous detection of Cys-C, RBP, and IMA could be an optimal method for early diagnosis and prognosis of CHD.