Understanding of the role of serum creatinine in a subset of the Brazilian population / Conhecimento de uma amostragem da população brasileira sobre a função da creatinina sérica

Abstract Introduction: Chronic kidney disease is usually asymptomatic, and its diagnosis depends on laboratory tests, with emphasis on serum creatinine and proteinuria. Objective: To assess knowledge on the role of serum creatinine as a biomarker of kidney function in a sample of the Brazilian population. Method: Cross-sectional observational study conducted in São Paulo (SP, Brazil), in which a random adult population was interviewed. Results: A total of 1138 subjects were interviewed, with a median age of 36 years old (27-52); 55.1% were female. Regarding the "creatinine" biomarker, 40.6% stated they had never performed such a test. When asked about their knowledge on the usefulness of this exam, only 19.6% knew its function. The other responses were "I don't know" (71.6%), evaluating heart function (0.9%) and liver function (7.8%). Of those who reported they had already taken a creatinine test, only 29.4% correctly identified the role of creatinine. When dividing the groups into "knows" and "does not know" the function of creatinine, a statistically significant difference (p < 0.05) was observed regarding level of education, female sex, being a healthcare student/worker, having ever measured creatinine, knowing someone with kidney disease and older age. In the multivariate analysis, the main variable related to knowing the creatinine role was having previously taken the test (OR 5.16; 95% CI 3.16-8.43, p < 0.001). Conclusion: There is a significant lack of knowledge about creatinine and its use in checkups. The results indicate that greater efforts are needed from healthcare professionals to raise awareness on the role of serum creatinine.

Resumo Introdução: A doença renal crônica costuma ser assintomática e seu diagnóstico depende da realização de exames laboratoriais, com destaque para a creatinina sérica e pesquisa de proteinúria. Objetivo: Avaliar em uma amostra da população brasileira o conhecimento sobre o papel da creatinina sérica como marcador de função renal. Método: Estudo observacional transversal realizado na cidade de São Paulo (SP, Brasil), em que foi entrevistada uma população adulta aleatória. Resultados: Foram entrevistados 1138 indivíduos, com idade mediana de 36 anos (27-52); 55,1% do sexo feminino. Com relação ao marcador "creatinina", 40,6% afirmaram que nunca realizaram tal dosagem. Quando questionados quanto ao conhecimento sobre a utilidade desse exame, somente 19,6% sabiam a sua função. As outras respostas foram "não sei" (71,6%), avaliar o funcionamento do coração (0,9%) e fígado (7,8%). Dos que afirmaram já terem realizado o exame de creatinina, somente 29,4% acertaram a função da creatinina. Ao dividir os grupos em "sabe" e "não sabe" a função da creatinina, percebeu-se diferença estatisticamente significante (p < 0,05) em relação ao grau de escolaridade, sexo feminino, ser aluno/trabalhador da saúde, ter dosado creatinina alguma vez, conhecer alguém com doença renal e maior idade. Na análise multivariada, a principal variável relacionada com conhecer a função da creatinina foi ter realizado o exame anteriormente (OR 5,16; IC 95% 3,16-8,43, p < 0,001). Conclusão: Há grande desconhecimento sobre a creatinina e seu uso em check-ups. Os resultados indicam que é necessário maior esforço por parte dos profissionais de saúde para divulgar o papel da creatinina sérica.

Serum Creatinine-Cystatin C Based Screening of Sarcopenia in Community Dwelling Older Adults: A Cross-Sectional Analysis.

OBJECTIVES: To compare the discriminative capabilities for the manifestation of sarcopenia or physical frailty between serum creatinine- and cystatin C-derived indices among community-dwelling older adults. DESIGN: Cross-sectional study. SETTING: Primary Care and Community. PARTICIPANTS: We utilized a subset of data from the Frail Elderly in the Sasayama-Tamba Area (FESTA) study, which was initiated in 2015 to gather comprehensive information on various health-related parameters among community-dwelling older individuals (age ≥65 years). MEASUREMENTS: Five serum creatinine-cystatin C based indices including the Sarcopenia Index, the serum creatinine/cystatin C ratio, the disparity between serum cystatin-C-based and creatinine-based estimated GFR, the total body muscle mass index (TBMM), and the prediction equation for skeletal muscle mass index (pSMI) were employed. Sarcopenia and physical frailty were identified based on the Asian Working Group for Sarcopenia criteria and the revised Japanese version of the Cardiovascular Health Study criteria, respectively. The receiver operating characteristic (ROC) and logistic regression analyses were performed to assess the discriminative abilities of these tools. RESULTS: In the analysis of 954 participants, 52 (5.5%) were identified with sarcopenia and 35 (3.7%) with physical frailty. Regarding sarcopenia discrimination, TBMM and pSMI both exhibited area under the curve (AUC) values exceeding 0.8 for both men and women. Concerning the identification of physical frailty, AUC values ranged from 0.61 to 0.77 for males and 0.50 to 0.69 for females. In the multivariate logistic regression analyses, only TBMM and pSMI consistently displayed associations with sarcopenia, irrespective of sex (P<0.001, respectively). On the other hand, no consistent associations were observed between the indices and physical frailty. CONCLUSIONS: This study provides a robust association of a serum creatinine- and cystatin C-derived indices, especially TBMM and pSMI, with sarcopenia among community-dwelling older adults. Conversely, the application of these indices for the screening of physical frailty has its constraints, necessitating further investigation.

Usefulness of the serum creatinine/cystatin C ratio as a blood biomarker for sarcopenia components among age groups in community-dwelling older people: The SONIC study.

AIM: The serum creatinine/cystatin C ratio (CCR) or sarcopenia index is considered a useful marker of muscle mass. However, its usefulness in late-stage older adults remains unclear. We aimed to determine the usefulness of CCR as an indicator of sarcopenia in community-dwelling Japanese adults aged >75 years. METHODS: Our study recruited participants aged 70, 80, and 90 ± 1 years during the baseline years, and included a 3-year follow-up in the Septuagenarians, Octogenarians, Nonagenarians, Investigation with Centenarians study. From 2015 to 2018, 955 participants were eligible: 367 in their 70s, 304 in their 80s, and 284 in their 90s. The diagnostic components of sarcopenia, including "low muscle mass, plus low muscle strength, and/or low physical performance," were evaluated using the bioelectrical impedance analysis-measured skeletal muscle mass index (SMI), handgrip strength, and short physical performance battery (SPPB) score, respectively, in accordance with the Asia Working Group for Sarcopenia 2019 criteria. Separate analyses were performed between each component and CCR, adjusting for sex, body mass index, and other blood biomarkers in each group. RESULTS: The relationship between CCR and sarcopenia components was significant for handgrip strength (ß = 0.21, 0.13, 0.19, and P < 0.0001, =0.0088, <0.0001, for the 70s, 80s, and 90s age groups, respectively); however, it was limited for SMI (ß = 0.14; P = 0.0022, only for the 90s) and not significant for the SPPB score. CONCLUSION: CCR is a limited indicator of sarcopenia in late-stage older adults. Although its association with muscle strength was significant, its relationship with muscle mass and physical performance was less pronounced. Geriatr Gerontol Int 2024; ••: ••-••.

Renoprotective effect of thymoquinone against rhabdomyolysis-induced acute kidney injury in the rat model.

Objectives: Rhabdomyolysis leads to the release of myoglobin, sarcoplasmic proteins, and electrolytes into the blood circulation causing acute kidney injury (AKI). Thymoquinone, a natural compound found in Nigella sativa seeds, has antioxidant and anti-inflammatory effects. This investigation assessed the renoprotective effect of thymoquinone on rhabdomyolysis-induced AKI in rats. Materials and Methods: Male Wistar rats were categorized into six groups (n = 6): 1. Control: (normal saline), 2. Glycerol (50 ml/kg, single dose, IM), 3-5: Glycerol + thymoquinone (1, 2.5 and 5 mg/kg, 4 days, IP), 6. Thymoquinone (5 mg/kg). On day 5, serum and kidney tissue were isolated and the amounts of serum creatinine and blood urea nitrogen (BUN), renal malondialdehyde (MDA), glutathione (GSH.), tumor necrosis factor-alpha (TNF-α), neutrophil gelatinase-associated lipocalin (NGAL), and pathological changes were evaluated. Results: Glycerol increased creatinine, BUN, MDA, TNF-α, and NGAL levels. It decreased GSH amounts and caused renal tubular necrosis, glomerular atrophy, and myoglobin cast in kidney tissue. Co-administration of glycerol and thymoquinone reduced creatinine, BUN, histopathological alterations, and MDA levels, and enhanced GSH amounts. Administration of glycerol and thymoquinone (5 mg/kg) had no significant effect on TNF-α amount but decreased NGAL protein levels. The administration of thymoquinone (5 mg/kg) alone did not display a significant difference from the control group. Conclusion: Rhabdomyolysis from glycerol injection in rats can cause kidney damage. Thymoquinone may attenuate renal dysfunction and oxidative stress. However, the TNF-α level was not significantly affected. Further studies are needed to explore the potential therapeutic effects of thymoquinone in managing AKI.

How a positive fluid balance develops in acute kidney injury: A binational, observational study.

PURPOSE: A positive fluid balance (FB) is associated with harm in intensive care unit (ICU) patients with acute kidney injury (AKI). We aimed to understand how a positive balance develops in such patients. METHODS: Multinational, retrospective cohort study of critically ill patients with AKI not requiring renal replacement therapy. RESULTS: AKI occurred at a median of two days after admission in 7894 (17.3%) patients. Cumulative FB became progressively positive, peaking on day three despite only 848 (10.7%) patients receiving fluid resuscitation in the ICU. In those three days, persistent crystalloid use (median:60.0 mL/h; IQR 28.9-89.2), nutritional intake (median:18.2 mL/h; IQR 0.0-45.9) and limited urine output (UO) (median:70.8 mL/h; IQR 49.0-96.7) contributed to a positive FB. Although UO increased each day, it failed to match input, with only 797 (10.1%) patients receiving diuretics in ICU. After adjustment, a positive FB four days after AKI diagnosis was associated with an increased risk of hospital mortality (OR 1.12;95% confidence intervals 1.05-1.19;p-value <0.001). CONCLUSION: Among ICU patients with AKI, cumulative FB increased after diagnosis and was associated with an increased risk of mortality. Continued crystalloid administration, increased nutritional intake, limited UO, and minimal use of diuretics all contributed to positive FB. KEY POINTS: Question How does a positive fluid balance develop in critically ill patients with acute kidney injury? Findings Cumulative FB increased after AKI diagnosis and was secondary to persistent crystalloid fluid administration, increasing nutritional fluid intake, and insufficient urine output. Despite the absence of resuscitation fluid and an increasing cumulative FB, there was persistently low diuretics use, ongoing crystalloid use, and a progressive escalation of nutritional fluid therapy. Meaning Current management results in fluid accumulation after diagnosis of AKI, as a result of ongoing crystalloid administration, increasing nutritional fluid, limited urine output and minimal diuretic use.

Using nephropathy as an outcome to determine the HbA1c diagnostic threshold for type 2 diabetes.

OBJECTIVE: The hemoglobin A1c (HbA1c) diagnostic threshold for type 2 diabetes (T2D) of 6.5 % (48 mmol/mol) was based on the prevalence of retinopathy found in populations not known to have T2D. It is unclear if nephropathy has a similar HbA1c threshold, partly because it is a rarer complication of early diabetes. This cohort study investigated a very high diabetes prevalence population to determine if a better diagnostic HbA1c value can be established for predicting nephropathy rather than retinopathy in subjects without T2D. METHODS: The urine albumin:creatinine ratios (UACRs) of 2920 healthy individuals from the Qatar Biobank who had an HbA1c ≥ 5.6 %. were studied. Nephropathy was defined as a UACR≥30 mg/g and its prediction by HbA1c was assessed using cut-points ranging from 5.7 to 7.0 % to dichotomize high from low HbA1c. RESULTS: Although there was a significant trend for an increased prevalence of abnormal UACR as the HbA1c threshold increased (p < 0.01), significance was due mostly to subjects with HbA1c ≥ 7.0 % (53 mmol/mol). The odds ratios for abnormal UACR were similar over the 5.7-6.9 % HbA1c threshold range, with a narrow odds ratio range of 1.2-1.6. Utilizing area-under-receiver-operating characteristic curves, no HbA1c threshold <7.0 % was identified as the best predictor of nephropathy. CONCLUSION: Even in a population with a high prevalence of known and unknown diabetes, no HbA1c threshold <7.0 % could be found predicting an increased prevalence of nephropathy. This means there is not a requirement to change the existing retinopathy-based HbA1c threshold of 6.5 % to also accommodate diabetes nephropathy risk.

Abbreviated Urine Collection Compared With 24-Hour Urine Collection for Measuring Creatinine Clearance in Adult Critically Ill Patients: A Systematic Review.

OBJECTIVE: To evaluate the accuracy of abbreviated urine collection (≤12 hours) compared with 24-hour urine collection for measuring creatinine clearance (CrCl) in critically ill adult patients. DATA SOURCES: We searched PubMed, Embase, Web of Science, Google Scholar, and ProQuest Dissertations and Thesis Global; screened reference lists of included studies; and contacted the authors when needed. English studies only were considered with no restriction on dates. STUDY SELECTION AND DATA EXTRACTION: After duplicate removal, 2 reviewers screened titles/abstracts, reviewed full-text articles, and extracted data independently. Studies that compared abbreviated versus 24-hour urine collection for measuring CrCl were included. We assessed the risk of bias using the QUADAS-2 tool. We extracted correlation coefficients, mean prediction errors (ME)-as a measure of bias, and root mean squared prediction errors (RMSE)-as a measure of precision. DATA SYNTHESIS: Five studies were included, comprising 528 adult critically ill adults from surgical, medical, and trauma intensive care units (ICUs). Three studies had high risk of bias, and 2 had low risk. The studies evaluated different durations of urine collection, including 30-minute, 2-hour, 4-hour, 6-hour, and 12-hour. Mean 24-hour CrCl ranged from 57 mL/min/1.73 m2 to 103 mL/min. Abbreviated urine collection led to CrCl that correlated well with the 24-hour measured CrCl (correlation coefficient ranged from 0.8 to 0.95). Mean prediction error ranged from 5 mL/min/1.73 m2 to 16 mL/min (from 8% to 25% of the 24-hour CrCl). Root mean squared prediction error calculated from 1 study was 30.5 mL/min/1.73 m2. RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE: Abbreviated urine collection is used to measure CrCl for renal drug dosing in critically ill patients, but its accuracy is not well-established. CONCLUSIONS: Abbreviated urine collection may overestimate CrCl compared with 24-hour urine collection. Larger, well-conducted studies are needed to evaluate the accuracy of CrCl measured using different durations of urine collection in critically ill patients.

Cystatin C- and Creatinine-based Estimated GFR Differences: Prevalence and Predictors in the UK Biobank.

Rationale & Objective: Large differences between estimated glomerular filtration rate (eGFR) based on cystatin C (eGFRcys) and creatinine (eGFRcr) occur commonly. A comprehensive evaluation of factors that contribute to these differences is needed to guide the interpretation of discrepant eGFR values. Study Design: Cohort study. Setting & Participants: 468,969 participants in the UK Biobank. Exposures: Candidate sociodemographic, lifestyle factors, comorbidities, medication usage, and physical and laboratory predictors. Outcomes: eGFRdiff, defined as eGFRcys minus eGFRcr, categorized into 3 levels: lower eGFRcys (eGFRdiff, less than -15 mL/min/1.73 m2), concordant eGFRcys and eGFRcr (eGFRdiff, -15 to < 15 mL/min/1.73 m2), and lower eGFRcr (eGFRdiff, ≥15 mL/min/1.73 m2). Analytical Approach: Multinomial logistic regression models were constructed to identify predictors of lower eGFRcys or lower eGFRcr. We developed 2 prediction models comprising 375,175 participants: (1) a clinical model using clinically available variables and (2) an enriched model additionally including lifestyle variables. The models were internally validated in an additional 93,794 participants. Results: Mean ± standard deviation of eGFRcys was 88 ± 16 mL/min/1.73 m2, and eGFRcr was 95 ± 13 mL/min/1.73 m2; 25% and 5% of participants were in the lower eGFRcys and lower eGFRcr groups, respectively. In the multivariable enriched model, strong predictors of lower eGFRcys were older age, male sex, South Asian ethnicity, current smoker (vs never smoker), history of thyroid dysfunction, chronic inflammatory disease, steroid use, higher waist circumference and body fat, and urinary albumin-creatinine ratio >300 mg/g. Odds ratio estimates for these predictors were largely inverse of those in the lower eGFRcr group. The model's area under the curve was 0.75 in the validation set, with good calibration (1.00). Limitations: Limited generalizability. Conclusions: This study highlights the multitude of demographic, lifestyle, and health characteristics that are associated with large eGFRdiff. The clinical model may identify individuals who are likely to have discrepant eGFR values and thus should be prioritized for cystatin C testing.

Estimated glomerular filtration rate (eGFR) based on cystatin C and creatinine may differ substantially within an individual. Although most clinicians are aware that creatinine is influenced by muscle mass, there are additional numerous lifestyle and health characteristics that may affect serum concentrations of either biomarker. Our analyses of 468,969 individuals in the UK Biobank identified independent predictors of large differences between eGFR based on cystatin C and eGFR based on creatinine, which may inform the interpretation of discrepant eGFR values within an individual. We developed models that may be implemented at a population level to help health systems identify individuals who are likely to have large differences between eGFR based on cystatin C and eGFR based on creatinine and thus should be prioritized for cystatin C testing.

U-shaped relationship between fasting blood glucose and urinary albumin-to-creatinine ratio in the general United States population.

Objective: The current controversy surrounding the association between fasting blood glucose (FBG) and albuminuria necessitates further investigation. Hence, the primary objective of this study was to examine the relationship between FBG and urinary albumin-to-creatinine ratio (UACR). Methods: A cohort of complete data from National Health and Nutrition Examination Survey (NHANES) participants (1999-2020) was analyzed. Linear regression analyses and a generalized additive model explored the association between FBG and UACR. Furthermore, the stability of this relationship across different populations was assessed. Results: The study involved a total of 20,264 participants who were identified as U.S. citizens. By employing linear regression analysis, a statistically significant relationship was observed between elevated FBG levels and an increase in UACR (P<0.0001). Additionally, using a generalized additive model analysis, a U-shaped correlation between FBG and UACR was identified. Further examination using threshold effect analysis indicated a turning point for FBG at 5.44 mmol/L. A noteworthy finding in multiple populations is the consistent U-shaped association between FBG and UACR, except for individuals with serum uric acid levels ≥420 µmol/L and those who refrain from alcohol consumption. Conclusion: The general U.S. population has a U-shaped nonlinear relationship between FBG and UACR.

Understanding the limitations of your assay using EQA data with serum creatinine as an example.

OBJECTIVES: Laboratories need to take into consideration the specificity and imprecision of assays not only in verification, but also of quality assessment. This study investigates the composition of serum used in EQA materials by comparing material from a single and multiple donors (pooled material), across multiple methods, using creatinine as an example. METHODS: Sixteen different serum matrices were distributed as 36 specimens through the UK NEQAS for Acute and Chronic Kidney Disease Scheme from March 2022 to March 2023. Male-only and female-only serum was used as single donations, pooled donations, unmanipulated or with added exogenous creatinine. Specimens were distributed to primarily UK participants (approximately n=500) for creatinine analysis. Data has been reviewed by method compared to the enzymatic creatinine method principle mean. RESULTS: From the 16 different matrices, only the enzymatic creatinine assay systems from Roche Cobas and Siemens Atellica met the minimum acceptable bias goal, from biological data, of 5.6 %, in all specimens. Pooled material showed less variation in bias across all methods. CONCLUSIONS: Since Laboratories invest a lot of time and money in quality management, they need to know the limitations of their assays so that they are not investigating 'apparent' EQA/IQC problems which are purely due to non-specific, imprecise assay, rather than an analytical issue in their laboratory. When large numbers of individual donations are combined, interferents are essentially diluted out. Therefore, if EQA material is of this type it will be very difficult to determine the actual assay's bias and variability.

Comparative efficacy of sodium glucose cotransporter-2 inhibitors in the management of type 2 diabetes mellitus: A real-world experience.

BACKGROUND: Sodium glucose cotransporter-2 inhibitors (SGLT-2i) are a class of drugs with modest antidiabetic efficacy, weight loss effect, and cardiovascular benefits as proven by multiple randomised controlled trials (RCTs). However, real-world data on the comparative efficacy and safety of individual SGLT-2i medications is sparse. AIM: To study the comparative efficacy and safety of SGLT-2i using real-world clinical data. METHODS: We evaluated the comparative efficacy data of 3 SGLT-2i drugs (dapagliflozin, canagliflozin, and empagliflozin) used for treating patients with type 2 diabetes mellitus. Data on the reduction of glycated hemoglobin (HbA1c), body weight, blood pressure (BP), urine albumin creatinine ratio (ACR), and adverse effects were recorded retrospectively. RESULTS: Data from 467 patients with a median age of 64 (14.8) years, 294 (62.96%) males and 375 (80.5%) Caucasians were analysed. Median diabetes duration was 16.0 (9.0) years, and the duration of SGLT-2i use was 3.6 (2.1) years. SGLT-2i molecules used were dapagliflozin 10 mg (n = 227; 48.6%), canagliflozin 300 mg (n = 160; 34.3%), and empagliflozin 25 mg (n = 80; 17.1). Baseline median (interquartile range) HbA1c in mmol/mol were: dapagliflozin - 78.0 (25.3), canagliflozin - 80.0 (25.5), and empagliflozin - 75.0 (23.5) respectively. The respective median HbA1c reduction at 12 months and the latest review (just prior to the study) were: 66.5 (22.8) & 69.0 (24.0), 67.0 (16.3) & 66.0 (28.0), and 67.0 (22.5) & 66.5 (25.8) respectively (P < 0.001 for all comparisons from baseline). Significant improvements in body weight (in kilograms) from baseline to study end were noticed with dapagliflozin - 101 (29.5) to 92.2 (25.6), and canagliflozin 100 (28.3) to 95.3 (27.5) only. Significant reductions in median systolic and diastolic BP, from 144 (21) mmHg to 139 (23) mmHg; (P = 0.015), and from 82 (16) mmHg to 78 (19) mmHg; (P < 0.001) respectively were also observed. A significant reduction of microalbuminuria was observed with canagliflozin only [ACR 14.6 (42.6) at baseline to 8.9 (23.7) at the study end; P = 0.043]. Adverse effects of SGLT-2i were as follows: genital thrush and urinary infection - 20 (8.8%) & 17 (7.5%) with dapagliflozin; 9 (5.6%) & 5 (3.13%) with canagliflozin; and 4 (5%) & 4 (5%) with empagliflozin. Diabetic ketoacidosis was observed in 4 (1.8%) with dapagliflozin and 1 (0.63%) with canagliflozin. CONCLUSION: Treatment of patients with SGLT-2i is associated with statistically significant reductions in HbA1c, body weight, and better than those reported in RCTs, with low side effect profiles. A review of large-scale real-world data is needed to inform better clinical practice decision making.

The role of online hemodiafiltration with endogenous reinfusion in the treatment of systemic lupus erythematosus activity resistant to conventional therapy.

Introduction: Lupus is a diverse autoimmune disease with autoantibody formation. Lupus nephritis carries a grave prognosis. Complement involvement, namely, C1q deficiency, is linked to activity and renal involvement and could help in their assessment. LN therapies include plasma exchange, immune adsorption, and probably hemodiafiltration with online endogenous reinfusion (HFR), together with traditional immunosuppressive therapies. Aim: The aim of this study was to evaluate the role of HFR in improving signs and symptoms of systemic lupus erythematosus (SLE) activity and laboratory parameters in cases not responding to traditional immunosuppressive therapy. Settings and design: A controlled clinical study was conducted on 60 patients with lupus from Group A that was subdivided into two groups: cases 1 (47 patients), those who received traditional medical treatment, and cases 2 (13 patients), those who underwent HFR in addition to medical treatment. Group B consisted of two subgroups: control 1, composed of 20 healthy age- and sex-matched volunteers, and control 2, consisting of 10 cases with different glomerular diseases other than lupus. Methods and materials: Serum C1q was determined before and after the HFR as well as induction by medical treatment. Disease activity was assessed using SLEDAI-2K with a responder index of 50; quality of life was assessed using SLEQOL v2, and HFR was performed for the non-responder group. Results: C1q was lower in cases. It can efficiently differentiate between SLE patients and healthy controls with a sensitivity of 81.67% and a specificity of 90%. It can also efficiently differentiate between SLE patients and the control 2 group (non-lupus patients with renal glomerular disease) with a sensitivity of 83.33% and a specificity of 100%. C1q was more consumed in proliferative lupus, and correlated with anti-ds DNA, C3, and C4. Conclusions: C1q efficiently discriminates lupus patients and correlates with proliferative forms. HFR might ameliorate lupus activity and restore C1q.

The Association Between Thyroid Hormones and Renal Function in Euthyroid Chinese Individuals: A Population-Based Cross-Sectional Study.

Objective This population-based cross-sectional study aimed to investigate the association between thyroid hormones and renal function in euthyroid Chinese individuals, as the relationship between thyroid hormones and renal function in this population remains unclear. Methods A total of 661 participants were included in the study after excluding individuals with thyroid diseases, incomplete clinical measurements, or those taking medications affecting thyroid function. Participants were categorized into three groups based on serum thyroid hormone and antibody levels. The study adjusted for covariates and assessed the glomerular filtration rate (GFR) and urine albumin-to-creatinine ratio (ACR) in relation to thyroid hormone levels. Results After adjusting for covariates, the study found a significant increase in GFR in the middle and highest tertiles of free triiodothyronine (FT3) and the highest tertile of total triiodothyronine (TT3). Serum FT3 and TT3 levels were significantly associated with GFR. Additionally, the study observed a significantly lower GFR in the highest tertile of thyroid-stimulating hormone (TSH) compared to the lowest tertile. However, thyroid hormone and antibody levels were not associated with the ACR. Furthermore, the highest tertiles of TT3 and total thyroxine (TT4) were associated with a decreased risk of chronic kidney disease (CKD). Conclusion In our study among euthyroid Chinese individuals, we observed a significant association between thyroid function and GFR. Specifically, lower FT3, TT3, and higher TSH were associated with reduced GFR, indicating a potential role for thyroid hormones in maintaining renal function. Furthermore, lower levels of TT3 and TT4 were associated with an increased risk of CKD. These findings suggest a direct link between thyroid and renal function, even in euthyroid individuals, emphasizing the need for further investigation to elucidate the underlying mechanisms and potential therapeutic implications.

Lower serum uric acid to serum creatinine ratio as a predictor of poor functional outcome after mechanical thrombectomy in acute ischaemic stroke.

BACKGROUND AND PURPOSE: The ratio of serum uric acid (SUA) to serum creatinine (SCr), representing normalized SUA for renal function, is associated with functional outcome in acute ischaemic stroke (AIS) patients. However, its effect on AIS patients undergoing mechanical thrombectomy (MT) remains unknown. This study aimed to investigate the influence of the SUA/SCr ratio on clinical outcome in MT-treated AIS patients. METHODS: Acute ischaemic stroke patients who underwent MT were continuously enrolled from January 2018 to June 2023. Upon admission, SUA and SCr levels were recorded within the initial 24 h. Stroke severity was determined using the National Institutes of Health Stroke Scale (NIHSS) score. Clinical outcome included poor functional outcome (modified Rankin Scale score >2) at 90 days, symptomatic intracranial haemorrhage and death. RESULTS: Amongst 734 patients, 432 (58.8%) exhibited poor functional outcome at 90 days. The SUA/SCr ratio exhibited a negative correlation with NIHSS score (ρ = -0.095, p = 0.010). Univariate analysis revealed a significant association between SUA/SCr ratio and poor functional outcome. After adjusting for confounders, the SUA/SCr ratio remained an independent predictor of functional outcome (adjusted odds ratio 0.348, 95% confidence interval 0.282-0.428, p < 0.001). Receiver operating characteristic curve analysis highlighted the ability of the SUA/SCr ratio to predict functional outcome, with a cutoff value of 3.62 and an area under the curve of 0.757 (95% confidence interval 0.724-0.788, p < 0.001). CONCLUSION: The SUA/SCr ratio is correlated with stroke severity and may serve as a predictor of 90-day functional outcome in AIS patients undergoing MT.

Predictive effect of estimated glomerular filtrate rate by creatinine or cystatin C on mortality in patients with coronary artery disease.

BACKGROUND: Renal dysfunction leads to poor prognosis of patients with coronary artery disease (CAD). Current studies have reported the prognosis or mortality of various diseases using different estimated glomerular filtrate rate (eGFR) formulas, while the performance of these equations is unclear in CAD patients. We aim to evaluate the predict effect of creatinine-based eGFR (eGFRcr), cystatin C-based eGFR (eGFRcys), and both creatinine and cystatin C-based eGFR (eGFRcr-cys) in CAD patients. METHODS: A total of 23,178 patients with CAD were included from CIN-II cohort study. The association of eGFRcr, eGFRcys and eGFRcr-cys with cardiovascular and all-cause mortality was detected by Cox regression analysis. The predictive effect of eGFRcr, eGFRcys and eGFRcr-cys on mortality was assessed. RESULTS: During a median follow up of 4.3 years, totally 2051 patients (8.8%) experience all-cause mortality, of which 1427 patients (6.2%) died of cardiovascular disease. For the detection of cardiovascular mortality among CAD patients, eGFRcr-cys had high discriminatory capacity with area under the curve (AUC) in receiver operator characteristic analysis of 0.730, which was significantly better than eGFRcr (AUC = 0.707, p < 0.001) and eGFRcys (AUC = 0.719, p < 0.001). Similar results were observed in all-cause mortality. Restricted cubic spline showed a U-shaped association between eGFRcr and all outcomes in patients with both reduced and supranormal eGFR levels, while a L-shaped association in eGFRcys and eGFRcr-cys. CONCLUSIONS: Estimated GFR based on both creatinine and cystatin C has highest predictive effect for cardiovascular and all-cause mortality among CAD patients. Meanwhile, supranormal eGFRcr may indicate a higher risk of mortality.

Association between serum creatinine and 30 days all-cause mortality in critically ill patients with non-traumatic subarachnoid hemorrhage: analysis of the MIMIC-IV database.

Background: Serum creatinine is a prognostic marker for various conditions, but its significance of spontaneous subarachnoid hemorrhage is still poorly understood. This study aims to elucidate the correlation between admission serum creatinine (sCr) levels and all-cause mortality within 30 days among individuals affected by non-traumatic subarachnoid hemorrhage (SAH). Methods: This cohort study included 672 non-traumatic SAH adults. It utilized data from the MIMIC-IV database from 2008 to 2019. The patients' first-time serum creatinine was recorded. Subsequently, an examination of the 30-day all-cause mortality was conducted. Employing a multiple logistic regression model, a nomogram was constructed, while the association between sCr and 30-day all-cause mortality was evaluated using Kaplan-Meier survival curves. The calibration curve was employed to assess the model's performance, while subgroup analysis was employed to examine the impact of additional complications and medication therapy on outcomes. Results: A total of 672 patients diagnosed with non-traumatic subarachnoid hemorrhage were included in the study. The mortality rate within this timeframe was found to be 24.7%. Multiple logistic regression analysis revealed that sCr served as an independent prognostic indicator for all-cause mortality within 30 days of admission for SAH patients [OR: 2(1.18-3.41); p = 0.01]. A comprehensive model was constructed, incorporating age, sCr, white blood cell count (WBC), glucose, anion gap, and partial thromboplastin time (PTT), resulting in a prediction model with an AUC value of 0.806 (95% CI: 0.768, 0.843), while the AUC for the test set is 0.821 (95% CI: 0.777-0.865). Conclusion: Creatinine emerges as a significant biomarker, closely associated with heightened in-hospital mortality in individuals suffering from SAH.

Dry eye rate and its relationship with disease stage in patients with primary hypertension: a cross-sectional study in Vietnam.

AIM: To determine the dry eye (DE) rate and its relationship with disease stage in patients with primary hypertension. METHODS: A cross-sectional study included 432 patients with primary hypertension (with an equal number of patients in each group: 144 in stage I, II, and III hypertension) and 144 healthy subjects as a control group. The Ocular Surface Disease Index (OSDI) and Schirmer I test without anesthetics were conducted on all 576 subjects. Subjects with OSDI scores <13 and Schirmer I values equal to or under 10 mm were diagnosed with DE. RESULTS: The ratio of DE in hypertension patients was higher than in the control group (41.7% versus 18.8%; P<0.001). The proportion of patients with DE increased gradually according to the hypertension stage: 27.1% in stage I, 40.3% in stage II, and 57.6% in stage III, P<0.001. Age, duration of hypertension, plasma urea, creatinine, and high-sensitivity C-reactive protein (CRP-hs) levels in hypertension patients with DE were higher than those without DE, P<0.001. Advanced age, a long duration of hypertension, diabetes mellitus, elevated plasma creatinine, and CRP-hs levels were independent factors associated with DE in primary hypertension patients, P<0.001. CONCLUSION: DE is a common disorder associated with advanced age, a long duration of hypertension, diabetes mellitus, elevated plasma CRP-hs, and creatinine levels in patients with primary hypertension.

A candidate panel of eight urinary proteins shows potential of early diagnosis and risk assessment for diabetic kidney disease in type 1 diabetes.

Diabetic kidney disease (DKD) poses a significant health challenge for individuals with diabetes. At its initial stages, DKD often presents asymptomatically, and the standard for non-invasive diagnosis, the albumin-creatinine ratio (ACR), employs discrete categorizations (normal, microalbuminuria, macroalbuminuria) with limitations in sensitivity and specificity across diverse population cohorts. Single biomarker reliance further restricts the predictive value in clinical settings. Given the escalating prevalence of diabetes, our study uses proteomic technologies to identify novel urinary proteins as supplementary DKD biomarkers. A total of 158 T1D subjects provided urine samples, with 28 (15 DKD; 13 non-DKD) used in the discovery stage and 131 (45 DKD; 40 pDKD; 46 non-DKD) used in the confirmation. We identified eight proteins (A1BG, AMBP, AZGP1, BTD, RBP4, ORM2, GM2A, and PGCP), all of which demonstrated excellent area-under-the-curve (AUC) values (0.959 to 0.995) in distinguishing DKD from non-DKD. Furthermore, this multi-marker panel successfully segregated the most ambiguous group (microalbuminuria) into three distinct clusters, with 80% of subjects aligning either as DKD or non-DKD. The remaining 20% exhibited continued uncertainty. Overall, the use of these candidate urinary proteins allowed for the better classification of DKD and offered potential for significant improvements in the early identification of DKD in T1D populations.

Miscarriage-Related Acute Kidney Injury: A Case Report.

Background: Pregnancy-related acute kidney injury (Pr-AKI) is associated with significant maternal and fetal morbidity and mortality, with a three- to four-fold increase in perinatal mortality. Pr-AKI can arise from various obstetric complications, such as hyperemesis gravidarum, septic abortion, hypertensive disorders of pregnancy, pyelonephritis, and antiphospholipid antibody syndrome. Therefore, early diagnosis and appropriate intervention, including the identification of the underlying etiology, are important to effectively manage Pr-AKI. Therefore, we report a case of Pr-AKI after early miscarriage in a patient without hyperemesis gravidarum or septic abortion whose renal function gradually improved postoperatively for miscarriage. Case Presentation: A 34-year-old primigravid woman was referred to us for perinatal management at 6 weeks of gestation. Unfortunately, she was diagnosed with miscarriage 1 week later. The patient had no history of hyperemesis gravidarum or septic abortion; however, she developed oliguria, and her serum creatinine and blood urea nitrogen levels were abnormally increased. Consequently, she underwent a renal biopsy to evaluate renal dysfunction, which indicated tubulointerstitial damage. The patient also underwent manual vacuum aspiration for a miscarriage. Postoperatively, her urine output increased, and her renal function improved. She was determined to have experienced Pr-AKI due to her miscarriage. Conclusion: Our patient had Pr-AKI after a miscarriage in the absence of other causes. This case report highlights the presence of unknown causes of Pr-AKI, warranting further research for the development of preventive interventions.