Alpha-Klotho protein in systemic lupus erythematosus.

OBJECTIVES: Alpha-Klotho protein (α-Klotho) is an essential component of endocrine fibroblast growth factor receptor complexes that governs multiple metabolic processes including aging-related disorders, diabetes, cancer, arteriosclerosis, and chronic kidney disease. Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that can affect almost any organ in the body and in which multiple pathophysiological abnormalities are observed. In the present work, our objective was to study whether the serum levels of α-Klotho differ between patients with SLE and controls, and how this protein is related to the clinical and laboratory characteristics of the disease. METHODS: Cross-sectional study that included 364 women, 195 of them diagnosed with SLE and 169 sex- and age-matched controls. Circulating α-Klotho was analysed in SLE patients and controls. A multivariable analysis was performed to assess whether α-Klotho differs between patients and controls, and to study its relationship with SLE features. RESULTS: No differences were found in α-Klotho levels between SLE patients and controls, both in univariable and multivariable analyses. Disease-related data like SLE duration, acute phase reactants, activity, severity and damage indices, and autoantibodies profile were not significantly associated with serum levels of α-Klotho. However, the use of prednisone and the presence of musculoskeletal manifestations were significantly related to higher α-Klotho serum levels. CONCLUSIONS: α-Klotho protein serum levels do not differ between patients with SLE and controls. Nevertheless, SLE patients taking prednisone or those with musculoskeletal manifestations show significantly higher circulating levels of α-Klotho.

High blood Fas concentrations in non-survivor patients with traumatic brain injury.

Fas is one of the main death receptors of the extrinsic pathway of apoptosis. A study has reported higher Fas expression in brain samples of non-surviving TBI patients than in survivors. The objective of our current study was to determine whether there is an association between Fas concentrations in blood and mortality of isolated TBI patients. Patients with severe TBI [< 9 points in Glasgow Coma Scale (GCS)] and isolated TBI (< 10 non-cranial aspects points on the Injury Severity Score) were included from 5 Intensive Care Units. We measured serum Fas concentrations on the day of TBI. Non-surviving (n = 23) compared to surviving patients (n = 57) had higher age (p = 0.01), lower GCS (p = 0.001), higher APACHE-II score (p < 0.001), higher ICP (p = 0.01), higher CT findings with high risk of death (p = 0.02) and higher serum Fas concentrations (p < 0.001). We found in regression analyses an association between serum Fas levels and mortality of TBI patients after controlling for CT findings, age and CGS (OR = 1.006; 95% CI 1.001-1.011; p = 0.02), and after controlling for CT findings, ICP and APACHE-II (OR = 1.007; 95% CI 1.001-1.012; p = 0.02). Thus, the most interesting and novel finding in this study is the association between high blood Fas concentrations and mortality in TBI patients.

Apolipoprotein C-III in patients with systemic lupus erythematosus.

BACKGROUND: Systemic lupus erythematosus (SLE) has been associated with atherosclerotic cardiovascular disease (CV) and an altered lipid profile. High levels of apolipoprotein C-III (ApoC3) are associated with elevated triglyceride levels and an increased risk of CV. In the present study, we aimed to study circulating ApoC3 in patients with SLE and describe its relationship with the manifestations of the disease. METHODS: This is a cross-sectional study that included 186 patients with SLE. Disease-related data, CV comorbidity, full lipid profile, and serum levels of ApoC3 were assessed. A multivariable regression analysis was performed to study how ApoC3 was related to SLE features. RESULTS: Classic CV risk factors were significantly and strongly associated with circulating ApoC3. After a fully multivariable analysis that included classic CV risk factors and lipid profile molecules, SLICC damage (beta coef. 0.10 [95% CI 0.02-0.19] mg/dl, 0.020) and Katz severity (beta coef. 0.11 [95% CI 0.03-0.19] mg/dl, p = 0.011) indices and SLEDAI activity score (beta coef. 0.05 [95% CI 0.05-0.08] mg/dl, p = 0.004) were all independently associated with higher levels of circulating ApoC3. CONCLUSION: Among SLE patients, disease activity, severity, and disease damage are independently associated with higher ApoC3 serum levels.

Key Molecules of Triglycerides Pathway Metabolism Are Disturbed in Patients With Systemic Lupus Erythematosus.

Background: Elevated triglycerides or triglyceride-rich lipoproteins are an additional cause of cardiovascular (CV) disease. Given that patients with systemic lupus erythematosus (SLE) have a high prevalence of premature CV disease and show an altered lipid profile, our objective was to study whether three molecules that play a central role in the triglyceride metabolism: apolipoprotein C-III (ApoC3), angiopoietin-like protein 4 (ANGPLT4), and lipoprotein lipase (LPL) differ between SLE patients and controls, and how they are related to disease characteristics, including disease damage. Methods: Cross-sectional study that included 347 women, 185 of them diagnosed with SLE and 162 age-matched controls. ANGPTL4, ApoC3 and LPL, and standard lipid profiles were analyzed in SLE patients and controls. A multivariable analysis was performed to assess whether ANGPTL4, ApoC3 and LPL molecules differ between patients and controls and to study their relationship with SLE disease damage. Results: After fully multivariable analysis that included classic CV risk factors, and the modifications that the disease itself produces over the lipid profile, it was found that ApoC3 was significantly lower (beta coef. -1.2 [95%CI -1.6- -0.8) mg/dl, <0.001), and ANGPTL4 (beta coef. 63 [95%CI 35-90] ng/ml, <0.001) and LPL (beta coef. 79 [95%CI 30-128] ng/ml, p=0.002) significantly higher in patients with SLE compared to controls. Disease damage score was significantly and independently associated with higher serum levels of LPL (beta coef. 23 [95%CI 10-35] ng/ml, p=0.001). Mediation analysis suggested that the relationship between disease damage and LPL was direct and not mediated by ApoC3 or ANGPLT4. Conclusion: The ApoC3, ANGPLT4 and LPL axis is disrupted in patients with SLE. Disease damage explains this disturbance.

Estimated GFR in autosomal dominant polycystic kidney disease: errors of an unpredictable method.

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) causes about 10% of cases of end stage renal disease. Disease progression rate is heterogeneous. Tolvaptan is presently the only specific therapeutic option to slow kidney function decline in adults at risk of rapidly progressing ADPKD with chronic kidney disease (CKD) stages 1-4. Thus, a reliable evaluation of kidney function in patients with ADPKD is needed. METHODS: We evaluated the agreement between measured (mGFR) and estimated glomerular filtration rate (eGFR) by 61 formulas based on creatinine and/or cystatin-C (eGFR) in 226 ADPKD patients with diverse GFR values, from predialysis to glomerular hyperfiltration. Also, we evaluated whether incorrect categorization of CKD using eGFR may interfere with the indication and/or reimbursement of Tolvaptan treatment. RESULTS: No formula showed acceptable agreement with mGFR. Total Deviation Index averaged about 50% for eGFR based on creatinine and/or cystatin-C, indicating that 90% of the estimations of GFR showed bounds of error of 50% when compared with mGFR. In 1 out of 4 cases with mGFR < 30 ml/min, eGFR provided estimations above this threshold. Also, in half of the cases with mGFR between 30 and 40 ml/min, formulas estimated values < 30 ml/min. CONCLUSIONS: The evaluation of renal function with formulas in ADPKD patients is unreliable. Extreme deviation from real renal function is quite frequent. The consequences of this error deserve attention, especially in rapid progressors who may benefit from starting treatment with tolvaptan and in whom specific GFR thresholds are needed for the indication or reimbursement. Whenever possible, mGFR is recommended.

Blood Bcl-2 levels to predict the mortality of septic patients.

Aim: To determine whether blood concentrations of Bcl-2 during the 1st week of sepsis could help predict mortality. Methods: Serum Bcl-2 concentrations were determined at the 1st, 4th and 8th days of sepsis diagnosis. Results: Thirty-day surviving patients (n = 168) showed higher serum Bcl-2 levels at the 1st (p = 0.002), 4th (p < 0.001) and 8th days (p < 0.001) of sepsis diagnosis than non-surviving patients (n = 91). An association between serum Bcl-2 concentrations at the 1st (p = 0.003), 4th (p < 0.001) and 8th days (p = 0.01) and 30-day mortality after controlling for diabetes mellitus, Sepsis-related Organ Failure Assessment, lactic acid and age was found in the multiple logistic regression analysis. Conclusions: The novel finding is that blood Bcl-2 concentrations at any time in the 1st week of sepsis are associated with mortality.

Estimated GFR Slope in Kidney Transplant Patients: When the Error Is Random.

BACKGROUND: The evaluation of renal function changes over time is crucial in day-to-day renal transplant care, and the slope of renal function is a major outcome in clinical trials. Little is known about the reliability of estimated glomerular filtration rate (eGFR) in reflecting real glomerular filtration rate (GFR) changes. METHODS: We analyzed the variability of eGFR slope by 63 equations in estimating measured GFR (mGFR) changes in 110 renal transplant patients. The agreement between eGFR and mGFR slopes was evaluated by the concordance correlation coefficient and the limits of agreement. Patients were grouped based on mGFR slope in rapid GFR loss: faster than -3 mL/min/y; stable renal function: -3 to +3 mL/min/y; and improvement in GFR: higher than +3 mL/min/y. RESULTS: Concordance correlation coefficient averaged 0.36 and limits of agreement ±10 mL/min/y, indicating very poor agreement between eGFR and mGFR slopes. The eGFR slope classified patients into the same group of mGFR slope only in 25% of the cases. In about two-thirds of patients, the eGFR slope was either markedly faster or slower than the mGFR slope. In half of these cases, the discrepancy between mGFR and eGFR slopes was ≥50%. CONCLUSIONS: Formulas are neither accurate nor precise in reflecting real GFR decline in renal transplant patients, making them unreliable for clinical practice and trials.

Association between serum concentrations of anti-apoptotic B-cell lymphoma-2 protein and traumatic brain injury mortality.

BACKGROUND: There are scarce and contradictory data existing about B-cell lymphoma 2 (Bcl2), one of the Bcl2 family of anti-apoptotic proteins, in traumatic brain injury (TBI) patients. Thus, the objective of this study was to analyze whether blood concentrations of Bcl2 are associated with mortality. METHODS: Patients with isolated and severe TBI, defined as <10 points of the Injury Severity Score (ISS) in non-cranial aspects and <9 points in Glasgow Coma Scale (GCS), were included. This was an observational and prospective study carried out in five Intensive Care Units. Serum Bcl2 concentrations on day 1 of TBI were determined. RESULTS: Serum Bcl2 concentrations were lower (p < 0.001) in surviving patients (n = 59) compared to non-survivors (n = 24). We found an association between serum Bcl2 levels and mortality controlling for age and GCS (OR = 1.149; 95% CI = 1.056-1.251; p = 0.001) and controlling for computer tomography findings (OR = 1.147; 95% CI = 1.056-1.246; p = 0.001). CONCLUSIONS: This study reports for the first time an association between serum Bcl2 levels and 30-day mortality in TBI patients.

Apolipoprotein C3 and beta-cell dysfunction are linked in patients with systemic lupus erythematosus.

OBJECTIVES: Systemic lupus erythematosus (SLE) has been associated with insulin resistance and beta-cell dysfunction. Apolipoprotein C3 (ApoC3) is a component of very low-density lipoproteins. Since ApoC3 has been linked to beta-cell impairment in the general population, in this study we aimed to discover if this lipoprotein is related to glucose homeostasis disturbance in patients with SLE. METHODS: One hundred and forty non diabetic patients with SLE who had a glycaemia lower than 110 mg/dl were recruited. Insulin, C-peptide, and ApoC3 were assessed. Insulin resistance and beta-cell function were calculated using the Homeostasis Model Assessment (HOMA2) indices. A multivariable regression analysis was performed to study the relationship of ApoC3 to those molecules and indices adjusting for classical factors associated with insulin resistance that included glucocorticoids. RESULTS: In the multivariable regression analysis that included prednisone intake, a significant relation of ApoC3 to C-peptide was found (beta coef. 0.27 [95%CI 0.03-0.51) ng/ml, p=0.030). Similarly, ApoCa3 was associated with higher degree of beta-cell dysfunction (HOMA2-%B) although in this case statistical significance was not achieved (beta coef. 8 [95%CI-1-18], p=0.086). This relationship was not found with serum insulin levels or IR indices. Furthermore, in the univariable analysis, but not after multivariable adjustment, the disease damage score was found to significantly mediate the effect of ApoC3 on circulating C-peptide. and HOMA2-%B. CONCLUSIONS: Beta-cell dysfunction and ApoC3 are linked in patients with SLE.

Estimated glomerular filtration rate by formulas in patients with cirrhosis: An unreliable procedure.

BACKGROUND & AIMS: In cirrhosis, the reliability of formulas that estimate renal function, either those specifically developed in this population or the classic equations, has not been properly quantified. We studied the agreement between estimated (eGFR) and measured glomerular filtration rate (mGFR) in cirrhosis. METHODS: Renal function was estimated with 56 formulas including specific equations: Glomerular Filtration Rate Assessment in Liver Disease (GRAIL), Royal Free Hospital Cirrhosis (RFHC) and Mindikoglu-eGFR, and measured with a gold standard procedure; plasma clearance of iohexol using dried blood spots sampling in a group of cirrhotics. The agreement eGFR-mGFR was evaluated with specific tests: total deviation index (TDI), concordance correlation coefficient (CCC) and coverage probability (CP). We defined acceptable agreement as values: TDI < 10%, CCC ≥ 0.9 and CP > 90%. RESULTS: A total of 146 patients (age 65 ± 9 years, 81% male) were evaluated; 61 (42%) Child A, 67 (46%) Child B and 18 (12%) Child C. Median MELD-Na was 14 (9-15). The agreement between eGFR and mGFR was poor: TDI averaged was of 73% (90% of the estimations ranged from ±73% of mGFR); CCC averaged was 0.7 indicating low concordance and CP averaged 22% indicating that 78% of the estimations have an error > 10%. Specific formulas showed also poor agreement: TDI was 82%, 70% and 37% for the GRAIL, RFHC and Mindikoglu equations, respectively. CONCLUSIONS: Overall, formulas poorly estimated renal function in cirrhotic patients. Specific formulas designed for cirrhosis did not outperform classic equations. eGFR must be considered with caution in cirrhotic patients.

Mortality prediction of patients with spontaneous intracerebral hemorrhage by serum soluble Fas ligand concentrations.

BACKGROUND: A study of patients with spontaneous intracerebral hemorrhage (SIH) found a higher content of Fas ligand in the perihematomic brain area compared to healthy brain areas. The objective of this study was to analyze whether blood soluble Fas ligand (sFasL) concentrations could be used to estimate the prognosis of SIH patients. METHODS: Observational and prospective study performed in five Spanish Intensive Care Units. Patients with severe supratentorial SIH, defined as Glasgow Coma Scale (GCS) <9, were included. Serum sFasL levels were determined at the time of diagnosis of severe SIH. Mortality at 30 days was the end-point study. RESULTS: Surviving SIH patients (n = 41) compared to nonsurvivors (n = 38) showed lower serum sFasL levels (p < 0.001). The area under curve of mortality prediction for serum sFasL levels was 0.79 (95% CI = 0.70-0.89; p < 0.001). Multiple logistic regression analysis found an association of serum sFasL concentrations with 30-day mortality (ORo = 1,034; 95% CI = 1,010-1,058; p = 0,006) after controlling for midline shift, early hematoma evacuation, and intracerebral hemorrhage score. CONCLUSIONS: The capability of serum sFasL to predict SIH patient mortality is the main novel finding of our study. ABBREVIATIONS: APACHE II: Acute Physiology and Chronic Health Evaluation; aPTT: activated partial thromboplastin time; FIO2: fraction of inspired oxygen; GCS: Glasgow Coma Scale; ICU: Intensive Care Unit; INR: international normalized ratio; PaO2: pressure of arterial oxygen.

Blood soluble Fas concentrations and ischemic stroke patient mortality.

BACKGROUND: Fas is a major receptor for cell death by apoptosis. Higher blood concentrations of soluble Fas (sFas) have been reported in patients with ischemic stroke compared to control subjects. The aim of this study was to explore the existence or not of an association between blood sFas concentrations and mortality in patients with ischemic stroke. METHODS: This study included patients admitted to Intensive Care Units with severe and malignant middle cerebral artery infarction (MCAI), defined as acute infarction, in more than 50% of this territory on computed tomography and less than 9 points on the Glasgow Coma Scale (GCS). Serum sFas levels were determined at the time of diagnosis of MMCAI. RESULTS: Non-surviving severe MMCAI patients (n = 27) showed lower platelet count (p = 0.004), higher serum sFas (p < 0.001), and lower GCS (p = 0.001) compared to surviving patients (n = 27). Multiple logistic regression found an association of serum sFas levels and mortality at 30 days (OR = 1.015; 95% CI = 1.002-1.027; p = 0.02) after control for CGS and platelet count. CONCLUSIONS: The main novelty of our study was the existence of an association between high blood sFas concentrations and mortality in patients with ischemic stroke.

Low blood caspase-8 levels in survivor patients of traumatic brain injury.

OBJECTIVE: High concentrations of caspase-8 (main initiator caspase of the extrinsic pathway of apoptosis) have been found in brain tissue of patients with traumatic brain injury (TBI) and in the blood of patients with different diseases. However, blood caspase-8 concentrations in TBI patients have not been reported. Therefore, our aim was to analyze whether blood caspase-8 concentrations are associated with mortality in TBI patients. METHOD: Patients with isolated and severe TBI were included. TBI was considered isolated if it showed an Injury Severity Score (ISS) <10 points on non-cranial aspects. TBI was considered severe if it showed a Glasgow Coma Scale (GCS) <9 points. This prospective observational study was conducted in 5 Intensive Care Units. Serum caspase-8 concentrations were measured on day 1 of TBI. RESULTS: Surviving patients (n=59) had lower age (p=0.004), higher GCS (p=0.001), lower APACHE-II score (p<0.001), lower high-risk-of-death computed tomography (CT) findings (p=0.02), lower intracranial pressure (ICP) (p=0.01), and lower serum caspase-8 concentrations (p<0.001) than non-surviving patients (n=24). An association was found between serum caspase-8 levels and mortality after controlling for CT findings, GCS, and age (OR=1.037; 95% CI=1.013-1.062; p=0.002), and after controlling for CT findings, APACHE-II, and ICP (OR=1.042; 95% CI=1.013-1.071; p=0.004) in multiple logistic regression. CONCLUSIONS: To our knowledge, this is the first series describing blood caspase-8 concentrations in patients with TBI. The association of high blood caspase-8 concentrations with mortality was the main new finding of the study. However, further investigations are needed to validate the preliminary results of our study.

High Serum Soluble Fas Ligand Levels in Non-survivor Traumatic Brain Injury Patients.

PURPOSE: Soluble Fas Ligand (sFasL) is one of the main ligands that activates the apoptosis extrinsic pathway. Higher expression of FasL in brain samples and higher cerebrospinal fluid FasL concentrations in traumatic brain injury (TBI) patients than in controls have been found. However, the potential association between blood sFasL concentrations and TBI mortality has not been reported. Therefore, the objective of this study was to determine whether that association exists. METHODS: We included patients with a severe isolated TBI, defined as < 9 points in Glasgow Coma Scale (GCS) and < 10 non-cranial aspects points in Injury Severity Score in this observational and prospective study performed in 5 Intensive Care Units. We measured serum sFasL concentrations on day 1 of TBI. RESULTS: We found that 30-day survivor (n = 59) in comparison to non-survivor patients (n = 24) had higher GCS (p = 0.001), lower age (p = 0.004), lower APACHE-II score (p < 0.001), lower intracranial pressure (ICP) (p = 0.01), lower computer tomography (CT) findings of high risk of death (p = 0.02) and lower serum sFasL concentrations (p < 0.001). The area under the curve for mortality prediction by serum sFasL levels was of 75% (95% CI = 63%-87%; p < 0.001). In Kaplan-Meier analysis was found that patients with serum sFasL levels > 29.2 pg/mL had a higher mortality rate (Hazard ratio = 6.2; 95% CI = 2.6-14.8; p < 0.001). Multiple logistic regression analysis found an association between serum sFasL levels and mortality after controlling for GCS, age and CT findings (OR = 1.055; 95% CI = 1.018-1.094; p = 0.004), and after controlling for APACHE-II, ICP and CT findings (OR = 1.048; 95% CI = 1.017-1.080; p = 0.002). CONCLUSIONS: The association between serum sFasL levels and 30-day mortality in TBI patients was the major novel finding of our study; however, future validation could be interesting to confirm those results.