Evaluation of E148Q and Concomitant AA Amyloidosis in Patients with Familial Mediterranean Fever.

The aim of the study was to compare the clinical phenotype of patients with familial Mediterranean fever (FMF)-related AA amyloidosis, according to the age of FMF diagnosis and E148Q genotype. Patients with biopsy-confirmed FMF-related AA amyloidosis were included in the study. Tel-Hashomer criteria were applied in the diagnosis of FMF. All patients had detailed baseline assessment of clinical features, renal functions, genetic testing, histopathological diagnosis of amyloidosis, and treatment received. Multiple comparisons were performed according to the age of diagnosis, disease phenotype, mutation, and mortality. Our study included 169 patients with a diagnosis of AA amyloidosis. There were 101 patients diagnosed with FMF < 18 years of age and 68 patients diagnosed who were ≥18 years of age. The three most common clinical manifestations were fever (84.6%), abdominal pain (71.6%), and arthritis (66.9%). The most common allele among FMF patients was M694V (60.6%), followed by E148Q (21.4%), and M680I (10.3%). The most frequent genotypes were M694V/M694V (45.0%), M694V/E148Q (14.8%), and E148Q/E148Q (11.2%) among 169 patients in our cohort. During the follow-up period, 15 patients (10 male, 5 female) died, of whom 14 had M694V homozygous genotype and one was homozygous for E148Q. Clinicians should be aware of patients with homozygous E148Q genotype for close monitoring and further evaluation. The possible relationship between E148Q and AA amyloidosis needs to be confirmed in other ethnicities.

Cardiovascular disease risk assessment in patients with familial Mediterranean fever related renal amyloidosis.

Chronic inflammation and proteinuria is a risk factor for cardiovascular disease (CVD) in patients with chronic kidney diseases and rheumatologic disorders. Our aim was to investigate the CVD events (CVDEs) and survival between the patients with FMF-related AA amyloidosis and glomerulonephropathies (GN) to define possible predictors for CVDEs. A prospective follow-up study with FMF-amyloidosis and glomerulonephropathy (GN) was performed and patients were followed for CVDEs. Flow-mediated dilatation (FMD), FGF-23, serum lipid, hsCRP levels, BMI and HOMA were assessed. A Cox regression analysis was performed to evaluate the risk factors for CVDEs. There were 107 patients in the FMF-amyloidosis group and 126 patients with GN group. Forty-seven CVDEs were observed during the 4.2-years follow up; all 28 patients in the FMF-amyloidosis group and 14/19 patients with GN developed CVDEs before the age of 40 (p = 0.002). CVD mortality was 2.8 times higher (95% CI 1.02-7.76) in patients with FMF-amyloidosis. Across both groups, FMD and FGF23 (p < 0.001) levels were independently associated with the risk of CVDEs. Patients with FMF-amyloidosis are at increased risk of early CVDEs with premature mortality age. FGF 23, FMD and hsCRP can stratify the risk of early CVD in patients with FMF-related AA amyloidosis.

The association of profilin-1 levels with survival in chronic kidney disease.

BACKGROUND: Profilin-1 is a ubiquitous, actin-binding protein that plays an important role in the regulation of actin polymerization and cytoskeleton remodelling and contributes to vascular dysfunction. We conducted this study to investigate the association of serum profilin-1 levels with fatal and nonfatal CVE in a cohort of patients with stage 1-5 CKD. MATERIALS AND METHODS: Serum concentrations of profilin-1 levels were determined by enzyme-linked immunosorbent assay. Endothelium-dependent vasodilatation (flow-mediated dilatation [FMD]) and endothelium-independent vasodilatation (nitroglycerine-mediated dilatation [NMD]) of the brachial artery were assessed noninvasively, using high-resolution ultrasound. RESULTS: Both fatal and nonfatal CVE were significantly higher in patients with high profilin-1 levels. Kaplan-Meier survival curves showed that patients with profilin-1 below the median value (114 pg/mL) had higher cumulative survival compared with patients who had profilin-1 levels above the median value (log-rank test, P < .001). CONCLUSIONS: This is the first study that demonstrates the serum profilin-1 is independently associated with endothelial dysfunction, cardiovascular events and survival in patients with CKD.

Blood pressure control in patients with hypertension: a retrospective cohort study.

RATIONALE, AIMS AND OBJECTIVES: Hypertension (HT) is prevalent in Turkey and even with pharmacological interventions HT control rates do not meet guideline recommendations. We aimed to estimate the proportion of hypertensive patients who achieved target blood pressure (BP) and seek to determine the predictors responsible for failure of to reach goals. METHODS: We conducted a retrospective cohort study involving patients with HT. A total of 437 patients were identified with a current diagnosis of HT at baseline. All available predictors for BP improvements were included in the multivariate linear regression model. RESULTS: Follow-up data on HT goal achievements was available for 276 (63.1%) participants. Only 18.1% of the patients at the baseline visit, and 48.6% at the follow-up visit achieved the overall SBP/DBP targets specified by the JNC-8 guideline. Significant differences were determined by baseline and 1st visit measurements of mean SBP/DBP levels (P < 0.001, P < 0.001, respectively). DM and baseline SBP were positively associated with SBP improvement (ß = 8.410, P = 0.003; ß = 0.692, P < 0.001, respectively), whereas being prescribing more HT medications and being older were negatively associated with improvement (ß = -7.968, P = 0.005; ß = -5.707, P = 0.037; respectively). DM, baseline DBP and HT duration were positively associated with DBP improvement (ß = 4.539, P = 0.012; ß = 0.702, P < 0.001; ß = 0.023, P = 0.012; respectively), whereas additional HT medications and GFR values were negatively associated with improvement (ß = -5.682, P = 0.002; ß = -0.098, P = 0.005; respectively). CONCLUSIONS: Although the progress in achieving in BP targets was encouraging, only half of patients had reached the HT goals. Adequate pharmacological approaches and comprehensive management strategies should be implemented in hypertensive patients.

Plasma endocan levels associate with inflammation, vascular abnormalities, cardiovascular events, and survival in chronic kidney disease.

Plasma endocan levels are elevated in a large number of diseases, and may reflect endothelial cell dysfunction. There are currently no data on endocan in patients with chronic kidney disease (CKD). Therefore, we measured plasma endocan in 251 patients with CKD (stage 1-5) and 60 control individuals. Plasma endocan concentrations correlated with estimated glomerular filtration rate (eGFR), different markers of inflammation (pentraxin 3 and high-sensitivity C-reactive protein), and vascular abnormalities (flow-mediated vasodilation (FMV) and carotid intima media thickness (CIMT)). All-cause mortality and cardiovascular events (CVE) were also analyzed with respect to plasma endocan. Patients with CKD showed significantly increased plasma endocan (4.7 [IQR 1.9-9.4] compared with controls [IQR 1.1-1.5] ng/ml), with values progressively higher across stages of CKD. On univariate analysis, plasma endocan concentrations correlated negatively with eGFR and FMV, but positively with both markers of inflammation and CIMT. However, on multivariate analysis only high-sensitivity C-reactive protein, FMV, and CIMT remained significantly associated with plasma endocan. On Cox survival analysis, endocan levels were associated with all-cause mortality and CVE in these patients. Thus, plasma endocan increases in the presence of decreasing eGFR and influences all-cause mortality and CVE in patients with CKD independent of traditional and nontraditional risk factors.

Endothelial function in patients with familial Mediterranean fever-related amyloidosis and association with cardiovascular events.

OBJECTIVES: Secondary amyloidosis is the most important complication of FMF and endothelial function is more severely impaired. Elevated asymmetric dimethyl arginine (ADMA) may mediate the excess cardiovascular disease (CVD) risk of this group. We aimed to compare endothelial function characteristics, including ADMA, in patients with FMF-related amyloidosis and primary glomerulopathies and to define risk factors for a CVD event. METHODS: We undertook a cross-sectional study with prospective follow-up including consecutive patients with FMF-related amyloidosis (n = 98) or other non-diabetic glomerulopathies (n = 102). All patients had nephrotic-range proteinuria and normal glomerular filtration rate. Flow-mediated dilatation (FMD) was assessed and ADMA levels, CRP and pentraxin 3 (PTX3) were determined. Patients were followed for cardiovascular events. RESULTS: Amyloidosis patients secondary to FMF showed higher levels of ADMA, CRP and PTX3 and lower FMD as compared with patients with other glomerulopathies. Cardiovascular events (n = 54) were registered during 3 years of follow-up. Increased ADMA levels and lower FMD were observed in patients with cardiovascular risk in both groups, but especially in individuals with amyloidosis. CONCLUSION: Patients with FMF-related amyloidosis have increased CVD event risk, probably related to the high ADMA levels, elevated inflammatory markers and decreased FMD measures observed in these patients.

Red cell distribution width is independently related to endothelial dysfunction in patients with chronic kidney disease.

BACKGROUND: Red cell distribution width (RDW) is a measure of erythrocyte size variability and has been shown as an independent predictor of mortality. The aim of this article was to evaluate the association of RDW with endothelial dysfunction in patients with chronic kidney disease (CKD). METHODS: Patients with 1 to 5 stages of CKD were included in the study. Endothelial function was assessed with flow-mediated dilatation (FMD). Estimated glomerular filtration rate (eGFR) and carotid intima media thickness (CIMT) were determined. Clinicodemographic characteristics, biochemical values, complete blood counts, ferritin, C-reactive protein (CRP) and cholesterol levels were recorded. Spearman's correlation was used to determine correlates of RDW. Multivariate linear regression model was used to assess independent associates of FMD. RESULTS: Overall, 367 patients with CKD 1 to 5 were included in the study. RDW showed a significant increase from stage 1 to stage 5 CKD. Median RDW was 13.5. Patients with RDW values higher than median had significantly lower hemoglobin, eGFR and FMD values and higher CIMT and CRP values compared with patients who had RDW values below median. RDW showed a significant positive correlation with the presence of diabetes mellitus, CIMT and CRP, whereas a significant negative correlation with eGFR, ferritin and FMD. Multivariate analysis showed independent predictors of FMD as RDW, presence of diabetes, hemoglobin, eGFR, CRP, and serum albumin. CONCLUSIONS: Multivariate regression model revealed RDW as a significant predictor of FMD independent of major confounding factors, such as diabetes, inflammation, anemia and kidney function in CKD.

Soluble TWEAK plasma levels increase after renal transplantation and associate with the improvement of endothelial function.

BACKGROUND: Soluble TWEAK (sTWEAK) and asymmetric dimethyl arginine (ADMA) concentrations have been associated with endothelial function in patients with chronic kidney disease (CKD). We tested the hypothesis that the improvement in endothelial function observed after renal transplantation is directly linked to the normalization of both sTWEAK and ADMA. MATERIALS AND METHODS: One hundred and seventy-five kidney transplant recipients (71% men; 31·6 ± 9·4 years) were studied immediately before and on the 180th day post-transplantation. At each visit, blood samples were taken to assess circulating levels of sTWEAK and ADMA. Brachial artery endothelium-dependent vasodilatation (FMD) assessments were also performed. RESULTS: Renal transplantation was followed by an improvement in FMD. This improvement was paralleled by an increase in sTWEAK and a reduction in ADMA after transplantation (P < 0·001 for all). Cross-sectionally, both molecules associated with FMD before as well as after transplantation (P < 0·001 for all). Longitudinally, the changes observed in sTWEAK (ß = 0·26, P < 0·001) and ADMA (ß = -0·44, P < 0·001) levels were independently associated with the improvement of FMD (r(2)  = 0·30). CONCLUSIONS: Renal transplantation is followed by an improvement of FMD that is independently associated with the normalization of both sTWEAK and ADMA concentrations. We identify two surrogate biomarkers of endothelial function with potential as therapeutic targets.

Vascular proteomics and the discovery process of clinical biomarkers: The case of TWEAK.

In the last years, big efforts are devoted to the search of novel biomarkers. Proteomic approaches in healthy and pathological samples may help us to discern differential protein expression patterns. These identified proteins include potential culprits in pathological pathways and/or clinical biomarkers to identify individuals at risk. However, extensively validation must be carried out before their implementation into the clinical practice. Biomarkers need to discriminate between health and disease, detect preclinical disease stages, have impact on survival prediction, and add predictive value beyond traditional risk factors and global risk algorithms. Now, we summarize the data of soluble tumor necrosis factor-like weak inducer of apoptosis (sTWEAK), a new cardiovascular biomarker identified by proteomic analysis. Decreased sTWEAK concentrations have been shown in patients with carotid atherosclerosis, coronary artery disease, congestive heart failure, peripheral artery disease, or chronic kidney disease (CKD). sTWEAK predicted adverse outcomes in patients with heart failure, myocardial infarction, and CKD. Finally, different drug regimens were able to modify sTWEAK plasma levels in patients with CKD. Although sTWEAK seems so far to fulfill the requisites in the development of a new biomarker, more large-scale studies are warranted to consolidate its usefulness.

Chitotriosidase activity predicts endothelial dysfunction in type-2 diabetes mellitus.

The enzyme chitotriosidase (ChT) is secreted by activated macrophages and play active role in human immune response. ChT activity is increased in atherosclerosis in association to the extent of the disease. We investigated the relevance of ChT to endothelial functions and insulin resistance in patients with T2DM. Forty newly diagnosed and untreated patients with T2DM (male 17; age 47.0 ± 6.2 years) and 50 healthy volunteers (male 21; age 50.2 ± 8.8 years) were enrolled. Plasma asymmetric dimethyl arginine (ADMA) levels were determined by ELISA. ChT activity was measured by the fluorescence method. Insulin resistance was calculated by the HOMA-IR formula. The patients had higher systolic blood pressures, HOMA-IR, ADMA levels, and ChT activities (P < 0.001 for all) and lower HDL cholesterol levels (P = 0.03) than the control group. The ChT activities of the total group were significantly correlated to the age (r = 0.031, p = 0.003), ADMA (r = 0.22, p = 0.04), and plasma glucose levels (r = 0.27, p = 0.01). ChT was the independent determinant of the plasma ADMA levels (r = 0.26, p = 0.02). The results of this study show that serum ChT activity is increased in patients with newly diagnosed, untreated, and uncomplicated patients with T2DM. The results also imply that increased ChT activity may be a predictor of endothelial dysfunction.

FGF-23 and vascular dysfunction in patients with stage 3 and 4 chronic kidney disease.

Studies in animals show that fibroblast growth factor (FGF)-23 interferes with vascular reactivity induced by the nitric oxide (NO) system. To investigate the relationship between circulating FGF-23 levels and the response of forearm blood flow to ischemia (flow-mediated vasodilatation, FMD) and nitroglycerin, we tested 183 patients with stage 3-4 chronic kidney disease (CKD). None of them had cardiovascular complications or were taking drugs interfering with vascular function. Patients with FGF-23 levels above the median had significantly lower glomerular filtration rate, FMD, and fetuin-A levels (an anti-inflammatory molecule and potent inhibitor of calcification). They also had higher proteinuria and phosphate levels when compared to patients whose FGF-23 levels were below the median. The response to nitroglycerin was not different between the two groups. Multiple regression analysis showed that the relationship between FGF-23 and FMD was only modestly sensitive to adjustment for classical risk factors, biomarkers of bone mineral metabolism, high-sensitivity C-reactive protein, and homeostatic model assessment index. Adjustment for asymmetrical dimethyl arginine (ADMA) weakened the strength of this link; however, it remained highly significant. There was no independent association between FGF-23 and nitroglycerin. Thus, attenuation of FMD by ADMA suggests that this endogenous inhibitor of NO synthase may, in part, mediate the vascular effects of FGF-23 in patients with CKD.

Hemoglobin is inversely related to flow-mediated dilatation in chronic kidney disease.

The microcirculation is regulated by oxygen gradients and by endothelial release of nitric oxide, which can react with hemoglobin to form S-nitroso derivatives. Here we induced flow-mediated dilatation of the brachial artery in response to ischemia in 141 non-diabetic patients with stage 3-4 chronic kidney disease who had no history of smoking, cardiovascular events or use of erythropoietin-based agents. Patients with hemoglobin concentrations above the cohort median of 11.6 g/dl were found to have significant reductions in flow-mediated dilatation compared to those below the median. This inverse relationship remained significant after adjustment for potential confounders, including insulin sensitivity, glomerular filtration rate, proteinuria, body mass index, serum urate, etiology of underlying renal disease, treatment with anti-hypertensive drugs, and traditional Framingham risk factors. Given that hemoglobin can act as an important nitric oxide carrier and buffer, our studies suggest that the mechanism by which hemoglobin influences the endothelium-dependent microcirculation requires its nitrosylation; however, more direct studies need to be performed.

Novel links between the long pentraxin 3, endothelial dysfunction, and albuminuria in early and advanced chronic kidney disease.

BACKGROUND AND OBJECTIVES: Albuminuria and inflammation predict cardiovascular events. Pentraxin 3, an inflammatory mediator produced by, among others, endothelial cells, may have a role in atherogenesis. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: In 207 Swedish patients with stage 5 chronic kidney disease and 79 Turkish patients with type 2 diabetes and proteinuria and normal renal function, whether serum pentraxin 3 levels are associated with albuminuria and endothelial dysfunction was studied. RESULTS: Patients with stage 5 chronic kidney disease and a high degree of albuminuria more often had diabetes and higher levels of pentraxin 3, vascular cellular adhesion molecule-1, and blood pressure. Moreover, pentraxin 3 was independently associated with 24-h urinary albumin excretion. In patients with type 2 diabetes, pentraxin 3 was significantly higher than in control subjects. Patients with type 2 diabetes and more proteinuria had higher pentraxin 3, C-reactive protein, glycosylated hemoglobin, insulin, and homeostasis model assessment index as well as lower flow-mediated dilation and serum albumin. Pentraxin 3 was positively correlated with C-reactive protein, homeostasis model assessment index, and carotid intima-media thickness and negatively with flow-mediated dilation. Pentraxin 3 and glomerular filtration rate were independently associated with 24-h urinary protein excretion. Only pentraxin 3 and proteinuria were significantly and independently associated with flow-mediated dilation. CONCLUSIONS: In two different renal cohorts, one of stage 5 chronic kidney disease and one of type 2 diabetes and normal renal function, pentraxin 3 was independently associated with proteinuria. Moreover, both pentraxin 3 and proteinuria were associated with endothelial dysfunction in patients with type 2 diabetes.

Effect of antihypertensive agents on plasma adiponectin levels in hypertensive patients with metabolic syndrome.

AIM: Plasma adiponectin levels are well associated with metabolic syndrome. However, the relationship between hypertension and plasma adiponectin levels is not clear. Also, there is not enough data about the effects of different antihypertensive regimens on plasma adiponectin levels. METHODS: Ninety-six hypertensive patients (48 male, 48 female) who fulfil the diagnostic criteria of metabolic syndrome were enrolled. Patients were treated for 3 months with metoprolol (n = 18, 100 mg/day), amlodipine (n = 20, 10 mg/day), doxazosin (n = 18, 4 mg/day), ramipril (n = 20, 5 mg/day) and valsartan (n = 20, 80 mg/day). Blood biochemistry and plasma adiponectin concentrations were measured both before and after the study. Insulin resistance was measured by homeostasis assessment index (HOMA). RESULTS: Plasma adiponectin levels were correlated with the total cholesterol (r = -0.244, P = 0.017), triglyceride (r = -0.306, P = 0.002), high-density lipoprotein-cholesterol (r = 0.286, P = 0.005), body mass index (r = -374, P < 0.001), systolic (r = -502, P < 0.001) and diastolic blood pressures (r = -235, P = 0.021). The independent predictors of plasma adiponectin levels were HOMA (beta = -0.199, P = 0.02), body mass index (beta = -0.313, P < 0.001) and systolic blood pressures (beta = -0.483, P < 0.001). Ramipril and valsartan increased the plasma adiponectin levels significantly higher than the other regimens (P < 0.05 for both) while metoprolol did not make a significant effect. CONCLUSION: According to the results, plasma adiponectin levels are associated with the arterial blood pressures, body fat content and the lipid parameters in hypertensive patients with metabolic syndrome. The effects of antihypertensive drugs on plasma adiponectin levels are parallel to their effects on blood pressures and insulin sensitivities. The different effects of several regimens on plasma adiponectin levels and insulin sensitivities may account for the diversity of the cardiovascular outcomes in patients with hypertension.