Sleep changes following statin therapy: a systematic review and meta-analysis of randomized placebo-controlled polysomnographic trials

INTRODUCTION

Statin use might be associated with an increased risk of sleep disturbances including insomnia, but the evidence regarding sleep changes following statin therapy has not been conclusive. Therefore we assessed the impact of statin therapy on sleep changes through a systematic review and meta-analysis of available randomized controlled trials (RCTs).

MATERIAL AND METHODS

We searched MEDLINE and SCOPUS up to October 1, 2014 to identify placebo-controlled RCTs investigating the effect of statin therapy on sleep changes. A meta-analysis was performed using either a fixed-effects or a random-effect model according to the I2 statistic. Effect size was expressed as weighted mean difference (WMD) and 95% confidence interval (CI).

RESULTS

Overall, the impact of statin therapy on polysomnography (PSG) indices of sleep was reported in 5 trials comprising 9 treatment arms. Overall, statin therapy had no significant effect on total sleep duration (WMD: -7.75 min, 95% CI: -18.98, 3.48, p = 0.176), sleep efficiency (WMD: 0.09%, 95% CI: -2.27, 2.46, p = 0.940), entries to stage I (WMD: 0.36, 95% CI: -0.91, 1.63, p = 0.580), or latency to stage I (WMD: -1.92 min, 95% CI: -4.74, 0.89, p = 0.181). In contrast, statin therapy significantly reduced wake time (WMD: -4.43 min, 95% CI: -7.77, -0.88, p = 0.014) and number of awakenings (WMD: -0.40, 95% CI: -0.46, -0.33, p < 0.001). Meta-regression did not suggest any correlation between changes in wake time and awakening episodes with duration of treatment and LDL-lowering effect of statins.

CONCLUSIONS

The results indicated that statins have no significant adverse effect on sleep duration and efficiency, entry to stage I, or latency to stage I sleep, but significantly reduce wake time and number of awakenings.

Impact of statin therapy on coronary plaque composition: a systematic review and meta-analysis of virtual histology intravascular ultrasound studies

BACKGROUND

Virtual histology intravascular ultrasound (VH-IVUS) imaging is an innovative tool for the morphological evaluation of coronary atherosclerosis. Evidence for the effects of statin therapy on VH-IVUS parameters have been inconclusive. Consequently, we performed a systematic review and meta-analysis to investigate the impact of statin therapy on plaque volume and its composition using VH-IVUS.

METHODS

The search included PubMed, Cochrane Library, Scopus and Embase (through 30 November 2014) to identify prospective studies investigating the effects of statin therapy on plaque volume and its composition using VH-IVUS.

RESULTS

We identified nine studies with 16 statin treatment arms and 830 participants. There was a significant effect of statin therapy in reducing plaque volume (standardized mean difference (SMD): -0.137, 95 % confidence interval (CI): -0.255, -0.019; P = 0.023), external elastic membrane volume (SMD: -0.097, 95 % CI: -0.183, -0.011; P = 0.027) but not lumen volume (SMD: -0.025, 95 % CI: -0.110, +0.061; P = 0.574). There was a significant reduction in fibrous plaque volume (SMD: -0.129, 95 % CI: -0.255, -0.003; P = 0.045) and an increase of dense calcium volume (SMD: +0.229, 95 % CI: +0.008, +0.450; P = 0.043), while changes in fibro-fatty (SMD: -0.247, 95 % CI: -0.592, +0.098; P = 0.16) and necrotic core (SMD: +0.011, 95 % CI: -0.144, +0.165; P = 0.892) tissue volumes were not statistically significant.

CONCLUSIONS

This meta-analysis indicates a significant effect of statin therapy on plaque and external elastic membrane volumes and fibrous and dense calcium volumes. There was no effect on lumen volume, fibro-fatty and necrotic tissue volumes.

Defining the role of trimetazidine in the treatment of cardiovascular disorders: some insights on its role in heart failure and peripheral artery disease

Trimetazidine is a cytoprotective drug whose cardiovascular effectiveness, especially in patients with stable ischemic heart disease, has been the source of much controversy in recent years; some have gone so far as to treat the medication as a ‘placebo drug’ whose new side effects, such as Parkinsonian symptoms, outweigh its benefits. This article is an attempt to present the recent key studies, including meta-analyses, on the use of trimetazidine in chronic heart failure, also in patients with diabetes mellitus and arrhythmia, as well as in peripheral artery disease. This paper also includes the most recent European Society of Cardiology guidelines, including those of 2013, on the use of trimetazidine in cardiovascular disease.

The multi-biomarker approach for heart failure in patients with hypertension

We assessed the predictive ability of selected biomarkers using N-terminal pro-brain natriuretic peptide (NT-proBNP) as the benchmark and tried to establish a multi-biomarker approach to heart failure (HF) in hypertensive patients. In 120 hypertensive patients with or without overt heart failure, the incremental predictive value of the following biomarkers was investigated: Collagen III N-terminal propeptide (PIIINP), cystatin C (CysC), lipocalin-2/NGAL, syndecan-4, tumor necrosis factor-α (TNF-α), interleukin 1 receptor type I (IL1R1), galectin-3, cardiotrophin-1 (CT-1), transforming growth factor β (TGF-β) and N-terminal pro-brain natriuretic peptide (NT-proBNP). The highest discriminative value for HF was observed for NT-proBNP (area under the receiver operating characteristic curve (AUC) = 0.873) and TGF-β (AUC = 0.878). On the basis of ROC curve analysis we found that CT-1 > 152 pg/mL, TGF-β < 7.7 ng/mL, syndecan > 2.3 ng/mL, NT-proBNP > 332.5 pg/mL, CysC > 1 mg/L and NGAL > 39.9 ng/mL were significant predictors of overt HF. There was only a small improvement in predictive ability of the multi-biomarker panel including the four biomarkers with the best performance in the detection of HF—NT-proBNP, TGF-β, CT-1, CysC—compared to the panel with NT-proBNP, TGF-β and CT-1 only. Biomarkers with different pathophysiological backgrounds (NT-proBNP, TGF-β, CT-1, CysC) give additive prognostic value for incident HF in hypertensive patients compared to NT-proBNP alone.

Sudden cardiac death in CKD patients

The risk of sudden cardiac death (SCD) is high in chronic kidney disease patients, and it increases with the progression of kidney function deterioration. The most common causes of SDC are the following: ventricular tachycardia, ventricular tachyarrhythmia, tachycardia torsade de pointes, sustained ventricular fibrillation and bradyarrhythmia. Dialysis influences cardiovascular system and results in hemodynamic disturbances as well as electrolyte shifts altering myocardial electrophysiology. Studies suggest that this procedure exerts both detrimental (poor volume control can exacerbate hypertension and left ventricle hypertrophy) and beneficial effects (associated with fluid removal and subsequent decrease in left ventricle stretch). Dialysis-related vulnerability to serious arrhythmias is the result of sudden shifts in fluid status and electrolytes, particularly potassium, which alter the physiological milieu. Also Ca(2+) ions, in which concentration alters during dialysis, are of key importance in the contraction of vascular smooth muscle cells and cardiac myocytes, thus exerting significant effects on hemodynamics. Due to the fact that SCD occurs with similar frequency in peritoneal dialysis and in hemodialysis patients, it seems that end-stage renal disease factors are more important than the specific ones associated with dialysis type. The results of randomized trials suggested that hemodialysis patients may not derive the same benefit of cardiovascular disease therapy including beta-blockers, calcium channel blockers and angiotensin-converting enzyme inhibitors as the general population with normal kidney function. Noninvasive tests used to stratify SCD risk in HD patients have poor positive value, and thus, combining tests including HRV, baroreceptor sensitivity and effectiveness index as well as its function indices and heart rate turbulence should be implemented. There are only few large randomized placebo-controlled trials assessing the influence of cardioprotective medications or implantable cardioverter defibrillator (ICD) implantation in dialysis patients on life quality and survival, and their results are sometimes contradictory. The decision concerning treatment and/or ICD implantation in this group of patients should be made on the basis of careful assessment of individual risk factors. Moreover, due to the high hazard of cardiovascular mortality including SCD in dialysis patients, physicians should concentrate on the early selection of high-risk patients, monitoring them and introduction of preventive measures.

Lack of efficacy of resveratrol on C-reactive protein and selected cardiovascular risk factors--Results from a systematic review and meta-analysis of randomized controlled trials

INTRODUCTION

Numerous studies have suggested that oral supplementation with resveratrol exerts cardioprotective effects, but evidence of the effects on C-reactive protein (CRP) plasma levels and other cardiovascular (CV) risk factors is inconclusive. Therefore, we performed a meta-analysis to evaluate the efficacy of resveratrol supplementation on plasma CRP concentrations and selected predictors of CV risk.

METHODS

The search included PUBMED, Cochrane Library, Web of Science, Scopus, and EMBASE (up to August 31, 2014) to identify RCTs investigating the effects of resveratrol supplementation on selected CV risk factors. Quantitative data synthesis was performed using a random-effects model, with weighted mean difference (WMD) and 95% confidence intervals (CI) as summary statistics.

RESULTS

Meta-analysis of data from 10 RCTs (11 treatment arms) did not support a significant effect of resveratrol supplementation in altering plasma CRP concentrations (WMD: -0.144 mg/L, 95% CI: -0.968-0.680, p = 0.731). Resveratrol supplementation was not found to alter plasma levels of total cholesterol (WMD: 1.49 mg/dL, 95% CI: -14.96-17.93, p = 0.859), low density lipoprotein cholesterol (WMD: -0.31 mg/dL, 95% CI: -9.57-8.95, p = 0.948), triglycerides (WMD: 2.67 mg/dL, 95% CI: -28.34-33.67, p = 0.866), and glucose (WMD: 1.28 mg/dL, 95% CI: -5.28-7.84, p = 0.703). It also slightly reduced high density lipoprotein cholesterol concentrations (WMD: -4.18 mg/dL, 95% CI: -6.54 to -1.82, p = 0.001). Likewise, no significant effect was observed on systolic (WMD: 0.82 mmHg, 95% CI: -8.86-10.50, p = 0.868) and diastolic blood pressure (WMD: 1.72 mm Hg, 95% CI: -6.29-9.73, p=0.674).

CONCLUSIONS

This meta-analysis of available RCTs does not suggest any benefit of resveratrol supplementation on CV risk factors. Larger, well-designed trials are necessary to confirm these results.

Lipids, blood pressure and kidney update 2014

This paper is an effort to review all the most important studies and guidelines in the topics of lipid, blood pressure and kidney published in 2014. Irrespective of advances, the options for improving simultaneous hypercholesterolemia and hypertension management (as well as its complication - chronic kidney disease) remain a problem. Recommending hypolidemic, hypotensive and kidney disease drugs to obtain therapy targets in cardiovascular, diabetic, elderly and kidney disease (=high risk) patients might strengthen risk factor control, improve compliance and the therapy efficacy, and in the consequence reduce the risk of cardiovascular events and mortality rate. That is why the authors have decided to summary and discuss the recent scientific achievements in the field of lipid, blood pressure and kidney.

Statin intolerance - an attempt at a unified definition. Position paper from an International Lipid Expert Panel

Statins are one of the most commonly prescribed drugs in clinical practice. They are usually well tolerated and effectively prevent cardiovascular events. Most adverse effects associated with statin therapy are muscle-related. The recent statement of the European Atherosclerosis Society (EAS) has focused on statin associated muscle symptoms (SAMS), and avoided the use of the term 'statin intolerance'. Although muscle syndromes are the most common adverse effects observed after statin therapy, excluding other side effects might underestimate the number of patients with statin intolerance, which might be observed in 10-15% of patients. In clinical practice, statin intolerance limits effective treatment of patients at risk of, or with, cardiovascular disease. Knowledge of the most common adverse effects of statin therapy that might cause statin intolerance and the clear definition of this phenomenon is crucial to effectively treat patients with lipid disorders. Therefore, the aim of this position paper was to suggest a unified definition of statin intolerance, and to complement the recent EAS statement on SAMS, where the pathophysiology, diagnosis and the management were comprehensively presented.

Should we use statins in all patients with chronic kidney disease without dialysis therapy? The current state of knowledge

PURPOSE

The aim of this article was to present the most important matters associated with dyslipidemia treatment in CKD patients. Moreover, the most important recommendations of the current (2013) KDIGO clinical practice guideline for lipid management in chronic kidney disease are presented.

METHODS

Authors looked through the most recent large clinical trials and meta-analyses and presented their results. We searched using the electronic databases [MEDLINE, EMBASE, Scopus, DARE]. Additionally, abstracts from national and international cardiovascular meetings were studied.

RESULTS

Analysis results suggest that statins exert beneficial effects on kidney since they considerably reduce 24 h urinary protein excretion and are associated with a rise in GFR. Beneficial effects of statins may be influenced by kidney disease stage, doses of medicine and treatment duration. Data suggest that statins are effective and safe for secondary prevention of CV events in individuals with mild CKD. Patients treated with statins had decreased frequency of major atherosclerotic events compared with placebo, reduced risk of CV mortality and deaths from all causes.

CONCLUSIONS

Meta-analyses results suggest that statins are associated with lipid lowering, cardiovascular and anti-proteinuric benefits in CKD patients. However, their effects on overall and cardiovascular mortality are much less obvious. Bearing in mind the advantageous effects and low risk of adverse effects, it seems that mild renal impairment should not exclude these patients from receiving a statin. However, because CKD patients in stages III-V are underrepresented in clinical trials, administration of statins to these patients who have not yet had a vascular event remains controversial.

Biomarkers and echocardiographic predictors of myocardial dysfunction in patients with hypertension

The study aimed to identify early echocardiographic and circulating biomarkers of heart failure (HF) in hypertensive patients with normal resting echocardiography. Echocardiography at rest and during exercise, and selected biomarkers were assessed in control group, dyspnea group, and HF group. On exercise dyspnea patients had lower early diastolic (E') and systolic (S') mitral annular velocity (12.8 ± 1.0 vs 14.9 ± 3.0 cm/sec and 9.3 ± 2.0 vs 10.9 ± 2.0 cm/sec, respectively), and higher E/E' ratio compared to control group (6.7 ± 1.0 vs 5.9 ± 1.0) (p < 0.05 for all comparisons). The level of N-terminal propeptide of procollagen type III (PIIINP) was significantly higher in dyspnea group than in controls (p = 0.01). Control and dyspnea patients had lower levels of cardiotrophin-1, cystatin C, syndecan-4, and N terminal-probrain natriuretic peptide than HF patients (all p ≤ 0.01). In multivariate analysis PIIINP (unadjusted odds ratio [OR] = 8.2, 95% confidence interval [Cl] 1.7-40.6; p = 0.001; adjusted OR = 8.7; 95%CI: 1.5-48.3; p = 0.001) and E/E' ratio on exercise (unadjusted OR = 1.8, 95%CI: 0.8-4.0; p = 0.033; adjusted OR = 2.0; 95%CI: 0.8-4.8; p = 0.012) were the only factors significantly associated with the presence of dyspnea. PIIINP is the first early biomarker for the HF development in patients with HA and normal resting echocardiography. Exertional echocardiography may indicate patients with incipient HF with preserved ejection fraction.

Evaluation of the effectiveness of methods of endoscopic treatment of bleeding from the duodenal mucosa

Bleeding from the upper gastrointestinal tract, despite the prevalence of endoscopic examinations and endoscopic methods of bleeding control, remains a significant problem. Available data indicate nondecreasing mortality of patients with active bleeding from the upper gastrointestinal tract although it is commonly known that such patients require fast endoscopic diagnosis and urgent treatment. Currently, the choice of method of endoscopic treatment of bleeding depends mostly on its availability and the decision of the physician performing the procedure.

AIM

The aim of the study was to evaluate the efficacy of different techniques of endoscopic hemostasis from the duodenum, mainly the comparison of monotherapy with the use of at least two techniques of endoscopic treatment of bleeding used simultaneously.

MATERIALS AND METHODS

This paper presents a retrospective analysis of medical records of 78 patients (27 women, 51 men; 33 of them were over 65 years), hospitalized in the Department of Nephrology, Hypertension and Family Medicine between 2009 and 2012. In all these patients, active bleeding from the duodenum was observed during endoscopy performed because of clinical signs of gastrointestinal bleeding, and the following methods of blood flow stemming were applied: injection with a solution of adrenaline alone or in combination with placement of clips.

RESULTS

The use of haemostatic clips alone or in a combination with injections of adrenaline around the bleeding site was demonstrated to be the most effective method of endoscopic control of bleeding from the duodenum. Injections of epinephrine around the bleeding site as monotherapy turned out to be the least effective method.

CONCLUSIONS

The most effective method of endoscopic control of bleeding from duodenal ulcers is the use of hemostatic clips alone or preceded by adrenaline injections, while the use of injections of adrenaline around the bleeding vessel was the least effective method.

Fibroblast growth factor 19-targeted therapies for the treatment of metabolic disease

INTRODUCTION

Fibroblast growth factors (FGFs) belong to the FGF superfamily with diverse biological functions, including proliferation, cellular differentiation, wound repair, angiogenesis and tumorigenesis. The ability to reduce liver fat content and concentrations of triglycerides, total cholesterol and plasma glucose, and to improve sensitivity and limit pro-lipogenic properties of insulin, makes FGF19 a promising therapeutic target for the treatment of metabolic syndrome. FGF19 regulates bile acid biosynthesis in the bile duct, glucose metabolism and vitamin D and phosphate homeostasis, raises the metabolic rate, reduces body weight, and ameliorates diabetes in mice. The therapeutic potential of FGF19 to treat metabolic disorders has been widely studied in animal models, but currently there are no reports concerning its use in humans.

AREAS COVERED

The following article highlights the metabolic effects and mechanism of action of FGF19. It also discusses the potential therapies that target FGF19.

EXPERT OPINION

FGF19 is emerging as a new target for the therapy of metabolic disorders, including diabetes. The results obtained from animal models are promising. However, there is still much to be done before the translation of these effects into practice will be possible.

Effects of coenzyme Q10 on statin-induced myopathy: a meta-analysis of randomized controlled trials

OBJECTIVE

To evaluate the efficacy of coenzyme Q10 (CoQ10) supplementation on statin-induced myopathy.

PARTICIPANTS AND METHODS

We searched the MEDLINE, Cochrane Library, Scopus, and EMBASE databases (November 1, 1987, to May 1, 2014) to identify randomized controlled trials investigating the impact of CoQ10 on muscle pain and plasma creatine kinase (CK) activity as 2 measures of statin-induced myalgia. Two independent reviewers extracted data on study characteristics, methods, and outcomes.

RESULTS

We included 6 studies with 302 patients receiving statin therapy: 5 studies with 226 participants evaluated the effect of CoQ10 supplementation on plasma CK activity, and 5 studies (4 used in the CK analysis and 1 other study) with 253 participants were included to assess the effect of CoQ10 supplementation on muscle pain. Compared with the control group, plasma CK activity was increased after CoQ10 supplementation, but this change was not significant (mean difference, 11.69 U/L [to convert to μkat/L, multiply by 0.0167]; 95% CI, -14.25 to 37.63 U/L; P=.38). Likewise, CoQ10 supplementation had no significant effect on muscle pain despite a trend toward a decrease (standardized mean difference, -0.53; 95% CI, -1.33 to 0.28; P=.20). No dose-effect association between changes in plasma CK activity (slope, -0.001; 95% CI, -0.004 to 0.001; P=.33) or in the indices of muscle pain (slope, 0.002; 95% CI, -0.005 to 0.010; P=.67) and administered doses of CoQ10 were observed.

CONCLUSION

The results of this meta-analysis of available randomized controlled trials do not suggest any significant benefit of CoQ10 supplementation in improving statin-induced myopathy. Larger, well-designed trials are necessary to confirm the findings from this meta-analysis.

Heart function disturbances in chronic kidney disease - echocardiographic indices

INTRODUCTION

In chronic kidney disease (CKD) patients left ventricular (LV) diastolic dysfunction occurs frequently and is associated with heart failure (HF) and higher mortality. Left ventricular systolic dysfunction is associated with coronary artery disease (CAD) and is a major determinant of prognosis. The aim of this study was to assess indices of LV diastolic dysfunction in CKD patients.

MATERIAL AND METHODS

Study included 118 CKD patients. All patients underwent transthoracic echocardiography. Diastolic function based on E and A, E/A ratio and pulmonary vein flow velocities as well as EF%, deceleration time, RA, LA volume were assessed. In dialysis patients examination was carried out before and after dialysis.

RESULTS

In CKD patients the stage of renal failure was associated with the significant increase in LV mass (268.0 ±47.6 CKD I/II vs. 432.7 ±122.4 CKD V/dialysis, p < 0.0001), systolic LV (37.3 ±4.5 vs. 51.2 ±8.9, p < 0.0001) and diastolic LV (CKD I-II 44.7 ±4.1 vs. CKD III 48.5 ±6.7 vs. CKD IV 47.1 ±5.6; p = 0.004) dimensions and in the size of the LA (40.4 ±2.0 vs. 41.9 ±2.7 vs. 42.3 ±3.2 vs. 44.8 ±3.1; p < 0.0001). The increase the E/E' ratio between groups of patients (6.7 ±1.5 vs. 8.9 ±2.4 vs. 11.5 ±4.0 vs. 13.5 ±5.0; p < 0.0001) was seen in this study. The reduction in deceleration time (247.2 ±34.5 in CKD I/II vs. 197.4 ±61.0 in CKD IV, p = 0.0005) along with the decrease in estimated glomerular filtration rate was also observed in this study.

CONCLUSIONS

Early identification of factors involved is necessary to prevent this devastating process. Many indexes of contractility are used and each of them has imperfections. It seems that TVI, E, E/A and E/E' are good instruments for the early detection of left ventricular hypertrophy and diastolic dysfunction.

Assessment of the relationship between lipid parameters and obesity indices in non-diabetic obese patients: a preliminary report

Background

The aim of this cross-sectional study was to examine the relationship between obesity and lipid markers.

Material/Methods

We divided 66 non-diabetic adult obese patients (mean age: 55.8±11.6 years) into 3 groups according to body mass index (BMI). All patients were measured for waist circumference (WC), hip circumference (HC), body mass index (BMI), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), body adiposity index (BAI), and visceral adiposity index (VAI). Serum levels of total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG) were determined, and lipid indices TC/HDL, LDL/HDL, and TG/HDL were also estimated.

Results

TC and LDL-C in Group III were lower than in Group I (5.0±1.0 vs. 6.0±1.0 mmol/L, and 2.9±0.9 vs. 3.8±1.2 mmol/L; p<0.05 for both). Negative correlations were found between: BMI and TC, LDL, and HDL (r=−0.291; r=−0.310, r=−0.240, respectively); and WC, WHR, VAI, and HDL (r=−0.371, r=−0.296, r=−0.376, respectively). Positive correlations were found between WC, WHR, and TG/HDL (r=0.279, r=0.244, respectively) and between VAI and: TC (r=0.327), TG (r=0.885), TC/HDL (r=0.618), LDL/HDL (r=0.480), and TG/HDL (r=0.927).

Conclusions

Obesity is associated with lipid disturbances, especially with HDL-C reduction, in obese non-diabetic patients. VAI is strongly related to lipid profile and thus may be the most valuable obesity index in obese patients with dyslipidemias.

Effects of polythiophene surface structure on adsorption and conformation of bovine serum albumin: a multivariate and multitechnique study

Protein interactions with surfaces of promising conducting polymers are critical for development of bioapplications. Surfaces of spin-cast and postbaked poly(3-alkylthiophenes), regiorandom P3BT, and regioregular RP3HT are examined prior to and after adsorption of model protein, bovine serum albumin, with time-of-flight secondary ion mass spectrometry, atomic force microscopy, and X-ray photoelectron spectroscopy. The multivariate method of principal component analysis applied to ToF-SIMS data maximizes information on subtle differences in surface chemistry: PCA reveals alkyl side chains and conjugated backbones, exposed for RP3HT and P3BT, respectively. Phase imaging AFM shows semicrystalline microstructure of RP3HT and amorphous morphology of P3BT films. A cellular-like pattern of proteins adsorbed on RP3HT develops with coverage to more uniform overlayer, observed always on P3BT. The amount of adsorbed protein, determined by XPS as a function of BSA concentration (up to 10 mg/mL), is ∼21% lower for RP3HT than P3BT (up to 1.1 mg/m(2)). Although PCA differentiates protein from polythiophene, relative protein surface composition evaluated from ToF-SIMS saturates rather than increases with amount of adsorbed BSA from XPS. This reflects ToF-SIMS sensitivity to outermost layer of proteins, enabling multivariate analysis of protein conformation or orientation. PCA distinguishes between amino acids characteristic for external regions of BSA adsorbed to P3BT and RP3HT. These amino acids are identified for P3BT and RP3HT as hydrophilic and hydrophobic, respectively, by relative hydrophobicity of amino acid side chains. Alternative identification with BSA domains fails, pointing to substrate-induced changes in conformation and degree of denaturation rather than orientation of adsorbed protein.

Markers of increased cardiovascular risk in patients with chronic kidney disease

BACKGROUND

Epidemiological studies have shown that chronic kidney disease (CKD) is an important risk factor for atherosclerosis and cardiovascular disease (CAD). The aim of the study was to determine markers of increased risk of CAD and to achieve a better understanding of agents implicated in the process of atherosclerosis in CKD patients.

METHODS

The study group consisted of a total of 139 patients with CKD while the control group comprised 45 healthy volunteers. Concentrations of osteoprotegerin, osteopontin, osteocalcin, matrix γ-carboxyglutamic acid (Gla) protein (MGP), fetuin A, matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9), tissue inhibitor of metalloproteinase-1 (TIMP-1), tissue inhibitor of metalloproteinase-2 (TIMP-2), ATP binding cassette transporter A1 (ABCA1), ATP binding cassette transporter G1 (ABCG1) and renalase were measured by the ELISA method.

RESULTS

We observed decreased levels of fetuin A (control vs. CKD group: 37.5 vs. 33.2 ng/ml, p = 0.018), and increased concentrations of osteocalcin (control vs. CKD group: 9.1 ± 6.0 vs. 13.6 ± 10.3 ng/ml, p = 0.05), MMP-2 (113.1 ± 75.0 vs. 166.0 ± 129.9 ng/ml, p = 0.045), TIMP-2 (22.1 ± 5.1 vs. 25.4 ± 7,0 ng/ml, p = 0.005) and renalase (251.0 ± 157 vs. 316.1 ± 155.3 ng/ml, p = 0.026). In patients with CKD (in comparison to control group), left ventricle ejection fraction: 53.0 ± 3,5% vs. 48.5%, p = 0.012) and calcification of the aortic valve (9.5% vs. 39.8%, p = 0.008) were observed more frequently.

CONCLUSIONS

Decreased levels of fetuin A and increased concentration of osteocalcin, renalase, MMP-2 and TIMP-2 suggest that these factors may be involved in the pathogenesis of CAD in patients with CKD. Significantly increased indices of cardiac hypertrophy and its dysfunction in patients with CKD are indicators of pathological mechanisms occurring in cardiovascular system in this group of patients.

Blood pressure levels and stroke: J-curve phenomenon?

The blood pressure J-curve discussion has been ongoing for more than 30 years, yet there are still questions in need of definitive answers. On one hand, existing antihypertensive therapy studies provide strong evidence for J-curve-shaped relationships between both diastolic and systolic blood pressure and primary outcomes in the general hypertensive patient population, as well as in high-risk populations, including subjects with coronary artery disease, diabetes mellitus, left ventricular hypertrophy, and the elderly. On the other hand, we have very limited data on the relationship between systolic and diastolic blood pressure and stroke prevention. Moreover, it seems that this outcome is more a case of “the lower the better.” Further large, well-designed studies are necessary in order to clarify this issue, especially as existing available studies are observational, and randomized trials either did not have or lost statistical power and were thus inconclusive.