Rengin Elsurer

Body shape index and mortality in hemodialysis patients

OBJECTIVE The relationship between various anthropometric parameters and mortality in hemodialysis (HD) patients is conflicting. Recently a new anthropometric parameter emerged, namely, body shape index (BSI). BSI is based on waist circumference (WC) but is independent of height, weight, and body mass index in predicting mortality in the general population. The aim of this study was to determine the relationship between BSI and mortality in HD patients. METHODS This retrospective study evaluated the demographic characteristics and anthropometric measures including BSI, laboratory parameters, and mortality data in HD patients in a single center. RESULTS There were 142 HD patients enrolled in the study. The median BSI was 0.0816. Because no normal value was defined for BSI, the patients were divided into two groups based on the median BSI: group 1 BSI < 0.0816 and group 2 BSI > 0.0816. During an average follow-up period of 40.1 ± 19.2 mo (range 12-88 mo), 36 (25.4%) patients had died. The Cox regression analysis of independence showed that increased age (hazard ratio [HR], 1.077, 95% confidence interval [CI],1.031-1.125; P = 0.001), presence of diabetes (HR, 2.855, 95% CI, 1.258-6.481; P = 0.012), hemoglobin (HR, 0.629, 95% CI, 0.452-0.875; P = 0.006), and albumin (HR, 0.442, 95% CI, 0.204-0.955; P = 0.038) were independently related with mortality. None of the anthropometric parameters including BSI were related with mortality. Kaplan-Meier analysis showed that there were no differences with respect to mortality among patients in group 1 and group 2 based on median BSI (P = 0.332, log-rank test). CONCLUSION In conclusion, BSI is not independently associated with mortality in HD patients.

The relationship between magnesium and ambulatory blood pressure, augmentation index, pulse wave velocity, total peripheral resistance, and cardiac output in essential hypertensive patients

Magnesium levels have been shown to be associated with elevated blood pressure (BP), endothelial dysfunction, insulin resistance, vascular calcification, inflammation, and atherosclerosis. It was also demonstrated that patients with hypertension have increased inflammation, insulin resistance, and endothelial dysfunction. However, the relationship between magnesium, ambulatory BPs, and central hemodynamic parameters were not evaluated extensively. Serum magnesium levels, ambulatory blood pressures, augmentation index (Aix), pulse wave velocity, total peripheral resistances, and cardiac output were measured for all patients. In total, 184 essential hypertension patients were enrolled. In univariate analysis, magnesium levels were correlated with hemoglobin (r = +0.155; P = .037), albumin (r = +0.180; P = .018), pulse pressure (daytime; r = -0.170; P = .021), pulse pressure (24-hour; r = -0.156; P = .035), Aix (daytime; r = -0.223; P = .002), Aix (nighttime; r = -0.169; P = .022), and Aix (24-hour; r = -0.247; P = .001). In regression analysis, magnesium levels were independently and conversely associated with daytime Aix (P < .0001), nighttime Aix (P = .019), and 24-hour Aix (P < .0001). We suggest that magnesium levels were associated with Aix but not with total peripheral resistances, pulse wave velocity, cardiac output, and central BPs. The unique mechanisms related with magnesium and Aix but not shared by other central parameters needs to be determined.

Urinary Sodium Excretion and Ambulatory Blood Pressure Findings in Patients With Hypertension

Use of ambulatory blood pressure (BP) monitoring (ABPM) allows for identification of dipping, nondipping, extreme dipping, and reverse dipping of BP. Using office BP and ABPM, hypertension subtypes can be identified: sustained normotension (SNT), white‐coat hypertension, masked hypertension, and sustained hypertension. The comparison of hemodynamic parameters and salt intake has not been investigated among these patient groups. Office BP, ABPM, augmentation index (AIx), pulse wave velocity (PWV), cardiac output (CO), and total peripheral resistance (TPR) were automatically measured. Estimation of salt intake was assessed by 24‐hour urinary sodium excretion. Urinary sodium excretion was not different among groups. AIx, PWV, CO, and TPR were lowest in patients with SNT. CO was lowest while AIx adjusted for a heart rate of 75 beats per minute, PWV, and TPR were highest in the extreme dipper group. No relationship was detected between hypertension subtypes and urinary sodium excretion.

The relationship between central hemodynamics, morning blood pressure surge, glycemic control and sodium intake in patients with type 2 diabetes and essential hypertension

AIMS The current study aimed to investigate the relationship between morning blood pressure surge (MBPS), hemodynamic parameters, glycemic control and 24-h urinary sodium excretion (USE) in patients with type 2 diabetes mellitus (T2DM). MATERIALS AND METHODS MBPS and central hemodynamic parameters were assessed from ambulatory blood pressure measurements. In addition to routine biochemistry, 24h urine collection was performed to measure protein, albumin and sodium excretion. RESULTS There were 146 (38%) patients with T2DM and 238 (72%) patients without T2DM (control group). Patients with T2DM had statistically higher MBPS compared with patients without T2DM (P<0.0001). In patients with T2DM, MBPS was correlated with HbA1c (rho=0.311, P<0.0001), 24h urinary sodium excretion (USE) (rho=0.292, P=0.004) and various hemodynamic parameters. Additionally, regression analysis showed that being male (P=0.006), the presence of coronary artery disease (P=0.023), HbA1c (P=0.012), and 24h USE (P=0.001) were independently related with log MBPS in T2DM patients. CONCLUSION This study demonstrated that T2DM was an independent risk factor for increased MBPS and MBPS was associated with central hemodynamic parameters. Additionally poor glycemic control and sodium intake were associated with worse MBPS in T2DM.

Does spironolactone ameliorate trastuzumab-induced cardiac toxicity?

The ErbB2 receptor is a proto-oncogene associated with a poor prognosis in breast cancer. Trastuzumab, a humanized anti-ErbB2 antibody currently in clinical use, has proven to be an essential tool in the immunotherapy of breast carcinoma. Additionally, ErbB2 is involved in the growth and survival pathway of adult cardiomyocytes which accounts for the trastuzumab-induced cardiotoxicity. Moreover, in metastatic breast cancer patients treated with trastuzumab, endomyocardial biopsy documented focal vacuolar changes, pleomorphic mitochondria, myocardial cell hypertrophy, and mild interstitial fibrosis on electron microscopy without accompanying light microscopic abnormalities, a finding consistent with a reversible pattern of cardiac injury. On the other hand, aldosterone and mineralocorticoid receptor (MR) researches have experienced a revival after the discovery that aldosterone and MR are not only involved in the electrolyte and volume balance but also in the pathophysiological processes of the reno-cardiovascular system. Aldosterone has both genomic and nongenotropic effects on epidermal growth factor receptor (EGFR) expression. Genomic effect induces genomic up-regulation of the EGFR protein expression via EGFR promoter, whereas nongenotropic effect leads to the EGFR transactivation resulting in persistent pathophysiological effects including formation of extracellular matrix and myocardial hypertrophy. Spironolactone, an aldosterone receptor antagonist, is known to ameliorate the cardiac damage. The underlying mechanism for the genomic interactions seem to be the stimulation of the EGFR promoter by aldosterone-bound MR, which then dose-dependently enhances the EGFR protein levels, which may be successively inhibited by spironolactone. By the light of these findings, we hypothesize that spironolactone may ameliorate trastuzumab-induced cardiotoxicity via inhibition of transactivation of the EGFR by aldosterone and reversing myocardial hypertrophy. This issue warrants further studies.

The relationship between weight, height and body mass index with hemodynamic parameters is not same in patients with and without chronic kidney disease

BackgroundAlthough anthropometric measurements are related with clinical outcomes; these relationships are not universal and differ in some disease states such as in chronic kidney disease (CKD). The current study was aimed to analyze the relationship between height, weight and BMI with hemodynamic and arterial stiffness parameters both in normal and CKD patients separately.MethodsThis cross-sectional study included 381 patients with (N 226) and without CKD (N 155) with hypertension. Routine laboratory and 24-h urine collection were performed. Augmentation index (Aix) which is the ratio of augmentation pressure to pulse pressure was calculated from the blood pressure waveform after adjusted heart rate at 75 [Aix@75 (%)]. Pulse wave velocity (PWV) is a simple measure of the time taken by the pressure wave to travel over a specific distance. Both [Aix@75 (%)] and PWV which are measures of arterial stiffness were measured by validated oscillometric methods using mobil-O-Graph device.ResultsIn patients without CKD, height is inversely correlated with [Aix@75 (%)]. Additionally, weight and BMI were positively associated with PWV in multivariate analysis. However, in patients with CKD, weight and BMI were inversely and independently related with PWV. In CKD patients, as weight and BMI increased stiffness parameters such as Aix@75 (%) and PWV decreased. While BMI and weight are positively associated with arterial stiffness in normal patients, this association is negative in patients with CKD.ConclusionIn conclusion, height, weight and BMI relationship with hemodynamic and arterial stiffness parameters differs in patients with and without CKD.

Association between serum bicarbonate and pH with depression, cognition and sleep quality in hemodialysis patients

Abstract Metabolic acidosis is a common feature in chronic renal failure patients, worsening progressively as renal function declines. There are conflicting data in hemodialysis (HD) patients with regard to acidosis, alkalosis and mortality. In HD patients, cognitive impairment, depression, sleep disorders and impaired quality of life are very common. Besides, these conditions are related with increased morbidity and mortality. However, no previous study investigated the relationship between pH, venous bicarbonate and anion gap with depression, sleep problems and cognitive function in HD patients. In this study we investigated these relationships. In total, 65 HD patients were included. The demographic parameters and laboratory parameters including bicarbonate, pH and anion gap was measured for all patients. Depressive symptoms, sleep quality and cognitive function, were measured by Beck depression inventory, The Pittsburgh Sleep Quality Index and by Mini Mental State Examination, respectively. We found that, sleep quality but not cognitive function or depression was independently related with venous pH and bicarbonate. Anion gap has no independent relationship with sleep quality, cognitive function and depression. In conclusion, metabolic acidosis and bicarbonate levels were independently related with sleep quality in HD patients. However, there was no association between metabolic acidosis and bicarbonate levels with cognitive function and depression.

Increased renal resistive index in type 2 diabetes: Clinical relevance, mechanisms and future directions

Type 2 diabetes is a global health challenge. In type 2 diabetes both microvascular (nephropathy, retinopathy, neuropathy) and macrovascular complications arise. In kidney, renal pathological changes leading to diabetic nephropathy are mainly secondary to atherosclerosis of the intra and extra renal arteries together with microangiopathy of the glomerular capillaries, afferent arterioles and efferent arterioles. Renal resistive index (RRI) is defined as a ratio of the difference between maximum and minimum (end-diastolic) flow velocity to maximum flow velocity derived from the Doppler measurements of main renal and intrarenal (segmental/interlobar) arteries. Renal resistive index is tightly related to renal arteriolosclerosis, and represents an integrated index of arterial compliance, pulsatility and downstream microvascular impedance. In meantime, growing suggest that RRI has also been closely related with atherosclerosis. Most studies performed in type 2 diabetes showed RRI is increased in type 2 diabetes. In this review, we summarize the data regarding RRI with regard to performed studies, pathogenesis and prognosis, especially focusing on type 2 diabetes (T2D). We also review the data regarding the development of metabolic syndrome (MetS) and RRI.

Central hemodynamics, vascular stiffness, and nocturia in patients with type 2 diabetes

Abstract Recently, studies have shown that the presence of nocturia may not be a benign condition and related with systemic illness and mortality. Elevated blood pressure (BP) was another factor related with nocturia. Type 2 diabetes mellitus (T2DM) is also associated with nocturia. It is now clear that, apart from peripheral BP, central hemodynamic parameters are important for cardiovascular prognosis. However, no previous study in the literature examined the relationship between nocturia and central hemodynamic parameters in patients with T2DM. The current study was designed to examine these relationships. Nocturia was defined as two or more voids per night. Central hemodynamic parameters were assessed from ambulatory BP measurements. In addition to routine biochemistry, 24-h urine collection was performed to measure protein, albumin, and sodium excretion. 158 patients (52.3%) had T2DM and 144 (47.7%) did not have T2DM (control group). The presence of T2DM was independently related with nocturia. Both in whole group and in T2DM patients, most of the hemodynamic parameters are higher in patients with nocturia compared to patients without nocturia. Among patients with T2DM, nocturia was associated with augmentation index and pulse wave velocity. In conclusion, central hemodynamic parameters and markers of vascular stiffness may be related with nocturia in patients with T2DM.