Risk factors for increased left ventricular hypertrophy in patients with chronic kidney disease

The Nephrologist's Role in the Collaborative Multi-Specialist Network Taking Care of Patients with Diabetes on Maintenance Hemodialysis: An Overview

Diabetes mellitus is the leading cause of renal failure in incident dialysis patients in several countries around the world. The quality of life for patients with diabetes in maintenance hemodialysis (HD) treatment is in general poor due to disease complications. Nephrologists have to cope with all these problems because of the “total care model” and strive to improve their patients’ outcome. In this review, an updated overview of the aspects the nephrologist must face in the management of these patients is reported. The conventional marker of glycemic control, hemoglobin A1c (HbA1c), is unreliable. HD itself may be responsible for dangerous hypoglycemic events. New methods of glucose control could be used even during dialysis, such as a continuous glucose monitoring (CGM) device. The pharmacological control of diabetes is another complex topic. Because of the risk of hypoglycemia, insulin and other medications used to treat diabetes may need dose adjustment. The new class of antidiabetic drugs dipeptidyl peptidase 4 (DPP-4) inhibitors can safely be used in non-insulin-dependent end-stage renal disease (ESRD) patients. Nephrologists should take care to improve the hemodynamic tolerance to HD treatment, frequently compromised by the high level of ultrafiltration needed to counter high interdialytic weight gain. Kidney and pancreas transplantation, in selected patients with diabetes, is the best therapy and is the only approach able to free patients from both dialysis and insulin therapy.

Association Between Indoxyl Sulfate and Dialysis Initiation and Cardiac Outcomes in Chronic Kidney Disease Patients

Introduction

Indoxyl sulfate, a protein-bound uremic toxin, has been reported as an atherosclerosis and fibrosis accelerator. This study aimed to determine whether serum indoxyl sulfate is associated with cardiac abnormalities, cardiovascular events, and renal progression to dialysis in patients with chronic kidney disease (CKD).

Methods

The prospective study enrolled 89 patients with CKD stage 3 to 5 patients. Serum biochemistry data and indoxyl sulfate were measured. All patients underwent echocardiographic examination. Global longitudinal strain (GLS) was calculated using two-dimensional speckle tracking. The clinical outcomes including cardiovascular event and dialysis initiation were recorded during a 2-year follow-up.

Results

Patients were divided into 2 groups based on the median value of serum indoxyl sulfate (low and high indoxyl sulfate groups). Kaplan–Meier analysis revealed that patients with higher indoxyl sulfate (≥6.124 mg/L) were significantly associated with renal progression to dialysis (p < 0.001). There was no significant difference in cardiovascular events between 2 groups (p = 0.082). In addition, serum indoxyl sulfate level was independently associated with GLS (r = 0.62; p = 0.01). The risk of cardiovascular events was significantly higher in patients with impaired GLS (>−16%) (p = 0.015).

Conclusion

Serum indoxyl sulfate level was a significant predictor for CKD progression to dialysis and was correlated with GLS, a speckle tracking echocardiography parameter representing early LV systolic dysfunction. Furthermore, GLS was associated with cardiovascular events in CKD patients. Serum indoxyl sulfate measurement may help to identify the high dialysis and cardiovascular risk CKD patients beyond traditional risk factors.

Determination of serum glycated albumin and high sensitivity C - reactive protein in the insight of cardiovascular complications in diabetic chronic kidney disease patients

Background

Left ventricular hypertrophy (LVH) has been proved as one among the cardiovascular complications and predominant in patients with CKD. In CKD patients, Glycated albumin (GA) express a superior marker of glycemic control than HbA1c. Nevertheless, the precision of GA for the prediction of cardiovascular diseases among the CKD population has been ineffectively reported. The present study looks at the part of GA, HbA1c in CKD to envisage vascular complications.

Materials and methods

One hundred and ninety-four patients were selected in the present study. The study has a control group (Group I, N: 52) and participants were divided into two groups based on vein diseases (Group II, N: 42; two vessels and group III, N: 100; triple vessel disease). Serum glycated albumin, hsCRP and other routine parameters were estimated in all the three groups. 2-dimensional echocardiography (2D Echo) has been done by a cardiologist to all the study patients for assessing ejection fraction and distinguish the sort of vessel diseases.

Results

Group I compared with group II and III shown there was a significant association among blood glucose, serum creatinine, HbA1c, mean blood glucose, GA, ejection fraction and hsCRP. Additionally, observed that increased levels of HbA1c, GA and creatinine inversely related to the left ventricle ejection fraction. Notwithstanding, GA and hsCRP predict precisely the left ventricle ejection fraction than different parameters.

Conclusion

GA alongside hsCRP might be appropriate markers for anticipating cardiovascular diseases particularly left ventricle hypertrophy in diabetic CKD population.

Reduced Estimated GFR and Cardiac Remodeling: A Population-Based Autopsy Study

RATIONALE & OBJECTIVE

Evidence suggests that cardiac remodeling, including left ventricular hypertrophy and myocardial fibrosis, develops with progression of kidney disease. Few studies have examined cardiac pathology across a range of estimated glomerular filtration rates (eGFRs), which was the objective of this investigation.

STUDY DESIGN

Population-based cross-sectional study of deceased patients undergoing autopsy.

SETTING & PARTICIPANTS

334 of 694 consecutive deceased patients undergoing autopsy with available cardiac tissue, with a prior health examination within 6 years and without a prior diagnosis of heart disease.

EXPOSURE

eGFR.

OUTCOMES

The thickness of the left ventricular wall, sizes of cardiac cells, and percentages of fibrosis, estimated from pathology examination of autopsy samples.

ANALYTICAL APPROACH

Generalized estimating equations.

RESULTS

Lower eGFRs were associated with greater left ventricular wall thickness. Deceased patients with eGFRs≥60, 45 to 59, 30 to 44, and <30mL/min/1.73m² had left ventricular wall thicknesses of 9.1, 9.5, 9.8, and 10.3mm, respectively (P for trend<0.05). Lower eGFRs were also significantly associated with greater mean values of cardiac cell size in the left ventricular wall after adjusting for confounders: 15.3, 16.1, 16.4, and 17.4μm for eGFRs≥60, 45 to 59, 30 to 44, and <30mL/min/1.73m² (P for trend<0.01). Patients with lower eGFRs had significantly higher multivariable-adjusted geometric mean values for fibrosis percentage in the left ventricular wall: 3.22%, 4.33%, 3.83%, and 6.14% for eGFRs≥60, 45 to 59, 30 to 44, and <30mL/min/1.73m² (P for trend<0.001). The negative association of eGFR with multivariable-adjusted mean values of cardiac cell width was stronger among patients with than those without anemia.

LIMITATIONS

Cross-sectional study with a high proportion of elderly patients, no available information for severity or duration of hypertension and other cardiovascular risk factors, no information for medication use.

CONCLUSIONS

These findings suggest that reduced eGFR is associated with cardiac hypertrophy and fibrosis of the left ventricle, cardiac cell enlargement, and cardiac fibrosis.

The reproducibility of cardiac magnetic resonance imaging measures of aortic stiffness and their relationship to cardiac structure in prevalent haemodialysis patients

BACKGROUND

Aortic stiffness is one of the earliest signs of cardiovascular disease (CVD) in patients with chronic kidney disease and an independent predictor of mortality. It is thought to drive left ventricular (LV) remodelling, an established biomarker for mortality. The relationship between direct and indirect measures of aortic stiffness and LV remodelling is not defined in dialysis patients, nor are the reproducibility of methods used to assess aortic stiffness using cardiac magnetic resonance (CMR) imaging.

METHODS

Using 3T CMR, we report the results of (i) the interstudy, interobserver and intra-observer reproducibility of ascending aortic distensibility (AAD), descending aortic distensibility (DAD) and aortic pulse wave velocity (aPWV) in 10 haemodialysis (HD) patients and (ii) the relationship between AAD, DAD and aPWV and LV mass index (LVMi) and LV remodelling in 70 HD patients.

RESULTS

Inter- and intra-observer variability of AAD, DAD and aPWV were excellent [intraclass correlation (ICC) > 0.9 for all]. Interstudy reproducibility of AAD was excellent {ICC 0.94 [95% confidence interval (CI) 0.78-0.99]}, but poor for DAD and aPWV [ICC 0.51 (-0.13-0.85) and 0.51 (-0.31-0.89)]. AAD, DAD and aPWV associated with LVMi on univariate analysis (β = -0.244, P = 0.04; β =-0.315, P < 0.001 and β = 0.242, P = 0.04, respectively). Only systolic blood pressure, serum phosphate and a history of CVD remained independent determinants of LVMi on multivariable linear regression.

CONCLUSIONS

AAD is the most reproducible CMR-derived measure of aortic stiffness in HD patients. CMR-derived measures of aortic stiffness were not independent determinants of LVMi in HD patients. Whether one should target blood pressure over aortic stiffness to mitigate cardiovascular risk still needs determination.

The regulation of NLRP3 inflammasome expression during the development of cardiac contractile dysfunction in chronic kidney disease

Chronic inflammation plays a crucial role in the long-term complications in patients with chronic kidney disease (CKD). This study aimed to assess the role of NLR pyrin domain-containing protein (NLRP3) inflammasome in cardiac contractile dysfunctions in CKD. The cardiac contractile function was evaluated and the expression of NLRP3 inflammasome and related cytokines in the heart was assessed in a murine sham-operated and 5/6 nephrectomy CKD model in vivo. In vitro, H9c2 cells were treated with uremic toxin indoxyl sulfate (IS), with or without NLRP3 inflammasome inhibition, which was achieved by using small interfering RNA (siRNA)-mediated knockdown of the NLRP3 gene. Moreover, the activation of nuclear factor κB (NF-κB) signaling and apoptosis marker levels were assessed in the IS-treated H9c2 cells. The results demonstrated that CKD can lead to the development of cardiac contractile dysfunction in vivo associated with the upregulation of NLRP3 inflammasome, IL-1β, IL-18, and contribute to the myocardial apoptosis. In vitro experiments showed the upregulation of inflammasome, IL-1β, and IL-18 levels, and cell apoptosis in the IS-treated H9c2 cells through the activation of NF-κB signaling pathway. The transfection of cells with si-NLRP3 was shown to alleviate IL-1β, IL-18, and cell apoptosis. Moreover, decreased cell viability induced by IS was shown to be attenuated by IL-1β or IL-18-neutralizing antibody. In summary, CKD can result in the development of cardiac contractile dysfunction associated with the upregulation of NLRP3 inflammasome/IL-1β/IL-18 axis induced by the uremic toxins.

A Low Geriatric Nutrition Risk Index Is Associated with Progression to Dialysis in Patients with Chronic Kidney Disease

Evaluating nutritional status is crucial to detecting malnutrition in patients with chronic kidney disease (CKD). The Geriatric Nutritional Risk Index (GNRI) has been associated with overall and cardiovascular mortality in the dialysis population. The aim of this study was to evaluate whether the GNRI is associated with progression to dialysis in patients with moderate to advanced CKD. We enrolled 496 patients with stage 3-5 CKD who had received echocardiographic examinations, and categorized them according to baseline GNRI values calculated using the serum albumin level and body weight. The renal end-point was defined as the commencement of dialysis. During follow-up (mean, 25.2 ± 12.5 months; range, 3.3-50.1 months), 106 (21.4%) of the patients progressed to dialysis. The GNRI was positively correlated with the left ventricular ejection fraction (LVEF) (r = 0.111, p = 0.014), and negatively correlated with the left ventricular mass index (r = -0.116, p = 0.001), left ventricular hypertrophy (r = -0.095, p = 0.035), and LVEF < 50% (r = -0.138, p = 0.002). In multivariable Cox analysis, a low GNRI, female sex, high systolic blood pressure, high fasting glucose, and low estimated glomerular filtration rate were independently associated with progression to dialysis. A low GNRI was independently associated with progression to dialysis in our study cohort. The GNRI may be useful in predicting the risk of adverse renal outcomes in patients with CKD stages 3-5. Additional studies are needed to explore whether an improvement in GNRI delays CKD progression.

Effect Modification of Chronic Kidney Disease on the Association of Circulating and Imaging Cardiac Biomarkers With Outcomes

Background

Cardiac troponin T and brain natriuretic peptide (BNP) are elevated in >50% of dialysis patients and are associated with poor outcomes. Few data investigated these associations in earlier chronic kidney disease (CKD).

Methods and Results

We studied whether CKD modified associations of elevated BNP, N‐terminal‐pro‐BNP, high‐sensitivity cardiac troponin T, coronary artery calcification, and left ventricular hypertrophy with all‐cause death and cardiovascular death/events in 3218 multiethnic individuals followed for 12.5 years, and whether biomarkers added prognostic information to traditional cardiovascular risk factors in CKD. Of the cohort, 279 (9%) had CKD. There were 296 deaths and 218 cardiovascular deaths/events. Of non‐CKD individuals, 7% died and 6% had cardiovascular death/event versus 32% and 30% of CKD participants, P<0.001 for both. The interaction between BNP and CKD on death was significant (P=0.01): the adjusted hazard ratio in CKD was 2.05, 95% CI (1.34, 3.14), but not significant in non‐CKD, 1.04 (0.76, 1.41). CKD modified the association of high‐sensitivity cardiac troponin T with cardiovascular death/event, adjusted hazard ratio 3.34 (1.56, 7.18) in CKD versus 1.65 (1.16, 2.35) in non‐CKD, interaction P=0.09. There was an interaction between N‐terminal‐pro‐BNP and CKD for death in those without prior cardiovascular disease. Addition of each biomarker to traditional risk factors improved risk prediction, except coronary artery calcification was not discriminatory for cardiovascular death/event in CKD.

Conclusions

Cardiac biomarkers, with the exception of coronary artery calcification, prognosticated outcomes in early‐stage CKD as well as, if not better than, in non‐CKD individuals, even after controlling for estimated glomerular filtration rate, and added to information obtained from traditional cardiovascular risk factors alone.

Gender-specific association of decreased estimated glomerular filtration rate and left vertical geometry in the general population from rural Northeast China

Background

Left ventricular hypertrophy (LVH) is common and associated with cardiovascular outcomes among patients with known chronic kidney disease (CKD). However, the link between decreased estimated glomerular filtration rate (eGFR) and left ventricular (LV) geometry remains poorly explored in general population. In this study, we examined the gender-specific association between eGFR and LVH in the general population from rural Northeast China.

Methods

This survey was conducted from July 2012 to August 2013. A total of 10907 participants (5,013 men and 5,894 women) from the rural Northeast China were randomly selected and examined. LV mass index (LVMI) was used to define LVH (LVMI > 46.7 g/m^2.7 in women; > 49.2 g/m^2.7 in men). LV geometry was defined as normal, or with concentric remodeling, eccentric or concentric hypertrophy, according to relative wall thickness (RWT) and LVMI. Mildly decreased eGFR was defined as eGFR ≥ 60 and < 90 ml/min/1.73 m², and moderate-severely decreased eGFR was defined as eGFR < 60 ml/min/1.73 m².

Results

As eGFR decreased, LVH showed a gradual increase in the entire study population. Multivariate analysis revealed a gender-specific relationship between eGFR and LV geometry. Only in men, mildly decreased eGFR was associated with concentric remodeling [odds ratio (OR): =1.58; 95% CI: 1.14–2.20; P < 0.01] and concentric LVH OR = 1.63; 95% CI: 1.15–2.31; P < 0.01). And only in men, moderate-severely decreased eGFR was a risk factor for concentric LVH (OR = 4.56; 95% CI: 2.14–9.73; P < 0.001) after adjusting for confounding factors.

Conclusions

These findings suggested that decreased eGFR was a risk factor for LV geometry in men, and a gender-specific difference should be taken into account in clinical practice.

Cardiac effect of vitamin D receptor modulators in uremic rats

Vitamin D receptor (VDR) modulators (VDRMs) are commonly used to control secondary hyperparathyroidism (SHPT) associated with chronic kidney disease, and are associated with beneficial outcomes in cardiovascular disease. In this study, we compared the cardiac effect of VS-105, a novel VDRM, with that of paricalcitol in 5/6 nephrectomized uremic rats. Male Sprague-Dawley rats were 5/6 nephrectomized, fed a standard diet for 4 weeks to establish uremia, and then treated (intraperitoneally, 3 times/week) with vehicle (propylene glycol), paricalcitol (0.025 and 0.15μg/kg), or VS-105 (0.05 and 0.3μg/kg) for 4 weeks. In uremic rats, neither VDRM (low and high doses) altered serum creatinine and phosphorus levels. Serum calcium was significantly higher with high dose paricalcitol compared to sham rats. PTH levels were significantly decreased with low dose paricalcitol and VS-105, and were further reduced in the high dose groups. Interestingly, serum FGF23 was significantly higher with high dose paricalcitol compared to sham rats, whereas VS-105 had no significant effect on FGF23 levels. Left ventricle (LV) weight and LV mass index determined by echocardiography were significantly suppressed in both high dose VDRM groups. This suppression was more evident with VS-105. Western blotting showed significant decreases in a fibrosis marker TGF-β1 in both high dose VDRM groups (vs. vehicle) and Masson trichrome staining showed significant decreases in cardiac fibrosis in these groups. These results suggest that VS-105 is less hypercalcemic than paricalcitol and has favorable effects on SHPT and cardiac parameters that are similar to those of paricalcitol in uremic rats. The cardioprotective effect is a noteworthy characteristic of VS-105.

Associations of Left Ventricular Hypertrophy and Geometry with Adverse Outcomes in Patients with CKD and Hypertension

BACKGROUND AND OBJECTIVES

Left ventricular hypertrophy (LVH) and abnormal left ventricular (LV) geometry predict adverse outcomes in the general and hypertensive populations, but findings in CKD are still inconclusive.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We enrolled 445 patients with hypertension and CKD stages 2-5 in two academic nephrology clinics in 1999-2003 who underwent both echocardiography and ambulatory BP monitoring. LVH (LV mass >100 g/m(2) [women] and >131 g/m(2) [men]) and relative wall thickness (RWT) were used to define LV geometry: no LVH and RWT≤0.45 (normal), no LVH and RWT>0.45 (remodeling), LVH and RWT≤0.45 (eccentric), and LVH and RWT>0.45 (concentric). We evaluated the prognostic role of LVH and LV geometry on cardiovascular (CV; composite of fatal and nonfatal events) and renal outcomes (composite of ESRD and all-cause death).

RESULTS

Age was 64.1±13.8 years old; 19% had diabetes, and 22% had CV disease. eGFR was 39.9±20.2 ml/min per 1.73 m(2). LVH was detected in 249 patients (56.0%); of these, 125 had concentric LVH, and 124 had eccentric pattern, whereas 71 patients had concentric remodeling. Age, women, anemia, and nocturnal hypertension were independently associated with both concentric and eccentric LVH, whereas diabetes and history of CV disease associated with eccentric LVH only, and CKD stages 4 and 5 associated with concentric LVH only. During follow-up (median, 5.9 years; range, 0.04-15.3), 188 renal deaths (112 ESRD) and 103 CV events (61 fatal) occurred. Using multivariable Cox analysis, concentric and eccentric LVH was associated with higher risk of CV outcomes (hazard ratio [HR], 2.59; 95% confidence interval [95% CI], 1.39 to 4.84 and HR, 2.79; 95% CI, 1.47 to 5.26, respectively). Similarly, greater risk of renal end point was detected in concentric (HR, 2.33; 95% CI, 1.44 to 3.80) and eccentric (HR, 2.30; 95% CI, 1.42 to 3.74) LVH. Sensitivity analysis using LVH and RWT separately showed that LVH but not RWT was associated with higher cardiorenal risk.

CONCLUSIONS

In patients with CKD, LVH is a strong predictor of the risk of poor CV and renal outcomes independent from LV geometry.

Association of Left Ventricular Hypertrophy With a Faster Rate of Renal Function Decline in Elderly Patients With Non-End-Stage Renal Disease

Background

Several studies have indicated that chronic kidney disease is independently associated with the presence of left ventricular hypertrophy (LVH). However, little clinical data are currently available regarding the detailed correlation between LVH and renal function in elderly patients with non–end‐stage renal disease.

Methods and Results

A total of 300 in‐ and outpatients (more than 60 years of age, non‐end‐stage renal disease), 251 with LVH and 49 without LVH, seen at Beijing Friendship Hospital from January 2000 to December 2010 were included in this retrospective study. One observation period of 12 months was used to detect rapid kidney function decline. The evaluations of cardiac structure and function were performed via echocardiography. The multivariable logistic analysis showed patients with LVH had a much higher risk of rapid kidney function decline than those without LVH. Additionally, the baseline left ventricular mass index was 140 (125–160) g/m² in the non–chronic kidney disease group, 152 (130–175) g/m² in the mild chronic kidney disease group (estimated glomerular filtration rate (eGFR)≥60 ml/min/1.73 m²), and 153 (133–183) g/m² in the severe chronic kidney disease group (eGFR<60 ml/min/1.73 m²), with a significant difference (P=0.009).

Conclusions

Our data demonstrate that a high rate of renal function decline contributes to pathological LVH in non–end‐stage renal disease elderly patients and that LVH is positively associated with renal function decline followed by an increased risk of rapid kidney function decline.

CB1 cannabinoid receptor antagonist attenuates left ventricular hypertrophy and Akt-mediated cardiac fibrosis in experimental uremia

Cannabinoid receptor type 1 (CB1R) plays an important role in the development of myocardial hypertrophy and fibrosis-2 pathological features of uremic cardiomyopathy. However, it remains unknown whether CB1R is involved in the pathogenesis of uremic cardiomyopathy. Here, we aimed to elucidate the role of CB1R in the development of uremic cardiomyopathy via modulation of Akt signalling. The heart size and myocardial fibrosis were evaluated by echocardiography and immunohistochemical staining, respectively, in 5/6 nephrectomy chronic kidney disease (CKD) mice treated with a CB1R antagonist. CB1R and fibrosis marker expression levels were determined by immunoblotting in H9c2 cells exposed to the uremic toxin indoxyl sulfate (IS), with an organic anion transporter 1 inhibitor or a CB1R antagonist or agonist. Akt phosphorylation was also assessed to examine the signaling pathways downstream of CB1R activation induced by IS in H9c2 cells. CKD mice exhibited marked left ventricular hypertrophy and myocardial fibrosis, which were reversed by treatment with the CB1R antagonist. CB1R, collagen I, transforming growth factor (TGF)-β, and α-smooth muscle actin (SMA) expression showed time- and dose-dependent upregulation in H9c2 cells treated with IS. The inhibition of CB1R by either CB1R antagonist or small interfering RNA-mediated knockdown attenuated the expression of collagen I, TGF-β, and α-SMA in IS-treated H9c2 cells, while Akt phosphorylation was enhanced by CB1R agonist and abrogated by CB1R antagonist in these cells. In summary, we conclude that CB1R blockade attenuates LVH and Akt-mediated cardiac fibrosis in a CKD mouse model. Uremic toxin IS stimulates the expression of CB1R and fibrotic markers and CB1R inhibition exerts anti-fibrotic effects via modulation of Akt signaling in H9c2 myofibroblasts. Therefore, the development of drugs targeting CB1R may have therapeutic potential in the treatment of uremic cardiomyopathy.

Cross-sectional analysis of serum calcium levels for associations with left ventricular hypertrophy in normocalcemia individuals with type 2 diabetes

Background

Left ventricular hypertrophy (LVH) is prevalent in patients with type 2 diabetes mellitus (T2DM). Recent studies show that an increase in albumin-adjusted serum calcium level is associated with an elevated risk of T2DM. We speculate that increased serum calcium levels in T2DM patients are related to LVH prevalence.

Methods

In this echocardiographic study, 833 normocalcemia and normophosphatemia patients with T2DM were enrolled. The associations between serum calcium and metabolic parameters, left ventricular mass index (LVMI), as well as the rate of LVH were examined using bivariate linear correlation, multivariate linear regression and logistic regression, respectively. The predictive performance of serum calcium for LVH was evaluated using the area under the receiver operating characteristic curve (AUC).

Results

Patients with LVH have significantly higher serum calcium than those without LVH. Serum calcium was positively associated with total cholesterol, triglycerides, low-density lipoprotein cholesterol, serum uric acid, HOMA-IR and fasting plasma glucose. Multivariate linear regression analysis demonstrated that serum calcium was independently associated with LVMI (p < 0.001). In comparison with patients in the lowest serum calcium quartile, the odds ratio (OR) for LVH in patients in the highest quartile was 2.909 (95% CI 1.792-4.720; p < 0.001). When serum calcium was analyzed as a continuous variable, per 1 mg/dl increase, the OR (95% CI) for LVH was [2.400 (1.552-3.713); p < 0.001]. Serum calcium can predict LVH (AUC = 0.617; 95% CI (0.577-0.656); p < 0.001).

Conclusions

Albumin-adjusted serum calcium is associated with an increased risk of LVH in patients with T2DM.

Utility of traditional circulating and imaging-based cardiac biomarkers in patients with predialysis CKD

Cardiac biomarkers, such as cardiac troponin T (cTnT), brain natriuretic peptide (BNP), and N-terminal-pro-BNP (NT-pro-BNP), are commonly used to diagnose acute coronary syndrome and congestive heart failure exacerbation in symptomatic patients. Levels of these biomarkers are frequently chronically elevated in asymptomatic patients with ESRD who are receiving maintenance dialysis. Other imaging biomarkers commonly encountered in nephrologists' clinical practice, such as coronary artery calcium measured by computed tomography, left ventricular hypertrophy, and carotid intima-media thickness, are also frequently abnormal in asymptomatic patients with ESRD. This article critically reviews the limited observational data on associations between cTnT, BNP, NT-pro-BNP, coronary artery calcium, left ventricular hypertrophy, and carotid intima-media thickness with cardiovascular events and death in non-dialysis-dependent patients with CKD. Although sufficient evidence suggests that these biomarkers may be used for prognostication, the diagnostic utility of cTnT, BNP, and NT-pro-BNP remain challenging in patients with CKD. Decreased renal clearance may affect the plasma levels of these biomarkers, and upper reference limits were originally derived in patients without CKD. Until better data are available, higher cutoffs, or a rise in level compared with previous values, have been proposed to help distinguish acute myocardial infarction from chronic elevations of cTnT in symptomatic patients with CKD. Additionally, it is not known whether these biomarkers are modifiable and amenable to interventions that could change hard clinical outcomes in patients with CKD not yet undergoing long-term dialysis.

Hyperuricemia and chronic kidney disease: an enigma yet to be solved

The role of uric acid (UA) on the pathogenesis and progression of chronic kidney disease (CKD) remains controversial. Experimental and clinical studies indicate that UA is associated with several risk factors of CKD including diabetes, hypertension, oxidative stress, and inflammation and hyperuricemia could be considered as a common dominator linking CKD and cardiovascular disease. Notably, the impact of serum UA levels on the survival of CKD, dialysis patients, and renal transplant recipients is also a matter of debate, as there are conflicting results from clinical studies. At present, there is no definite data whether UA is causal, compensatory, coincidental or it is only an epiphenomenon in these patients. In this article, we attempt to review and elucidate the dark side of this old molecule in CKD and renal transplantation.

Taming the chronic kidney disease epidemic: a global view of surveillance efforts

Chronic kidney disease is now recognized to be a worldwide problem associated with significant morbidity and mortality and there is a steep increase in the number of patients reaching end-stage renal disease. In many parts of the world, the disease affects younger people without diabetes or hypertension. The costs to family and society can be enormous. Early recognition of CKD may help prevent disease progression and the subsequent decline in health and longevity. Surveillance programs for early CKD detection are beginning to be implemented in a few countries. In this article, we will focus on the challenges and successes of these programs with the hope that their eventual and widespread use will reduce the complications, deaths, disabilities, and economic burdens associated with CKD worldwide.

Effects of insulin resistance on left ventricular hypertrophy in patients with CKD stage 1-3

BACKGROUND

Left ventricular hypertrophy (LVH) existed in patients with early stage chronic kidney disease (CKD). But whether insulin resistance (IR) exists in these patients and has some definite relationship with LVH, is unknown.

METHODS

Homeostatic model method was used for detecting homeostasis model assessment of insulin resistance (HOMA-IR) in 336 subjects including 286 patients with early stage CKD and 50 control subjects, and HOMA-IR and other clinical data in all subjects were obtained based on standard methods. Then, the relationship between LVH, IR and other relevant clinical data were analyzed.

RESULTS

IR and LVH existed in early stage CKD patients. The prevalence of LVH in patients with IR was significantly higher than those without, and patients with LVH had a higher prevalence of IR than those without. The patients with IR or LVH had lower levels of e-GFR, hemoglobin (Hb) and total cholesterol, while higher levels of blood urea nitrogen (BUN), serum creatinine (Scr), intact parathyroid hormone (iPTH), CRP and systolic blood pressure (SBP). HOMA-IR had positive correlations with left ventricular mass index (LVMI). HOMA-IR and LVMI had positive correlations with BUN, Scr, iPTH and CRP, but negative with e-GFR and Hb. Multiple linear stepwise regression analysis showed that e-GFR, FINS, Hb and SBP enter the regression equation. Binary unconditional logistic regression analysis indicated that the main risk factors for LVH were CKD and IR (P < 0.05, respectively).

CONCLUSION

Both IR and LVH existed in early stage CKD patients and were more severe with the development of CKD. IR had a significant correlation with LVH. Furthermore, decline of e-GFR, hypertension and anemia were also associated with both IR and LVH and may have some effects in the mechanism of IR on the development of LVH.

Decline of Renal Function and Progression of Left Ventricular Hypertrophy Are Independently Determined in Chronic Kidney Disease Stages 3-5

Invasive and noninvasive methods for evaluating the effects of hemodynamics on progression of left ventricular hypertrophy (LVH) in patients with chronic kidney disease (CKD) have been proposed. Central aortic pressure (CAP) has been reported to be the best among selected measures of hemodynamics for predicting LVH. However, there are few studies examining the relation between longitudinal changes in CAP and renal dysfunction in patients with CKD.

METHODS

Sixty-seven patients with CKD stages 3-5 (female/male ratio: 26/41, age: 61.5 ± 13.1 years) were followed for 5 years. Before and at the end of the 5-year period, CAP was recorded by an automated tonometric system (HEM-9000 AI; Omron Healthcare, Kyoto, Japan). Second systolic aortic blood pressure (SBP2) was employed as an index of CAP.

RESULTS

Throughout the study, systolic blood pressure (SBP) was well controlled. Renal function followed by estimated glomerular filtration rate (eGFR) gradually worsened as a whole. Ten patients had renal replacement therapy, 3 patients developed cardiovascular diseases and 2 patients were found to have a neoplasm during the 5-year observation period. SBP2 increased from 120 ± 19 to 125 ± 33 mm Hg and eGFR decreased from 38.2 ± 18.2 to 29.5 ± 16.3 ml/min/1.73 m(2); however, these differences did not achieve significance. The left ventricular mass (LVM) index significantly increased from 115.5 ± 10.5 to 131.2 ± 11.7 g/m(2) (p < 0.05). Although the changes in SBP2 and eGFR looked like a mirror image, there was no significant correlation between the two factors. Moreover, multivariate regression analysis did not reveal a close correlation between SBP2 and CKD progression. In contrast to the decline of renal function, the baseline value of SBP2 predicted an increase in the LVM index.

CONCLUSION

Worsening of renal dysfunction is not solely dependent on hemodynamics. Other factors might be involved in a complex manner.