Reliability of electrocardiographic surrogates of left ventricular mass in patients with chronic kidney disease

Diagnosis of cardiovascular disease in patients with chronic kidney disease

Patients with chronic kidney disease (CKD) are at high risk of cardiovascular disease (CVD) and cardiovascular death. Identifying and monitoring cardiovascular complications and hypertension is important for managing patients with CKD or kidney failure and transplant recipients. Biomarkers of myocardial ischaemia, such as troponins and electrocardiography (ECG), have limited utility for diagnosing cardiac ischaemia in patients with advanced CKD. Dobutamine stress echocardiography, myocardial perfusion scintigraphy and dipyridamole stress testing can be used to detect coronary disease in these patients. Left ventricular hypertrophy and left ventricular dysfunction can be detected and monitored using various techniques with differing complexity and cost, including ECG, echocardiography, nuclear magnetic resonance, CT and myocardial scintigraphy. Atrial fibrillation and other major arrhythmias are common in all stages of CKD, and ambulatory heart rhythm monitoring enables precise time profiling of these disorders. Screening for cerebrovascular disease is only indicated in asymptomatic patients with autosomal dominant polycystic kidney disease. Standardized blood pressure is recommended for hypertension diagnosis and treatment monitoring and can be complemented by ambulatory blood pressure monitoring. Judicious use of these diagnostic techniques may assist clinicians in detecting the whole range of cardiovascular alterations in patients with CKD and enable timely treatment of CVD in this high-risk population.

[Left ventricular hypertrophy in hemodialysis patient: Prevalence, electrocardiographic, echocardiographic study and associated risk factors]

BACKGROUND

Left ventricular hypertrophy is the most prevalent cardiac abnormality in hemodialysis patients. The diagnosis of this abnormality is possible by electrocardiogram and/or echocardiography. Our study aimed to assess the prevalence of left ventricular hypertrophy in hemodialysis patients and the accuracy of different electrocardiographic criteria.

METHODS

This was a cross-sectional retrospective study including 60 hemodialysis patients between 2017 and 2018. A left ventricular mass index higher than 115g/m² and 95g/m² respectively in men and women defines echocardiographic left ventricular hypertrophy. We assessed left ventricular hypertrophy prevalence, sensitivity, specificity, and area under the receiver-operating characteristics (ROC) curve of fourteen different electrocardiographic criteria for identification of left ventricular hypertrophy.

RESULTS

This was a cohort of 60 patients composed of 27 men and 33 women with a mean age 52.6±15,8years. Hypertension was the most common cardiovascular risk factor (82 %). The prevalence of left ventricular hypertrophy at echography was 65 %. Prevalence of left ventricular hypertrophy at electrocardiographic varied across the different criteria ranging from 5 % (R wave in DI) to 32 % (Perugia score). The highest left ventricular hypertrophy prevalence at electrocardiographic was found with the five following criteria: Perugia score (32 %), Peguero-Lo Presti index (28 %), Sokolow-Lyon index, Cornell index, Framingham-adjusted Cornell voltage (17 %). Sensitivity was ranged from 5 % (R in DI, Gubner-Ungerleider index, and product) to 41 % (Perugia score). The specificity of most criteria was ≥90 % except for the Perugia score (85 %). The sensitivity, specificity, postitive and negative productive values and left ventricular hypertrophy prevalence using the five most accurate criteria combined were respectively 48, 90, 70.28, 77.85 and 33 %. Hypertension, duration of HD, arteriovenous fistula, interdialytic weight gain, systolic blood pressure, hemoglobin <9g/dL and hyperparathyroidism were significantly associated with left ventricular hypertrophy.

CONCLUSION

The prevalence of left ventricular hypertrophy detected by echocardiography was high. All electrocardiographic criteria had a low sensibility and a high specificity in the diagnostic of echocardiographic left ventricular hypertrophy. To improve the accuracy of electrocardiographic criteria, it is necessary to combine several electrocardiographic criteria and not often focused on a single classic electrocardiographic index.

N-terminal pro brain natriuretic peptide predicts both all-cause and cardiovascular disease mortality in Japanese hemodialysis patients

BACKGROUND

The association between N-terminal pro brain natriuretic peptide (NT-proBNP) level and long-term mortality in Japanese hemodialysis patients has not been fully assessed.

METHODS

This prospective, multicenter study included 1428 hemodialysis outpatients. Baseline NT-proBNP levels were measured at the first hemodialysis session of the week and participants were followed for 5 years. The areas under the curve were calculated from receiver operating characteristic curves. Groups determined by quartiles of baseline NT-proBNP level were assessed by the Kaplan-Meier method and log-rank test. The association between NT-proBNP level and mortality was assessed using multivariate Cox proportional hazards models.

RESULTS

During the 5-year follow-up, we observed 370 deaths and 256 censored cases. The areas under the curve of pre-hemodialysis NT-proBNP for all-cause mortality and cardiovascular disease mortality after 1 year were 0.75 and 0.78, respectively, and significantly greater than the areas under the curve at the 3- and 5-year follow-up. Cut-off values for all-cause mortality and cardiovascular disease mortality after 1 year were 4550 and 5467 ng/L, respectively (sensitivity: 82% and 81%; specificity: 59% and 64%). Kaplan-Meier survival analysis showed that the group with pre-hemodialysis NT-proBNP ≥ 8805 ng/L had increased all-cause mortality (P < 0.001) and cardiovascular disease mortality (P < 0.001). Finally, multivariate Cox analysis showed that NT-proBNP level was associated with all-cause mortality (P < 0.001) and cardiovascular disease mortality (P = 0.004) independently from other clinical parameters.

CONCLUSION

NT-proBNP is a useful marker to predict both all-cause and cardiovascular disease mortality in hemodialysis patients.

Additional prognostic value of electrocardiographic left ventricular hypertrophy in traditional cardiovascular risk assessments in chronic kidney disease

BACKGROUND

Left ventricular hypertrophy (LVH) is a common predictor of the cardiovascular prognosis in chronic kidney disease (CKD). However, whether or not electrocardiography-derived LVH (ECG-LVH) has prognostic value in patients with various degrees of CKD and improves the cardiovascular risk stratification based on traditional risk factors remains unclear.

METHODS

A total of 7206 participants at least 40 years of age who were free from cardiovascular events in a general population were followed for the incidence of cardiovascular events. CKD was confirmed by either the presence of a reduced estimated glomerular filtration rate (eGFR) (<60 ml/min per 1.73 m) or albuminuria, defined as a urinary albumin-to-creatinine ratio (UACR) of at least 30 mg/g Cr.

RESULTS

A total of 1886 (26.2%) had CKD, of which 1471 (78.0%) had a preserved eGFR (CKD stage 1-2). After an average 11.3 years of follow-up, the adjusted hazard ratio for the incidence of cardiovascular events significantly increased for ECG-LVH according to the Sokolow--Lyon voltage, Cornell voltage, or Cornell voltage product among participants with CKD (hazard ratio 1.47, P = 0.002), in contrast to those without CKD (hazard ratio 1.15, P = 0.210). The inclusion of any ECG-LVH parameters improved the accuracy of reclassification in any risk prediction model based on the eGFR, UACR, or Framingham 10-year risk score in the CKD participants (net reclassification improvement = 0.13-0.32, all P values <0.040).

CONCLUSION

In patients with CKD stage 1-5, ECG-LVH is useful for predicting the risk of future cardiovascular events and adds prognostic information to traditional cardiovascular risk assessments.

Multiplex proteomics for prediction of major cardiovascular events in type 2 diabetes

AIMS/HYPOTHESIS

Multiplex proteomics could improve understanding and risk prediction of major adverse cardiovascular events (MACE) in type 2 diabetes. This study assessed 80 cardiovascular and inflammatory proteins for biomarker discovery and prediction of MACE in type 2 diabetes.

METHODS

We combined data from six prospective epidemiological studies of 30-77-year-old individuals with type 2 diabetes in whom 80 circulating proteins were measured by proximity extension assay. Multivariable-adjusted Cox regression was used in a discovery/replication design to identify biomarkers for incident MACE. We used gradient-boosted machine learning and lasso regularised Cox regression in a random 75% training subsample to assess whether adding proteins to risk factors included in the Swedish National Diabetes Register risk model would improve the prediction of MACE in the separate 25% test subsample.

RESULTS

Of 1211 adults with type 2 diabetes (32% women), 211 experienced a MACE over a mean (±SD) of 6.4 ± 2.3 years. We replicated associations (<5% false discovery rate) between risk of MACE and eight proteins: matrix metalloproteinase (MMP)-12, IL-27 subunit α (IL-27a), kidney injury molecule (KIM)-1, fibroblast growth factor (FGF)-23, protein S100-A12, TNF receptor (TNFR)-1, TNFR-2 and TNF-related apoptosis-inducing ligand receptor (TRAIL-R)2. Addition of the 80-protein assay to established risk factors improved discrimination in the separate test sample from 0.686 (95% CI 0.682, 0.689) to 0.748 (95% CI 0.746, 0.751). A sparse model of 20 added proteins achieved a C statistic of 0.747 (95% CI 0.653, 0.842) in the test sample.

CONCLUSIONS/INTERPRETATION

We identified eight protein biomarkers, four of which are novel, for risk of MACE in community residents with type 2 diabetes, and found improved risk prediction by combining multiplex proteomics with an established risk model. Multiprotein arrays could be useful in identifying individuals with type 2 diabetes who are at highest risk of a cardiovascular event.

N-terminal pro brain natriuretic peptide as a cardiac biomarker in Japanese hemodialysis patients

Purpose:

This study examined the clinical significance of N-terminal pro brain natriuretic peptide level as a cardiac marker in Japanese hemodialysis patients.

Methods:

This was a multicenter cross-sectional study involving 1428 Japanese hemodialysis patients. Ultrasonic cardiography data at post-hemodialysis were obtained from 395 patients. We examined whether serum N-terminal pro brain natriuretic peptide levels were associated with cardiac parameters and assessed cut-off values and investigated factors associated with a reduced ratio of N-terminal pro brain natriuretic peptide levels pre- and post-hemodialysis.

Results:

Multivariate logistic regression analysis showed that pre- and post-hemodialysis N-terminal pro brain natriuretic peptide levels were associated with left ventricular hypertrophy on electrocardiogram (odds ratio: 3.10; p < 0.001 at pre-hemodialysis and odds ratio: 2.70; p < 0.001 at post-hemodialysis) and left ventricular hypertrophy on ultrasonic cardiography (odds ratio: 3.06; p < 0.001 at pre-hemodialysis and odds ratio: 3.15; p < 0.001 at post-hemodialysis). Post-N-terminal pro brain natriuretic peptide levels were also significantly associated with ejection fraction on urine chorionic gonadotrophin (ultrasonic cardiography; odds ratio: 35.83; p < 0.001). Receiver operating characteristic curves for predicting the presence of left ventricular hypertrophy on electrocardiogram and ultrasonic cardiography showed similar sensitivity (57.7%, 57.3% at pre-hemodialysis and 63.9%, 48.2% at post-hemodialysis) and specificity (66.5%, 72.9% at pre-hemodialysis and 59.2%, 81.9% at post-hemodialysis). Decreased ejection fraction on ultrasonic cardiography showed better sensitivity (78.6%) and specificity (88.7%). The N-terminal pro brain natriuretic peptide reduction ratio during a hemodialysis session correlated with Kt/V, membrane area, membrane type, modality, body weight gain ratio, treatment time, and ultrafiltration rate with multiple linear regression ( R: 0.53; p < 0.001 except for ultrafiltration rate ( p = 0.003)).

Conclusion:

Both pre- and post-hemodialysis N-terminal pro brain natriuretic peptide are associated with the presence of left ventricular hypertrophy in this population. The post-hemodialysis N-terminal pro brain natriuretic peptide level is a useful marker for systolic dysfunction.

Visceral Adipose Tissue and Leptin Hyperproduction Are Associated With Hypogonadism in Men With Chronic Kidney Disease

OBJECTIVE

Hypogonadism is a common endocrine disorder in men with chronic kidney disease (CKD), but its pathophysiology is poorly understood. We here explore the plausible contribution of abdominal adiposity and leptin hyperproduction to testosterone deficiency in this patient population.

DESIGN

Cross-sectional analysis with all men included the Malnutrition, Inflammation and Vascular Calcification cohort, which enrolled consecutive nondialyzed patients with CKD stages 3-5.

SUBJECTS

A total of 172 men with CKD stages 3-5 nondialysis (median age 61 [45-75] years, median glomerular filtration rate 24 [9-45] mL/min/1.73 m²). In them, serum levels of total testosterone, estrogen, sex hormone binding globulin, and leptin were quantified, together with visceral adipose tissue (VAT) by thoracic and abdominal CT scan.

INTERVENTION

None, observational study.

MAIN OUTCOME MEASURE

Total testosterone, hypogonadism.

RESULTS

The median level of total testosterone was 11.7 (7.3-18.4) nmol/L, with hypogonadism (<10 nmol/L) present in 52 (30%) patients. Testosterone-deficient patients presented with significantly higher body mass index, waist circumference, and VAT. An inverse correlation between testosterone and VAT (rho = -0.25, P = .001) or waist circumference (rho = -0.20, P = .008) was found, also after multivariate adjustment including sex hormone binding globulin and estrogen. Total testosterone was inversely correlated with serum leptin (rho = -0.22, P = .003), and the ratio of leptin/VAT, an index of leptin hyperproduction, was strongly and independently associated with the prevalence of hypogonadism in multivariable regression analyses.

CONCLUSION

Visceral adiposity independently associated with lower testosterone levels among men with CKD stage 3-5 nondialysis. The observed link between hyperleptinemia and hypogonadism is in line with previous evidence on direct effects of leptin on testosterone production.

The Stockholm CREAtinine Measurements (SCREAM) project: protocol overview and regional representativeness

BACKGROUND

We here describe the construction of the Stockholm CREAtinine Measurement (SCREAM) cohort and assess its coverage/representativeness of the Stockholm county in Sweden. SCREAM has the principal aims to estimate the burden and consequences of chronic kidney disease (CKD) and to identify inappropriate drug use (prescription of nephrotoxic, contraindicated or ill-dosed drugs).

METHODS

SCREAM is a repository of laboratory data of individuals, residing or accessing healthcare in the region of Stockholm, who underwent creatinine assessments between 2006-11. Laboratory tests were linked to administrative databases with complete information on socioeconomic status, demographic data, healthcare utilization, diagnoses, vital status and dispensed prescription medicines.

RESULTS

SCREAM identified 1 118 507 adult Stockholm citizens with available creatinine tests between 2006-11. This corresponded to 66% of the complete population in the region. Geographical coverage was uniform, ranging between 62 and 72% throughout its 26 municipalities. Population coverage was higher across older age strata (50% coverage for age range 18-44 years, >75% for 45-64 years and >90% coverage for ≥65 years). Of note, 97 and 98% of all individuals with a diagnosis of diabetes mellitus or cardiovascular disease, respectively, were captured by SCREAM. Further, 89% of all deaths registered in the period occurred in individuals with a creatinine test undertaken.

CONCLUSION

SCREAM represents the largest cohort to estimate the burden and healthcare implications of CKD in Sweden. The coverage and representativeness of the region of Stockholm was high and in accordance to both the commonness of creatinine assessment, and the medical indications for creatinine testing. The inclusion of individuals who sought medical care and had a creatinine test undertaken resulted in a slight over-representation of elderly and comorbid patients.

Epicardial fat accumulation, cardiometabolic profile and cardiovascular events in patients with stages 3-5 chronic kidney disease

BACKGROUND

It has been hypothesized that epicardial adipose tissue (EAT) exerts pathogenic effects on cardiac structures. We analysed the associations between EAT and both cardiovascular (CV) disease risk factors and CV events in patients with chronic kidney disease (CKD).

PATIENTS AND METHODS

We included 277 nondialysed patients [median age 61, interquartile range (IQR) 53-68 years; 63% men] with stages 3-5 CKD in this cross-sectional evaluation. EAT and abdominal visceral adipose tissue (VAT) were assessed by computed tomography. Patients were followed for median 32 (IQR 20-39) months, and the composite of fatal and nonfatal CV events was recorded.

RESULTS

With increasing EAT quartiles, patients were older, had higher glomerular filtration rate, body mass index, waist, VAT and coronary calcification, higher levels of haemoglobin, triglycerides, albumin, C-reactive protein and leptin and higher prevalence of left ventricular hypertrophy and myocardial ischaemia; total and high-density lipoprotein cholesterol, 25-hydroxy-vitamin D and 1, 25-dihydroxy-vitamin D progressively decreased. Associations between EAT and cardiac alterations were not independent of VAT. During follow-up, 58 CV events occurred. A 1-SD higher EAT volume was associated with an increased risk of CV events in crude [hazard ratio (HR) 1.41, 95% confidence interval (CI) (1.12-1.78) and adjusted (HR 1.55, 95% CI 1.21-1.99) Cox models. However, adding EAT to a standard CV disease risk prediction model did not result in a clinically relevant improvement in prediction.

CONCLUSION

Epicardial adipose tissue accumulation in patients with CKD increases the risk of CV events independent of general adiposity. This is consistent with the notion of a local pathogenic effect of EAT on the heart or heart vessels, or both. However, EAT adds negligible explanatory power to standard CV disease risk factors.

Cardiac imaging in patients with chronic kidney disease

Patients with chronic kidney disease (CKD) carry a high cardiovascular risk. In this patient group, cardiac structure and function are frequently abnormal and 74% of patients with CKD stage 5 have left ventricular hypertrophy (LVH) at the initiation of renal replacement therapy. Cardiac changes, such as LVH and impaired left ventricular systolic function, have been associated with an unfavourable prognosis. Despite the prevalence of underlying cardiac abnormalities, symptoms may not manifest in many patients. Fortunately, a range of available and emerging cardiac imaging tools may assist with diagnosing and stratifying the risk and severity of heart disease in patients with CKD. Moreover, many of these techniques provide a better understanding of the pathophysiology of cardiac abnormalities in patients with renal disease. Knowledge of the currently available cardiac imaging modalities might help nephrologists to choose the most appropriate investigative tool based on individual patient circumstances. This Review describes established and emerging cardiac imaging modalities in this context, and compares their use in CKD patients with their use in the general population.

Diagnostic validation and prognostic significance of the Malnutrition-Inflammation Score in nondialyzed chronic kidney disease patients

BACKGROUND

Malnutrition and inflammation are highly prevalent and intimately linked conditions in chronic kidney disease (CKD) patients that lead to a state of protein-energy wasting (PEW), the severity of which can be assessed by the Malnutrition-Inflammation Score (MIS). Here, we applied MIS and validated, for the first time, its ability to grade PEW and predict mortality in nondialyzed CKD patients.

METHODS

We cross-sectionally evaluated 300 CKD stages 3-5 patients [median age 61 (53-68) years; estimated glomerular filtration rate 18 (12-27) mL/min/1.73 m(2); 63% men] referred for the first time to our center. Patients were followed during a median 30 (18-37) months for all-cause mortality.

RESULTS

A worsening in MIS scale was associated with inflammatory biomarkers increase (i.e. alpha-1 acid glycoprotein, fibrinogen, ferritin and C-reactive protein) as well as a progressive deterioration in various MIS-independent indicators of nutritional status based on anthropometrics, dynamometry, urea kinetics and bioelectric impedance analysis. A structural equation model with two latent variables (assessing simultaneously malnutrition and inflammation factors) demonstrated good fit to the observed data. During a follow-up, 71 deaths were recorded; patients with higher MIS were at increased mortality risk in both crude and adjusted Cox models.

CONCLUSIONS

MIS appears to be a useful tool to assess PEW in nondialyzed CKD patients. In addition, MIS identified patients at increased mortality risk.