Association of Frailty With Nutritional Status in Patients With Chronic Kidney Disease.

OBJECTIVES: Frailty is commonly observed in patients with chronic kidney disease (CKD) and is associated with adverse outcomes. Protein-energy wasting (PEW), a state of decreased body stores of protein and energy fuels, may be associated with frailty. However, few data are available on the possible association between frailty and PEW in CKD. METHODS: We examined the association between frailty and nutritional status assessed using anthropometric and body composition measurements, serum albumin, handgrip strength, the Malnutrition Inflammation Score (MIS), and dietary protein and calorie intake in a cross-sectional analysis of nondialysis patients with CKD stages 3-5. Body composition was assessed using multifrequency bioelectrical impedance. Frailty was defined as a Clinical Frailty Scale ≥4. We performed logistic regression with different nutrition assessment tools as the main predictors and age, sex, comorbidity, estimated glomerular filtration rate (eGFR), and hemoglobin as covariates. RESULTS: A total of 157 patients (93 men and 64 women; mean age 64 years; diabetes prevalence 38.9%) with CKD (eGFR 24.4 ± 13.4 mL/min/1.73 m2) were included. Overall, 29.3% of patients were frail. Patients with frailty were older and had a significantly higher fat tissue index and MIS but a significantly lower lean tissue index, eGFR, hemoglobin value, serum albumin value, handgrip strength value, and dietary protein intake. In multivariate logistic regression analyses, a higher body mass index category (odds ratio [OR], 1.54; 95% confidence interval [CI], 1.03-2.31), higher fat tissue index (OR, 1.15; 95% CI, 1.03-1.28), larger waist circumference (OR, 1.05; 95% CI, 1.01-1.09), reduced handgrip strength (OR, 2.70; 95% CI, 1.17-6.21), PEW defined by MIS ≥5 (OR, 3.49; 95% CI, 1.35-9.01), and dietary protein intake ≤0.8 g/kg/day (OR, 2.70; 95% CI, 1.18-6.19) were associated with higher odds of frailty. CONCLUSION: Frailty is associated with nutritional status in patients with CKD. A comprehensive nutrition assessment may allow the implementation of strategies to prevent or reduce frailty.

Dialysis Modality and Incident Stroke Among Patients With End-Stage Kidney Disease: A Registry-Based Cohort Study.

BACKGROUND: Patients with end-stage kidney disease undergoing dialysis are at significant risk of stroke. Whether dialysis modality is associated with cerebrovascular disease is unclear. This study compared the risk of incident stroke in patients undergoing peritoneal dialysis or hemodialysis. METHODS: Thirty-nine thousand five hundred forty-two patients without a history of stroke who initiated dialysis between January 1, 2010, and December 31, 2014 were retrospectively studied using Taiwan's National Health Insurance Research Database. We matched 3809 patients undergoing peritoneal dialysis (mean age 59±13 years; 46.5% women) and 11 427 patients undergoing hemodialysis (mean age 59±13 years; 47.3% women) by propensity score in a 1:3 ratio with follow-up through December 31, 2015. The primary outcome was incident acute ischemic stroke. Secondary outcomes included hemorrhagic stroke, acute coronary syndrome, and all-cause mortality. Cox proportional hazard models were conducted to determine hazard ratios of clinical outcomes according to the dialysis modality. RESULTS: During a median follow-up of 2.59 (interquartile range 1.50-3.93) years, acute ischemic stroke, hemorrhagic stroke, and acute coronary syndrome occurred in 783 (5.1%), 376 (2.5%), and 1350 (8.9%) patients, respectively. In a multivariable Cox model that accounted for the competing risk of death, acute ischemic stroke occurred more frequently in the peritoneal dialysis group than in the hemodialysis group (subdistribution hazard ratio, 1.32 [95% CI, 1.13-1.54]; P=0.0005). There were no significant treatment-related differences in the risk of hemorrhagic stroke (subdistribution hazard ratio, 0.89 [95% CI, 0.70-1.14]; P=0.3571) and acute coronary syndrome (subdistribution hazard ratio, 0.99 [95% CI, 0.88-1.12]; P=0.9080). Patients undergoing peritoneal dialysis were more likely to die from any cause than patients undergoing hemodialysis (adjusted hazard ratio, 1.24 [95% CI, 1.15-1.33]; P<0.0001). CONCLUSIONS: Peritoneal dialysis was associated with a significantly increased risk of acute ischemic stroke compared with hemodialysis. Further studies are needed to clarify whether more aggressive cerebrovascular preventive strategies might mitigate the excess risk for ischemic stroke among patients receiving peritoneal dialysis.

Association of diabetic retinopathy with risk of developing cardiovascular diseases in patients undergoing hemodialysis: A population-based cohort study.

BACKGROUND AND AIMS: While patients undergoing dialysis have substantially increased cardiovascular event rates compared with the general population, predicting individual risk remains difficult. Whether diabetic retinopathy (DR) is associated with cardiovascular diseases in this population is unclear. METHODS AND RESULTS: We conducted a nationwide cohort study of 27,686 incident hemodialysis patients with type 2 diabetes who were enrolled in Taiwan's National Health Insurance Research Database between January 1, 2010, and December 31, 2014, and had follow-up data until December 31, 2015. The primary outcome was a composite of macrovascular events, including acute coronary syndrome (ACS), acute ischemic stroke, and peripheral artery disease (PAD). A total of 10,537 (38.1%) patients had DR at baseline. We matched 9164 patients without DR (mean age, 63.7 years; 44.0% women) to 9164 patients with DR (mean age, 63.5 years; 43.8% women) by propensity score. During a median follow-up of 2.4 years, 5204 patients in the matched cohort experienced a primary outcome. The presence of DR was associated with a higher risk of a primary outcome (subdistribution hazard ratio [sHR] 1.07; 95% CI, 1.01-1.13), which reflected a higher risk of acute ischemic stroke (sHR 1.26; 95% CI, 1.14-1.39) and PAD (sHR 1.14; 95% CI, 1.05-1.25) but not ACS (sHR 0.99; 95% CI, 0.92-1.06). CONCLUSIONS: The presence of DR signifies an increased risk of acute ischemic stroke and PAD in hemodialysis patients with type 2 diabetes, independent of the known risk factors. These results highlight the need for more comprehensive cardiovascular assessment and management in hemodialysis patients with DR.

Associations of Glucometabolic Indices with Aortic Stiffness in Patients Undergoing Peritoneal Dialysis with and without Diabetes Mellitus.

Disruptions in glucose metabolism are frequently observed among patients undergoing peritoneal dialysis (PD) who utilize glucose-containing dialysis solutions. We aimed to investigate the relationship between glucometabolic indices, including fasting glucose, insulin resistance, advanced glycation end products (AGEs), PD-related glucose load, and icodextrin usage, and aortic stiffness in PD patients with and without diabetic mellitus (DM). This study involved 172 PD patients (mean age 58.3 ± 13.5 years), consisting of 110 patients without DM and 62 patients with DM. Aortic stiffness was assessed using the carotid-femoral pulse wave velocity (cfPWV). Impaired fasting glucose was defined as a fasting glucose level ≥ 100 mg/dL. Homeostatic model assessment for insulin resistance (HOMA-IR) scores, serum AGEs, dialysate glucose load, and icodextrin usage were assessed. Patients with DM exhibited the highest cfPWV (9.9 ± 1.9 m/s), followed by those with impaired fasting glucose (9.1 ± 1.4 m/s), whereas patients with normal fasting glucose had the lowest cfPWV (8.3 ± 1.3 m/s), which demonstrated a significant trend. In non-DM patients, impaired fasting glucose (ß = 0.52, 95% confidence interval [CI] = 0.01-1.03, p = 0.046), high HOMA-IR (ß = 0.60, 95% CI = 0.12-1.08, p = 0.015), and a high PD glucose load (ß = 0.58, 95% CI = 0.08-1.08, p = 0.023) were independently associated with increased cfPWV. In contrast, none of the glucometabolic factors contributed to differences in cfPWV in DM patients. In conclusion, among PD patients without DM, impaired fasting glucose, insulin resistance, and PD glucose load were closely associated with aortic stiffness.

Malnutrition is Associated with Increased Morbidity and Death in Dialysis Patients Undergoing Endovascular Therapy for Peripheral Artery Disease.

OBJECTIVE: Revascularisation for peripheral artery disease (PAD) is increasingly common in dialysis patients. Patients with PAD who have undergone revascularisation are at high risk of subsequent complications. Malnutrition is an important modifiable risk factor for dialysis patients, yet few data exist on the prognostic impact of malnutrition on post-procedure long term outcomes. The objective was to assess the prevalence and prognostic association of malnutrition using the Controlling Nutritional Status (CONUT) score in a prospective cohort of dialysis patients undergoing endovascular therapy (EVT) for PAD. METHODS: A total of 395 consecutive dialysis patients undergoing endovascular revascularisation for lower extremity PAD between 2005 and 2019 were examined for the primary outcome of all cause death. Secondary outcomes included major adverse limb events (MALEs), defined as acute limb ischaemia, major amputation, and clinically driven revascularisation; and major adverse cardiovascular events (MACEs). Nutritional status was assessed by CONUT score, a screening tool for malnutrition, incorporating albumin, cholesterol, and total lymphocyte count. RESULTS: According to the CONUT score, 40.8% of patients were moderately or severely malnourished. During a median follow up of 2.2 years, 218 (55.2%) patients died; 211 (53.4%) patients had MALEs, and MACEs occurred in 135 (34.2%) patients. Compared with normal nutritional status, severe malnutrition was associated with a significantly increased risk of all cause death (adjusted hazard ration [aHR] 4.83, 95% confidence interval [CI] 2.56 - 9.12) and MALEs (aHR 2.42, 95% CI 1.23 - 4.74) but not MACEs (aHR 1.81, 95% CI 0.74 - 4.40). Similar results were observed when the CONUT score was analysed as a continuous variable. CONCLUSION: Malnutrition is common in dialysis patients with PAD requiring endovascular therapy and is strongly associated with increased death and MALEs. Clinical trials are needed to evaluate whether nutritional interventions improve outcomes for dialysis patients after peripheral revascularisation.

Association of subjective global assessment of nutritional status with gut microbiota in hemodialysis patients: a case-control study.

BACKGROUND: Protein-energy wasting (PEW) is prevalent and associated with adverse outcomes in patients with chronic kidney disease (CKD). However, the pathogenesis of PEW in CKD patients has not been fully identified. The gut microbiota has been implicated in the regulation of host metabolism and energy balance. Therefore, we aimed to explore the association between nutritional status and the composition of the gut microbiota in hemodialysis patients. METHODS: Gut microbial diversity and taxonomy were examined in 88 hemodialysis patients with PEW (n = 22) and normal nutritional status (n = 66) who were matched 1:3 for age and sex. Nutritional status was assessed by using the 7-point subjective global assessment (SGA) score (1-3 = severe PEW; 4-5 = moderate PEW and 6-7 = normal nutrition). The gut microbiota was assessed by 16S ribosomal RNA gene sequencing. RESULTS: Patients with normal nutritional status had a significantly higher body mass index and physical activity and serum albumin levels, but significantly lower levels of inflammatory cytokines than patients with PEW. The most striking finding was that the α-diversity of the gut microbiota was significantly lower in patients with PEW. In a multivariate analysis, the SGA score was independently and positively associated with α-diversity (P = 0.049). Patients with or without PEW were different with respect to the principal coordinate analysis of ß-diversity. Notably, the relative abundance of Faecalibacterium prausnitzii, a butyrate-producing bacteria, was markedly reduced in patients with PEW. CONCLUSION: In hemodialysis patients, PEW assessed with the SGA was associated with gut dysbiosis.

Central obesity and incident atherosclerotic cardiovascular disease events in hemodialysis patients.

BACKGROUND AND AIMS: Waist circumference and waist-hip ratio have been shown to predict atherosclerotic cardiovascular disease (ASCVD) in the general population, but the association is less clear in patients with CKD. Both anthropometric measures of central obesity are surrogates for underlying fat and are prone to measurement error. The aim of this study was to investigate the association between central obesity determined by dual-energy X-ray -absorptiometry (DXA) and ASCVD among patients undergoing maintenance hemodialysis. METHODS AND RESULTS: We prospectively analyzed a cohort of 166 prevalent hemodialysis patients (60 ± 12 years of age). Total adiposity (total fat mass) and central adiposity (android and gynoid fat mass) were assessed by using DXA. Central obesity was defined as a sex-specific android to gynoid fat mass ratio (A/G ratio) above the median. The main outcome measure was incident ASCVD events. Patients with central obesity had significantly higher BMI, total fat mass, high-sensitivity C-reactive protein, and triglycerides but significantly lower high-density lipoprotein cholesterol than patients without central obesity. During a median follow-up of 4.3 years, 40 patients had an incident ASCVD event. Patients with central obesity did not display a significantly higher risk of ASCVD in multivariate Cox regression analysis (hazard ratio 1.03, 95% confidence interval 0.54-1.97). A/G ratio, when examined as a continuous variable, was not an independent predictor of ASCVD in either sex. CONCLUSIONS: Hemodialysis patients with central obesity, as measured by the A/G ratio, had less favorable plasma lipid profiles and higher levels of inflammation but not an increased risk of ASCVD.

Body composition is associated with clinical outcomes in patients with non-dialysis-dependent chronic kidney disease.

An inverse relationship between body mass index (BMI) and mortality (the obesity paradox) has been found in patients with non-dialysis-dependent chronic kidney disease (CKD). However, it is unclear whether increased muscle mass or body fat confers the survival advantage. To resolve this we investigated the impact of body makeup on a composite outcome of death or cardiovascular events in a prospective cohort of 326 patients with stage 3-5 CKD not yet on dialysis. Lean mass and body fat were determined using the Body Composition Monitor, a multifrequency bioimpedance spectroscopy device, and were expressed as the lean tissue or fat tissue index, respectively. Patients were stratified as High (above median) or Low (below median) BMI, High or Low lean tissue index, or as High or Low fat tissue index. During a median follow-up of 4.6 years, there were 40 deaths and 68 cardiovascular events. In Cox proportional hazards models, a High lean tissue index, but not High BMI or High fat tissue index, predicted a lower risk of both the composite or its component outcomes (reference: below median). When patients were further stratified into four distinct body composition groups based on both the lean and fat tissue index, only the High lean/fat tissue index group had a significantly lower risk of the composite outcome (hazard ratio 0.36, 95% confidence interval 0.14-0.87; reference: Low lean/fat tissue index group). Thus, the lean tissue index can provide better risk prediction than the BMI alone in non-dialysis-dependent patients with CKD. The High lean/fat tissue index appears to be associated with best outcomes. An optimal body composition for improving the prognosis of CKD needs to be determined.

Serum Indoxyl Sulfate Associates with Postangioplasty Thrombosis of Dialysis Grafts.

Hemodialysis vascular accesses are prone to recurrent stenosis and thrombosis after endovascular interventions.In vitro data suggest that indoxyl sulfate, a protein-bound uremic toxin, may induce vascular dysfunction and thrombosis. However, there is no clinical evidence regarding the role of indoxyl sulfate in hemodialysis vascular access. From January 2010 to June 2013, we prospectively enrolled patients undergoing angioplasty for dialysis access dysfunction. Patients were stratified into tertiles by baseline serum indoxyl sulfate levels. Study participants received clinical follow-up at 6-month intervals until June 2014. Primary end points were restenosis, thrombosis, and failure of vascular access. Median follow-up duration was 32 months. Of the 306 patients enrolled, 262 (86%) had symptomatic restenosis, 153 (50%) had access thrombosis, and 25 (8%) had access failure. In patients with graft access, free indoxyl sulfate tertiles showed a negative association with thrombosis-free patency (thrombosis-free patency rates of 54%, 38%, and 26% for low, middle, and high tertiles, respectively;P=0.001). Patients with graft thrombosis had higher free and total indoxyl sulfate levels. Using multivariate Cox regression analysis, graft thrombosis was independently predicted by absolute levels of free indoxyl sulfate (hazard ratio=1.14;P=0.01) and free indoxyl sulfate tertiles (high versus low, hazard ratio=2.41;P=0.001). Results of this study provide translational evidence that serum indoxyl sulfate is a novel risk factor for dialysis graft thrombosis after endovascular interventions.

Indoxyl sulfate suppresses endothelial progenitor cell-mediated neovascularization.

Patients with chronic kidney disease have an increased prevalence of peripheral arterial disease. Endothelial progenitor cells (EPC) are pivotal in neovascularization, but their role in mediating peripheral arterial disease in chronic kidney disease is not fully known. Here we studied the impact of indoxyl sulfate, a protein-bound uremic toxin, on EPC function in response to tissue ischemia or cell hypoxia in mice that underwent subtotal nephrectomy or sham operation. At 16 weeks, unilateral hindlimb ischemia was induced in all. Four weeks later, subtotal nephrectomy mice had significantly increased plasma levels of indoxyl sulfate, reduced reperfusion, decreased EPC mobilization, and impaired neovascularization in ischemic hindlimbs compared with control mice. Treatment with AST-120, an oral adsorbent of uremic toxins, reversed these changes. Ischemia-induced protein expression including phospho-eNOS, phospho-STAT3, interleukin-10, and VEGF were significantly decreased in ischemic hindlimbs of subtotal nephrectomy mice versus control mice; all effects were reversed by AST-120. Subtotal nephrectomy mice fed a diet with indole for 12 weeks resulted in impaired neovascularization in ischemic hindlimbs; also reversed by AST-120. In cultured human EPCs, VEGF expression was increased in hypoxia through HIF-1α and interleukin-10/STAT3 signaling; effects suppressed by pretreatment with indoxyl sulfate. Moreover, indoxyl sulfate markedly attenuated hypoxia-induced EPC migration and tube formation. Thus, indoxyl sulfate may be a therapeutic target for EPC-rescue of impaired neovascularization in patients with chronic kidney disease and peripheral arterial disease.

Periodontal Disease and Risks of Kidney Function Decline and Mortality in Older People: A Community-Based Cohort Study.

BACKGROUND: The association between periodontal disease and chronic kidney disease in older people is controversial, and evidence for a causal link between kidney function decline and subsequent mortality risk is limited. STUDY DESIGN: Longitudinal, observational, community-based cohort study. SETTING & PARTICIPANTS: Participants were citizens 65 years or older who received the Taipei City Government-sponsored Annual Elderly Health Examination Program during 2005 to 2010, including dental status assessment and biochemical examinations. PREDICTORS: Participants with periodontal disease defined by the World Health Organization Community Periodontal Index of Treatment Need criteria. OUTCOMES: All-cause and cardiovascular mortality and estimated glomerular filtration rate (eGFR) decline ≥ 30% over 2 years. RESULTS: Of 100,263 study participants, 13,749 (13.7%) had periodontal disease. In a mean follow-up of 3.8 years, all-cause and cardiovascular mortality rates in those with periodontal disease (11.5% and 2.6%, respectively) were higher compared with those without periodontal disease (6.7% and 1.6%, respectively). After adjustment for demographic characteristics, comorbid conditions, and biochemistry data, adjusted HRs for all-cause and cardiovascular mortality were 1.34 (95% CI, 1.26-1.42) and 1.25 (95% CI, 1.13-1.41), respectively. The frequency of eGFR decline ≥ 30% over 1-, 2-, and 3-years' follow-up in those with periodontal disease was 1.8%, 3.7%, and 4.0%, respectively. In a logistic regression model, adjusted ORs of the detrimental effect of periodontal disease on 30% eGFR decline in participants over 1-, 2-, or 3-years' follow-up were 1.03 (95% CI, 0.85-1.25), 1.62 (95% CI, 1.41-1.87), and 1.59 (95% CI, 1.37-1.86), respectively. In subgroup analyses according to age, sex, and comorbid conditions, risks for eGFR decline and mortality remained consistent. LIMITATIONS: Results may not be generalizable to other non-Asian ethnic populations. CONCLUSIONS: The results indicate that periodontal disease is a risk factor for all-cause and cardiovascular mortality and eGFR decline ≥ 30% over 2 to 3 years in older people.

Iron supplementation associates with low mortality in pre-dialyzed advanced chronic kidney disease patients receiving erythropoiesis-stimulating agents: a nationwide database analysis.

BACKGROUND: A risk/benefit analysis of iron supplementation in pre-dialysis advanced chronic kidney disease (CKD) patients has not been conducted. We aim to assess the effectiveness and the safety of iron supplementation in patients with CKD Stage 5 who have not yet received dialysis (CKD 5 ND). METHODS: A prospective cohort study was conducted based on the Taiwan National Health Insurance Research Database. From 1 January 2000 to 30 June 2009, we enrolled 31 971 adult patients who had a serum creatinine >6 mg/dL and a haematocrit <28% and who were treated with erythropoiesis-stimulating agents (ESAs). All patients were further divided into two groups with or without iron supplementation within 90 days after starting ESA therapy. Patient follow-up took place until dialysis, death before initiation of dialysis or 31 December 2009. The primary outcomes were death before initiating dialysis, hospitalization before death or long-term dialysis. RESULTS: After propensity score matching, the patients who received iron supplementation were associated with a lower risk of all-cause death [hazard ratio (HR), 0.85; 95% confidence interval (CI), 0.80-0.90] compared with non-users. The survival benefit of iron use was consistent across the majority of dosage groups, except for those who were treated with monthly IV iron >200 mg. Moreover, compared with the non-users, the iron users were associated with a lower risk of hospitalizations (HR, 0.97; 95% CI, 0.94-0.99) but with a higher risk of faster progression to end-stage renal disease (HR, 1.05; 95% CI, 1.01-1.08). CONCLUSIONS: Iron supplementation is associated with 15% risk reduction in death among CKD 5 ND patients who received ESA treatment. Randomized studies are needed to validate this association.

Iron sucrose accelerates early atherogenesis by increasing superoxide production and upregulating adhesion molecules in CKD.

High-dose intravenous iron supplementation is associated with adverse cardiovascular outcomes in patients with CKD, but the underlying mechanism is unknown. Our study investigated the causative role of iron sucrose in leukocyte-endothelium interactions, an index of early atherogenesis, and subsequent atherosclerosis in the mouse remnant kidney model. We found that expression levels of intracellular cell adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) and adhesion of U937 cells increased in iron-treated human aortic endothelial cells through upregulated NADPH oxidase (NOx) and NF-κB signaling. We then measured mononuclear-endothelial adhesion and atherosclerotic lesions of the proximal aorta in male C57BL/6 mice with subtotal nephrectomy, male apolipoprotein E-deficient (ApoE(-/-)) mice with uninephrectomy, and sham-operated mice subjected to saline or parenteral iron loading. Iron sucrose significantly increased tissue superoxide production, expression of tissue cell adhesion molecules, and endothelial adhesiveness in mice with subtotal nephrectomy. Moreover, iron sucrose exacerbated atherosclerosis in the aorta of ApoE(-/-) mice with uninephrectomy. In patients with CKD, intravenous iron sucrose increased circulating mononuclear superoxide production, expression of soluble adhesion molecules, and mononuclear-endothelial adhesion compared with healthy subjects or untreated patients. In summary, iron sucrose aggravated endothelial dysfunction through NOx/NF-κB/CAM signaling, increased mononuclear-endothelial adhesion, and exacerbated atherosclerosis in mice with remnant kidneys. These results suggest a novel causative role for therapeutic iron in cardiovascular complications in patients with CKD.

Length polymorphism in heme oxygenase-1 and risk of CKD among patients with coronary artery disease.

The length polymorphism of guanosine thymidine dinucleotide repeats in the heme oxygenase-1 gene promoter is associated with cardiovascular events and mortality in high-risk populations. Experimental data suggest that heme oxygenase-1 protects against kidney disease. However, the association between this polymorphism and long-term risk of CKD in high-risk patients is unknown. We analyzed the allelic frequencies of guanosine thymidine dinucleotide repeats in the heme oxygenase-1 gene promoter in 386 patients with coronary artery disease recruited from January 1999 to July 2001 and followed until August 31, 2012. The S allele represents short repeats (<27), and the L allele represents long repeats (≥27). The primary renal end points consisted of sustained serum creatinine doubling and/or ESRD requiring long-term RRT. The secondary end points were major adverse cardiovascular events and mortality. At the end of study, the adjusted hazard ratios (95% confidence intervals) for each L allele in the additive model were 1.99 (1.27 to 3.14; P=0.003) for the renal end points, 1.70 (1.27 to 2.27; P<0.001) for major adverse cardiovascular events, and 1.36 (1.04 to 1.79; P=0.03) for mortality. With cardiac events as time-dependent covariates, the adjusted hazard ratio for each L allele in the additive model was 1.91 (1.20 to 3.06; P=0.01) for the renal end points. In conclusion, a greater number of guanosine thymidine dinucleotide repeats in the heme oxygenase-1 gene promoter is associated with higher risk for CKD, cardiovascular events, and mortality among patients with coronary artery disease.

ESA and iron therapy in chronic kidney disease: a balance between patient safety and hemoglobin target.

Optimal treatment algorithms for erythropoiesis-stimulating agent (ESA) and iron therapy in anemic CKD patients are lacking. Kuragano et al. evaluated hemodialysis patients over two years and report increased mortality risk and/or adverse events in those with high serum ferritin levels and high ferritin fluctuations, and an increase in adverse events in iron users. Clinical practice should avoid disproportionately high ESA or iron doses to achieve hemoglobin targets, particularly in those with significant comorbidity or ESA resistance.

Volume overload correlates with cardiovascular risk factors in patients with chronic kidney disease.

Volume overload is a predictor of mortality in dialysis patients. However, the fluid status of patients with chronic kidney disease (CKD) but not yet on dialysis has not been accurately characterized. We used the Body Composition Monitor, a multifrequency bioimpedance device, to measure the level of overhydration in CKD patients, focusing on the association between overhydration and cardiovascular disease risk factors. Overhydration was the difference between the amount of extracellular water measured by the Body Composition Monitor and the amount of water predicted under healthy euvolemic conditions. Volume overload was defined as an overhydration value at and above the 90th percentile for the normal population. Of the 338 patients with stages 3-5 CKD, only 48% were euvolemic. Patients with volume overload were found to use significantly more antihypertensive medications and diuretics but had higher systolic blood pressures and an increased arterial stiffness than patients without volume overload. In a multivariate analysis, male sex, diabetes, pre-existing cardiovascular disease, systolic blood pressure, serum albumin, TNF-α, and proteinuria were independently all associated with overhydration. Thus, volume overload is strongly associated with both traditional and novel risk factors for cardiovascular disease. Bioimpedance devices may aid in clinical assessment by helping to identify a high-risk group with volume overload among stages 3-5 CKD patients.

Anaemia management in patients with chronic kidney disease: Taiwan practice guidelines.

The introduction of erythropoiesis-stimulating agents (ESAs) markedly improved the lives of many anaemic patients with chronic kidney disease (CKD). In Taiwan, the strategy of management of anaemia in patients with CKD was different from many other parts of the world. In 1996, the National Health Insurance Administration of Taiwan applied a more restrictive reimbursement criteria for ESA use in patients with CKD. ESA is to be initiated when non-dialysis CKD patients have a serum creatinine >6 mg/dL and a hematocrit <28% to maintain a hematocrit level not exceeding 30%. The maximal dose of epoetin-α or ß was 20 000 U per month. The target haemoglobin range and dose limitation for ESAs were the same for dialysis CKD patients. Thus, long before randomized controlled trials showing an increased risk for cardiovascular events at nearly normal haemoglobin concentrations and higher ESA doses in CKD, nephrologists in Taiwan had avoided the use of disproportionately high dosages of ESAs to achieve a haemoglobin level of 10-11 g/dL. Moreover, intravenous iron supplementation was encouraged earlier in Taiwan in 1996, when we reached consensus on the diagnostic criteria for iron deficiency (serum ferritin <300 ng/mL and/or transferrin saturation <30%). The experience of CKD anaemia management in Taiwan demonstrated that a reasonable haemoglobin target can be achieved by using the lowest possible ESA dose and intravenous iron supplementation.

Erythropoiesis-stimulating agents in chronic kidney disease: what have we learned in 25 years?

Since the pioneering studies by Eschbach et al in 1987, erythropoiesis-stimulating agents (ESAs) have become the mainstay of anemia therapy in chronic kidney disease (CKD) patients. The introduction of ESAs 25 years ago markedly improved the lives of many patients with CKD, who until then had severe, often transfusion-dependent anemia. However, randomized controlled trials demonstrate an increased risk for cardiovascular events such as stroke, thrombosis, and death at nearly normal hemoglobin concentrations and higher ESA doses in CKD. By contrast, kidney transplant recipients may represent a unique population of CKD patients who may benefit from ESA therapy. This review discusses potential mechanisms involving the erythropoietic and nonerythropoietic effects of ESA treatment and ESA resistance. Further research aimed at elucidating the causal pathways is strongly recommended. Given current knowledge, however, clinical practice should avoid disproportionately high dosages of ESAs to achieve recommended hemoglobin targets, particularly in those with significant cardiovascular morbidity or ESA resistance. The key to CKD anemia management will be individualization of the potential benefits of reducing blood transfusions and anemia-related symptoms against the risks of harm.

Association of the oral microbiome with cognitive function among older adults: NHANES 2011-2012.

BACKGROUND: An association between the gut microbiome and cognitive function has been demonstrated in prior studies. However, whether the oral microbiome, the second largest microbial habitant in humans, has a role in cognition remains unclear. DESIGN, SETTING, PARTICIPANTS: Using weighted data from the 2011 to 2012 National Health and Nutrition Examination Survey, we examined the association between oral microbial composition and cognitive function in older adults. The oral microbiome was characterized by 16S ribosomal RNA gene sequencing. Cognitive status was assessed using the Consortium to Establish a Registry for Alzheimer's Disease immediate recall and delayed recall, Animal Fluency Test, and Digit Symbol Substitution Test (DSST). Subjective memory changes over 12 months were also assessed. Linear and logistic regression models were conducted to quantify the association of α-diversity with different cognitive measurements controlling for potential confounding variables. Differences in ß-diversity were analyzed using permutational analysis of variance. RESULTS: A total of 605 participants aged 60-69 years were included in the analysis. Oral microbial α-diversity was significantly and positively correlated with DSST (ß, 2.92; 95% CI, 1.01-4.84). Participants with higher oral microbial α-diversity were more likely to have better cognitive performance status based on DSST (adjusted odds ratio, 2.35; 95% CI, 1.28-4.30) and were less likely to experience subjective memory changes (adjusted odds ratio, 0.43; 95% CI, 0.25-0.74). In addition, ß-diversity was statistically significant for the cognitive performance status based on DSST (P = 0.031) and subjective memory changes (P = 0.023). CONCLUSIONS: Oral microbial composition was associated with executive function and subjective memory changes among older adults among older U.S. adults in a nationally representative population sample. Oral dysbiosis is a potential biomarker or therapeutic target for cognitive decline. Further work is needed to elucidate the mechanisms underpinning the association between the oral microbiome and cognitive function.

Diabetes mellitus modifies the association between chronic kidney disease-mineral and bone disorder biomarkers and aortic stiffness in peritoneal dialysis patients.

This study aimed to investigate the relationship of four chronic kidney disease-mineral and bone disorder (CKD-MBD) biomarkers, including intact parathyroid hormone (PTH), fibroblast growth factor 23 (FGF23), soluble klotho, and fetuin-A, with aortic stiffness in peritoneal dialysis (PD) patients, comparing those with and without diabetes mellitus (DM). A total of 213 patients (mean age 58 ± 14 years; 81 (38.0%) patients with DM) were enrolled. Their aortic pulse wave velocity (PWV) was measured using pressure applanation tonometry, while serum intact PTH, FGF23, α-klotho, and fetuin-A levels were measured using enzyme-linked immunosorbent assay. Overall, patients with DM had higher aortic PWV than those without (9.9 ± 1.8 vs. 8.6 ± 1.4 m/s, p < 0.001). Among the four CKD-MBD biomarkers, FGF23 levels were significantly lower in DM group (462 [127-1790] vs. 1237 [251-3120] pg/mL, p = 0.028) and log-FGF23 independently predicted aortic PWV in DM group (ß: 0.61, 95% confidence interval: 0.06-1.16, p = 0.029 in DM group; ß: 0.10, 95% confidence interval: - 0.24-0.45, p = 0.546 in nonDM group; interaction p = 0.016). In conclusion, the association between FGF23 and aortic PWV was significantly modified by DM status in PD patients.