Cohort Of Dialysis Patients Research Articles

Impact of serum potassium on therapeutic prognosis of maintenance hemodialysis patients on angiotensin receptor antagonists

In chronic kidney disease patients, angiotensin receptor blockers (ARBs) have been known to increase serum potassium (K) levels. On the other hand, it has been reported that in patients on maintenance dialysis, both hyperkalemia and hypokalemia were related to poor prognosis. In this study, the prognosis with ARB treatment was investigated using a prospective cohort of dialysis patients that were divided into two groups according to pre-dialysis serum K levels: these were the low serum K group (below 4.6 mEq/L) and the high serum K group (4.6 mEq/L and higher). A total of 260 patients in our dialysis database were classified into four groups according to their serum K level and ARB use. The survival curves of these groups were estimated by Kaplan–Meier method and compared using a log-rank test. Using Cox regression model, prognostic factors for all-cause mortality were extracted from background factors, including the three classifications; high serum K and ARB group that served as the control. In terms of all-cause mortality rates, the low serum K and ARB group had the highest, whereas the high serum K and ARB group had the lowest. In the Cox regression model, all three classifications, except the control group, were factors for poor prognosis. In this study, pre-dialysis serum K level and ARB use affected all-cause mortality of dialysis patients. Multi-center prospective randomized study will be needed in the future to validate our findings.

Outcomes following surgery for fractured neck of femur in dialysis patients: a 5-year review from a district general hospital in the United Kingdom

BackgroundNeck of femur fractures are associated with high mortality and have increased prevalence in dialysis patients. Delays in operating on dialysis patients can occur as a result of logistical or medical issues; it has previously been shown that delays on operating on neck of femur fractures in the general population results in increased mortality.MethodsMedical records of 27 dialysis patients admitted to a large district general hospital in the UK with a fractured neck of femur between January 2009 and January 2014 were analysed alongside records of 27 age and sex-matched non-dialysis patients. Fisher’s exact test and the unpaired t test were applied to data to explore outcomes. Odds ratio was also used to compare mortality between the dialysis and non-dialysis groups.ResultsThirty-day mortality amongst dialysis patients was 22 %, compared to 7 % in the non-dialysis cohort. One-year mortality amongst dialysis patients was 70 %, compared to 15 % in the non-dialysis cohort (odds ratio 13.7 (3.56–52.4, 95 % confidence interval; p = 0.0001)). Average length of survival in dialysis patients overall was 311 days; average length of survival if the patient was operated on within 48 h of admission was 450 days (192–708 days, 95 % confidence interval) and was 224 days (45–402, 95 % confidence interval) if operated on after more than 48 h of admission (p = 0.16).ConclusionsDialysis patients had higher post-operative mortality than the non-dialysis cohort. Odds ratio for death was significantly greater at one-year in the cohort of dialysis patients compared to the non-dialysis patients. Delay to operation amongst the dialysis patient cohort did not contribute significantly to mortality in this study. The higher rates of coronary artery disease, diabetes mellitus and malignancy may confound mortality amongst patients on dialysis who sustain a fractured neck of femur. Limitations of this study included small patient numbers, data from only one centre being used, and some missing data for certain patients.

Postdialysis Hypertension: Associated Factors, Patient Profiles, and Cardiovascular Mortality.

A postdialytic increase in blood pressure (BP) is a recognized but often an overlooked complication. The epidemiology and predisposing factors are still not well defined. We studied a large sample of Italian dialysis patients to assess the prevalence of postdialysis hypertension (PDHYPER), defined as any increase of systolic BP (SBP) >10mm, Hg above the predialysis value, the associated factors and its role in cardiovascular (CV) mortality. In this observational study, we assessed dialysis associated changes in BP in 4,292 hemodialysis (HD) patients over 1 month (51,504 sessions). We compared the clinical characteristics of the patients with stable BP values during the HD session with those with PDHYPER. We also assessed the impact of PDHYPER on CV mortality. A total of 994 (23.1%) patients had PDHYPER. Patients with PDHYPER were more likely to be hypertesive, older, have a shorter dialysis vintage, be male, have lower SBP, lower changes in weight during HD, and receive more antihypertensive medications. These predictive factors were shown to be associated with an interaction between weight loss and dialysis, suggesting a volume-related mechanism in its pathogenesis. PDHYPER was also associated with CV mortality. In our study on a large Italian cohort of dialysis patients, the prevalence of PDHYPER was higher than what was previously reported and is a significant risk factor for CV mortality in dialysis patients. The pathogenesis is multifactorial but hypertensive state, antihypertensive medications, and extracellular volume expansion appear to play a major role.

Serum Cardiac Troponin-I is Superior to Troponin-T as a Marker for Left Ventricular Dysfunction in Clinically Stable Patients with End-Stage Renal Disease.

BackgroundSerum troponin assays, widely used to detect acute cardiac ischemia, might be useful biomarkers to detect chronic cardiovascular disease (CVD). Cardiac-specific troponin-I (cTnI) and troponin-T (cTnT) generally detect myocardial necrosis equally well. In dialysis patients however, serum cTnT levels are often elevated, unlike cTnI levels. The present study aims to elucidate the associations of cTnI and cTnT with CVD in clinically stable dialysis patients.MethodsTroponin levels were measured using 5th generation hs-cTnT assays (Roche) and STAT hs-cTnI assays (Abbott) in a cohort of dialysis patients. Serum troponin levels were divided into tertiles with the lowest tertile as a reference value. Serum troponins were associated with indicators of CVD such as left ventricular mass index (LVMI), left ventricular ejection fraction (LVEF) and the presence of coronary artery disease (CAD). Associations were explored using regression analysis.ResultsWe included 154 consecutive patients, 68±7 years old, 77% male, 70% hemodialysis. Median serum cTnT was 51ng/L (exceeding the 99th percentile of the healthy population in 98%) and median serum cTnI was 13ng/L (elevated in 20%). A high cTnI (T3) was significantly associated with a higher LVMI (Beta 31.60; p=0.001) and LVEF (Beta -4.78; p=0.005) after adjusting for confounders whereas a high serum cTnT was not. CAD was significantly associated with a high cTnT (OR 4.70 p=0.02) but not with a high cTnI. Unlike cTnI, cTnT was associated with residual renal function (Beta:-0.09; p=0.006).ConclusionIn the present cohort, serum cTnI levels showed a stronger association with LVMI and LVEF than cTnT. However, cTnT was significantly associated with CAD and residual renal function, unlike cTnI. Therefore, cTnI seems to be superior to cTnT as a marker of left ventricular dysfunction in asymptomatic dialysis patients, while cTnT might be better suited to detect CAD in these patients.

Soluble Klotho is not independently associated with cardiovascular disease in a population of dialysis patients.

BackgroundDialysis patients suffer from a high burden of cardiovascular disease (CVD). Partly this is due to progressive deterioration of calcium-phosphate homeostasis. Previous studies suggested that besides FGF-23, low levels of Klotho, a protein linked to aging, might constitute a key factor in this detrimental relationship. The purpose of the present study was to determine the relationship between serum Klotho (sKlotho) and the presence of CVD in dialysis patients.MethodsPlasma levels of sKlotho were measured in a cohort of dialysis patients and related to left ventricular (LV) dysfunction (defined as a LV ejection fraction <45%) and LV mass using echocardiography. Coronary artery disease (CAD) and calcification score were assessed using computed tomography angiography. Abdominal aortic calcification score (AACscore) was measured by abdominal X-ray.ResultsWe included 127 dialysis patients, 67 ± 7 years old, 76% male, 67% on hemodialysis, median sKlotho 460 pg/mL (25th-75th percentile 350-620 pg/mL). Patients with a low sKlotho (<460 pg/mL) showed significantly more CAD (81% versus 61%; p = 0.02) and LV dysfunction (19% versus 3%; p < 0.01). However, after adjusting for confounders, sKlotho was not independently associated with the presence of CVD or the AACscore.ConclusionsIn the present cohort of dialysis patients, sKlotho was not independently associated with CVD. However, patients with a low sKlotho level (<460 pg/mL) did show CAD and LV dysfunction more frequently. Therefore, while sKlotho might be a marker for CVD in dialysis patients, the current data does not support a direct cardioprotective effect of sKlotho.

Phenotypes Influencing Low Physical Activity in Maintenance Dialysis

The "Pas à Pas" initiative aimed at evaluating the weekly physical activity (PA) and its determinants in a large cohort of dialysis patients. Physical inactivity is a risk factor for mortality in maintenance dialysis patients and is still poorly documented in this population. A prospective national epidemiological study was performed. A total of 1,163 patients on maintenance dialysis (hemodialysis and peritoneal dialysis) were included. PA was recorded during seven consecutive days using a pedometer to measure daily step numbers. Median age was 63 years (Q1 51-Q3 75). Sixty-three percent were sedentary (<5000 steps/day) with a median of 3,688 steps/day (1,866-6,271)]. PA level was similar between hemodialysis patients and those on peritoneal dialysis (3,693 steps [1,896-6,307] vs. 3,320 [1,478-5,926], P=.33). In hemodialysis patients, PA was lower on dialysis days compared with nondialysis days (2,912 [1,439-5,232] vs. 4,054 [2,136-7,108], respectively, P<.01). PA gradually decreased with age, 57% being sedentary between 50 and 65years and 83% of patients after 80years. Beyond this age effect, we identified, for the first time, specific phenotypes of patients with lower PA, such as inflammation, cardiovascular disease, protein energy wasting, obesity, and diabetes. By contrast, previous kidney transplantation and a higher muscle mass were associated with higher PA. Dialysis patients present a very low level of PA with high sedentary. Acting on patient's modifiable phenotypes may help to increase PA to improve morbidity, mortality, and quality of life.

Erythropoiesis-stimulating agents and thrombotic events in dialysis patients

BackgroundErythropoiesis-stimulating agents (ESA) have been associated with a higher cardiovascular event and mortality rate in dialysis patients. The ESA-associated risk of arterial thrombotic events is mainly based on composite endpoints of anemia-correction trials targeting high hemoglobin levels. The ESA-associated risk of venous thromboembolism (VTE) has not been studied in dialysis patients yet. We therefore aimed to determine the association between ESA use and dose with ischemic stroke, myocardial infarction (MI) and VTE. Materials and MethodsIn NECOSAD, a Dutch cohort study of incident dialysis patients, data on ESA use and dose, comorbidities and laboratory parameters were routinely collected every 6months. Thrombotic events were collected by chart review of all dialysis patients from 6 participating centers. Time-dependent Cox regression analysis was performed to calculate hazard ratios (HR) with 95% confidence interval (CI) for ischemic stroke, MI and VTE with updated information on ESA use and dose. ResultsPatients with ESA had a 2 times lower ischemic stroke rate than patients without ESA: adjusted HR 0.45 (95% CI 0.23-0.90), and an adjusted HR of 1.12 (95% CI 0.58-2.14) for MI. No evident ESA dose response effect was present. Unadjusted HR for VTE was 0.41 (95% CI 0.11-1.50) for patients with ESA compared to patients without, but the low event rate made further adjustments impossible. ConclusionsIn our observational cohort of dialysis patients, reflecting everyday clinical practice, ESA was not associated with an excess of thrombotic events. Further investigation is needed to enlighten the true cause of ESA-associated cardiovascular events and mortality.

Survival, Morbidity, Sensitisation and Retransplantation Outcomes in a Cohort of Dialysis Patients After Renal Graft Loss Treated at a Single Centre With Protocolised Immunotherapy and Graft Nephrectomy By Indication.

Survival, Morbidity, Sensitisation and Retransplantation Outcomes in a Cohort of Dialysis Patients After Renal Graft Loss Treated at a Single Centre With Protocolised Immunotherapy and Graft Nephrectomy By Indication.

Utilization and Costs of Medications Associated With CKD Mineral and Bone Disorder in Dialysis Patients Enrolled in Medicare Part D

Information is limited regarding utilization patterns and costs for chronic kidney disease-mineral and bone disorder (CKD-MBD) medications in Medicare Part D-enrolled dialysis patients. Retrospective cohort study. Annual cohorts of dialysis patients, 2007-2010. Cohort year, low-income subsidy status, and dialysis provider. Utilization and costs of prescription phosphate binders, oral and intravenous vitamin D analogues, and cinacalcet. Using logistic regression, we calculated adjusted odds of medication use for low-income subsidy versus non-low-income subsidy patients and for patients from various dialysis organizations, and we report per-member-per-month and average out-of-pocket costs. Phosphate binders (∼83%) and intravenous vitamin D (77.5%-79.3%) were the most commonly used CKD-MBD medications in 2007 through 2010. The adjusted odds of prescription phosphate-binder, intravenous vitamin D, and cinacalcet use were significantly higher for low-income subsidy than for non-low-income subsidy patients. Total Part D versus CKD-MBD Part D medication costs increased 22% versus 36% from 2007 to 2010. For Part D-enrolled dialysis patients, CKD-MBD medications represented ∼50% of overall net Part D costs in2010. Inability to describe utilization and costs of calcium carbonate, an over-the-counter agent not covered under Medicare Part D; inability to reliably identify prescriptions filled through a non-Part D reimbursement or payment mechanism; findings may not apply to dialysis patients without Medicare Part D benefits or with Medicare Advantage plans, or to pediatric dialysis patients; could identify only prescription drugs dispensed in the outpatient setting; inability to adjust for MBD laboratory values. Part D net costs for CKD-MBD medications increased at a faster rate than costs for all PartDmedications in dialysis patients despite relatively stable use within medication classes. In a bundled environment, there may be incentives to shift to generic phosphate binders and reduce cinacalcet use.

How do hospitalization patterns of home hemodialysis patients compare with a reasonably well dialysis patient cohort?

BackgroundThe home hemodialysis (HHD) treatment option has been associated with improved patient outcomes compared to in-center hemodialysis (ICHD) programs. What is not quite clear is the influence of patient selection bias on the perceived benefits of HHD. The purpose of this study was to explore the potential benefits of HHD by comparing the admission patterns of HHD patients with a control group from a reasonably well dialysis patient cohort, which in this case were satellite hemodialysis patients on a Category 1 transplant waiting list (Cat1 SHD).MethodsA single center retrospective randomized cohort study of HHD and Cat1 SHD patients who were on these two treatment modalities from August 2012 to August 2013 was performed to obtain a sample of 25 patients for each group.ResultsThe mean length of stay in hospital was 5.9 days for HHD patients and 6.7 days for Cat1 SHD group (P=0.8). Eighteen admissions were observed for both groups (0.72 admissions/patient-year; P=0.5). HHD patients spent 71 days and Cat1 SHD patients spent 85 days in hospital (2.8 and 3.4 days/patient-year respectively; P<0.005). The mean serum potassium level for HHD patients was 4.1 (3.1–6.5) mEq/L versus 5.0 (3.7–6.1) mEq/L for Cat1 SHD patients (P=0.001) and the mean phosphate level was 1.1 (0.56–2.38) mg/dL and 1.5 (0.43–3.2) mg/dL (P=0.02) for the respective groups.ConclusionThis study confirms the superiority of the HHD treatment option in improving patient outcomes. Admission patterns of HHD patients fared very well against a control group which consisted of reasonably well dialysis patients.

The association of ECG and echocardiographic abnormalities with sudden cardiac death in a dialysis patient cohort

Cardiovascular mortality is greater in dialysis patients than the general population. More specifically, sudden cardiac death (SCD) accounts for 26% of dialysis patient deaths. However, SCD risk assessment tools used in the general population are not adequate for dialysis patients indicating that the hierarchy of pathopysiological factors appears to be different. The aim of this study was to use simple bedside tests to determine parameters independently predictive of cardiovascular mortality and SCD in dialysis patients. This was a sub-study of the Chronic Renal Insufficient Standards Implementations Study, a longitudinal cohort study of outcomes in CKD. ECG and echocardiographic abnormalities were assessed in a cross-section of prevalent dialysis patients. Patients were followed up until death or transplantation. Forward stepwise Cox regression then determined factors independently associated with all-cause, cardiovascular and SCD mortality. 323 patients were included (age 61.5 ± 14.6years, 113 deaths, 66 cardiovascular deaths, 18 SCD). A number of factors were independently associated with all-cause mortality. These were age, time on dialysis, smoking, the difference between QRS and T-wave axes, resting heart rate, and pulmonary artery pressure (PAP) >35mmHg. The only parameters predictive of SCD were elevated PAP (HR=5.99, p=0.05) and mitral regurgitation (HR=6.71, p=0.01). That PAP is associated with SCD in dialysis patients demonstrates that the pathophysiological mechanism is likely to be different in these patients compared to the general population. Because of this, a population specific approach to risk stratification is advisable.

Predicting risk of mortality in dialysis patients: a retrospective cohort study evaluating the prognostic value of a simple chest X-ray

BackgroundClinical outcomes of dialysis patients are variable, and improved knowledge of prognosis would inform decisions regarding patient management. We assessed the value of simple, chest X-ray derived measures of cardiac size (cardiothoracic ratio (CTR)) and vascular calcification (Aortic Arch Calcification (AAC)), in predicting death and improving multivariable prognostic models in a prevalent cohort of hemodialysis patients.MethodsEight hundred and twenty-four dialysis patients with one or more postero-anterior (PA) chest X-ray were included in the study. Using a validated calcification score, the AAC was graded from 0 to 3. Cox proportional hazards models were used to assess the association between AAC score, CTR, and mortality. AAC was treated as a categorical variable with 4 levels (0,1,2, or 3). Age, race, diabetes, and heart failure were adjusted for in the multivariable analysis. The criterion for statistical significance was p<0.05.ResultsThe median CTR of the sample was 0.53 [IQR=0.48,0.58] with calcification scores as follows: 0 (54%), 1 (24%), 2 (17%), and 3 (5%). Of 824 patients, 152 (18%) died during follow-up. Age, sex, race, duration of dialysis, diabetes, heart failure, ischemic heart disease and baseline serum creatinine and phosphate were included in a base Cox model. Both CTR (HR 1.78[1.40,2.27] per 0.1 unit change), area under the curve (AUC)=0.60[0.55,0.65], and AAC (AAC 3 vs 0 HR 4.35[2.38,7.66], AAC 2 vs 0 HR 2.22[1.41,3.49], AAC 1 vs 0 HR 2.43[1.64,3.61]), AUC=0.63[0.58,0.68]) were associated with death in univariate Cox analysis. CTR remained significant after adjustment for base model variables (adjusted HR 1.46[1.11,1.92]), but did not increase the AUC of the base model (0.71[0.66,0.76] vs. 0.71[0.66,0.76]) and did not improve net reclassification performance (NRI=0). AAC also remained significant on multivariable analysis, but did not improve net reclassification (NRI=0). All ranges were based on 95% confidence intervals.ConclusionsNeither CTR nor AAC assessed on chest x-ray improved prediction of mortality in this prevalent cohort of dialysis patients. Our data do not support the clinical utility of X-ray measures of cardiac size and vascular calcification for the purpose of mortality prediction in prevalent hemodialysis patients. More advanced imaging techniques may be needed to improve prognostication in this population.

Age-dependent parathormone levels and different CKD-MBD treatment practices of dialysis patients in Hungary - results from a nationwide clinical audit

BackgroundAchieving target levels of laboratory parameters of bone and mineral metabolism in chronic kidney disease (CKD) patients is important but also difficult in those living with end-stage kidney disease. This study aimed to determine if there are age-related differences in chronic kidney disease-mineral and bone disorder (CKD-MBD) characteristics, including treatment practice in Hungarian dialysis patients.MethodsData were collected retrospectively from a large cohort of dialysis patients in Hungary. Patients on hemodialysis and peritoneal dialysis were also included. The enrolled patients were allocated into two groups based on their age (<65 years and ≥65 years). Characteristics of the age groups and differences in disease-related (epidemiology, laboratory, and treatment practice) parameters between the groups were analyzed.ResultsA total of 5008 patients were included in the analysis and the mean age was 63.4±14.2 years. A total of 47.2% of patients were women, 32.8% had diabetes, and 11.4% were on peritoneal dialysis. Diabetes (37.9% vs 27.3%), bone disease (42.9% vs 34.1%), and soft tissue calcification (56.3% vs 44.7%) were more prevalent in the older group than the younger group (p<0.001 for all). We found an inverse relationship between age and parathyroid hormone (PTH) levels (p<0.001). Serum PTH levels were lower in patients with diabetes compared with those without diabetes below 80 years (p<0.001). Diabetes and age were independently associated with serum PTH levels (interaction: diabetes × age groups, p=0.138). Older patients were more likely than younger patients to achieve laboratory target ranges for each parameter (Ca: 66.9% vs 62.1%, p<0.001; PO4: 52.6% vs 49.2%, p<0.05; and PTH: 50.6% vs 46.6%, p<0.01), and for combined parameters (19.8% vs 15.8%, p<0.001). Older patients were less likely to receive related medication than younger patients (66.9% vs 79.7%, p<0.001).ConclusionsThe achievement of laboratory target ranges for bone and mineral metabolism and clinical practice in CKD depends on the age of the patients. A greater proportion of older patients met target criteria and received less medication compared with younger patients.

Survival in dialysis patients is different between patients with diabetes as primary renal disease and patients with diabetes as a co-morbid condition

A previous study in Dutch dialysis patients showed no survival difference between patients with diabetes as primary renal disease and those with diabetes as a co-morbid condition. As this was not in line with our hypothesis, we aimed to verify these results in a larger international cohort of dialysis patients. For the present prospective study, we used data from the European Renal Association-European Dialysis and Transplant Association (ERA-EDTA) Registry. Incident dialysis patients with data on co-morbidities (n = 15,419) were monitored until kidney transplantation, death or end of the study period (5 years). Cox regression was performed to compare survival for patients with diabetes as primary renal disease, patients with diabetes as a co-morbid condition and non-diabetic patients. Of the study population, 3,624 patients (24%) had diabetes as primary renal disease and 1,193 (11%) had diabetes as a co-morbid condition whereas the majority had no diabetes (n = 10,602). During follow-up, 7,584 (49%) patients died. In both groups of diabetic patients mortality was higher compared with the non-diabetic patients. Mortality was higher in patients with diabetes as primary renal disease than in patients with diabetes as a co-morbid condition, adjusted for age, sex, country and malignancy (HR 1.20, 95% CI 1.10, 1.30). An analysis stratified by dialysis modality yielded similar results. Overall mortality was significantly higher in patients with diabetes as primary renal disease compared with those with diabetes as a co-morbid condition. This suggests that survival in diabetic dialysis patients is affected by the extent to which diabetes has induced organ damage.

CLINICAL BIOCHEMISTRY DATABASE ANALYSIS: A RESTRICTED DIALYSIS COHORT /

Summary Background: A retrospective study was undertaken to inves- tigate the biochemistry data of a restricted cohort of dialysis- related arthropathy patients. The aim of our study was to characterize this specific cohort of dialysis patients using a clinical chemistry database analysis. Methods: An elaboration of more than 160,000 items of biochemical data, collected from 2001 to 20|11, was made of 50 patients, 25 with dialysis-related arthropathy and 25 patients asymptomatic for arthropathy. A Student's t-test was applied, considering a P-value less than 0.05 as statistically significant. Results: Significant and relevant unexpected biochemical dif- ferences were found between the two groups of patients. The serum level of p2-microglobulin was similar, while fer- ritin values were significantly higher in symptomatic patients. We excluded the possibility that the ferritin difference between the two groups was due to different iron storage and to an inflammatory profile. Conclusions: The correct use of a biochemical database could permit to identify significant values which must be cor- related with clinical data, but which could be the first step to a wider research.

An ethical approach to dialysis--an alliance of nephrology, palliative medicine and ethics

One of the miracles of modern medicine alongside such remarkable advances as anaesthesia and antibiotics is dialysis. Millions of lives have been prolonged by dialysis and those lives extended have had an incalculable impact on the individuals concerned and their family, friends and society generally. However, as humans, we know that miraculous good may bring its own set of challenges. From a technology that was, at its inception, carefully reserved for younger, fitter non-diabetic patients, dialysis has, at least in developed nations, been available to the entire population. Therein lies the quandary that increasingly faces clinicians in the use of modern technologies, including dialysis: which patients with end-stage kidney disease (ESKD) will benefit from dialysis and who might suffer? What ethical principles guide this decision making? In what circumstances is a conservative or non-dialytic management of ESKD appropriate? What is the role of palliative medicine? The answers to those questions often lead to other deeper issues—what is the manner and nature of the lives of patients with ESKD irrespective of their management and ultimately what is the manner of their deaths? Any discussion about the medical and ethical dimensions of dialysis should begin with an acknowledgement of three truths—epidemiology, mortality and uncertainty. When dialysis units were first established, dialysis was reserved for younger, fitter patients. That situation has changed significantly—the number, age and comorbidity of these patients have all increased. Indeed, throughout the developed world, the cohort of dialysis patients with the greatest prevalence now are aged 65–84 years.1–3 A further critical issue is mortality. Receiving dialysis does not guarantee a normal life span. International data show high mortality in elderly patients initiating dialysis.4 Small studies suggest that for patients in the 75 and above age group, there is little if any survival advantage of commencing dialysis, over …

Impact of Race on Cumulative Exposure to Antihypertensive Medications in Dialysis

Racial minorities typically have less exposure than non-minorities to antihypertensive medications across an array of cardiovascular conditions in the general population. However, cumulative exposure has not been investigated in dialysis patients. In a longitudinal analysis of 38,381 hypertensive dialysis patients, prescription drug data from Medicaid was linked to Medicare data contained in United States Renal Data System core data, creating a national cohort of dialysis patients dually eligible for Medicare and Medicaid services. The proportion of days covered (PDC) was calculated to determine cumulative exposure to angiotensin converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs), β-blockers, and calcium-channel blockers (CCDs). The factors associated with use of these medications were modeled through weighted linear regression, with derivation of the adjusted odds ratios (AORs) for exposure. Relative to non-Hispanic Caucasians, African-American, Hispanic, or Other race/ethnicity were significantly associated with less exposure to β-blockers (AOR 0.56-0.69, P < 0.001 in each case) and CCBs (AOR 0.84-0.85, P < 0.001 in each case); African-American race and Hispanic ethnicity had AORs of 0.78 and 0.73 for ACEIs and ARBs, respectively (P < 0.001 in both cases). Collectively, the odds of exposure to each class of medication for minorities was about three-quarters of that for Caucasians. Given that dually Medicare-and-Medicaid-eligible dialysis patients have insurance coverage for prescription medications as well as regular contact with health care providers, differences by race in exposure to antihypertensive medications should with time be minimal among patients who are candidates for these drugs. The causes of differences by race in exposure to antihypertensive medications over the course of time should be further examined.

The fat-mass and obesity-associated gene (FTO) predicts mortality in chronic kidney disease of various severity

Polymorphisms in the FTO (fat-mass and obesity-associated) gene have been associated with the body mass index, cancer, type 2 diabetes and hypertension. We investigated the relationship between 17 tag single-nucleotide polymorphisms (SNPs) and all-cause mortality in three cohorts of dialysis patients (CREED-1, North Apulian and CREED-2 cohorts; n = 783) and in one cohort of stage 2-5 CKD patients (n = 757). We first explored the association between the 17 tag SNPs and all-cause mortality in the CREED-1 cohort and found that patients with the A allele of the FTO rs708259 polymorphism had an elevated risk of mortality (hazard ratio, HR: 1.52, 95% confidence interval (CI) 1.11-2.08; P = 0.008). Similarly, the A allele was associated with an increased risk of death also in the other two dialysis cohorts (North Apulian cohort, risk: +23%; CREED-2 cohort, risk: +21%). The elevated risk portended by this allele was even higher in the stage 2-5 CKD cohort (+97%). However, the risk of mortality associated with the A allele in the three confirmatory cohorts failed to achieve formal statistical significance. In a meta-analysis including the four cohorts (n = 1540; total deaths, n = 381), individuals with the A allele had a 42% excess risk of death (HR: 1.42, 95% CI 1.14-1.76, P = 0.002). The A allele of the FTO rs708259 polymorphism is an independent predictor of all-cause mortality in patients with CKD of various severity. These data support our hypothesis that the FTO gene may be a relevant genetic risk factor for mortality in this population.

Application of Gadolinium-Based Contrast Agents and Prevalence of Nephrogenic Systemic Fibrosis in a Cohort of End-Stage Renal Disease Patients on Hemodialysis

Background/Aims: Nephrogenic systemic fibrosis (NSF) is a highly debilitating disease that can occur in patients with reduced kidney function after application of gadolinium-based contrast agents (GBCA). In recent years, the incidence of the disease has significantly decreased. The aim of this study was to assess the prevalence of NSF in a cohort of dialysis patients and to investigate whether the use of GBCA has changed in this patient cohort. Methods: We studied 508 dialysis patients from 8 centers in the Ruhr area, Germany. Patients were visited during dialysis, and anamnestic data were collected by interview, from patient files and, if necessary, from radiological institutes. Patients were examined for cutaneous changes of NSF, which were defined using a scoring system based on hyperpigmentation, hardening, and tethering of skin of the extremities. Results: 4/508 patients were clinically suspected of NSF, yet only 2 had received GBCA and their diagnosis was confirmed dermatohistologically (0.4%). The other 2 had not received GBCA, and hence NSF was not suspected. Between 2006 and 2010, 49/508 patients underwent an MRI. 25/49 patients received GBCA. The relative proportion of MRIs with GBCA was highest in 2006 (9/13; 69.2%) and lowest in 2009 (6/16; 37.5%). The proportion of linear chelates (gadodiamide and gadopentetate dimeglumine) was highest in 2006 (8/9; 88.9%) and lower thereafter. Conclusion: The prevalence of NSF in our cohort of dialysis patients is very low. This may be the consequence of a progressively restricted use of GBCA in patients with impaired kidney function and a more widespread application of macrocyclic chelates.

Vascular access type and risk of mortality in a national prospective cohort of haemodialysis patients

Central venous catheters (CVC) are a potential source of bacteraemia and have been associated with increased mortality in haemodialysis patients. We aimed to investigate the relationships between haemodialysis vascular access, taking into account changes in vascular access type during patients' lives, and cause specific mortality risk in a national cohort of dialysis patients. Prospective cohort study including all patients receiving haemodialysis in Scotland at annual cross sectional surveys in 2009, 2010 and 2011. Data were collected through the Scottish Renal Registry and by a structured review of case records following death. Cox proportional hazards regression and multivariable logistic regression were used to model survival and risk of death from septicaemia respectively. Of a cohort of 2666 patients, 873 (32%) died during follow-up. After case-mix adjustment, patients using only tunnelled CVC during follow-up had a higher risk of all cause mortality across all strata of prior renal replacement therapy exposure [adjusted hazard ratio (HR): 1.83-2.08]. Case-mix adjusted risks of cardiovascular death (adjusted HR: 2.20-2.95) and infection-related death (adjusted HR: 3.10-3.63) were also higher in this group. Patients using tunnelled CVCs during follow-up and prior to death had 6.9-fold higher odds of death from septicaemia compared with those using only arteriovenous fistulae or grafts. Compared with an arteriovenous fistula or graft, sustained use of tunnelled CVCs for vascular access is associated with higher risks of all-cause, cardiovascular and infection-related mortality.