Mild chronic kidney disease and functional impairment in community-dwelling older adults.

BACKGROUND: chronic kidney disease (CKD) has been associated with an increased risk of death and cardiovascular events, but its relationship with non-vascular outcomes, including functional impairment (FI), is less well understood. OBJECTIVE: in this study, we review the association between CKD and FI, adjusting for potential confounders and risk factors, with a primary outcome of impairment in any instrumental ADL (IADL) or basic ADL (BADL). DESIGN: the Cardiovascular Multimorbidity in Primary Care Study (CLARITY) is a cross-sectional study of community-dwelling adults. SETTING: participants were adults living in the West of Ireland attending university-affiliated general practices. SUBJECTS: all participants were adults aged ≥50 years living in the community. METHODS: CKD was defined as an estimated glomerular filtration rate (eGFR) ≤60 ml/min/1.73 m(2). A standardised self-reported health questionnaire to measure activities of daily living (ADL) was completed by participants. Logistic regression analyses were used to determine the independent association between CKD and FI. RESULTS: a total of 3,499 patients were included with a mean age of 66.2 ± 10.3 years. 18.0% (n = 630) had CKD (mean eGFR 50.2 ± 9.2 ml/min/1.73m(2)), 21.9% (n = 138) of which had a diagnosis of CKD documented in medical records. 40.4% (n = 1,413) reported FI and multivariable adjustment showed CKD to be independently associated with FI (OR: 1.43, 1.15-1.78), impairment in IADL (OR: 1.43, 1.15-1.78) and impairment in BADL (OR: 1.39, 1.11-1.75). CONCLUSION: our study shows even mild CKD is associated with FI, independent of age, gender, co-morbidities, traditional vascular risk factors and cardiovascular events.

Sudden cardiac death in dialysis: do current guidelines for implantable cardioverter defibrillator therapy apply to patients with end-stage kidney disease?

Arrhythmic mechanisms account for one in four deaths in end-stage kidney disease. Large-scale randomized controlled trials have demonstrated a mortality benefit from implantable cardioverter defibrillator therapy in carefully selected patient groups at high risk for sudden cardiac death. Unfortunately, patients with end-stage kidney disease were systematically excluded from these trials. Consequently, the applicability of American College of Cardiology (ACC)/American Heart Association (AHA)/Heart Rhythm Society (HRS) guidelines on implantable cardioverter defibrillator therapy to dialysis patients remains uncertain. Observational data suggest that secondary preventative implantable cardioverter defibrillator therapy following resuscitated cardiac arrest prolongs the lives of dialysis patients. This intervention may also offer a survival advantage as a primary preventative strategy in end-stage kidney disease. However, competing risk from co-morbidity can negate any perceived benefit. Device-related complications also negatively impact outcome. The recommendation that primary preventative device implantation be reserved for patients with severely impaired left ventricular function may be excessively restrictive in this high-risk population. Trials of implantable cardioverter defibrillator therapy that include dialysis patients are required to validate existing device eligibility criteria in this unique population. Novel indications for this intervention in dialysis patients should also be identified.

Dialysis Patients' Preferences on Resuscitation: A Cross-Sectional Study Design.

Background: End-stage kidney disease is associated with a 10- to 100-fold increase in cardiovascular mortality compared with age-, sex-, and race-matched population. Cardiopulmonary resuscitation (CPR) in this cohort has poor outcomes and leads to increased functional morbidity. Objective: The aim of this study is to assess patients' preferences toward CPR and advance care planning (ACP). Design: cross-sectional study design. Setting: Two outpatient dialysis units. Patients: Adults undergoing dialysis for more than 3 months were included. Exclusion criteria were severe cognitive impairment or non-English-speaking patients. Measurements: A structured interview with the use of Willingness to Accept Life-Sustaining Treatment (WALT) tool. Methods: Demographic data were collected, and baseline Montreal Cognitive Assessment, Patient Health Questionnaire-9, Duke Activity Status Index, Charlson comorbidity index, and WALT instruments were used. Descriptive analysis, chi-square, and t test were performed along with probability plot for testing hypotheses. Results: Seventy participants were included in this analysis representing a 62.5% response rate. There was a clear association between treatment burden, anticipated clinical outcome, and the likelihood of that outcome with patient preferences. Low-burden treatment with expected return to baseline was associated with 98.5% willingness to accept treatment, whereas high-burden treatment with expected return to baseline was associated with 94.2% willingness. When the outcome was severe functional or cognitive impairment, then 45.7% and 28.5% would accept low-burden treatment, respectively. The response changed based on the likelihood of the outcome. In terms of resuscitation, more than 75% of the participants would be in favor of receiving CPR and mechanical ventilation at their current health state. Over 94% of patients stated they had never discussed ACP, whereas 59.4% expressed their wish to discuss this with their primary nephrologist. Limitations: Limited generalizability due to lack of diversity. Unclear decision stability due to changes in health status and patients' priorities. Conclusions: ACP should be incorporated in managing chronic kidney disease (CKD) to improve communication and encourage patient involvement.

Mise en contexte: Les patients atteints d'insuffisance rénale terminale voient leur taux de mortalité cardiovasculaire augmenté de 10 à 100 fois par rapport à une population appariée selon l'âge, le sexe et l'origine ethnique. La réanimation cardiorespiratoire (RCR) donne de mauvais résultats dans cette cohorte de patients et conduit à une morbidité fonctionnelle accrue. Objectif de l'étude: Évaluer les préférences des patients en matière de RCR et de planification préalable des soins (PPS). Conception: Étude transversale. Cadre et type d'étude: Deux unités de dialyse pour patients ambulatoires. Patients: Ont été inclus les adultes suivant des traitements de dialyse pendant plus de trois mois. Les patients non anglophones ou ayant des troubles cognitifs graves ont été exclus. Mesures: Une entrevue structurée réalisée à l'aide de l'outil WALT (Willingness to Accept Life-Sustaining Treatment). Méthodologie: Des données démographiques ont été recueillies et les outils d'évaluation suivants ont été utilisés à l'inclusion: le Montreal Cognitive Assessment, le questionnaire sur la santé des patients (PHQ-9), le Duke Activity Status Index, l'indice de comorbidité de Charlson et l'outil WALT. Des analyses descriptives, tests de chi carré et tests de t ont été effectués, ainsi que des graphiques de probabilité pour tester les hypothèses. Résultats: Soixante-dix participants ont été inclus dans l'analyse, soit un taux de réponse de 62.5%. On a observé une association claire entre les préférences du patient et le fardeau du traitement, le résultat clinique attendu et la probabilité de ce résultat. La probabilité qu'un patient accepte un traitement représentant un faible fardeau, avec un retour à l'état initial prévu, s'établissait à 98.5%; cette probabilité était de 94.2% pour un traitement avec retour à l'état initial, mais représentant un lourd fardeau. Lorsqu'un traitement de faible fardeau était susceptible d'entraîner une déficience fonctionnelle ou cognitive grave, cette probabilité passait respectivement à 45.7% et 28.5%. La réponse variait en fonction de la probabilité du résultat. En ce qui concerne la réanimation, plus de 75% des participants seraient favorables à la RCR et à la ventilation mécanique dans leur état de santé actuel. Plus de 94% des patients n'avaient jamais discuté de PPS avec leur néphrologue principal, alors que 59.4% ont exprimé leur souhait de le faire. Limites de l'étude: Généralisabilité limitée en raison du manque de diversité. Stabilité incertaine des décisions en raison de l'évolution de l'état de santé et des priorités des patients. Conclusion: La PPS devrait être intégrée à la prise en charge de l'insuffisance rénale chronique afin d'améliorer la communication avec les patients et d'encourager leur participation.

Burden of chronic kidney disease and rapid decline in renal function among adults attending a hospital-based diabetes center in Northern Europe.

INTRODUCTION: This study aimed to determine the prevalence of diabetic kidney disease (DKD) and rapid renal function decline and to identify indices associated with this decline among adults attending a diabetes center in Northern Europe. RESEARCH DESIGN AND METHODS: This is a retrospective cohort study of 4606 patients who attended a diabetes center in Ireland between June 2012 and December 2016. Definition/staging of chronic kidney disease used the Kidney Disease: Improving Global Outcomes (KDIGO) 2012 classification based on data from the most recently attended appointment. Relevant longitudinal trends and variabilities were derived from serial records prior to index visit. Rapid renal function decline was defined based on per cent and absolute rates of estimated glomerular filtration rate (eGFR) change. Multiple linear regression was used to explore the relationships between explanatory variables and per cent eGFR change. RESULTS: 42.0% (total), 23.4% (type 1 diabetes), 47.9% (type 2 diabetes) and 32.6% (other diabetes) had DKD. Rapid decline based on per cent change was more frequent in type 2 than in type 1 diabetes (32.8% vs 14.0%, p<0.001). Indices independently associated with rapid eGFR decline included older age, greater number of antihypertensives, higher log-normalized urine albumin to creatinine ratio (LNuACR), serum alkaline phosphatase, thyroid stimulating hormone, variability in systolic blood pressure and variability in LNuACR, lower glycated hemoglobin, high-density lipoprotein cholesterol and diastolic blood pressure, and lack of ACE inhibitor/angiotensin receptor blocker prescription. CONCLUSIONS: DKD (using the KDIGO 2012 classification) and rapid eGFR decline were highly prevalent among adults attending a hospital-based diabetes clinic in a predominantly Caucasian Northern European country. The burden was greater for adults with type 2 diabetes. Expected as well as potentially novel clinical predictors were identified.

Decreased pulse pressure during hemodialysis is associated with improved 6-month outcomes.

Pulse pressure is a well established marker of vascular stiffness and is associated with increased mortality in hemodialysis patients. Here we sought to determine if a decrease in pulse pressure during hemodialysis was associated with improved outcomes using data from 438 hemodialysis patients enrolled in the 6-month Crit-Line Intradialytic Monitoring Benefit Study. The relationship between changes in pulse pressure during dialysis (2-week average) and the primary end point of non-access-related hospitalization and death were adjusted for demographics, comorbidities, medications, and laboratory variables. In the analyses that included both pre- and post-dialysis pulse pressure, higher pre-dialysis and lower post-dialysis pulse pressure were associated with a decreased hazard of the primary end point. Further, every 10 mm Hg decrease in pulse pressure during dialysis was associated with a 20% lower hazard of the primary end point. In separate models that included pulse pressure and the change in pulse pressure during dialysis, neither pre- nor post-dialysis pulse pressure were associated with the primary end point, but each 10 mm Hg decrease in pulse pressure during dialysis was associated with about a 20% lower hazard of the primary end point. Our study found that in prevalent dialysis subjects, a decrease in pulse pressure during dialysis was associated with improved outcomes. Further study is needed to identify how to control pulse pressure to improve outcomes.

Increased Weight Gain During the Long Interdialytic Period Is Associated with Minor Effects on Blood Pressure Control in Clinically Stable In-Centre Haemodialysis Patients.

BACKGROUND/AIMS: Three-day-a-week chronic haemodialysis (cHD) involves 1 long (72 h) and 2 short (48 h) inter-dialytic periods (IDPs). We aimed to determine whether BP control following the long IDP is inferior to the short IDPs. METHODS: All pre- and post-dialysis BP and weight measurements over a 4-week period were retrospectively analyzed among 135 clinically stable cHD patients at 2 academic centres with comparisons between measurements recorded following short and long IDPs. Subsequently, 23 clinically stable cHD patients underwent 24-h ambulatory blood pressure monitoring (ABPM) during the final day/night cycle of the long IDP and 1 short IDP within the same week. RESULTS: In combined and separate analyses of the 2 retrospective cohorts, pre-dialysis BP parameters were not different following long and short IDPs despite greater inter-dialytic weight gain (IDWG) during the long IDP. Subgroup analyses of the total cohort showed no evidence for inferior BP control during the long IDP among those with high %IDWG. In the ABPM study, nocturnal hypertension and loss of nocturnal dipping were frequent. Furthermore, daytime systolic blood pressure (SBP) and pulse pressure were modestly higher during the last day/night cycle of the long compared with short IDP. CONCLUSION: In stable cHD patients, the greater IDWG that occurred during the long IDP was not associated with overtly inferior BP control as reflected in pre-dialysis BP measurements. However, modestly higher daytime SBP was evident towards the end of the long IDP by 24 h ABPM. Thus, while fluid gain has well-documented associations with hypertension and adverse cardiovascular outcomes, the excess IDWG that occurs during the long IDP exerts relatively minor effects on BP control in patients on well-established dialysis regimens that are better identified by ambulatory monitoring.

Secondary analysis of the CHOIR trial epoetin-alpha dose and achieved hemoglobin outcomes.

Trials of anemia correction in chronic kidney disease have found either no benefit or detrimental outcomes of higher targets. We did a secondary analysis of patients with chronic kidney disease enrolled in the Correction of Hemoglobin in the Outcomes in Renal Insufficiency trial to measure the potential for competing benefit and harm from achieved hemoglobin and epoetin dose trials. In the 4 month analysis, significantly more patients in the high-hemoglobin compared to the low-hemoglobin arm were unable to achieve target hemoglobin and required high-dose epoetin-alpha. In unadjusted analyses, the inability to achieve a target hemoglobin and high-dose epoetin-alpha were each significantly associated with increased risk of a primary endpoint (death, myocardial infarction, congestive heart failure or stroke). In adjusted models, high-dose epoetin-alpha was associated with a significant increased hazard of a primary endpoint but the risk associated with randomization to the high hemoglobin arm did not suggest a possible mediating effect of higher target via dose. Similar results were seen in the 9 month analysis. Our study demonstrates that patients achieving their target had better outcomes than those who did not; and among subjects who achieved their randomized target, no increased risk associated with the higher hemoglobin goal was detected. Prospective studies are needed to confirm this relationship and determine safe dosing algorithms for patients unable to achieve target hemoglobin.

Quality of care and practice patterns in anaemia management at specialist kidney clinics in Ireland: a national study.

BACKGROUND: Although anaemia is a common complication of advanced chronic kidney disease (CKD), knowledge of quality of care and management practices in specialist clinics varies. We examined anaemia practices at specialist nephrology clinics within the Irish health system and evaluated the opinions of practicing nephrologists. METHODS: A multicentre cross-sectional study was conducted at specialist nephrology clinics across six geographic regions in Ireland. Clinical characteristics and treatment practices were evaluated in a sample of 530 patients with CKD. An accompanying national survey questionnaire captured opinions and treatment strategies of nephrologists on anaemia management. RESULTS: The prevalence of anaemia [defined as haemoglobin (Hb) <12.0 g/dL] was 37.8%, which increased significantly with advancing CKD (from 21% to 63%; P < 0.01) and varied across clinical sites (from 36% to 62%; P < 0.026). Iron deficiency (ID) was present in 46% of all patients tested and 86% of them were not on treatment. More than 45% of anaemic patients were not tested for ID. Respondents differed in their selection of clinical guidelines, threshold targets for erythropoiesis-stimulating agent (ESA) and intravenous iron therapy and anaemia management algorithms were absent in 47% of the clinics. The unexpectedly low rates of ESA use (4.7%) and iron therapy (10.2%) in clinical practice were in contrast to survey responses where 63% of nephrologists indicated ESA therapy initiation when Hb was <10.0 g/dL and 46% indicated commencement of iron therapy for ferritin <150 ng/mL. CONCLUSION: This study highlights substantial variability in the management of anaemia and ID at specialist nephrology clinics with low testing rates for ID, high rates of anaemia and ID and underutilization of effective treatments. Variability in the adoption and implementation of different clinical guidelines was evident.

Prognostic implications of abnormalities in renal function in patients with acute coronary syndromes.

BACKGROUND: Outcomes in patients with mild to moderate renal function (RF) abnormalities presenting with acute coronary syndromes (ACS) are not well defined. METHODS AND RESULTS: A convenience sample of 4 ACS trial databases including all enrolled patients was assessed to determine 30- and 180-day outcomes. The 4 trials were Global Use of Strategies to Open Occluded Coronary Arteries (GUSTO) IIb, GUSTO-III, Platelet Glycoprotein IIb/IIIa in Unstable Angina: Receptor Suppression Using Integrilin Therapy (PURSUIT), and Platelet IIb/IIIa Antagonism for the Reduction of Acute coronary syndrome events in a Global Organization Network (PARAGON-A). Patients were stratified into ST-segment elevation (STE) and non-ST-segment elevation (NSE) groups and by the presence or absence of abnormal RF (creatinine clearance <70 mL/min). In the STE group, 7670 of 18 621 patients (41%) had abnormal RF. In the NSE group, 8152 of 19 304 (42%) had abnormal RF. Patients with abnormal RF were older, more often female, and more likely to have adverse baseline characteristics. They had higher mortality and higher mortality/nonfatal myocardial infarction (MI) at both 30 and 180 days, regardless of ST-segment status. Creatinine clearance was independently associated with risk of mortality (hazard ratio 0.79 in the STE group and 0.81 in the NSE group) and with risk of mortality/MI (hazard ratio 0.93) in the NSE group at 180 days. CONCLUSIONS: Patients presenting with ACS frequently have abnormal RF. Abnormal RF is a marker of adverse baseline clinical characteristics and is independently associated with increased risk of death and death/MI.

Treatment of acute coronary syndromes in patients who have chronic kidney disease.

Patients with CKD and CAD have traditionally been a difficult population to diagnose and treat in the setting of ACS. In addition to having poorer outcomes post-ACS, data are lacking regarding best treatments available. Aggressive interventional and medical treatments in this group with already poor outcomes are not necessarily contraindicated and should always be considered. The appalling outcome for CKD patients post-ACS is improved by many therapies shown to benefit in the non-CKD patients. Data suggest that troponins are useful markers in CKD patients, that major bleeding is not increased with the use of GP IIb-IIIa antagonists, that thrombolytics have been used successfully in CKD patients, and that PCI electively and as a primary treatment for ACS is successful and probably more beneficial to treatment.

Cardiovascular disease and chronic kidney disease: insights and an update.

Despite the high prevalence and significant morbidity and mortality rates of chronic kidney disease (CKD) related to cardiovascular disease, it remains vastly understudied. Most of the current practice recommendations come from small under-powered prospective studies, retrospective reviews, and assuming patients with CKD will similarly benefit from medications and treatments as patients with normal renal function. In addition, because of the previous lack of a consistent definition of CKD and how to measure renal function, definitions of the degree of renal dysfunction have varied widely and compounded the confusion of these data. Remarkably, despite patients with CKD representing the group at highest risk from cardiovascular complications, even greater than patients with diabetes mellitus, there has been a systematic exclusion of patients with CKD from therapeutic trials. This review outlines our current understanding of CKD as a cardiovascular risk factor, treatment options, and the future directions that are needed to treat cardiovascular disease in patients with CKD.

Beneficial effect of plasmapheresis and intravenous immunoglobulin on renal allograft survival of patients with acute humoral rejection.

BACKGROUND: Acute humoral rejection (AHR) has been associated with enhanced graft loss. Our study compared the renal allograft survival of patients with AHR treated with plasmapheresis (PP) and intravenous immunoglobulin (IVIG) with allograft survival in patients with acute cellular rejection (ACR). METHODS: We retrospectively analyzed all kidney transplants performed at our institution between January 1999 and August 2001 (n=286). Recipients were classified into three groups according to biopsy reports: AHR, ACR, or no rejection. The ACR group was further divided into early and late rejection (<90 and >90 days posttransplant, respectively). RESULTS: After a mean follow-up of 569+/-19 days, the incidence of AHR was 5.6% (n=16). Recipient presensitization, delayed graft function, early rejection, and higher creatinine at diagnosis were characteristic of AHR. Most AHR patients (14/16) were treated with PP and IVIG. One patient received only IVIG, whereas another received only PP. All AHR patients were given steroid pulses, but only four received antilymphocyte therapy because of concomitant severe ACR. The ACR group comprised 43 patients (15%). One patient with mild rejection received no therapy, 20 improved with steroids alone, and 22 required additional antilymphocyte therapy. One-year graft survival by Kaplan Meier analysis was 81% and 84% in the AHR and ACR groups, respectively (P=NS). Outcomes remained similar when AHR patients were compared with those with early ACR. CONCLUSIONS: We conclude that AHR, when diagnosed early and treated aggressively with PP and IVIG, carries a short-term prognosis that is similar to ACR.

Treatment effects of eptifibatide in planned coronary stent implantation in patients with chronic kidney disease (ESPRIT Trial).

The role of platelet glycoprotein IIb/IIIa inhibitor therapy in patients with mild renal impairment is not well characterized. Our objective was to explore the associations of creatinine clearance (CrCl) with outcomes in a trial of eptifibatide therapy in patients who underwent percutaneous coronary intervention (PCI). We analyzed 48-hour and 30-day outcomes of patients enrolled in the Enhanced Suppression of the Platelet IIb/IIIa Receptor with Integrilin Therapy (ESPRIT) trial. Patients were randomly assigned to placebo or eptifibatide as an adjunct to stent implantation (1,755 with CrCl > or =60 ml/min and 289 with CrCl <60 ml/min). CrCl was calculated using the Cockcroft and Gault formula, and the associations of CrCl with outcomes were evaluated using logistic regression models. Patients with CrCl <60 ml/min were more likely to be older, women, hypertensive, and have a history of coronary artery bypass surgery, stroke, or peripheral vascular disease. The interaction of eptifibatide with CrCl had borderline significance for the 30-day outcome (p = 0.109). Treatment effect trended toward a greater magnitude in patients with lower CrCl (60 ml/min) (odds ratio 0.53, confidence interval 0.34 to 0.83) compared with those with higher CrCl (90 ml/min) (odds ratio 0.68, confidence interval 0.49 to 0.94). An accompanying increase in bleeding risk also was not apparent with lower CrCl. The treatment effect of eptifibatide is realized regardless of renal function and trends toward being greater in patients with mild renal impairment.

Characteristics of treated hypertension in incident hemodialysis and peritoneal dialysis patients.

BACKGROUND: The treatment of hypertension in dialysis patients is prevalent and poorly characterized. beta-Blockers and calcium channel blockers (CCBs) have been associated with reduced all-cause and cardiovascular mortality. This study describes the treatment of hypertension and assesses the association between mortality and class of antihypertensive medication among a cohort of dialysis patients. METHODS: The US Renal Data System (USRDS) Dialysis Morbidity and Mortality Study Wave II cohort was analyzed. A total of 2,877 patients initiating hemodialysis or peritoneal dialysis in 1996 or 1997 and treated with antihypertensives were included in this analysis. Vital status was followed until November 2000. RESULTS: Calcium channel blockers were prescribed to 70.3% of patients. Only 31.5% and 27.0% of patients with cardiovascular disease were prescribed angiotensin-converting enzyme inhibitors and beta-blockers, respectively. Mono-, double-, triple-, and more than triple-therapy were reported in 48.0%, 36.1%, 13.2%, and 2.7% of the cohort, respectively. In multivariable, fully adjusted models, no individual class of antihypertensives was associated with changes in all-cause mortality. In all patients, nondihydropyridine CCBs (non-DHP CCBs) were associated with a reduced risk of cardiovascular death (hazard ratio, 0.78; 95% confidence interval, 0.62 to 0.97) and among end-stage renal disease patients with preexisting cardiovascular disease, dihydropyridine CCBs (DHP CCBs) and non-DHP CCBs were associated with reduced risk of all-cause and cardiovascular mortality. CONCLUSION: Calcium channel blocker use is widespread among hypertensive dialysis patients. Antihypertensive prescription patterns suggest a lack of consensus regarding treatment of hypertension. Multivariable analysis of associations between antihypertensive class and mortality reveals results of uncertain clinical significance. Hypertension treatment trials in dialysis patients should be performed to appropriately inform treatment decisions.

Sodium intake and renal outcomes: a systematic review.

BACKGROUND: Sodium intake is an important determinant of blood pressure; therefore, reduction of intake may be an attractive population-based target for chronic kidney disease (CKD) prevention. Most guidelines recommend sodium intake of < 2.3 g/day, based on limited evidence. We reviewed the association between sodium intake and renal outcomes. METHODS: We reviewed cohort studies and clinical trials, which were retrieved by searching electronic databases, that evaluated the association between sodium intake/excretion and measures of renal function, proteinuria, or new need for dialysis. RESULTS: Of 4,337 reviewed citations, seven (n = 8,129) were eligible, including six cohort studies (n = 7,942) and one clinical trial (n = 187). Four studies (n = 1,787) included patients with CKD. All four cohort studies reported that high intake (> 4.6 g/day) was associated with adverse outcomes (vs. moderate/low), while none reported an increased risk with moderate intake (vs. low). Three studies (n = 6,342) included patients without CKD. Two cohort studies (n = 6,155) reported opposing directions of association between low (vs. moderate) sodium intake and renal outcomes, and one clinical trial (n = 187) reported a benefit from low intake (vs. moderate) on proteinuria but an adverse effect on serum creatinine. CONCLUSIONS: Available, but limited, evidence supports an association between high sodium intake (> 4.6g/day) and adverse outcomes. However, the association with low intake (vs. moderate) is uncertain, with inconsistent findings from cohort studies. There is urgent need to clarify the long-term efficacy and safety of currently recommended low sodium intake in patients with CKD.

Blood pressure measurement in peritoneal dialysis: which method is best?

BACKGROUND: The optimal approach to monitoring blood pressure (BP) in the peritoneal dialysis (PD) population is unclear. Ambulatory BP monitoring reliably predicts prognosis, but can be inconvenient. The accuracy of home BP monitoring in this population is unproven. The automated BpTRU device (BpTRU Medical Devices, Coquitlam, BC, Canada), which provides an average of up to 6 successive in-office BP measurements, has not been studied in this patient group. METHODS: We studied 17 patients (average age: 54 ± 12 years; 12 men, 5 women; 94% on automated PD) attending a single center. All patients underwent office, home, BpTRU, and ambulatory BP measurement. The reference standard for analysis was daytime ambulatory BP. Correlation between the referent method and each comparator method was determined (Pearson correlation coefficient), and Bland-Altman scatter plots depicting the differences in the BP measurements were constructed. RESULTS: Mean office BP (126.4 ± 16.9/78.8 ± 11.6 mmHg) and BpTRU BP (123.8 ± 13.7/80.7 ± 11.1 mmHg) closely approximated mean daytime ambulatory BP (129.3 ± 14.8/78.2 ± 7.9 mmHg). Mean home BP (143.8 ± 15.0/89.9 ± 28.1 mmHg) significantly overestimated mean daytime systolic BP by 14.2 mmHg (95% confidence interval: 4.3 mmHg to 24.1 mmHg; p = 0.008). Bland-Altman plots demonstrated poorest agreement between home BP and daytime ambulatory BP. No patient had "white-coat hypertension," and only 1 patient had false-resistant hypertension. Most patients showed abnormal nocturnal dipping patterns (non-dipping: n = 11; reverse-dipping: n = 5; normal dipping: n = 1). CONCLUSIONS: We report a novel finding that BP measurement using the BpTRU device is more accurate than home BP measurement in a PD population. Potential explanations for this observation include poor home BP measurement technique, use of poorly validated home BP measurement devices, or a reduced prevalence of white-coat effect among PD patients. Our study also confirms that, in the PD population, BP measurements vary considerably with patient location, time of day, and measurement technique.

In-office assessment of blood pressure in chronic kidney disease: usual measurement versus automated BpTRU measurement.

OBJECTIVES: The automated BpTRU device has been shown to improve the accuracy of in-office blood pressure assessment in hypertensive populations. We aimed to determine whether this was also true for patients with chronic kidney disease. MATERIALS AND METHODS: We recorded the blood pressure of 80 hypertensive outpatients with chronic kidney disease by usual automated measurement and BpTRU automated measurement. We established whether there were any statistically significant differences in the absolute blood pressure values measured by either method and whether these differences had any impact on the assessment of blood pressure control. RESULTS: Systolic and diastolic blood pressures were significantly lower by BpTRU measurement than by usual measurement, by 10.1±12.2 mmHg (95% confidence interval: 7.4-12.8 mmHg, P<0.001) and 2.8±10.6 mmHg (95% confidence interval: 0.4-5.1 mmHg, P=0.02), respectively. Significantly, more patients achieved their blood pressure target of 130/80 mmHg or less by BpTRU measurement than by usual measurement (72.5 vs. 48.8% for systolic blood pressure, P<0.001; 68.8 vs. 61.3% for diastolic blood pressure, P=0.02). Systolic blood pressures remained significantly lower by BpTRU measurement than by usual measurement in all predefined study subgroups (estimated glomerular filtration rate <30 vs ≥30 ml/min/1.73m; transplant vs. nontransplant). We detected more hypotension by BpTRU measurement than by usual measurement. CONCLUSION: Our study suggests that the BpTRU device can negate white coat effect in patients with chronic kidney disease. The use of this device in routine clinical practice could improve the overall accuracy of in-office blood pressure assessment in this high-risk population, minimizing the potential for undertreatment and overtreatment of hypertension.