Arterial stiffness and augmentation of aortic blood pressure (BP) measured in office are known cardiovascular risk factors in hemodialysis patients. This study examines the prognostic significance of ambulatory brachial BP, central BP, pulse wave velocity (PWV), and heart rate–adjusted augmentation index [AIx(75)] in this population. A total of 170 hemodialysis patients underwent 48-hour ambulatory monitoring with Mobil-O-Graph-NG during a standard interdialytic interval and followed-up for 28.1±11.2 months. The primary end point was a combination of all-cause death, nonfatal myocardial infarction, and nonfatal stroke. Secondary end points included: (1) all-cause mortality; (2) cardiovascular mortality; and (3) a combination of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, resuscitation after cardiac arrest, coronary revascularization, or hospitalization for heart failure. During follow-up, 37(21.8%) patients died and 46(27.1%) had cardiovascular events. Cumulative freedom from primary end point was similar for quartiles of predialysis-systolic BP (SBP), 48-hour peripheral-SBP, and central-SBP, but was progressively longer for increasing quartiles for 48-hour peripheral-diastolic BP and central-diastolic BP and shorter for increasing quartiles of 48-hour central pulse pressure (83.7%, 71.4%, 69.0%, 62.8% [log-rank P =0.024]), PWV (93.0%, 81.0%, 57.1%, 55.8% [log-rank P <0.001]), and AIx(75) (88.4%, 66.7%, 69.0%, 62.8% [log-rank P =0.014]). The hazard ratios for all-cause mortality, cardiovascular mortality, and the combined outcome were similar for quartiles of predialysis-SBP, 48-hour peripheral-SBP, and central-SBP, but were increasing with higher ambulatory PWV and AIx(75). In multivariate analysis, 48-hour PWV was the only vascular parameter independently associated with the primary end point (hazard ratios, 1.579; 95% confidence intervals, 1.187–2.102). Ambulatory PWV, AIx(75), and central pulse pressure are associated with increased risk of cardiovascular events and mortality, whereas office and ambulatory SBP are not. These findings further support that arterial stiffness is the prominent cardiovascular risk factor in hemodialysis.

Approximately 85% of hemodialysis patients are hypertensive, but less than 30% achieve adequate blood pressure (BP) control. Reduction of volume overload is fundamental for BP control, but clinical criteria to estimate dry-weight are inaccurate. In the present study we examined the effect of dry-weight reduction with a lung-ultrasound-guided strategy on ambulatory BP in 71 clinically euvolemic hemodialysis patients with hypertension. Patients were equally randomized into an active group, following a strategy for dry-weight reduction guided by pre-hemodialysis lung ultrasound, and a control group with standard-of-care treatment. All patients underwent 48-hour ambulatory BP monitoring (ABPM) at baseline and after eight weeks. Overall, more patients in the active than in the control group had dry weight reduction, 54.3% compared to 13.9%, respectively. The ultrasonographic-B line change during follow-up was significantly different (-5.3±12.5 in active versus D2.2±7.6 in control group), which corresponded to significant differences in dry weight changes between the groups. The magnitude of reductions in 48-hour systolic BP (-6.61±9.57 vs.-0.67±13.07) and diastolic BP (-3.85±6.34 vs.-0.55±8.28) was significantly greater in the active group. Similarly, intradialytic BP, 44-hour BP, and daytime or night-time systolic/diastolic BP during both days of the interdialytic interval were significantly reduced in the active group but remained unchanged in the control group. The percentage of patients experiencing one or more intradialytic hypotensive episodes was marginally lower in the active group (34.3% vs. 55.6%). Thus, a lung-ultrasound-guided strategy for dry-weight reduction can effectively and safely reduce ambulatory BP levels in hemodialysis patients. Clinical implementation of this simple technique can help increase BP control in this population.

Prevalence of anemia progressively increases with advancing stages of CKD and is higher in diabetic than matched non-diabetic CKD patients and diabetes is independently associated with anemia occurrence. Detection and treatment of anemia in diabetic CKD patients should be performed earlier than non-diabetic counterparts.

An increase in short-term SBP-variability was present with advancing CKD stages in a large cohort. This increased SBP-variability may be involved in the sharp elevation of cardiovascular risk with worsening renal function.

Volume overload in haemodialysis (HD) patients associates with hypertension and cardiac dysfunction and is a major risk factor for all-cause and cardiovascular mortality in this population. The diagnosis of volume excess and estimation of dry weight is based largely on clinical criteria and has a notoriously poor diagnostic accuracy. The search for accurate and objective methods to evaluate dry weight and to diagnose subclinical volume overload has been intensively pursued over the last 3 decades. Most methods have not been tested in appropriate clinical trials and their usefulness in clinical practice remains uncertain, except for bioimpedance spectroscopy and lung ultrasound (US). Bioimpedance spectroscopy is possibly the most widely used method to subjectively quantify fluid distributions over body compartments and produces reliable and reproducible results. Lung US provides reliable estimates of extravascular water in the lung, a critical parameter of the central circulation that in large part reflects the left ventricular end-diastolic pressure. To maximize cardiovascular tolerance, fluid removal in volume-expanded HD patients should be gradual and distributed over a sufficiently long time window. This review summarizes current knowledge about the diagnosis, prognosis and treatment of volume overload in HD patients.

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Background: Hyperkalemia is a potentially life-threatening disorder, usually complicating chronic kidney disease (CKD). Factors superimposed to reduced renal function are further elevating hyperkalemia risk, but their contribution is not fully elucidated. This study aimed to compare the prevalence of hyperkalemia in diabetic and non-diabetic patients with CKD. Methods: This is a nested case-control study of 180 type-2 diabetic and 180 non-diabetic patients with CKD followed in a Nephrology outpatient clinic, matched for gender, age and estimated glomerular filtration rate. Type-1 diabetes or end-stage renal disease patients were excluded. Prevalence of hyperkalemia was defined as potassium >5 mEq/l or use of sodium polystyrene sulfonate, and further by potassium >5, ≥5.2 and ≥5.5 mEq/l. It was calculated in both groups in whole and CKD stages separately. Univariate and multivariate logistic regression analysis were conducted to identify factors associated with hyperkalemia. Results: The prevalence of hyperkalemia was higher in diabetic CKD patients (27.2 vs. 20%, p = 0.107) and remained around 30% higher with all secondary definitions used, but never reached statistical significance. In Stage 2, no difference was noted (8.7 vs. 17.4%, p = 0.665); in Stage 3, it was significantly higher in diabetics (28.6 vs. 17.5%, p = 0.036); and in Stage 4, it was equally high in both groups (35.5 vs. 32.3%, p = 0.788). In multivariate analysis, Stage 4 CKD (OR 4.535, 95% CI 1.561-13.173), use of angiotensin-converting enzyme inhibitors (ACEIs; OR 2.228, 95% CI 1.254-3.958) and smoking (OR 2.254, 95% CI 1.218-4.171) were independently associated with hyperkalemia. Conclusions: Diabetes mellitus was found to elevate the prevalence of hyperkalemia only in CKD Stage 3 patients (moderately impaired renal function). Advanced CKD at Stage 4 and ACEIs are major determinants of hyperkalemia occurrence.

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