Blood pressure management in hemodialysis: what have we learned?

α-Blocker Use in Hemodialysis: The Japan Dialysis Outcomes and Practice Patterns Study

Rationale & Objective

Despite α-blockers' use for hypertension as add-on therapy in patients treated with hemodialysis, scant information is available on their association, particularly with safety, in these patients.

Study Design

Prospective cohort study.

Setting & Participants

patients treated with hemodialysis and receiving antihypertensive agents in the Japan Dialysis Outcomes and Practice Patterns Study, phases 4-6, were analyzed.

Exposure

Primary exposure was the prescription of α-blocking antihypertensive agents at baseline.

Outcomes

Incident fractures, falls, and all-cause mortality.

Analytical Approach

Multivariable Cox and modified Poisson regression analysis.

Results

Of 5,149 patients treated with hemodialysis (mean age, 65 years; 68% men) receiving antihypertensive drugs, 717 (14%) received α-blocking agents. During a mean follow-up period of 2.0 years, 247 fractures, 525 falls, and 498 deaths occurred. Multivariable analysis showed no significant association of α-blocker use and increased risk of fractures (hazard ratio [HR], 0.92 [95% confidence interval {CI}, 0.61-1.38]), falls (HR, 0.94 [95% CI, 0.74-1.20]), or all-cause deaths (HR, 0.87 [95% CI, 0.64-1.20]) compared with α-blocker nonuse. α-Blocker use was, however, significantly associated with a decreased risk of all-cause mortality in the subgroup analysis, for example, patients who were older (HR, 0.71 [95% CI, 0.51-0.99]), were women (HR, 0.68 [95% CI, 0.48-0.95]), or reported a history of cardiovascular disease (HR, 0.67 [95% CI, 0.48-0.95]) or a predialysis blood pressure of ≥140 mm Hg (HR, 0.69 [95% CI, 0.49-0.98]).

Limitations

Selection bias cannot be ruled out given the prevalent user analysis.

Conclusions

No significant association between α-blocker use and the risk of worse safety-related outcomes was seen, indicating that clinicians may safely prescribe α-blockers to patients receiving hemodialysis who require blood pressure lowering.

Plain-Language Summary

α-Blockers have been generally reserved for use as add-on therapy for resistant or refractory hypertension. However, little is known about the safety of α-blockers in patients treated by hemodialysis. We analyzed 5,149 patients receiving hemodialysis in Japan who were receiving antihypertensive drugs from the Japan Dialysis Outcomes and Practice Patterns Study. The results showed no significant increase in the risk of fractures, falls, or deaths for patients using α-blockers compared with those who did not, suggesting that α-blockers may be safely prescribed for patients receiving hemodialysis who need to lower their blood pressure.

The Value of CT Angiography Based on Intelligent Segmentation Algorithm for Survival of Hemodialysis Patients

This study was to explore the application value for central venous stenosis and occlusion in hemodialysis patients under the CT angiography based on intelligent segmentation algorithm, so that patients can survive better. Spiral CT was used to examine upper limb swelling in 62 uremic hemodialysis patients at a speed of 3.8 mL/s. Nonionic iodine contrast agent was injected around the contralateral limb. The total dosage of 90-102 mL, it was scanned by intelligent trigger technology. The trigger scanning threshold was set. The monitoring point was located in the superior vena cava. CT with convolutional neural network intelligent segmentation algorithm was used to process image data. Finally, the quality of life and related biochemical levels of patients before and after hemodialysis were detected. Under the CT angiography of intelligent segmentation algorithm, 77 stenoses were found in 62 uremic patients, including 48 stenoses of the brachial vein and 17 stenoses of the superior vena cava. The correlation coefficient between CT angiography and digital subtraction angiography (DSA) imaging results of intelligent segmentation algorithm was 0.411. Segmentation effect of the algorithm in this study: automatic segmentation accuracy was greater than 79%. After hemodialysis treatment, the scores of physical fitness, pain, social function, and energy status of patients were significantly increased compared with those before treatment, and the levels of albumin, serum phosphorus, and parathyroid hormone were significantly decreased (P < 0.05). In summary, CT angiography with intelligent segmentation algorithm can obtain clear, intuitive, and complete vascular walking images, and better display subclavian vein, brachiocephalic vein, and superior vena cava. It can provide more valuable support for surgical intervention and has certain application value for better survival of hemodialysis patients.

Blood Pressure Control and Antihypertensive Treatment among Hemodialysis Patients-Retrospective Single Center Experience

Background and Objectives: Hypertension affects at least 80% of hemodialysis patients. Inappropriate control of blood pressure is mentioned as one of the essential cardiovascular risk factors associated with development of cardiovascular events in dialysis populations. The aim of the cross-sectional, retrospective study was the evaluation of the antihypertensive treatment schedule and control of blood pressure in relation to the guidelines in the group of hemodialysis patients. Additionally, we assessed the level of decrease in blood pressure by each group of hypotensive agents. Materials and Methods: 222 patients hemodialyzed in a single Dialysis Unit in three distinct periods of time—2006, 2011, and 2016—with a diagnosis of hypertension were enrolled in the study. The analysis of the antihypertensive treatment was based on the medical files and it consisted of a comparison of the mean blood pressure results reported during the six consecutive hemodialysis sessions. Results: The mean values of blood pressure before hemodialysis were as follows: 134/77, 130/74, and 140/76 mmHg, after hemodialysis 124/74, 126/73, and 139/77 mmHg in 2006, 2011, and 2016 respectively. The goal of predialysis blood pressure control (<140/90) was achieved by up to 64.3% of participants in 2006 as compared to 49.4% in 2016. Additionally, the postdialysis goal (<130/90) reached 57.1% of the study population in 2006 as compared to 27.1% of patients in 2016. The differences in percentage of patients using single, double, triple, and multidrug therapy during observation were not statistically significant. The most often used drugs were ß-blockers, diuretics, and calcium channel blockers in all points of the study. Blockades of the renin–angiotensin–aldosterone system in 2006 and calcium channel blockers in 2011 and 2016 were the drugs with highest impact on lowering blood pressure. Conclusions: The goal of predialysis or postdialysis blood pressure control was achieved in a lower percentage of patients during the period of the study. Blockade of renin–angiotensin–aldosterone system and calcium channel blockers decrease the blood pressure significantly. It is necessary to achieve better control of blood pressure in prevention of cardiovascular incidents.

Dyselectrolytemia-management and implications in hemodialysis (Review)

Hemodialysis is a method for the renal replacement therapy followed by series of acute and chronic complications. Dyselectrolytemia appears in patients undergoing dialysis through mechanisms related to the chronic kidney disease and/or to the dialysis therapy and for this group of patients it is associated with an increase of morbidity and mortality. The dialysate has a standard composition, which can be modified according to the patient's characteristics. During hemodialysis patients are exposed to 18,000-36.000 litres of water/year, and the water purity along with the biochemical composition of the dialysate are essential. The individualization of the dialysis prescription is recommended for each patient and it has an important role in preventing the occurrence of dyselectrolyemia. The individualization of the treatment prescription according to the blood constants of each patient is the prerogative of the nephrologist and the association of the electrolyte imbalances with the patients cardiovascular mortality explains the importance of paying special attention to them.

Prevalence and Hypertension Treatment Schedule in Hemodialysis Patients and Renal Transplant Recipients in 2006 and 2014/2016

BACKGROUND

Hypertension is often recognized in both hemodialysis patients (HDp) and renal transplant recipients (RTRs). The aim of the study was the evaluation of hypertension prevalence and treatment schedule and the achievement of the control of blood pressure according to the Polish Society of Hypertension, European Society of Hypertension, Joint National Committee, and American College of Cardiology/American Heart Association 2017 recommendations.

MATERIALS AND METHODS

Observations were done in 2 distinct periods of time: the year 2006 and the years 2014/2016. In 2006, 56 HDp and 316 RTRs were studied. In 2014/2016, 85 HDp and 818 RTRs were studied. The antihypertensive treatment analysis was based on medical records from visits in RTRs and dialyses in HDp.

RESULTS

Cardiovascular diseases were diagnosed in 71.4% (2006) and 65.9% (2016) in HDp; 17.7% (2006) and 21.5% (2014) in RTRs. Diabetes was observed in 39.3% (2006) and 34.1% (2016) in HDp; 16.5% (2006) and 23.2% (2014) in RTRs. The target blood pressure control was achieved in 64.3% (2006) and 49.4% (2016) of HDp and in 61.4% (2006) and 45.7% (2014) of RTRs. Three drugs (28.6% and 33.5% in 2006; 30.6% and 29.1% in 2016/2014) or 2 antihypertensive drugs (19.6% and 26.9% in 2006; 22.4% and 27.1% in 2016/2014) were used in HDp and RTRs, respectively. The majority of HDp and RTRs were treated with ß-blockers followed by calcium channel blockers.

CONCLUSIONS

The target blood pressure control was achieved in a low percentage of HDp and RTRs. RTRs required multidrug antihypertensive therapy to control blood pressure more often than HDp.

Blood pressure targets for hemodialysis patients

The association between blood pressure (BP) and mortality is unique in hemodialysis patients compared with that in the general population. This is because of an altered benefit-risk balance associated with BP reduction in these patients. An adequately designed study comparing BP targets in hemodialysis patients remains to be conducted. The current evidence available to guide dialysis providers regarding treatment strategies for managing hypertension in this population is limited to large observational studies and small randomized controlled trials. In this opinion article, we review these data and discuss the key points regarding BP management for hemodialysis patients. Our aim is to provide a practical opinion regarding BP targets that nephrologists can incorporate into clinical practice, with a focus on moving away from dialysis unit BPs and focusing on out-of-dialysis unit BPs.

Management of Patient Care in Hemodialysis While Focusing on Cardiovascular Disease Events and the Atypical Role of Hyper- and/or Hypotension: A Systematic Review

Background. Hemodialysis related hemodynamic instability is a major but an underestimated issue. Moreover, cardiovascular events are the leading cause of morbidity and mortality associated with blood pressure in hemodialysis patients. However, there have been many controversies regarding the role and management of hyper- and/or hypotension during hemodialysis that needs to be addressed. Objective. To critically review the available published data on the atypical role of hyper- and/or hypotension in cardiovascular associated morbidity and mortality in patients on hemodialysis and to understand the discrepancies in this context. Methods. A comprehensive search of literature employing electronic as well as manual sources and screening 2783 papers published between Jan 1980 and Oct 2015 was conducted to collect, identify, and analyze relevant information through peer-reviewed research articles, systematic reviews, and other published works. The cardiovascular events, including accelerated atherosclerotic cardiovascular disease (ASCVD), stroke, heart failure, myocardial infarction, myocardial ischemia, and stress induced myocardial dysfunction, leading to death were considered relevant. Results. A total of 23 published articles met the inclusion criteria and were included for in-depth review and analysis to finalize a comprehensive systematic review article. All the studies showed a significant association between the blood pressure and cardiovascular disease events in hemodialysis patients. Conclusions. Both intradialytic hypertension/hypotension episodes are major risk factors for cardiovascular mortality with a high percentage of probable causality; however, clinicians are faced with a dilemma on how to evaluate blood pressure and treat this condition.

Hypertension Management in Transition: From CKD to ESRD

Hypertension is present in ∼90% of patients in late-stage CKD. There are scarce data focusing on the transition period between CKD Stages 4 and 5 (end-stage kidney disease) as it relates to hypertension evaluation and management. Here, we propose that a combination of the principles used in the management of patients with CKD Stages 4 and 5 be applied to patients in this transition. These include the use of out-of-office blood pressure (BP) monitoring (eg, home BP), avoidance of excessively tight BP goals, emphasis of sodium restriction, preferential use of blockers of the renin-angiotensin system and diuretics, and consideration of the use of beta blockers.

How should we manage adverse intradialytic blood pressure changes?

Variations in intradialytic blood pressure (BP) are a common and predictable occurrence in ESRD patients. These are caused by a decrease in blood volume provoked by ultrafiltration, lack of normal compensatory responses to fluid removal, underlying cardiac disease, and electrolyte changes that may adversely affect cardiovascular function. Intradialytic hypotension is the most frequent complication of the hemodialysis (HD) procedure and is fundamentally a consequence of an ultrafiltration rate that surpasses mechanisms activated to avert a decline in BP. Intradialytic hypertension is a less well-understood problem that has been recently associated with increased mortality. Fundamental patient characteristics and components of the HD procedure are involved in the pathophysiology of intradialytic hypotension and intradialytic hypertension. Correction of patient factors, modulation of HD prescription, and management of pharmacologic agents are the strategies to deal with adverse intradialytic BP changes.

Ideal timing and predialysis nephrology care duration for dialysis initiation: from analysis of Japanese dialysis initiation survey

Previous studies have suggested that early initiation of dialysis therapy was not superior in terms of patient survival. In this study, we analyzed the effects of renal function at the start of renal replacement therapy (RRT), duration of nephrology care, and comorbidity on 12-month survival of end-stage renal disease (ESRD) patients. The subjects in this study were 9695 new ESRD patients who started RRT in 2007. The average age of the subjects was 67.5 years, 64.1% of the subjects were male, and 42.9% had diabetes. During the 12-month period after the start of RRT, 1546 patients died, and 35 patients received renal transplantation. Average estimated glomerular filtration rate (eGFR) at the initiation of dialysis was 6.52 ± 4.20 mL/min/1.73 m(2) . By unadjusted logistic analysis, one-year Odds Ratio (OR) of mortality in patients with eGFR more than 4-6 mL/min/1.73 m(2) was increased with increased eGFR at dialysis initiation, but the OR was identical among the groups with eGFR less than 4 mL/min/1.73 m(2) . After adjustment for age, gender, underlying renal diseases, and other clinical characteristics at dialysis initiation, OR was identical among the groups with eGFR less than 8 mL/min/1.73 m(2) . Furthermore, an OR increment was observed in eGFR less than 4 mL/min/1.73 m(2) group. In terms of the duration of nephrology care before dialysis initiation, 6 months or longer of nephrology care significantly decreased the OR of mortality after adjustment of covariance. Not only patients with sufficient residual renal function at the initiation of dialysis, but also patients with very low eGFR at the initiation of dialysis showed poor survival.

Preservation of residual renal function with limited water removal in hemodialysis patients

Residual renal function (RRF) is of paramount importance for hemodialysis (HD) adequacy, morbidity, and mortality. Some studies have shown that overhydration is beneficial for preservation of RRF, but it can also increase the probability of adverse events such as hypertension and heart failure in HD patients. To determine the optimal amount of dehydration, we performed HD with limited water removal in HD patients. Eighteen HD patients included in this self-controlled study underwent HD with limited water removal. Water removal volume was determined by a previous volume as follows. Total water removal volume was divided into levels: ≤3.0, 3.0-9.0, and >9.0 L per week. Water removal was performed to obtain dry weight in the last dialysis, and was performed three times with a ratio of 1:1:2 and 2:2:3, respectively. Urine volume, endogenous creatinine clearance rate, Kt/V, hemoglobin, and serum albumin were recorded before and after the study at 3, 6, 9, and 12 months. The follow-up period was 12 months. Ten patients withdrew from the study because of adverse events including hypertension (n = 3), heart failure (n = 3), angina (n = 1), polycystic kidney rupture (n = 1), obvious edema (n = 1), and one patient had too much interdialytic weight gain to continue. As a result, we stopped this study after 1 month. Our data suggest that the preservation of RRF with limited water removal in HD patients must be interpreted with caution.