Calcium channel blockers for people with chronic kidney disease requiring dialysis

BACKGROUND

Calcium channel blockers (CCBs) are used to manage hypertension which is highly prevalent among people with chronic kidney disease (CKD). The treatment for hypertension is particularly challenging in people undergoing dialysis.

OBJECTIVES

To assess the benefits and harms of calcium channel blockers in patients with chronic kidney disease requiring dialysis.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies to 27 April 2020 through contact with the Information Specialist using search terms relevant to this review. Studies in the Specialised Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

All randomised controlled trials (RCTs) and quasi-RCTs that compared any type of CCB with other CCB, different doses of the same CCB, other antihypertensives, control or placebo were included. The minimum study duration was 12 weeks.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed study quality and extracted data. Statistical analyses were performed using a random-effects model and results expressed as risk ratio (RR), risk difference (RD) or mean difference (MD) with 95% confidence intervals (CI).

MAIN RESULTS

This review included 13 studies (24 reports) randomising 1459 participants treated with long-term haemodialysis. Nine studies were included in the meta-analysis (622 participants). No studies were performed in children or in those undergoing peritoneal dialysis. Overall, risk of bias was assessed as unclear to high across most domains. Random sequence generation and allocation concealment were at low risk of bias in eight and one studies, respectively. Two studies reported low risk methods for blinding of participants and investigators, and outcome assessment was blinded in 10 studies. Three studies were at low risk of attrition bias, eight studies were at low risk of selective reporting bias, and five studies were at low risk of other potential sources of bias. Overall, the certainty of the evidence was low to very low for all outcomes. No events were reported for cardiovascular death in any of the comparisons. Other side effects were rarely reported and studies were not designed to measure costs. Five studies (451 randomised adults) compared dihydropyridine CCBs to placebo or no treatment. Dihydropyridine CCBs may decrease predialysis systolic (1 study, 39 participants: MD -27.00 mmHg, 95% CI -43.33 to -10.67; low certainty evidence) and diastolic blood pressure level (2 studies, 76 participants; MD -13.56 mmHg, 95% CI -19.65 to -7.48; I² = 0%, low certainty evidence) compared to placebo or no treatment. Dihydropyridine CCBs may make little or no difference to occurrence of intradialytic hypotension (2 studies, 287 participants; RR 0.54, 95% CI 0.25 to 1.15; I² = 0%, low certainty evidence) compared to placebo or no treatment. Other side effects were not reported. Eight studies (1037 randomised adults) compared dihydropyridine CCBs to other antihypertensives. Dihydropyridine CCBs may make little or no difference to predialysis systolic (4 studies, 180 participants: MD 2.44 mmHg, 95% CI -3.74 to 8.62; I² = 0%, low certainty evidence) and diastolic blood pressure (4 studies, 180 participants: MD 1.49 mmHg, 95% CI -2.23 to 5.21; I² = 0%, low certainty evidence) compared to other antihypertensives. There was no evidence of a difference in the occurrence of intradialytic hypotension (1 study, 92 participants: RR 2.88, 95% CI 0.12 to 68.79; very low certainty evidence) between dihydropyridine CCBs to other antihypertensives. Other side effects were not reported. Dihydropyridine CCB may make little or no difference to predialysis systolic (1 study, 40 participants: MD -4 mmHg, 95% CI -11.99 to 3.99; low certainty evidence) and diastolic blood pressure (1 study, 40 participants: MD -3.00 mmHg, 95% CI -7.06 to 1.06; low certainty evidence) compared to non-dihydropyridine CCB. There was no evidence of a difference in other side effects (1 study, 40 participants: RR 0.13, 95% CI 0.01 to 2.36; very low certainty evidence) between dihydropyridine CCB and non-dihydropyridine CCB. Intradialytic hypotension was not reported.

AUTHORS' CONCLUSIONS

The benefits of CCBs over other antihypertensives on predialysis blood pressure levels and intradialytic hypotension among people with CKD who required haemodialysis were uncertain. Effects of CCBs on other side effects and cardiovascular death also remain uncertain. Dihydropyridine CCBs may decrease predialysis systolic and diastolic blood pressure level compared to placebo or no treatment. No studies were identified in children or peritoneal dialysis. Available studies have not been designed to measure the effects on costs. The shortcomings of the studies were that they recruited very few participants, had few events, had very short follow-up periods, some outcomes were not reported, and the reporting of outcomes such as changes in blood pressure was not done uniformly across studies. Well-designed RCTs, conducted in both adults and children with CKD requiring both haemodialysis and peritoneal dialysis, evaluating both dihydropyridine and non-dihydropyridine CCBs against other antihypertensives are required. Future research should be focused on outcomes relevant to patients (including death and cardiovascular disease), blood pressure changes, risk of side effects and healthcare costs to assist decision-making in clinical practice.

Peritoneal Total Protein Transport Assessed from Peritoneal Equilibration Tests Using Different Dialysate Glucose Concentrations

Background

The peritoneal equilibration test (PET) permits assessment of peritoneal protein transport, but this potential marker of outcome in peritoneal dialysis (PD) patients lacks adequate standardization.

Objectives

To assess various approaches for estimation of peritoneal protein transport in PD patients during 2.27% and 3.86% glucose-based PETs, and to uncover the demographic, clinical, and biochemical correlates of this phenomenon.

Patients and Methods

We studied 90 PD patients who underwent 2.27% and 3.86% PETs in random order, and we used multivariate analysis to compare assessments of peritoneal protein transport in both tests, searching for correlations between D240′– D0′protein concentration (PETΔPConc), total peritoneal protein excretion (PET-PPE), or total protein clearance (PET-PC) on the one hand (the main study variables), and PET-derived markers of peritoneal function and selected demographic, clinical, and biochemical variables on the other.

Results

The PETΔPConc was higher during the 2.27% PET (mean: 45.2 mg/dL vs 37.0 mg/dL for the 3.86% test; p = 0.003); the PET-PPE and PET-PC were comparable (1121.8 mg vs 1168.9 mg, p = 0.52, and 17.1 mL vs 17.8 mL, p = 0.66, respectively). All three variables sustained a significant, yet moderate correlation (all r2values < 0.30) with the 24-hour PPE rate. Multivariate analysis identified dialysate-to-plasma ratio (D/P240′) of creatinine, end-to-initial dialysate ratio (D240′/D0′) of glucose, current daily peritoneal glucose load, ultrafiltration during PET, systolic blood pressure, and previous cardiovascular events (3.86% test only) as independent predictors of protein transport during PET.

Conclusions

Either PET-PPE or PET-PC seems preferable to PETΔPConc for characterization of peritoneal protein transport. Small-solute transport characteristics, ultrafiltration, and current peritoneal glucose load sustain independent correlations with peritoneal protein transport. The latter variable shows also a moderate association with markers of cardiovascular disease in PD patients.

Impact of ACE Inhibitors and AII Receptor Blockers on Peritoneal Membrane Transport Characteristics in Long-Term Peritoneal Dialysis Patients

Background

Long-term peritoneal dialysis (PD) may lead to peritoneal fibrosis and ultrafiltration failure. The latter occurs due to high solute transport rates and diabetiform peritoneal sclerosis. Angiotensin-II (AII) is known to be a growth factor in the development of fibrosis and a number of animal studies have shown it likely that inhibiting the effects of AII by angiotensin-converting enzyme (ACE) or angiotensin receptor blocker (ARB) will attenuate these complications.

Objective

To investigate the effects of ACE/AII inhibitors in long-term PD patients.

Patients and Setting

We analyzed data from 66 patients treated with PD therapy at our center for at least 2 years, during which time at least 2 standard peritoneal permeability analyses (SPAs) were performed. 36 patients were treated with ACE/AII inhibitors (ACE/ARB group); the other 30 received none of the above drugs during the entire follow-up (control group). The two groups were compared with respect to changes in peritoneal transport over the follow-up time.

Results

A significant difference in time course of peritoneal transport was found between the 2 groups: in the ACE/ARB group, small solute transport had decreased, while it had increased in the control group. This finding was confirmed by analysis using mixed model for repeated measures. The value of mass transfer area coefficient of creatinine was influenced by the duration of PD therapy ( p = 0.017) and this interaction was different with respect to use of ACE/AII inhibitors ( p = 0.037). The trend was not found in protein clearances or fluid kinetics.

Conclusion

Our findings suggest that ACE/AII inhibition is likely to prevent the increase in mass transfer area coefficients that occurs in long-term PD, which is in line with results of experimental animal studies.

Effectiveness of Renin-Angiotensin-Aldosterone System Blockade on Residual Kidney Function and Peritoneal Membrane Function in Peritoneal Dialysis Patients: A Network Meta-Analysis

We performed a network meta-analysis of randomised controlled trials (RCTs) and non-randomised studies in adult peritoneal dialysis patients to evaluate the effects of specific renin-angiotensin aldosterone systems (RAAS) blockade classes on residual kidney function and peritoneal membrane function. Key outcome parameters included the following: residual glomerular filtration rate (rGFR), urine volume, anuria, dialysate-to-plasma creatinine ratio (D/P Cr), and acceptability of treatment. Indirect treatment effects were compared using random-effects model. Pooled standardised mean differences (SMDs) and odd ratios (ORs) were estimated with 95% confidence intervals (CIs). We identified 10 RCTs (n = 484) and 10 non-randomised studies (n = 3,305). Regarding changes in rGFR, RAAS blockade with angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin II receptor blockers (ARBs) were more efficacious than active control (SMD 0.55 [0.06–1.04] and 0.62 [0.19–1.04], respectively) with the protective effect on rGFR observed only after usage ≥12 months, and no differences among ACEIs and ARBs. Compared with active control, only ACEIs showed a significantly decreased risk of anuria (OR 0.62 [0.41–0.95]). No difference among treatments for urine volume and acceptability of treatment were observed, whereas evidence for D/P Cr is inconclusive. The small number of randomised studies and differences in outcome definitions used may limit the quality of the evidence.

Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers for preserving residual kidney function in peritoneal dialysis patients

BACKGROUND

Angiotensin-converting enzyme inhibitors (ACEis) and angiotensin receptor blockers (ARBs) are widely used in peritoneal dialysis (PD) patients, yet controversy exists about their impact on residual kidney function.

OBJECTIVES

This review aimed to evaluate the benefits and harms of ACEis and ARBs for preserving residual kidney function in PD patients.

SEARCH METHODS

The Cochrane Renal Group's specialised register, Cochrane Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE (OvidSP interface), Chinese Biomedical Literature Database (CBM), China National Knowledge Infrastructure (CNKI) and other resources were searched by applying a prespecified comprehensive search strategy. Date of last search: 01 May 2014.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs comparing ACEis or ARBs with placebo, other antihypertensive drugs or each other in PD patients were included.

DATA COLLECTION AND ANALYSIS

Screening, selection, data extraction and quality assessments for each retrieved article were carried out by two authors using standardised forms. Authors were contacted when published data were incomplete. Statistical analyses were performed using the random effects model and results expressed as risk ratio (RR) with 95% confidence intervals (CI). Heterogeneity among studies was explored using the Cochran Q statistic and the I² test, subgroup analyses and random effects meta-regression.

MAIN RESULTS

Six open-label studies (257 patients) were identified. One study compared ACEi with other antihypertensive drugs, three compared ARBs with other antihypertensive drugs, and two studies compared an ARB with an ACEi. Long-term use (≥ 12 months) of an ARB showed significantly benefit of preserving residual kidney function in continuous ambulatory PD (CAPD) patients (MD 1.11 mL/min/1.73 m², 95% CI 0.38 to 1.83), although there was no significant benefit when an ARB were used short-term (≤ six months). One study showed that compared with other antihypertensive drugs, long-term use (12 months) of the ACEi ramipril showed a significant reduction in the decline of residual kidney function in patients on CAPD (MD -0.93 mL/min/1.73m², 95% CI -0.75 to -0.11), and delayed the progression to complete anuria (RR 0.64, 95% CI 0.41 to 0.99). There was no significant difference in serum potassium, urinary protein excretion, Kt/V, weekly creatinine clearance and blood pressure for ARBs versus other antihypertensive drugs. Compared with other antihypertensive drugs, ramipril showed no difference in mortality and cardiovascular events. Compared with an ACEi, ARBs did not show any difference in residual kidney function.The selection bias assessment was low in four studies and unclear in two. Five studies were open-label; however the primary outcome (residual kidney function) was obtained objectively from laboratory tests, and were not likely to be influenced by the lack of blinding. Reporting bias was unclear in all six studies.

AUTHORS' CONCLUSIONS

Compared with other antihypertensive drugs, long-term use (≥ 12 months) of ACEis or ARBs showed additional benefits of preserving residual kidney function in CAPD patients. There was no significant difference on residual kidney function preservation between ARBs and ACEis. However, limited by the small number of RCTs enrolling small number of participants, there is currently insufficient evidence to support the use of an ACEi or an ARB as first line antihypertensive therapy in PD patients.

Rapid Solute Transport in the Peritoneum: Physiologic and Clinical Consequences

This review focuses on the physiologic and clinical consequences of rapid solute transport in the peritoneum. The concept, the current understanding of related factors, and the possible causes implicated in rapid solute transport are discussed first. Then, the consequences, with particular emphasis on mortality, are highlighted. Finally, based on recent advances and clinical studies, some strategies for the treatment of fast peritoneal transport are reviewed.

Lercanidipine-Induced Chyloperitoneum in Patients on Peritoneal Dialysis

Objective

Lercanidipine is a lipophilic calcium channel blocker and a widely used antihypertensive agent. However, it can cause chyloperitoneum in patients receiving peritoneal dialysis (PD). The incidence, pathophysiology, and clinical impact of these adverse events are not known.

Design

Retrospective study.

Method

Patients were screened for use of antihypertensive agents. Those that had taken lercanidipine were identified and dialysate cholesterol (Chol) and triglyceride (TG) levels were checked. Serum levels were taken from the routine biochemistry record closest to the time of the dialysate levels. Dialysate Chol and TG from patients on other antihypertensives and with matched serum lipid profiles were compared.

Patients

14 of 222 patients had taken lercanidipine during February 2005 to January 2006, accounting for 12% of all patients on calcium channel blockers in our PD center.

Results

Of 14 patients prescribed lercanidipine, 8 (57%) developed chyloperitoneum. None had peritonitis and the dialysate was clear under microscopic examination. Mean dialysate TG was 128.4 ± 133.0 mg/dL and mean dialysate Chol was 18.2 ± 24.9 mg/dL in patients that developed chyloperitoneum. These patients were also noted to have higher blood TG and Chol than patients that did not develop chyloperitoneum. In contrast, patients on other antihypertensive agents with matched blood TG and Chol levels had low dialysate TG levels and zero dialysate Chol.

Conclusion

Lercanidipine frequently causes chyloperitoneum in Taiwanese PD patients. The risk of developing this adverse event seems to be related to the blood lipid profile. The mechanism of this phenomenon is worthy of further investigation.

Peritoneal dialysis, membranes and beyond

PURPOSE OF REVIEW

The peritoneal membrane provides the interface between dialysate fluid and blood for peritoneal dialysis patients. Functional properties of the peritoneal membrane have important clinical implications. This review will outline recent observations concerning structural changes in the peritoneal membrane and the impact on function and clinical outcomes.

RECENT FINDINGS

Peritoneal membrane function - solute transport and ultrafiltration - is a complex process involving new blood vessel growth along with changes in the nature of blood vessels and the interstitial environment of these vessels. Advanced glycation end-products produced by reactive oxygen species in the dialysis fluid have been identified as an agent of tissue fibrosis. Nitric oxide and IL-6 also have important roles in peritoneal membrane injury. Gene polymorphisms associated with peritoneal membrane function have been identified. As the mechanisms of peritoneal membrane injury become better elucidated, targeted therapies are being developed. The role of biocompatible and nonglucose dialysis fluids needs to be further defined.

SUMMARY

The peritoneal membrane is the lifeline for peritoneal dialysis patients. Our understanding of mechanisms of injury and functional responses continues to expand and will hopefully lead to therapies to improve the clinical outcomes for peritoneal dialysis patients.