Quantification of the risk and predictors of hyperkalemia in patients with left ventricular dysfunction: a retrospective analysis of the Studies of Left Ventricular Dysfunction (SOLVD) trials

Frequency and predictors of hyperkalemia in the heart failure outpatient clinic

Objectives: Hyperkalemia is a common and life-threatening condition affecting heart failure (HF) patients. This study aims to show the frequency of hyperkalemia and related factors in the HF outpatient clinic in real world data. Methods: 1146 patients monitored in the HF outpatient clinic with left ventricular ejection fraction ≤ 40% and potassium level ≥ 3.5 mmol/L were included in the study. Results: The median potassium value of the patients was 4.6 [IQR, 4.3-5] mmol/L. It was evaluated in three groups as 3.5-5 mmol/L (normokalaemia), 5.1-5.5 mmol/L (mild hyperkalemia), and ≥ 5.5 mmol/L (moderate to severe hyperkalemia) according to baseline potassium levels. 14.5% of patients had mild hyperkalemia and 7.1% had moderate to severe hyperkalemia. Patients with a potassium value of > 5 mmol/L made up 21.6%. The estimated glomerular filtration rate (eGFR) (OR: 0.968, 95% CI: 0.959-0.977, p

Adverse Effects of Medications on Micronutrient Status: From Evidence to Guidelines

Recent dietary reference intake workshops focusing on nutrient requirements in chronic disease populations have called attention to the potential adverse effects of chronic medication use on micronutrient status. Although this topic is mostly ill defined in the literature, several noteworthy drug-nutrient interactions (DNIs) are of clinical and public health significance. The purpose of this narrative review is to showcase classic examples of DNIs and their impact on micronutrient status, including those related to antidiabetic, anticoagulant, antihypertensive, antirheumatic, and gastric acid-suppressing medications. Purported DNIs related to other drug families, while relevant and worthy of discussion, are not included. Unlike previous publications, this review is primarily focused on DNIs that have sufficient evidence supporting their inclusion in US Food and Drug Administration labeling materials and/or professional guidelines. While the evidence is compelling, more high-quality research is needed to establish clear and quantitative relationships between chronic medication use and micronutrient status. Expected final online publication date for the Annual Review of Nutrition, Volume 41 is September 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Hyperkalemia and management of renin-angiotensin-aldosterone system inhibitors in chronic heart failure with reduced ejection fraction: A systematic review

INTRODUCTION AND OBJECTIVES

Renin-angiotensin-aldosterone system inhibitors (RAASi) are the cornerstone of treatment of heart failure with reduced ejection fraction (HFrEF). RAASi optimization in real-life care is challenged by hyperkalemia, a potentially fatal adverse event, which can necessitate downtitration or discontinuation of RAASi and negatively impact survival in HFrEF. The literature on this problem is sparse. We performed a systematic review of studies on HFrEF to investigate the prevalence, incidence, and risk factors of hyperkalemia, RAASi prescription rates, frequency of RAASi downtitration or discontinuation due to hyperkalemia, and the potential negative effect of the latter on prognosis.

METHODS

We conducted a MEDLINE (PubMed) search including observational and interventional studies published between January 1987 and May 2018.

RESULTS

A total of 30 observational and 18 interventional studies were included in the review. The incidence of hyperkalemia reported was between 0% and 63% in observational studies and was between 0% and 30% in clinical trials. Risk factors for hyperkalemia included RAASi prescription, older age, diabetes, and chronic kidney disease. In real-life studies, RAASi were downtitrated or discontinued in 3-22% of HFrEF patients; hyperkalemia was the reported cause in 5% of cases. No reports were found on the impact on prognosis of RAASi downtitration or discontinuation due to hyperkalemia.

CONCLUSIONS

Hyperkalemia and RAASi downtitration or discontinuation are frequent, particularly in real-life HFrEF studies. Further research is needed to clarify the role of RAASi downtitration or discontinuation due to hyperkalemia and to assess its long-term prognostic impact in HFrEF patients.

Cardiorenal Syndrome: Classification, Pathophysiology, Diagnosis, and Treatment Strategies: A Scientific Statement From the American Heart Association

Cardiorenal syndrome encompasses a spectrum of disorders involving both the heart and kidneys in which acute or chronic dysfunction in 1 organ may induce acute or chronic dysfunction in the other organ. It represents the confluence of heart-kidney interactions across several interfaces. These include the hemodynamic cross-talk between the failing heart and the response of the kidneys and vice versa, as well as alterations in neurohormonal markers and inflammatory molecular signatures characteristic of its clinical phenotypes. The mission of this scientific statement is to describe the epidemiology and pathogenesis of cardiorenal syndrome in the context of the continuously evolving nature of its clinicopathological description over the past decade. It also describes diagnostic and therapeutic strategies applicable to cardiorenal syndrome, summarizes cardiac-kidney interactions in special populations such as patients with diabetes mellitus and kidney transplant recipients, and emphasizes the role of palliative care in patients with cardiorenal syndrome. Finally, it outlines the need for a cardiorenal education track that will guide future cardiorenal trials and integrate the clinical and research needs of this important field in the future.

Mineralcorticoid Receptor Antagonist Withdrawal for Hyperkalemia and Mortality in Patients with Heart Failure

Background: Hyperkalemia is one of the most frequent side effects related to renin-angiotensin-aldosterone system (RAAS) inhibition, and can influence optimization of heart failure (HF) therapy. Aim: To evaluate the occurrence of hyperkalemia in a series of outpatients with chronic HF and its relationship with RAAS inhibitor therapy. Method: We evaluated consecutive outpatients with HF and a reduced left ventricular ejection fraction. The incidence of hyperkalemia and consequent changes in RAAS inhibitor therapy were evaluated for each patient. Results: A history of hyperkalemia or at least 1 episode of hyperkalemia during follow-up was observed in 104 of 351 patients. Hyperkalemia mainly influenced mineralocorticoid receptor antagonist (MRA) therapy and, among patients with hyperkalemia, not taking MRA was associated with a greater risk of death on univariate analysis (HR = 6.39; 95% CI 2.76–14.79, p < 0.001) and multivariate analysis (HR = 5.24; 95% CI 1.87–14.72, p = 0.002) after correction for age, ischemic cardiomyopathy, diabetes, systolic arterial pressure, New York Heart Association class 3, left ventricular ejection fraction, presence of hyponatremia, glomerular filtration rate calculated by the EPI formula, and presence of N-terminal pro-B-type natriuretic peptide >1,000 pg/mL. Conclusion: The occurrence of hyperkalemia is common among outpatients with HF and it is the main cause of MRA withdrawal, which is associated with a worse prognosis. In this setting, the possibility of managing hyperkalemia using new classes of drugs could allow continuation of MRA therapy.

Hyperkalaemia: aetiology, epidemiology, and clinical significance

Disturbances in the potassium homeostasis are common among patients with heart failure (HF) and negatively affect clinical outcome. Patients with HF have a higher prevalence of common risk factors related to hyperkalaemia, including diabetes mellitus, hypertension, and chronic kidney disease. Furthermore, the use of renin-angiotensin-aldosterone system (RAAS) inhibitors, is an important risk factor for developing hyperkalaemia. The association between hyperkalaemia and mortality is not unequivocal, depends on the study type (trial vs. real-world setting) and is often confounded. More importantly, hyperkalaemia is an important cause of discontinuation or failure to uptitrate to guideline recommended dosages of RAAS inhibitors, which in turn may negatively impact clinical outcomes. The goal of this review is to discuss the epidemiology, aetiology, and clinical consequences of potassium disturbances in HF.

The use of diuretics in heart failure with congestion - a position statement from the Heart Failure Association of the European Society of Cardiology

The vast majority of acute heart failure episodes are characterized by increasing symptoms and signs of congestion with volume overload. The goal of therapy in those patients is the relief of congestion through achieving a state of euvolaemia, mainly through the use of diuretic therapy. The appropriate use of diuretics however remains challenging, especially when worsening renal function, diuretic resistance and electrolyte disturbances occur. This position paper focuses on the use of diuretics in heart failure with congestion. The manuscript addresses frequently encountered challenges, such as (i) evaluation of congestion and clinical euvolaemia, (ii) assessment of diuretic response/resistance in the treatment of acute heart failure, (iii) an approach towards stepped pharmacologic diuretic strategies, based upon diuretic response, and (iv) management of common electrolyte disturbances. Recommendations are made in line with available guidelines, evidence and expert opinion.

Low body mass index is a risk factor for hyperkalaemia associated with angiotensin converting enzyme inhibitors and angiotensin II receptor blockers treatments

WHAT IS KNOWN AND OBJECTIVE

Angiotensin converting enzyme inhibitors (ACEI) and angiotensin II receptor blockers (ARB) represent the cornerstones of hypertension and congestive heart failure treatment. Risk factors for hyperkalaemia associated with ACEI and ARB are chronic kidney disease and concomitant medications which increase serum potassium level. Body mass index (BMI) also affects pharmacokinetics of ACEI and ARB and potassium disposition. We evaluated the relationship between BMI and hyperkalaemia associated with ACEI and ARB treatments.

METHODS

Study design is a retrospective case-control analysis. Patients who had been prescribed ACEI or ARB between June 2015 and June 2017 at Tokyo Women's Medical University, Medical Center East, were included. Patient clinical background was collected from medical records. Hyperkalaemia was defined as serum potassium above 5.5 meq/L. The concomitant use of ACEI and ARB, aldosterone antagonists, direct renin inhibitor, sulfamethoxazole-trimethoprim and non-steroidal anti-inflammatory drugs (NSAIDs) was regarded as hyperkalaemia-inducing medications. The relationship between BMI and hyperkalaemia associated with ACEI and ARB treatments was assessed using multivariable logistic regression analysis.

RESULTS AND DISCUSSION

The study included 2987 patients aged 70.1 ± 12.9 years, 61.0% were men, and BMI was 23.8 ± 4.4 kg/m² . The incidence of hyperkalaemia was 7.8%. Multivariable logistic regression analysis revealed that age >65 years, low BMI, diabetes, history of treatment for hyperkalaemia, serum sodium <135 meq/L, eGFR <30 mL/min/1.73m² and the concomitant use of hyperkalaemia-inducing medications were independent risk factors for hyperkalaemia associated with ACEI and ARB.

WHAT IS NEW AND CONCLUSION

This study demonstrated that BMI provides useful information for the identification of potential risk for hyperkalaemia associated with ACEI and ARB treatments.

Pharmacologic Approaches to Electrolyte Abnormalities in Heart Failure

Electrolyte abnormalities are common in heart failure and can arise from a variety of etiologies. Neurohormonal activation from ventricular dysfunction, renal dysfunction, and heart failure medications can perturb electrolyte homeostasis which impact both heart failure-related morbidity and mortality. These include disturbances in serum sodium, chloride, acid-base, and potassium homeostasis. Pharmacological treatments differ for each electrolyte abnormality and vary from older, established treatments like the vaptans or acetazolamide, to experimental or theoretical treatments like hypertonic saline or urea, or to newer, novel agents like the potassium binders: patiromer and zirconium cyclosilicate. Pharmacologic approaches range from limiting electrolyte intake or directly repleting the electrolyte, to blocking or promoting their resorption, and to neurohormonal antagonism. Because of the prevalence and clinical impact of electrolyte abnormalities, understanding both the older and newer therapeutic options is and will continue to be necessity for the management of heart failure.

Adherence to guidelines for creatinine and potassium monitoring and discontinuation following renin-angiotensin system blockade: a UK general practice-based cohort study

OBJECTIVES

To examine adherence to serum creatinine and potassium monitoring and discontinuation guidelines following initiation of treatment with ACE inhibitors (ACEI) or angiotensin receptor blockers (ARBs); and whether high-risk patients are monitored.

DESIGN

A general practice-based cohort study using electronic health records from the UK Clinical Practice Research Datalink and Hospital Episode Statistics.

SETTING

UK primary care, 2004-2014.

SUBJECTS

223 814 new ACEI/ARB users.

MAIN OUTCOME MEASURES

Proportion of patients with renal function monitoring before and after ACEI/ARB initiation; creatinine increase ≥30% or potassium levels >6 mmol/L at first follow-up monitoring; and treatment discontinuation after such changes. Using logistic regression models, we also examined patient characteristics associated with these biochemical changes, and with follow-up monitoring within the guideline recommendation of 2 weeks after treatment initiation.

RESULTS

10% of patients had neither baseline nor follow-up monitoring of creatinine within 12 months before and 2 months after initiation of an ACEI/ARB, 28% had monitoring only at baseline, 15% only at follow-up, and 47% both at baseline and follow-up. The median period between the most recent baseline monitoring and drug initiation was 40 days (IQR 12-125 days). 34% of patients had baseline creatinine monitoring within 1 month before initiating therapy, but <10% also had the guideline-recommended follow-up test recorded within 2 weeks. Among patients experiencing a creatinine increase ≥30% (n=567, 1.2%) or potassium level >6 mmol/L (n=191, 0.4%), 80% continued treatment. Although patients with prior myocardial infarction, hypertension or baseline potassium >5 mmol/L were at high risk of ≥30% increase in creatinine after ACEI/ARB initiation, there was no evidence that they were more frequently monitored.

CONCLUSIONS

Only one-tenth of patients initiating ACEI/ARB therapy receive the guideline-recommended creatinine monitoring. Moreover, the vast majority of the patients fulfilling postinitiation discontinuation criteria for creatinine and potassium increases continue on treatment.

Dilemmas in the Dosing of Heart Failure Drugs: Titrating Diuretics in Chronic Heart Failure

Despite advances in medical therapy over the past few decades, the incidence of heart failure hospitalisation continues to rise. Diuretics are the most common therapy used to treat heart failure as they relieve congestion. However, there is a lack of guidance on how to best use these medications. Guidelines support the use of diuretics at the lowest clinically effective dose but do not specify a diuretic strategy beyond that. Here we review the diuretics available for treatment, potential mechanisms of diuretic resistance and ways to address this in the ambulatory setting, and review tools that have been developed to help guide diuretic use in the treatment of chronic heart failure.

Calibrating the impact of dual RAAS blockade on the heart and the kidney - balancing risks and benefits

Overactivity of the renin-angiotensin-aldosterone system (RAAS) plays a key role in the pathophysiology of heart failure (HF) and chronic kidney disease (CKD). RAAS antagonists can significantly improve clinical outcomes, but monotherapy blocks but one step of the RAAS and can be bypassed through compensatory mechanisms. Providing more complete RAAS blockade by deploying drugs with complementary actions seemed logical - hence the practice of using dual (or triple) RAAS inhibitors. However, RAAS antagonists also exhibit dose-limiting side effects, including acute kidney injury, hyperkalaemia and hypotension, which blunt their overall effectiveness. Despite achieving better RAAS blockade, several trials failed to show clinical outcome improvements. Patients with concomitant CKD and HF (cardiorenal syndrome) are at the greatest risk of these adverse events and therefore the least able to benefit, yet they also have the worst prognosis. This paradox, where those most in need have fewest therapeutic options, poses three questions which are the focus of this review: whether (i) novel therapies that prevent adverse effects can restore therapeutic benefits to patients who would otherwise be RAAS-therapy intolerant, (ii) there are any validated alternatives to their use and (iii) newer approaches to the detection of fluid congestion are ready for implementation.

Impact of hyperkalaemia definition on incidence assessment: implications for epidemiological research based on a large cohort study in newly diagnosed heart failure patients in primary care

Background

Various definitions of hyperkalaemia have been used in clinical research, and data from routine clinical practice on its incidence are sparse. We aimed to establish the incidence of hyperkalaemia in patients with newly diagnosed heart failure in the UK general population using different definitions for the condition.

Methods

We conducted a large retrospective cohort study using data from The Health Improvement Network primary care database. Patients with newly diagnosed heart failure (N = 19,194) were identified and followed until the first occurrence of hyperkalaemia. Different serum potassium (K⁺) thresholds were evaluated as possible definitions for hyperkalaemia, and incidence rates (IRs) calculated using a final operational definition both overall and among patient sub-groups.

Results

IRs of hyperkalaemia ranged from 0.92–7.93 per 100 person-years according to the definition. Based on considerable differences in the serum K⁺ normal range used between practices, 2176 (11.3 %) individuals were identified with a record of hyperkalaemia using our operational definition of a proportional increase of ≥10 % above the upper bound of the normal range: IR 2.90 per 100 person-years (95 % CI 2.78–3.02) over a mean follow-up of 3.91 years. Incidence rates were higher in older patients, and in those with diabetes or renal impairment.

Conclusions

Hyperkalaemia is a common finding in heart failure patients in primary care, but its incidence can vary nearly ten-fold depending on its definition. Since assessment of hyperkalaemia risk is essential for therapeutic decision making in heart failure patients, this finding warrants consideration in future epidemiological studies.

Effect of fermented milk product containing lactotripeptides and plant sterol esters on haemodynamics in subjects with the metabolic syndrome – a randomised, double-blind, placebo-controlled study

We investigated the effects of fermented milk product containing isoleucine–proline–proline, valine–proline–proline and plant sterol esters (Pse) on plasma lipids, blood pressure (BP) and its determinants systemic vascular resistance and cardiac output. In a randomised, double-blind, placebo-controlled study, 104 subjects with the metabolic syndrome (MetS) were allocated to three groups in order to receive fermented milk product containing (1) 5 mg/d lactotripeptides (LTP) and 2 g/d plant sterols; (2) 25 mg/d LTP and 2 g/d plant sterols; (3) placebo for 12 weeks. Plasma lipids and home BP were monitored. Haemodynamics were examined in a laboratory using radial pulse wave analysis and whole-body impedance cardiography in the supine position and during orthostatic challenge. There were no differences between the effects of the two treatments and placebo on the measurements of BP at home or on BP, systemic vascular resistance index and cardiac index in the laboratory, neither in the supine nor in the upright position. The changes in plasma LDL-cholesterol concentration were − 0·1 (95 % CI − 0·3, 0·1 and − 0·3, 0·0) mmol/l in the 5 and 25 mg/d LTP groups, respectively, and +0·1 (95 % CI − 0·1, 0·3) mmol/l during placebo (P= 0·024). Both at baseline and at week 12, the increase in systemic vascular resistance during head-up tilt was lower in the 25 mg/d LTP group than in the 5 mg/d LTP group (P< 0·01), showing persistent differences in cardiovascular regulation between these groups. In subjects with the MetS, intake of LTP and Pse in fermented milk product showed a lipid-lowering effect of borderline significance, while no antihypertensive effect was observed at home or in the laboratory.

Risk factors for hyperkalaemia in a cohort of patients with newly diagnosed heart failure: a nested case-control study in UK general practice

AIMS

The aim of this study was to identify risk factors for hyperkalaemia in a cohort of patients with newly diagnosed heart failure in the UK.

METHODS AND RESULTS

A nested case-control study was conducted using data from The Health Improvement Network primary care database. A cohort of 19 194 patients aged 1-89 years between January 2000 and December 2005 with newly diagnosed heart failure was followed up and cases of hyperkalaemia identified. Cases were frequency matched to controls by age, sex, and calendar year, and information on demographics, co-morbidities, co-medications, and lifestyle factors was extracted from the database. Using unconditional logistic regression models, odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to identify potential risk factors. In total, 2176 hyperkalaemia cases were identified over a mean follow-up of 3.9 years. Significant risk factors for hyperkalaemia were: renal failure (OR 3.81; 95% CI 3.29-4.42), type II diabetes (OR 1.52; 95% CI 1.31-1.75), valvular heart disease (OR 1.28; 95% CI 1.06-1.54), and current use of potassium-sparing diuretics (OR 3.01; 95% CI 2.61-3.48), ACE inhibitors (OR 1.70; 95% CI 1.41-2.04), trimethoprim (OR 2.82; 95% CI 1.88-4.23), non-steroidal anti-inflammatory drugs (OR 1.41; 95% CI 1.11-1.79), and several drug combinations. The risk was highest within the first month of medication use and decreased thereafter.

CONCLUSION

Our findings may help to better identify patients with heart failure most likely to benefit from careful monitoring of serum potassium levels. Particular vigilance is needed during the start of treatment with certain medications.

Cost effectiveness of a pharmacist-led information technology intervention for reducing rates of clinically important errors in medicines management in general practices (PINCER)

BACKGROUND AND OBJECTIVE

We recently showed that a pharmacist-led information technology-based intervention (PINCER) was significantly more effective in reducing medication errors in general practices than providing simple feedback on errors, with cost per error avoided at £79 (US$131). We aimed to estimate cost effectiveness of the PINCER intervention by combining effectiveness in error reduction and intervention costs with the effect of the individual errors on patient outcomes and healthcare costs, to estimate the effect on costs and QALYs.

METHODS

We developed Markov models for each of six medication errors targeted by PINCER. Clinical event probability, treatment pathway, resource use and costs were extracted from literature and costing tariffs. A composite probabilistic model combined patient-level error models with practice-level error rates and intervention costs from the trial. Cost per extra QALY and cost-effectiveness acceptability curves were generated from the perspective of NHS England, with a 5-year time horizon.

RESULTS

The PINCER intervention generated £2,679 less cost and 0.81 more QALYs per practice [incremental cost-effectiveness ratio (ICER): -£3,037 per QALY] in the deterministic analysis. In the probabilistic analysis, PINCER generated 0.001 extra QALYs per practice compared with simple feedback, at £4.20 less per practice. Despite this extremely small set of differences in costs and outcomes, PINCER dominated simple feedback with a mean ICER of -£3,936 (standard error £2,970). At a ceiling 'willingness-to-pay' of £20,000/QALY, PINCER reaches 59 % probability of being cost effective.

CONCLUSIONS

PINCER produced marginal health gain at slightly reduced overall cost. Results are uncertain due to the poor quality of data to inform the effect of avoiding errors.

Heart failure in patients with chronic kidney disease: a systematic integrative review

Introduction. Heart failure (HF) is highly prevalent in patients with chronic kidney disease (CKD) and end-stage renal disease (ESRD) and is strongly associated with mortality in these patients. However, the treatment of HF in this population is largely unclear. Study Design. We conducted a systematic integrative review of the literature to assess the current evidence of HF treatment in CKD patients, searching electronic databases in April 2014. Synthesis used narrative methods. Setting and Population. We focused on adults with a primary diagnosis of CKD and HF. Selection Criteria for Studies. We included studies of any design, quantitative or qualitative. Interventions. HF treatment was defined as any formal means taken to improve the symptoms of HF and/or the heart structure and function abnormalities. Outcomes. Measures of all kinds were considered of interest. Results. Of 1,439 results returned by database searches, 79 articles met inclusion criteria. A further 23 relevant articles were identified by hand searching. Conclusions. Control of fluid overload, the use of beta-blockers and angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, and optimization of dialysis appear to be the most important methods to treat HF in CKD and ESRD patients. Aldosterone antagonists and digitalis glycosides may additionally be considered; however, their use is associated with significant risks. The role of anemia correction, control of CKD-mineral and bone disorder, and cardiac resynchronization therapy are also discussed.

Monitoring and adverse events in relation to ACE inhibitor/angiotensin receptor blocker initiation in people with diabetes in general practice: a population database study

BACKGROUND AND AIM

To determine whether angiotensin-converting enzyme inhibitor/angiotensin receptor blocker (ACEI/ARB) initiation in people with diabetes is monitored as recommended by recent guidelines and the incidence of associated adverse renal events.

DESIGN

Retrospective population database analysis of 4056 people in Tayside, Scotland with type 2 diabetes prescribed an ACEI/ARB between 1 January 2005 and 31 December 2009.

METHOD

Measurement of urea and electrolytes (U&Es) before and after ACEI/ARB initiation and renal adverse events; defined as a ≥30% rise in serum creatinine and post-initiation potassium of ≥5.6 mmol/L. Associations of adverse events with patient demographics or co-prescription of drugs with known renal effects were examined.

RESULTS

Overall, 89% of initiations were with an ACE inhibitor. A total of 18.84% (CI 95% 18.82-18.86) of patients initiating ACE inhibitor or ARB had U&Es measured in the 90 days before initiation and within 5-14 days after initiation. Only 1.7% of patients had an adverse renal event. Patients prescribed with an ARB were less likely to be monitored than those prescribed with an ACE inhibitor, but no less likely to suffer harm.

CONCLUSIONS

Current clinical practice of biochemical monitoring of ACE inhibitor/ARB is poor, but adverse events are rare. Further studies with serial U&Es are needed to establish the critical time window for adverse renal events and evaluate whether intensive biochemical monitoring recommended is required in low-risk groups.

Onset time of hyperkalaemia after angiotensin receptor blocker initiation: when should we start serum potassium monitoring?

WHAT IS KNOWN AND OBJECTIVE

Angiotensin receptor blockers (ARBs) frequently induce hyperkalaemia in high-risk patients. Early detection of hyperkalaemia can reduce the subsequent harmful effects. This study was performed to examine the onset time of hyperkalaemia after ARB therapy.

METHODS

We carried out a retrospective analysis to determine the onset time of hyperkalaemia (serum potassium >5·5 mm) among hospitalized patients newly starting ARB therapy between 2004 and 2012, in a tertiary teaching hospital. Predefined possible risk factors and concomitant medications were evaluated.

RESULTS AND DISCUSSION

During the 97-month study period, a total of 4267 hospitalized patients started ARBs as new drugs and 225 patients showed hyperkalaemia. A significantly increased risk of hyperkalaemia was detected among patients with a high baseline potassium [odds ratio (OR) 6·0] and those who took non-potassium-sparing diuretics (OR 2·2) or potassium supplements (OR 1·6). A high glomerular filtration rate (GFR) was associated with a lower risk of hyperkalaemia (OR 0·992). Fifty-two percentage of hyperkalaemic events occurred within the first week after initiation of ARB therapy. The highest frequency of hyperkalaemia occurred on the first day after initiation of ARBs. Hyperkalaemia occurred earlier in patients with a high baseline serum potassium level, reduced GFR, diabetes and in those without heart failure.

WHAT IS NEW AND CONCLUSION

Hyperkalaemia occurs most frequently at the beginning of ARB therapy in hospitalized patients. Monitoring of serum potassium and estimated GFR after initiation of ARBs should be started within a few days or not later than 1 week, especially in patients with risk factors.

Risk of hyperkalemia in patients with moderate chronic kidney disease initiating angiotensin converting enzyme inhibitors or angiotensin receptor blockers: a randomized study

Background

Angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers are renoprotective but both may increase serum potassium concentrations in patients with chronic kidney disease (CKD). The proportion of affected patients, the optimum follow-up period and whether there are differences between drugs in the development of this complication remain to be ascertained.

Methods

In a randomized, double-blind, phase IV, controlled, crossover study we recruited 30 patients with stage 3 CKD under restrictive eligibility criteria and strict dietary control. With the exception of withdrawals, each patient was treated with olmesartan and enalapril separately for 3 months each, with a 1-week wash-out period between treatments. Patients were clinically assessed on 10 occasions via measurements of serum and urine samples. We used the Cochran–Mantel–Haenszel statistics for comparison of categorical data between groups. Comparisons were also made using independent two-sample t-tests and Welch’s t-test. Analysis of variance (ANOVA) was performed when necessary. We used either a Mann–Whitney or Kruskal-Wallis test if the distribution was not normal or the variance not homogeneous.

Results

Enalapril and olmesartan increased serum potassium levels similarly (0.3 mmol/L and 0.24 mmol/L respectively). The percentage of patients presenting hyperkalemia higher than 5 mmol/L did not differ between treatments: 37% for olmesartan and 40% for enalapril. The mean e-GFR ranged 46.3 to 48.59 ml/mint/1.73 m² in those treated with olmesartan and 46.8 to 48.3 ml/mint/1.73 m² in those with enalapril and remained unchanged at the end of the study. The decreases in microalbuminuria were also similar (23% in olmesartan and 29% in enalapril patients) in the 4 weeks time point. The percentage of patients presenting hyperkalemia, even after a two month period, did not differ between treatments. There were no appreciable changes in sodium and potassium urinary excretion.

Conclusions

Disturbances in potassium balance upon treatment with either olmesartan or enalapril are frequent and without differences between groups. The follow-up of these patients should include control of potassium levels, at least after the first week and the first and second month after initiating treatment.

Trial registration

The trial EudraCT “2008-002191-98”.

The safety and tolerability of spironolactone in patients with mild to moderate chronic kidney disease

AIM

Mineralocorticoid receptor blockade (MRBs) in combination with angiotensin converting enzyme (ACE) inhibitors and angiotensin-II receptor blockade (ARBs) improve prognostic markers of cardiovascular and renal disease in early stage chronic kidney disease (CKD). Concerns relating to the safety and tolerability of MRBs in CKD may limit their use in a non clinical trial setting. METHODS In the Chronic Renal Impairment in Birmingham II study, 115 patients with non-diabetic early stage CKD (eGFR 30-89ml/min/1.73m(2) ) received 25mg daily of spironolactone for 4 weeks before randomization to continuing treatment or placebo for a further 36 weeks. All patients were on ACE inhibitors and/or ARB therapy. Potassium and renal function were checked at weeks 1, 2, 4, 8, 16, 28 and 40. The incidence of hyperkalaemia, significant renal dysfunction (reduction eGFR ≥25%) and adverse effects was assessed.

RESULTS

After 40 weeks of treatment the incidence of serious hyperkalaemia (K(+) ≥6.0mmol/L) was <1%. A potassium 5.5-5.9mmol/L occurred on ≥1 occasion over follow-up in 11 patients (nine on spironolactone) and was predicted by baseline potassium ≥5.0mmol/L and eGFR ≤45 ml/min/1.73m(2) . Over follow-up, three patients experienced significant renal dysfunction but no patients withdrew due to intolerance or side effects. Changes in potassium, eGFR and systolic blood pressure were most apparent in the first 4 eeks.

CONCLUSION

Spironolactone was well tolerated in selected patients with early stage CKD. Strict monitoring over the first month of treatment followed by standard surveillance as for ACE inhibitors and ARBs is suggested.

Drug-induced life-threatening potassium disturbances detected by a pharmacovigilance program from laboratory signals

PURPOSE

Detection and reporting of drug-induced life-threatening potassium disturbances and the study of associated factors under a Pharmacovigilance Program using Laboratory Signals at a Hospital (PPLSH) during a 2-year period.

METHODS

All serum potassium levels <2 mmol/l or >7 mmol/l detected at admission to the hospital, including those of patients who died in the emergency ward or during hospitalization, were monitored prospectively from January 2009 through to December 2010. The incidence rate of each etiology of potassium disturbances was calculated. Factors associated with drug-induced potassium disturbances were detected using a multiple logistic regression model.

RESULTS

The incidence of true life-threatening drug-induced hyper- and hypokalemia events was 3 and 4.32 (Poisson 95 % confidence interval 1.62-10.24), respectively, per 10,000 admissions. Of the severe potassium disturbances, 32.3 % were drug-induced, and 23 % were lethal. We identified previously undescribed pharmacological causes of hyperkalemia (risedronate, doxazosin) and hypokalemia (acyclovir, teicoplanin, cefepime, meropenem, dexketoprofen colistimethate). Significant predictor factors associated with drug-induced hyperkalemia were the use of polypharmacy (>5 drugs), age (>74 years), sex (female) and kidney disease (glomerular filtration rate <60 ml/min) with the presence of ≥4 comorbid conditions. The only predictor of drug-induced hypokalemia was the use of >5 drugs. The triggering factor associated with drug-induced hyperkalemia and hypokalemia was azotemia and hypoalbuminemia, respectively.

CONCLUSIONS

Drug-induced life-threatening potassium disturbances remain a relevant problem. Potential strategies for prevention are to avoid polypharmacy, early discontinuation of treatment of drugs causing hyperkalemia or nephrotoxicity in cases of various clinical situations (cardiac descompensation, infection, hypovolemia) or obstructive causes, and insistence on albumin control during hospitalization.

Predictors of hyperkalemia and death in patients with cardiac and renal disease

Predictors of hyperkalemia in patients with cardiovascular disease (CVD; defined as patients with hypertension and heart failure) and associated chronic kidney disease (CKD) are not well established. The aim of this study was to ascertain risk factors of hyperkalemia (defined as serum potassium concentration >5.0 mEq/L) and associated all-cause mortality in patients with CVD treated with antihypertensive drugs that impair potassium homeostasis. In a retrospective analysis using a logistic regression model, risk factors for hyperkalemia and all-cause mortality were analyzed in 15,803 patients with CVD treated with antihypertensive drugs. The mean estimated glomerular filtration rate and mean serum potassium concentration were 55.55 ml/min/1.73 m(2) and 4.06 mEq/L, respectively. Hyperkalemia was observed in 24.5% of study patients and 1.7% of total hospital admissions. Compared to patients with normokalemia, those with hyperkalemia had a higher percentage of death (6.25% vs 2.92%, p = 0.0001) and admissions (7.80% vs 5.04%, p = 0.0001). Predictors of hyperkalemia were CKD stage (odds ratio [OR] 2.14, 95% confidence interval [CI] 2.02 to 2.28), diabetes mellitus (OR 1.59, 95% CI 1.47 to 1.72), coronary artery disease (OR 1.32, 95% CI 1.21 to 1.43), and peripheral vascular disease (OR 1.55, 95% CI 1.36 to 1.77). Predictors of all-cause mortality were CKD stage (OR 1.26, 95% CI 1.12 to 1.43), hyperkalemic event (OR 1.56, 95% CI 1.30 to 1.88), age (OR 1.04, 95% CI 1.03 to 1.05), and hospitalization (OR 1.04, 95% CI 1.04 to 1.05). In conclusion, hyperkalemia is encountered frequently in patients with established CVD who are taking antihypertensive drugs and is associated with increases in all-cause mortality and hospitalizations. Advanced CKD, diabetes mellitus, coronary artery disease, and peripheral vascular disease are independent predictors of hyperkalemia.

Frequency and predictors of hyperkalemia in patients ≥60 years of age with heart failure undergoing intense medical therapy

Hyperkalemia is a concern in heart failure (HF), especially in older patients with co-morbidities. Previous studies addressing this issue have focused mainly on younger patients. This study was aimed at determining the frequency and predictors of hyperkalemia in older patients with HF undergoing intense medical therapy. Frequency and predictors of hyperkalemia were defined in patients (n = 566) participating in the Trial of Intensified versus Standard Medical Therapy in Elderly Patients with Congestive Heart Failure, in which patients ≥60 years of age were randomized to a standard versus an intensified N-terminal brain natriuretic peptide-guided HF therapy. During an 18-month follow-up 76 patients (13.4%) had hyperkalemia (≥5.5 mmol/L) and 28 (4.9%) had severe hyperkalemia (≥6.0 mmol/L). Higher baseline serum potassium (odds ratio [OR] 2.92 per mmol/L), baseline creatinine (OR 1.11 per 10 μmol/L), gout (OR 2.56), New York Heart Association (NYHA) class (compared to NYHA class II, IV OR 3.08), higher dosage of spironolactone at baseline (OR 1.20 per 12.5 mg/day), and higher dose changes of spironolactone (compared to no dose change: 12.5 mg, OR 1.45; 25 mg, OR 2.52; >25 mg, OR 3.24) were independent predictors for development of hyperkalemia (p <0.05 for all comparisons). In conclusion, hyperkalemia is common in patients ≥60 years of age with HF undergoing intense medical therapy. Risk is increased in patients treated with spironolactone, in addition to patient-specific risk factors such as chronic kidney disease, higher serum potassium, advanced NYHA class, and gout. Careful surveillance of serum potassium and cautious use of spironolactone in patients at risk may help to decrease the incidence of potentially hazardous complications caused by hyperkalemia.

Adherence to biochemical monitoring recommendations in patients starting with renin angiotensin system inhibitors: a retrospective cohort study in the Netherlands

BACKGROUND

Renin angiotensin system inhibitors (RASIs) are frequently involved in serious adverse events. These events principally occur in high-risk patients and often arise within the first days after treatment initiation; therefore, guidelines recommend biochemical monitoring within 3 weeks after the start of therapy with RASIs.

OBJECTIVE

The purpose of this study was to examine the level of biochemical monitoring directly after treatment initiation with RASIs in patients with different risk profiles and to study the attitudes of the physicians involved towards biochemical monitoring.

METHODS

We carried out a retrospective analysis of 202 patients who started RASI therapy in 2006 in Groesbeek, the Netherlands. We determined the rate of serum creatinine and potassium monitoring within 3 weeks after the start of therapy. In addition, we studied the intentions and attitudes towards biochemical monitoring during RASI therapy among 68 general practitioners and medical specialists by way of a brief questionnaire.

RESULTS

Serum creatinine and potassium monitoring after treatment initiation was performed in 34% and 28% of patients, respectively. Of all the patients, 29% had two or more additional risk factors for renal function deterioration. In these high-risk patients, creatinine was significantly less often monitored compared with low-risk patients (22% vs 39%). In contrast to these findings, the prescribing physicians claimed to check serum creatinine within 2 weeks after treatment initiation in 85% of their patients. Most of the prescribing physicians (88%) rated this monitoring as (very) important.

CONCLUSIONS

We demonstrated that, despite positive intentions of physicians, the biochemical monitoring recommendation in patients treated with RASIs is poorly met. In addition, serum creatinine monitoring was significantly less often performed in high-risk patients compared with low-risk patients.

Diabetes and drug-associated hyperkalemia: effect of potassium monitoring

BACKGROUND

Renin-angiotensin-aldosterone system (RAAS) inhibitors are associated with hyperkalemia, but there is little evidence demonstrating patients who receive potassium monitoring have a lower rate of hyperkalemia.

OBJECTIVE

To evaluate the association between potassium monitoring and serious hyperkalemia-associated adverse outcomes among patients with diabetes newly initiating RAAS inhibitor therapy.

DESIGN

Retrospective observational study.

PARTICIPANTS

Patients with diabetes without end-stage renal disease initiating RAAS inhibitor therapy between 2001 and 2006 at three integrated health care systems.

MEASUREMENTS

Potassium monitoring and first hyperkalemia-associated adverse event during the initial year of therapy. Hyperkalemia-associated adverse events included hospitalizations, emergency department visits or deaths within 24 h of hyperkalemia diagnosis and/or diagnostic potassium >or=6 mmol/l. Incidence rates were calculated in person-years (p-y). We used inverse probability propensity score weighting to adjust for differences between patients with and without monitoring; Poisson regression was used to obtain adjusted relative risks.

RESULTS

A total of 19,391 of 27,355 patients (71%) received potassium monitoring. Serious hyperkalemia-associated events occurred at an incidence rate of 10.2 per 1,000 p-y. Compared to patients without monitoring, adjusted relative risk of hyperkalemia-associated adverse events among all patients with monitoring was 0.50 (0.37, 0.66); in the subset of patients who also had chronic kidney disease (n = 2,176), adjusted relative risk was 0.29 (0.18, 0.46).

CONCLUSIONS

Patients prescribed RAAS inhibitors who have both diabetes and chronic kidney disease and receive potassium monitoring are less likely to experience a serious hyperkalemia-associated adverse event compared to similar patients who did not receive potassium monitoring. This evidence supports existing consensus-based guidelines.

Increasingly restrictive definitions of hyperkalemia outcomes in a database study: effect on incidence estimates

PURPOSE

To determine the incidence of hyperkalemia-associated adverse outcomes among ambulatory patients with diabetes newly initiating renin-angiotensin-aldosterone system (RAAS) inhibitor therapy and to examine to what extent increasingly restrictive definitions of hyperkalemia-associated outcomes influenced incidence estimates.

METHODS

Retrospective cohort study of 27 355 individuals with diabetes who were new users of RAAS inhibitors at three integrated healthcare systems.

RESULTS

Using the least restrictive definition of hyperkalemia-associated outcome, an ambulatory visit (AV), inpatient hospitalization (IP), or emergency department (ED) visit co-occurring within 7 days of coded hyperkalemia diagnosis and/or potassium concentration of > or =5.5 mmol/L, the incidence rate of hyperkalemia was 30.1 per 1000 person-years (p-y). Restricting to only IP or ED visits co-occurring within 24 hours of coded diagnosis and/or potassium > or =6 mmol/L, the incidence rate was 10.2 per 1000 p-y. When this latter definition was further restricted by removing available potassium laboratory values, the incidence rate declined to 9.5 per 1000 p-y.

CONCLUSIONS

Modifying the definition of hyperkalemia-associated outcome resulted in up to threefold differences in incidence rate estimates. Our results demonstrate the value of including potassium laboratory results and AVs in identifying hyperkalemia from electronic data. Comparing incidence estimates across published studies requires consideration of differences in outcome definitions.

Pharmacologic therapy in patients with chronic heart failure and chronic kidney disease: a complex issue

Chronic kidney disease is common in patients with chronic heart failure and has important clinical implications. The coexistence of these two syndromes is associated with a higher risk of adverse outcome and increases the difficulties of heart failure treatment because of the complex interplay between renal dysfunction and pharmacologic therapy. The underrepresentation of patients with chronic kidney disease in most heart failure trials contributes to the suboptimal treatment of this high-risk population in clinical practice. In the present review, we briefly examine the pathophysiologic mechanisms connecting chronic kidney disease and chronic heart failure and discuss the therapeutic approach to patients affected by both conditions.

Mild hyperkalemia and outcomes in chronic heart failure: a propensity matched study

BACKGROUND

Compared with serum potassium levels 4-5.5 mEq/L, those <4 mEq/L have been shown to increase mortality in chronic heart failure (HF). Expert opinions suggest that serum potassium levels >5.5 mEq/L may be harmful in HF. However, little is known about the safety of serum potassium 5-5.5 mEq/L.

METHODS

Of the 7788 chronic HF patients in the Digitalis Investigation Group trial, 5656 had serum potassium 4-5.5 mEq/L. Of these, 567 had mild hyperkalemia (5-5.5 mEq/L) and 5089 had normokalemia (4-4.9 mEq/L). Propensity scores for mild hyperkalemia were used to assemble a balanced cohort of 548 patients with mild hyperkalemia and 1629 patients with normokalemia. Cox regression models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for association between mild hyperkalemia and mortality during a median follow-up of 38 months.

RESULTS

All-cause mortality occurred in 36% and 38% of matched patients with normokalemia and mild hyperkalemia respectively (HR, 1.07; 95% CI, 0.90-1.26; P=0.458). Unadjusted, multivariable-adjusted, and propensity-adjusted HRs for mortality associated with mild hyperkalemia were 1.33 (95% CI, 1.15-1.52; P<0.0001), 1.16 (95% CI, 1.01-1.34; P=0.040) and 1.13 (95% CI, 0.98-1.31; P=0.091) respectively. Mild hyperkalemia had no association with cardiovascular or HF mortality or all-cause or cardiovascular hospitalization.

CONCLUSION

Serum potassium 4-4.9 mEq/L is optimal and 5-5.5 mEq/L appears relatively safe in HF. Despite lack of an intrinsic association , the bivariate association of mild-hyperkalemia with mortality suggests that it may be useful as a biomarker of poor prognosis in HF.

Incidence of risk factors for developing hyperkalemia when using ACE inhibitors in cardiovascular diseases

STUDY OBJECTIVE

To determine the incidence of and the risk factors associated with hyperkalemia, induced by ACEI-drug interactions among cardiac patients.

SETTING

Five medical and cardiology wards of a tertiary care center in Malaysia.

SUBJECTS

Five hundred cardiac inpatients, who received ACEIs concomitantly with other interacting drugs.

METHOD

This was a prospective cohort study of 500 patients with cardiovascular diseases admitted to Penang Hospital between January to August 2006, who received ACEIs concomitantly with other interacting drugs. ACEI-drug interactions of clinical significance were identified using available drug information resources. Drug Interaction Probability Scale (DIPS) was used to assess the causality of association between ACEI-drug interactions and the adverse outcome (hyperkalemia).

MAIN OUTCOME MEASURE

Hyperkalemia as an adverse clinical outcome of the interaction was identified from laboratory investigations.

RESULTS

Of the 489 patients included in the analysis, 48 (9.8%) had hyperkalemia thought to be associated with ACEI-drug interactions. Univariate analysis using binary logistic regression revealed that advanced age (60 years or more), and taking more than 15 medications were independent risk factors significantly associated with hyperkalemia. However, current and previous smoking history appeared to be a protective factor. Risk factors identified as predictors of hyperkalemia secondary to ACEI-drug interactions by multi-logistic regression were: advanced age (adjusted OR 2.3, CI 1.07-5.01); renal disease (adjusted OR 4.7, CI 2.37-9.39); hepatic disease (adjusted OR 5.2, CI 1.08-25.03); taking 15-20 medications (adjusted OR 4.4, CI 2.08-9.19); and taking 21-26 medications (adjusted OR 9.0, CI 1.64-49.74).

CONCLUSION

Cardiac patients receiving ACEIs concomitantly with potentially interacting drugs are at high risk of experiencing hyperkalemia. Old age, renal disease, hepatic disease, and receiving large number of medications are factors that may significantly increase their vulnerability towards this adverse outcome; thus, frequent monitoring is advocated.

Clinical factors affecting serum potassium concentration in cardio-renal decompensation syndrome

BACKGROUND

Renin-angiotensin-aldosterone system (RAAS) inhibitors are currently indispensable for the treatment of heart failure. It is well known that hyperkalemia is likely to occur in renal failure; however, it has not yet been clarified how the serum potassium concentration changes as heart failure progresses. Currently, the cardio-renal decompensation syndrome holds that the serum potassium concentration is altered similarly by both heart failure and renal failure; however, there are no definitive reports on this. In order to use RAAS inhibitors more safely and effectively in heart failure, it is necessary to understand the factors affecting serum potassium concentration in the clinical setting.

METHODS AND RESULTS

We examined the clinical factors affecting serum potassium concentration in 1035 consecutive patients with cardiovascular disease who were hospitalized in our institution. Multiple regression analysis showed that the independent factors associated with an elevated serum potassium concentration were renal insufficiency evaluated by estimated glomerular filtration rate (eGFR) (P<0.0001), diabetes mellitus evaluated by HbA(1c) (P=0.0005) and the use of RAAS inhibitors (P=0.0010). The independent factors associated with a decreased serum potassium concentration were mean blood pressure (P<0.0001), heart failure evaluated by log BNP (P=0.0164) and the use of diuretics (P=0.0232).

CONCLUSIONS

The serum potassium concentration decreases with the severity of heart failure if renal function is preserved. From the perspective of potassium homeostasis, we could use the RAAS inhibitors more aggressively in patients with heart failure who do not have renal failure.

Hyperkalemia risk and treatment of heart failure

This article briefly reviews the participation of the kidney in heart failure and the renal consequences of the treatment, with special emphasis on the risk for hyperkalemia and its management in daily clinical practice.

Maintaining fluid and electrolyte balance in heart failure

Advanced heart failure and its treatment are often associated with a variety of hemodynamic, fluid, and electrolyte derangements. This article gives the practitioner an overview of the pathophysiology of common fluid and electrolyte alterations present in animals with heart failure, highlighting specific clinical correlates. Additionally, specific therapeutic interventions are discussed to manage these fluid and electrolyte abnormalities.

Relation of low hemoglobin and anemia to morbidity and mortality in patients hospitalized with heart failure (insight from the OPTIMIZE-HF registry)

Anemia in heart failure (HF) is increasingly recognized and treated, but little is known about the prevalence and its relation to outcomes in patients hospitalized for decompensated HF in a situation of both reduced and preserved systolic function. We hypothesized that lower hemoglobin is correlated with death during hospitalization and 60 to 90 days postdischarge in patients with HF. The Organized Program to Initiate Lifesaving Treatment in Patients with Heart Failure is a registry and performance improvement program for hospitalized patients with HF. Study cohorts were defined by admission hemoglobin quartile. Data from 48,612 patients at 259 hospitals showed that half of the total cohort had low hemoglobin (<12.1 g/dl) and that 25% were moderately to severely anemic (lowest hemoglobin quartile, 5 to 10.7 g/dl). Patients with low hemoglobin were older, were more often women and Caucasian, and had preserved systolic function and elevated creatinine. They were also less likely to receive angiotensin-converting enzyme inhibitors and beta blockers at discharge. Anemic patients had higher in-hospital mortality (4.8% vs 3.0%, lowest vs highest quartile), longer hospital length of stay (6.5 vs 5.3 days), and more readmissions by 90 days (33.1% vs 24.2%) (all p <0.0001). In conclusion, these data reveal a higher prevalence of low hemoglobin in hospitalized patients than noted in randomized HF trials and outpatient registries. Lower hemoglobin is associated with higher morbidity and mortality in hospitalized patients with HF.