New treatments for hyperkalaemia: clinical use in cardiology

Consensus document on the management of hyperkalemia

Hyperkalaemia is a common electrolyte imbalance with potentially serious short-, medium- and long-term consequences on morbidity and mortality rates and the use of national health service resources. The fact that different medical specialities can manage hyperkalaemia makes it important to have a unified approach, and the recent availability of new specific drug treatments means that the approach needs to be updated. This consensus document from the scientific societies most directly involved in the management of hyperkalaemia (Sociedad Española de Cardiología [Spanish Society of Cardiology], Sociedad Española de Endocrinología y Nutrición [Spanish Society of Endocrinology and Nutrition], Sociedad Española de Medicina Interna [Spanish Society of Internal Medicine], Sociedad Española de Medicina de Urgencias y Emergencias [Spanish Society of Accident and Emergency Medicine] and Sociedad Española de Nefrología [Spanish Society of Nephrology]) first of all reviews basic aspects of potassium balance and blood potassium. Then it goes on to focus on the concept, epidemiology, pathophysiology and diagnostic and therapeutic approaches to hyperkalaemia. The available evidence and the main published studies have been reviewed with the aim of providing a useful tool in the multidisciplinary approach to patients with hyperkalaemia.

Hyperkalemia in Chronic Kidney Disease: Links, Risks and Management

Hyperkalemia is a common clinical problem with potentially fatal consequences. The prevalence of hyperkalemia is increasing, partially due to wide-scale utilization of prognostically beneficial medications that inhibit the renin-angiotensin-aldosterone-system (RAASi). Chronic kidney disease (CKD) is one of the multitude of risk factors for and associations with hyperkalemia. Reductions in urinary potassium excretion that occur in CKD can lead to an inability to maintain potassium homeostasis. In CKD patients, there are a variety of strategies to tackle acute and chronic hyperkalemia, including protecting myocardium from arrhythmias, shifting potassium into cells, increasing potassium excretion from the body, addressing dietary intake and treating associated conditions, which may exacerbate problems such as metabolic acidosis. The evidence base is variable but has recently been supplemented with the discovery of novel oral potassium binders, which have shown promise and efficacy in studies. Their use is likely to become widespread and offers another tool to the clinician treating hyperkalemia. Our review article provides an overview of hyperkalemia in CKD patients, including an exploration of relevant guidelines and nuances around management.

Multiple comorbid conditions and healthcare resource utilization among adult patients with hyperkalemia: A retrospective observational cohort study using association rule mining

Objectives

To estimate the prevalence of specific comorbid conditions (CCs) and multiple comorbid conditions (MCCs) among adult patients with hyperkalemia and examine the associations between MCCs and healthcare resource utilization (HRU) and costs.

Methods

This retrospective observational cohort study was conducted using a large administrative claims database. We identified patients with hyperkalemia (ICD-10-CM: E87.5; or serum potassium >5.0 mEq/L; or NDC codes for either patiromer or sodium polystyrene sulfonate) during the study period (1/1/2016–6/30/2019). The earliest service/claim date with evidence of hyperkalemia was identified as index date. Qualified patients had ≥12 months of enrolment before and after index date, ≥18 years of age. Comorbid conditions were assessed using all data within 12 months prior to the index date. Healthcare resource utilization and costs were estimated using all data within 12 months after the index date. Association rule mining was applied to identify MCCs. Generalized linear models were used to examine the associations between MCCs and HRU and costs.

Results

Of 22,154 patients with hyperkalemia, 94% had ≥3 CCs. The most common individual CCs were chronic kidney disease (CKD, 85%), hypertension (HTN, 83%), hyperlipidemia (HLD, 81%), and diabetes mellitus (DM, 47%). The most common dyad combination of CCs was CKD+HTN (71%). The most common triad combination was CKD+HTN+HLD (62%). The most common quartet combination was CKD+HTN+HLD+DM (36%). The increased number of CCs were significantly associated with increased ED visits, length of hospital stays, and total healthcare costs (all p-value < 0.0001).

Conclusions

MCCs are very prevalent among patients with hyperkalemia and are strongly associated with HRU and costs.

The importance of developing hyperkalaemia in heart failure during long-term follow-up

BACKGROUND

Hyperkalaemia is a potentially life-threatening condition. Furthermore, it is one of the main reasons for discontinuation and dose reduction of renin-angiotensin-aldosterone system inhibitors (RAASi) in clinical practice. However, exact data on the prevalence and consequences of occurrence of hyperkalaemia when taking RAASi in a dedicated heart failure care setting are scarce.

METHODS

Consecutive patients diagnosed with heart failure from a single tertiary hospital between August 2000 and May 2017 were retrospectively evaluated. Primary endpoint was the development of hyperkalaemia (≥5.5 mmol/L) at any moment during follow-up.

RESULTS

About 396 patients were included in the current analysis (mean follow-up 6.9 years). 26% (n = 104) and 12% (n = 46) of patients developed hyperkalaemia (≥5.5 mmol/L and ≥6.0 mmol/L, respectively). Diabetes mellitus (OR = 1.80, 95% CI = 1.03-3.19) and baseline creatinine (mg/dL) (OR = 2.37, 95% CI = 2.37-3.85) were independent risk factors for hyperkalaemia. Development of hyperkalaemia was associated with 6.5 higher odds for recurrence. Only 10% developed hyperkalaemia during up-titration of RAASi, while 90% developed during later follow-up on stable doses of RAASi. hyperkalaemia was not associated with worse outcome after multivariate adjustment for baseline co-morbidities. However, hyperkalaemia was associated with discontinuation and lower doses of MRAs during follow-up (p = 0.007). Discontinuation of MRA due to hyperkalaemia was associated with an increase in all-cause mortality in HFrEF patients (HR = 1.77, 95% CI = 1.05-2.99).

CONCLUSIONS

Approximately, one-fourth of patients developed hyperkalaemia during follow-up which was associated with a lower MRA dose during follow-up. Discontinuation of MRA, but not hyperkalaemia itself, was associated with an increased risk of all-cause mortality and heart failure admission in HFrEF patients.

The Changing Landscape of Acute Kidney Injury in Pregnancy from an Obstetrics Perspective

Pregnancy-related acute kidney injury (PR-AKI) is a heterogeneous disorder with multiple aetiologies that can occur at any time throughout pregnancy and the post-partum period. PR-AKI is an important obstetric complication that is associated with significant maternal and foetal morbidity and mortality. Although there has been an overall decline in the incidence of PR-AKI worldwide, a recent shift in the occurrence of this disease has been reported. Following improvements in obstetric care, PR-AKI incidence has been reduced in developing countries, whereas an increase in PR-AKI incidence has been reported in developed countries. Awareness of the physiological adaptations of the renal system is essential for the diagnosis and management of kidney impairment in pregnancy. In this review we scrutinize the factors that have contributed to the changing epidemiology of PR-AKI and discuss challenges in the diagnosis and management of acute kidney injury (AKI) in pregnancy from an obstetrics perspective. Thereafter we provide brief discussions on the diagnostic approach of certain PR-AKI aetiologies and summarize key therapeutic measures.