Serum potassium dynamics during acute heart failure hospitalization

Potassium levels and the risk of all-cause and cardiovascular mortality among patients with cardiovascular diseases: a meta-analysis of cohort studies

BACKGROUND

Abnormal blood potassium levels are associated with an increased risk of cardiometabolic diseases and mortality in the general population; however, evidence regarding the association between dyskalemia and mortality among patients with cardiovascular disease (CVD) remains inconclusive. This study aimed to evaluate the association of potassium levels with all-cause and cardiovascular mortality among patients with CVD.

METHODS

PubMed, Embase, Web of Science, and Cochrane Library databases were searched up to August 2023 to identify relevant cohort studies among patients with CVD, such as myocardial infarction, stroke, and heart failure. Abnormal potassium levels were considered as hypokalemia or hyperkalemia. The primary outcomes were all-cause mortality based on follow-up length (including in-hospital, short-term and long-term mortality) and cardiovascular mortality. The methodological quality of included studies was assessed by using the Newcastle-Ottawa Scale. The pooled relative risks (RRs) and 95% confidence intervals (CIs) were calculated using random-effects models. Restricted cubic splines were applied to explore the dose-response relationship.

RESULTS

Thirty-one cohort studies involving 227,645 participants with an average age of 68.3 years were included in the meta-analysis, all of which achieved moderate to high quality. Hyperkalemia was significantly associated with an approximately 3.0-fold increased risk of all-cause in-hospital mortality (RR:2.78,95CI%:1.92,4.03), 1.8-fold of all-cause short-term mortality (RR:1.80, 95CI%:1.44,2.27), 1.3-fold of all-cause long-term mortality (RR:1.33, 95CI%:1.19,1.48) and 1.2-fold of cardiovascular mortality (RR:1.19, 95CI%:1.04,1.36). Similar positive associations were also observed between hypokalemia and risk of all-cause mortality and cardiovascular mortality. The RRs of all-cause in-hospital, short-term, long-term mortality and cardiovascular mortality with hyperkalemia were attenuated to 2.21 (95CI%:1.60,3.06), 1.46(95CI%:1.25,1.71), 1.23 (95CI%:1.09,1.39) and 1.13 (95CI%:1.00,1.27) when treating hypokalemia together with normokalemia as the reference group. A U-shaped association was observed between potassium levels and mortality, with the lowest risk at around 4.2 mmol/L.

CONCLUSIONS

Both hypokalemia and hyperkalemia were positively associated with the risk of mortality in patients with CVD. Our results support the importance of potassium homeostasis for improving the CVD management.

REGISTRATION

PROSPERO, CRD42022324337.

Association between hyponatremia and adverse clinical outcomes of heart failure: current evidence based on a systematic review and meta-analysis

Background

Heart failure (HF) is a global health challenge. The perturbations in fluid and electrolyte equilibrium, particularly the compromised sodium balance associated with HF lead to high mortality rates. Hence, elucidating the correlation between serum sodium levels and the prognosis of HF is of paramount importance. This study aimed to conduct a comprehensive meta-analysis to thoroughly investigate the interplay between hyponatremia and the prognostic outlook of individuals with HF.

Methods

A comprehensive search of bibliographic databases including PubMed, Embase, and the Cochrane Central Register of Controlled Trials was conducted to identify relevant observational studies examining the association between hyponatremia and prognosis of HF. Data extraction, synthesis, and assessment of risk of bias were conducted. Meta-analytic methods, sensitivity analyses, and heterogeneity test were employed as appropriate to synthesize the data.

Results

A total of 43,316 patients with HF were included spanning 25 selected studies. The pooled data revealed a notable association between hyponatremia and elevated risks across short and long-term mortality of HF. Specifically, hyponatremia was found to significantly increase the likelihood of all-cause mortality (Hazard ratio [HR] = 1.94, 95% confidence interval [CI]: 1.78-2.12); 1-year mortality (HR = 1.67, 95%CI: 1.46-1.90); 30-day mortality (HR = 2.03, 95%CI: 1.73-2.25); cardiac mortality (HR = 2.11, 95%CI: 1.81-2.46); and in-hospital mortality (HR = 1.64, 95%CI: 1.15-2.34).

Conclusion

Our meta-analysis emphasizes the significant impact of hyponatremia on mortality in the HF patient population, highlighting the critical importance of maintaining stable serum sodium levels in HF management.

Development and validation of a prognostic nomogram for Takotsubo syndrome patients in the intensive care units: a retrospective cohort study

Patients with Takotsubo syndrome (TTS) admitted to the intensive care unit (ICU) always confront a higher risk of in-hospital death than those hospitalized in the cardiology unit. The prognosis of the latter was analyzed by a large number of studies. However, there was no utility model to predict the risk of in-hospital death for patients with TTS in the ICU. This study aimed to establish a model predicting in-hospital death in patients with TTS admitted to ICU. We retrospectively included ICU patients with TTS from the MIMIC-IV database. The outcome of the nomogram was in-hospital death. Least Absolute Shrinkage Selection Operator (LASSO) analysis selected predictors preliminarily. The model was developed by multivariable logistic regression analysis. Calibration, decision curve analysis (DCA), and receiver operating characteristic (ROC) measured the performance of the nomogram on the accuracy, clinical utility, and discrimination, respectively. Eventually, 368 ICU patients with TTS were enrolled in this research. The in-hospital mortality was 13.04%. LASSO regression and multivariate logistic regression analysis verified risk factors significantly associated with in-hospital mortality. They were potassium, prothrombin time (PT), age, myocardial infarction, white cell count (WBC), hematocrit, anion gap, and sequential organ failure assessment (SOFA) score. This nomogram excellently discriminated against patients with a risk of in-hospital death. The area under curve (AUC) was 0.779 (95%CI: 0.732-0.826) in training set and 0.775 (95%CI: 0.711-0.839) in test set. The calibration plot and DCA showed good clinical benefits for this nomogram. We developed a nomogram that predicts the probability of in-hospital death for ICU patients with TTS. This nomogram was able to discriminate patients with a high risk of in-hospital death and performed clinical utility.

Prevalence, Incidence, and Outcomes of Hyperkalaemia in Patients with Chronic Heart Failure and Reduced Ejection Fraction from a Spanish Multicentre Study: SPANIK-HF Design and Baseline Characteristics

Hyperkalaemia is a growing concern in the treatment of patients with heart failure and reduced ejection fraction (HFrEF) as it limits the use of some prognostic-modifying drugs and has a negative impact on prognosis. The objective of the present study was to estimate the prevalence of hyperkalaemia in outpatients with HFrEF and its impact on achieving optimal medical treatment. For this purpose, a multicentre, prospective, and observational study was carried out on consecutive HFrEF patients who were monitored as outpatients in heart failure (HF) units and who, in the opinion of their doctor, received optimal medical treatment. A total of 565 HFrEF patients were included from 16 specialised HF units. The mean age was 66 ± 12 years, 78% were male, 45% had an ischemic cause, 39% had atrial fibrillation, 43% were diabetic, 42% had a glomerular filtration rate < 60 mL/min/1.7 m2, and the mean left ventricular ejection fraction was 31 ± 7%. Treatment at the study entry included: 76% on diuretics, 13% on ivabradine, 7% on digoxin, 18.9% on angiotensin-conversing enzyme inhibitors (ACEi), 11.3% on angiotensin receptors blockers (ARBs), 63.8% on angiotensin-neprilysin inhibitors (ARNi), 78.5% on mineralocorticoid receptor antagonists (MRAs), and 92.9% on beta-blockers. Potassium levels in the baseline analysis were: ≤5 mEq/L = 80.5%, 5.1−5.4 mEq/L = 13.8%, 5.5−5.9 mEq/L = 4.6%, and ≥6 mEq/L = 1.06%. Hyperkalaemia was the reason for not prescribing or reaching the target dose of an MRAs in 34.8% and 12.5% of patients, respectively. The impact of hyperkalaemia on not prescribing or dropping below the target dose in relation to ACEi, ARBs, and ARNi was significantly less. In conclusion, hyperkalaemia is a frequent problem in the management of patients with HFrEF and a limiting factor in the optimisation of medical treatment.

Prognostic implications of hypo and hyperkalaemia in acute heart failure with reduced ejection fraction. Analysis of cardiovascular mortality and hospital readmissions

BACKGROUND AND OBJECTIVES

Potassium alterations constitute a major clinical problem in decompensated heart failure (HF). This study aims to assess the prognostic implications of hypo and hyperkalaemia on admission for acute HF in cardiovascular mortality and hospital readmissions.

MATERIAL AND METHOD

From January 2016 to June 2020, 1,397 cases with a diagnosis of acute HF were admitted. Admission programmed for study, elective therapies, and patients with LVEF> 40% were excluded. The study was carried out on 689 patients, 45 with K⁺ <3.5 mmol/L, 49K ⁺>5.0 mmol/L and 595K+3.5-5.0 mmol/L. Medical history, baseline clinical profile, drug therapy, and potassium levels obtained upon admission were analysed.

RESULTS

Annual mortality due to hypokalaemia (K+<3.5mmol/L) was 37.8% (HR 2.4; 95% CI: 1.3-4.7; P<.007); for hyperkalaemia 40.8% (HR: 1.9; 95% CI: 0.98-3.51; P<.055). Creatinine level and age were variables associated with mortality in both the hyperkalaemic and hypokalaemic cohorts. Hospital readmissions did not show statistical association with these electrolyte disorders.

CONCLUSIONS

In patients admitted for decompensated HF, both hyperkalaemia and hypokalaemia determined at admission have a negative prognostic impact on survival. Creatinine and age are other independent factors associated with mortality. The effect on the probability of hospital readmission at one year is not demonstrated in this study.