Use of digoxin and risk of death or readmission for heart failure and sinus rhythm: A nationwide propensity score matched study

Prognostic value of the duke activity Status Index Questionnaire in predicting mortality in patients with chronic heart failure: 36-month follow-up study

BACKGROUND

The Duke Activity Status Index (DASI) questionnaire has been the focus of numerous investigations - its discriminative and prognostic capacity has been continuously explored, supporting its use in the clinical setting, specifically during rehabilitation in patients with chronic heart failure (CHF).However, studies exploring optimal DASI questionnaire threshold scores are limited.

OBJECTIVE

To investigate optimal DASI questionnaire thresholds values in predicting mortality in a CHF cohort and assess mortality rates based on the DASI questionnaire using a thresholds values obtained.

METHODOLOGY

This is a prospective cohort study with a 36-month follow-up in patients with CHF. All patients completed a clinical assessment, followed by DASI questionnaire, pulmonary function, and echocardiography. The Receiver Operating Characteristic (ROC) curve analysis was used to discriminate the DASI questionnaire score in determining the risk of mortality. For survival analysis, the Kaplan-Meier model was used to explore the impact of ≤/>23 points on mortality occurring during the 36-month follow-up.

RESULTS

One hundred and twenty-four patients were included, the majority being elderly men. Kaplan Meier analysis revealed that ≤/> 23 was a strong predictor of CHF mortality over a 36-month follow-up.

CONCLUSION

A score of ≤/>23 presents good discriminatory capacity to predict mortality risk in 36 months in patients with CHF, especially in those with reduced or mildly reduced ejection fraction. Age, ejection fraction, DASI questionnaire score and use of digoxin are risk factors that influence mortality in this population.

Digoxin and Risk of Ventricular Tachyarrhythmia and Death in ICD Recipients

BACKGROUND

Some studies have shown digoxin use to be associated with adverse outcomes, including increased mortality. There are limited data on whether digoxin use is associated with increased risk of ventricular tachycardia/ventricular fibrillation (VT/VF) in heart failure patients with an implantable cardioverter-defibrillator (ICD).

OBJECTIVES

This study sought to assess whether digoxin use is associated with increased risk of VT/VF in patients with heart failure with reduced ejection fraction with a primary prevention ICD in landmark clinical trials.

METHODS

The study cohort consisted of patients with an ICD or cardiac resynchronization therapy-defibrillator who were enrolled in 4 landmark MADIT trials (Multicenter Automatic Defibrillator Implantation Trials). We employed propensity score quintile stratification for treatment with digoxin as well as additional multivariable adjustment to assess the risk of digoxin vs no-digoxin therapy for the endpoints of first and recurrent VT/VF and all-cause mortality. The proportional hazards regression models for arrhythmia-specific endpoints incorporated adjustments for the competing risk of death.

RESULTS

At baseline, 1,155 of 4,499 patients were on digoxin (26%). After propensity score quintile stratification, patients prescribed digoxin were shown to exhibit a statistically significant 48% increased risk of VT/VF (P < 0.001), 42% increased risk of the composite of VT/VF or death (P < 0.001), and a 37% increased risk of all-cause mortality (P = 0.006). Digoxin use was also associated with increased risk of appropriate ICD shocks (HR: 1.91; P < 0.001) and with increased burden of VT/VF events (HR: 1.46; P = 0.001).

CONCLUSIONS

Our findings suggests that digoxin use is associated with ventricular tachyarrhythmia and death in heart failure with reduced ejection fraction patients with an ICD.

Navigating Heart Failure: Unveiling Sex Disparities in Guideline-Directed Medical Therapy Combinations

Major heart failure (HF) trials remain insufficient in terms of assessing the differences in clinical characteristics, biomarkers, treatment efficacy, and safety because of the under-representation of women. The study aimed to present sex-related disparities in HF management, including differences in demographics, co-morbidities, cardiac biomarkers, prescribed medications, and treatment outcomes. The study utilized anonymized data from the Turkish Ministry of Health's National Electronic Database between January 1, 2016, and December 31, 2022. The cohort analysis included 2,501,231 adult patients with HF. Specific therapeutic combinations were analyzed using a Cox regression model to obtain relative risk reduction for all-cause death. The primary end point was all-cause mortality. In the cohort, 48.7% (n = 1,218,911) were male, whereas 51.3% (n = 1,282,320) were female. Female patients exhibited a higher median age (71 vs 68 years) and manifested higher prevalence of diabetes mellitus, anemia, atrial fibrillation, anxiety, and ischemic stroke. Male patients demonstrated higher rates of previous myocardial infarction, dyslipidemia, chronic obstructive pulmonary disease, and chronic kidney disease. Higher concentrations of natriuretic peptides were observed in female patients. Renin-angiotensin aldosterone inhibitor, β blockers, mineralocorticoid receptor antagonists, sodium/glucose cotransporter 2 inhibitor (SGLT2i), and ivabradine were more commonly prescribed in male patients, whereas loop diuretics, digoxin, and ferric carboxymaltose were more frequent in female patients. Male patients had higher rates of cardiac resynchronization therapy and implantable cardioverter defibrillator implantation rates. All-cause mortality and hospitalization rates were higher in male patients. Compared with monotherapy, all combinations, including SGLT2i, showed a beneficial effect on all-cause mortality in both female and male patients with HF. In hospitalized patients with HF, the addition of digoxin to renin-angiotensin aldosterone inhibitor, mineralocorticoid receptor antagonists, and β blockers was superior to monotherapy regarding all-cause mortality in female patients with HF compared with male patients with HF. In conclusion, this study highlights that sex-specific responses to HF medication combinations compared with monotherapy and differences in co-morbidities underscore the importance of tailored management strategies. Digoxin showed a contrasting effect on all-cause mortality between both sexes after hospitalization, whereas SGLT2i exhibited a consistent beneficial effect in both sexes when added to all combinations.

Digoxin, mortality, and cardiac hospitalizations in patients with atrial fibrillation and heart failure with reduced ejection fraction and atrial fibrillation: An AF-CHF analysis

BACKGROUND

Recent publications have raised serious concerns regarding the safety of digoxin for atrial fibrillation (AF). However, the subgroup of patients with reduced ejection fraction and AF have been speculated to derive clinical benefit from digoxin. We aimed to assess the impact of digoxin on mortality and cardiovascular hospitalizations in the Atrial Fibrillation and Congestive Heart Failure (AF-CHF) trial since all AF-CHF patients had an ejection fraction ≤35% and AF.

METHODS AND RESULTS

Using marginal structural modeling, a contemporary statistical method that overcomes limitations of traditional modeling techniques and reduces bias, we assessed the impact of digoxin on the pre-specified primary and secondary outcomes of the AF-CHF trial, i.e., all-cause, cardiac and arrhythmic death as well as cardiovascular hospitalization. Among 1376 patients, 869 (65%) were on digoxin at one-year follow-up. Over a mean (SD) follow-up of 37 (19) months (maximum 74 months), 445 (32%) patients died, 357 (26%) from cardiovascular causes and 159 (12%) from arrhythmic death. Digoxin was significantly associated with all-cause, cardiac, and arrhythmic death, with estimated hazard ratios (HR) of 1.39 (95% confidence interval [CI] 1.11-1.73, P = 0.004), 1.44 (95% CI 1.13-1.82, P = 0.003), and 2.03 (95% CI 1.63-2.54, P < 0.0001), respectively. Digoxin was not associated with cardiovascular hospitalizations [HR 1.12 (95% CI 0.91-1.37), P = 0.29].

CONCLUSION

Digoxin is associated with increased all-cause mortality among patients with combined heart failure with reduced ejection fraction and AF, which is predominantly driven by arrhythmic deaths. In contrast, cardiovascular hospitalizations were not impacted by digoxin.

Digoxin is associated with worse outcomes in patients with heart failure with reduced ejection fraction

AIMS

The aim of this study was to investigate the impact of digoxin use on the outcomes of patients with heart failure with reduced ejection fraction (HFrEF) and its possible interaction with atrial fibrillation or use of currently guideline-recommended treatments in the real world in China.

METHODS AND RESULTS

Patients hospitalized with HFrEF from 45 hospitals participating in the China National Heart Failure Registration Study (CN-HF) were enrolled to assess the all-cause mortality, HF mortality, all-cause re-hospitalization, and HF re-hospitalization associated with digoxin use. Eight hundred eighty-two eligible HFrEF patients in the CN-HF registry were included: 372 patients with digoxin and 510 patients without digoxin. Among them, 794 (90.0%) patients were followed up for the endpoint events, with a median follow-up of 28.6 months. Kaplan-Meier survival analysis showed that the all-cause mortality (P < 0.001) and all-cause re-hospitalization (P = 0.020) were significantly higher in digoxin group than non-digoxin group, while HF mortality (P = 0.232) and HF re-hospitalization (P = 0.098) were similar between the two groups. The adjusted Cox proportional-hazards regression analysis demonstrated that digoxin use remained as an independent risk factor for increased all-cause mortality [hazard ratio (HR) 1.76; 95% confidence interval (CI) 1.27-2.44; P = 0.001] and all-cause re-hospitalization (HR 1.27; 95% CI 1.03-1.57; P = 0.029) in HFrEF patients and the predictive value of digoxin for all-cause mortality irrespective of rhythm or in combination with other guideline-recommended therapies.

CONCLUSIONS

Digoxin use is independently associated with increased risk of all-cause mortality and all-cause re-hospitalization in HFrEF patients.

Questionable utility of digoxin in left-ventricular assist device recipients: A multicenter, retrospective analysis

Background

While clinical experience with left ventricular assist devices (LVAD) continues to grow and evolve, little is known regarding the ongoing use of certain medications in this population. We sought to evaluate the utility of digoxin in LVAD recipients and its association with outcomes.

Methods

A total of 505 patients who underwent continuous-flow LVAD implantation at 5 centers from 2007–2015 were included. Patients were divided into 4 groups: not on digoxin at any time (ND; n = 257), received digoxin pre implant (PreD; n = 144), received digoxin pre and post implant (ContD; n = 55), and received digoxin only post implant (PostD; n = 49). Survival and all-cause readmission were compared between the 4 groups.

Results

There was no difference in survival at 1 year nor at 3 years between groups (ND = 88%, 66%, respectively; PreD = 85%, 66%; ContD = 86%, 57%; PostD = 90%, 51%; p = 0.7). Readmission per 100 days also was not different between groups (ND = 0.5, PreD = 0.6, ContD = 0.5, PostD = 0.7; p = 0.1).

Conclusions

In this large, multicenter cohort, use of digoxin was not associated with any significant benefit in regard to mortality or hospitalization in patients supported with a continuous-flow LVAD. Importantly, its discontinuation post implant did not worsen all-cause hospitalization or survival.

Digoxin sensitizes gemcitabine-resistant pancreatic cancer cells to gemcitabine via inhibiting Nrf2 signaling pathway

Chemoresistance is a major therapeutic obstacle in the treatment of human pancreatic ductal adenocarcinoma (PDAC). As an oxidative stress responsive transcription factor, nuclear factor erythroid 2-related factor 2 (Nrf2) regulates the expression of cytoprotective genes. Nrf2 not only plays a critical role in chemoprevention, but also contributes to chemoresistance. In this study, we found that digoxin markedly reversed drug resistance of gemcitabine by inhibiting Nrf2 signaling in SW1990/Gem and Panc-1/Gem cells. Further research revealed that digoxin regulated Nrf2 at transcriptional level. In in vivo study, we found that digoxin and gemcitabine in combination inhibited tumor growth more substantially when compared with gemcitabine treatment alone in SW1990/Gem-shControl cells-derived xenografts. In the meantime, SW1990/Gem-shNrf2 cells-derived xenografts responded to gemcitabine and combination treatment similarly, suggesting that digoxin sensitized gemcitabine-resistant human pancreatic cancer to gemcitabine, which was Nrf2 dependent. These results demonstrated that digoxin might be used as a promising adjuvant sensitizer to reverse chemoresistance of gemcitabine-resistant pancreatic cancer to gemcitabine via inhibiting Nrf2 signaling.

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Digoxin could reverse drug resistance of gemcitabine in gemcitabine-resistant pancreatic cancer cells.

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Digoxin significantly inhibited Nrf2 signaling in gemcitabine-resistant pancreatic cancer cells.

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Digoxin-mediated reversing drug resistance of gemcitabine in gemcitabine-resistant pancreatic cancer cells was Nrf2 dependent.

Meta-Analysis of Effects of Digoxin on Survival in Patients with Atrial Fibrillation or Heart Failure: An Update

In 2015, 3 independent meta-analyses raised concerns about digoxin therapy being associated with an increased mortality risk in patients with atrial fibrillation (AF) and with heart failure (HF). Although several other studies have been published since then fostering these safety issues, the most recent 2016 European guidelines for AF still recommend this therapy as a class I indication. We performed an updated systematic review and random-effect meta-analysis on publications up to March 2018 reporting data on digoxin associated mortality in subjects with AF or HF. Based on the adjusted survival data of all identified 37 trials comprising a total of 825,061 patients, digoxin use was associated with an increased relative risk of all-cause mortality (hazard ratio [HR] 1.17, 95% confidence interval [CI] 1.05 to 1.29, p <0.01). Treatment with digoxin was associated with an increased mortality risk in the subgroup of patients with AF (n = 627,620, HR 1.23, 95% CI, 1.17 to 1.30, p <0.01), and in the subgroup of patients with HF (n = 197,441, HR 1.11, 95% CI, 1.06 to 1.16, p<0.01). A sensitivity analysis of studies reporting data on new digoxin users (n = 41,687) demonstrated an even higher risk for all-cause mortality compared with patients not receiving cardiac glycosides (HR 1.47, 95% CI, 1.15 to 1.88, p <0.01). In conclusion, this updated meta-analysis confirms that digoxin use is associated with increased mortality in patients with AF or HF.

Association is not causation: treatment effects cannot be estimated from observational data in heart failure

Aims

Treatment 'effects' are often inferred from non-randomized and observational studies. These studies have inherent biases and limitations, which may make therapeutic inferences based on their results unreliable. We compared the conflicting findings of these studies to those of prospective randomized controlled trials (RCTs) in relation to pharmacological treatments for heart failure (HF).

Methods and results

We searched Medline and Embase to identify studies of the association between non-randomized drug therapy and all-cause mortality in patients with HF until 31 December 2017. The treatments of interest were: angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, beta-blockers, mineralocorticoid receptor antagonists (MRAs), statins, and digoxin. We compared the findings of these observational studies with those of relevant RCTs. We identified 92 publications, reporting 94 non-randomized studies, describing 158 estimates of the 'effect' of the six treatments of interest on all-cause mortality, i.e. some studies examined more than one treatment and/or HF phenotype. These six treatments had been tested in 25 RCTs. For example, two pivotal RCTs showed that MRAs reduced mortality in patients with HF with reduced ejection fraction. However, only one of 12 non-randomized studies found that MRAs were of benefit, with 10 finding a neutral effect, and one a harmful effect.

Conclusion

This comprehensive comparison of studies of non-randomized data with the findings of RCTs in HF shows that it is not possible to make reliable therapeutic inferences from observational associations. While trials undoubtedly leave gaps in evidence and enrol selected participants, they clearly remain the best guide to the treatment of patients.

Augmentation of Ouabain-Induced Increase in Heart Muscle Contractility by Akt Inhibitor MK-2206

Cardiac steroids (CSs), such as ouabain and digoxin, increase the force of contraction of heart muscle and are used for the treatment of congestive heart failure (CHF). However, their small therapeutic window limits their use. It is well established that Na+, K+-ATPase inhibition mediates CS-induced increase in heart contractility. Recently, the involvement of intracellular signal transduction was implicated in this effect. The aim of the present study was to test the hypothesis that combined treatment with ouabain and Akt inhibitor (MK-2206) augments ouabain-induced inotropy in mammalian models. We demonstrate that the combined treatment led to an ouabain-induced increase in contractility at concentrations at which ouabain alone was ineffective. This was shown in 3 experimental systems: neonatal primary rat cardiomyocytes, a Langendorff preparation, and an in vivo myocardial infarction induced by left anterior descending coronary artery (LAD) ligation. Furthermore, cell viability experiments revealed that this treatment protected primary cardiomyocytes from MK-2206 toxicity and in vivo reduced the size of scar tissue 10 days post-LAD ligation. We propose that Akt activity imposes a constant inhibitory force on muscle contraction, which is attenuated by low concentrations of MK-2206, resulting in potentiation of the ouabain effect. This demonstration of the increase in the CS effect advocates the development of the combined treatment in CHF.

Chronic digitalis therapy in patients before heart transplantation is an independent risk factor for increased posttransplant mortality

Objectives

Digitalis therapy (digoxin or digitoxin) in patients with heart failure is subject to an ongoing debate. Recent data suggest an increased mortality in patients receiving digitalis. This study investigated the effects of chronic digitalis therapy prior to heart transplantation (HTX) on posttransplant outcomes.

Patients and methods

This was a retrospective, observational, single-center study. It comprised 530 adult patients who were heart-transplanted at Heidelberg University Hospital between 1989 and 2012. Patients with digitalis prior to HTX (≥3 months) were compared to those without (no or <3 months of digitalis). Patients with digitalis were further subdivided into patients receiving digoxin or digitoxin. Primary outcomes were early posttransplant atrial fibrillation and mortality.

Results

A total of 347 patients (65.5%) had digitalis before HTX. Of these, 180 received digoxin (51.9%) and 167 received digitoxin (48.1%). Patients with digitalis before HTX had a significantly lower 30-day (P=0.0148) and 2-year (P=0.0473) survival. There was no significant difference between digoxin and digitoxin in 30-day (P=0.9466) or 2-year (P=0.0723) survival. Multivariate analysis for posttransplant 30-day mortality showed pretransplant digitalis therapy as an independent risk factor (hazard ratio =2.097, CI: 1.036–4.248, P=0.0397). Regarding atrial fibrillation in the early posttransplant period, there was neither a statistically significant difference between patients with and without digitalis (P=0.1327) nor between patients with digoxin or digitoxin (P=0.5867).

Conclusion

Digitalis in patients before HTX is an independent risk factor for increased posttransplant mortality.