Hyponatraemia in heart failure

The impact of sodium-glucose co-transporter-2 inhibitors on serum sodium and potassium in patients with Heart Failure: a systematic review and meta-analysis

BACKGROUND

Managing electrolyte abnormalities, particularly sodium and potassium, in patients with heart failure (HF) remains a concern. A novel anti-diabetic drug, sodium-glucose co-transporter-2 (SGLT2) inhibitors, has become suitable for HF patients, improving cardiovascular outcomes. Therefore, we aimed to conduct a meta-analysis to evaluate the effect of SGLT2 inhibitors on serum sodium and potassium.

METHODS

We systematically searched five databases, identifying randomized clinical trials (RCTs) reporting changes in serum sodium and potassium levels with SGLT2 inhibitors compared to comparator groups. Outcomes were presented as weighted mean differences (WMD) and standardized MD (SMD) with 95% confidence intervals (CI). Subgroup and sensitivity analyses were also conducted.

RESULTS

13 studies were included, with 13 studies with 10,617 participants reporting on serum sodium and nine studies with 9877 participants on serum potassium. In acute HF, SGLT2 inhibitors did not significantly affect serum sodium (WMD: 1.21 mmol/L; 95% CI: - 0.79, 3.21) or potassium levels (WMD: 0.11 mEq/L; 95% CI: - 0.20, 0.42). Subgroup analyses suggested possible variations by follow-up duration (< 7 days vs. ≥ 30 days) and drug type, but findings remained non-significant. Sensitivity analysis using the leave-one-out method and risk of bias assessment results showed no considerable changes in the statistical significance of the pooled results. Similarly, in chronic HF, no significant differences were observed for serum sodium (WMD: 0.23 mmol/L; 95% CI: - 0.45, 0.91) or potassium (WMD: 0.07 mEq/L; 95% CI: - 0.29, 0.44). Sensitivity and subgroup analyses based on duration, drug type, diabetes status, renal function, or systolic blood pressure did not reveal clinically meaningful differences across all analyses. For all analyses, Egger's test was non-significant, indicating no strong evidence of small-study effects. Moreover, the trim-and-fill method combined with the funnel plot did not identify any missing studies, and the recalculated effect size remained unchanged.

CONCLUSIONS

SGLT2 inhibitors did not significantly alter serum sodium or potassium levels in acute or chronic HF, suggesting that these drugs can be safe regarding electrolyte disturbances. Additional RCTs are warranted to enhance the robustness of evidence regarding the mechanisms and effects of SGLT2 inhibitors on serum electrolyte levels, considering variations across different types of SGLT2 inhibitors.

Vibrio harveyi co-infected with Cryptocaryon irritans to orange-spotted groupers Epinephelus coioides

The orange-spotted grouper (Epinephelus coioides) is a high economic value aquacultural fish in China, however, it often suffers from the outbreak of parasitic ciliate Cryptocaryon irritans as well as bacterium Vibrio harveyi which bring great loss in grouper farming. In the present study, we established a high dose C. irritans local-infected model which caused the mortality of groupers which showed low vitality and histopathological analysis demonstrated inflammatory response and degeneration in infected skin, gill and liver. In addition, gene expression of inflammatory cytokines was detected to assist the estimate of inflammatory response. Furthermore, we also found that the activity of Na⁺/K⁺ ATPase in gill was decreased in groupers infected C. irritans and the concentration of Na⁺/Cl^- in blood were varied. Base on the morbidity symptom occurring in noninfected organs, we hypothesized that the result of morbidity and mortality were due to secondary bacterial infection post parasitism of C. irritans. Moreover, four strains of bacteria were isolated from the infected site skin and liver of local-infected groupers which were identified as V. harveyi in accordance of phenotypic traits, biochemical characterization and molecular analysis of 16S rDNA genes, housekeeping genes (gyrB and cpn60) and species-specific gene Vhhp2. Regression tests of injecting the isolated strain V. harveyi has showed high pathogenicity to groupers. In conclusion, these findings provide the evidence of coinfections with C. irritans and V. harveyi in orange-spotted grouper.

Relationship of Dapagliflozin With Serum Sodium: Findings From the DAPA-HF Trial

OBJECTIVES

This study aimed to assess the prognostic importance of hyponatremia and the effects of dapagliflozin on serum sodium in the DAPA-HF (Dapagliflozin And Prevention of Adverse outcomes in Heart Failure) trial.

BACKGROUND

Hyponatremia is common and prognostically important in hospitalized patients with heart failure with reduced ejection fraction, but its prevalence and importance in ambulatory patients are uncertain.

METHODS

We calculated the incidence of the primary outcome (cardiovascular death or worsening heart failure) and secondary outcomes according to sodium category (≤135 and >135 mmol/L). Additionally, we assessed: 1) whether baseline serum sodium modified the treatment effect of dapagliflozin; and 2) the effect of dapagliflozin on serum sodium.

RESULTS

Of 4,740 participants with a baseline measurement, 398 (8.4%) had sodium ≤135 mmol/L. Participants with hyponatremia were more likely to have diabetes, be treated with diuretics, and have lower systolic blood pressure, left ventricular ejection fraction, and estimated glomerular filtration rate. Hyponatremia was associated with worse outcomes even after adjustment for predictive variables (adjusted HRs for the primary outcome 1.50 [95% CI: 1.23-1.84] and all-cause death 1.59 [95% CI: 1.26-2.01]). The benefits of dapagliflozin were similar in patients with and without hyponatremia (HR for primary endpoint: 0.83 [95% CI: 0.57-1.19] and 0.73 [95% CI: 0.63-0.84], respectively, P for interaction = 0.54; HR for all-cause death: 0.85 [95% CI: 0.56-1.29] and 0.83 [95% CI: 0.70-0.98], respectively, P for interaction = 0.96). Between baseline and day 14, more patients on dapagliflozin developed hyponatremia (11.3% vs 9.4%; P = 0.04); thereafter, this pattern reversed and at 12 months fewer patients on dapagliflozin had hyponatremia (4.6% vs 6.7%; P = 0.003).

CONCLUSIONS

Baseline serum sodium concentration was prognostically important, but did not modify the benefits of dapagliflozin on morbidity and mortality in heart failure with reduced ejection fraction. (Study to Evaluate the Effect of Dapagliflozin on the Incidence of Worsening Heart Failure or Cardiovascular Death in Patients With Chronic Heart Failure [DAPA-HF]: NCT03036124).

Hyponatraemia in heart failure: time for new solutions?

Hyponatraemia is very common in heart failure (HF), especially in decompensated patients. It is associated with increased mortality and morbidity and considered a marker of advanced disease. Recognition of hyponatraemia and its causes may help guide treatment strategy. Historically, therapy has primarily focused on water restriction, decongestion with loop diuretics in case of volume overload (dilutional hyponatraemia) and sodium repletion in case of depletion. In this review, we summarise the potential benefits of established and emerging HF therapies on sodium homeostasis, with a focus on dual vasopressin antagonists, angiotensin receptor-neprilysin inhibitors, sodium-glucose cotransporter 2 inhibitors and hypertonic saline, and propose a potential therapeutic approach for hyponatraemia in HF.