Heart failure & cardiomyopathies
Serum Magnesium and the Effect of Empagliflozin in Heart Failure With Reduced Ejection Fraction: Findings From EMPEROR-Reduced
Authors' conclusion
In EMPEROR-Reduced, low serum magnesium levels were modestly associated with poor HF and kidney outcomes. Empagliflozin increased serum magnesium levels and was associated with a more pronounced reduction of HF events among patients with low magnesium levels at baseline.
Study context
- Population
- Patients with heart failure with reduced ejection fraction (HFrEF)
- Participants
- 3,730 patients
- Comparison
- Empagliflozin vs placebo, by baseline serum magnesium quintile
- Primary endpoint
- CV death or HF hospitalization
- Follow-up
- Median 16 months
Primary result
As reported in the abstract
CV death or HF hospitalization, by baseline magnesium quintile
Empagliflozin vs PlaceboHazard ratio (95% CI)
Q1 (0.68 ± 0.07 mmol/L, n = 878)
0.54(0.41–0.71)
Q2 (0.79 ± 0.02, n = 724)
0.69(0.50–0.96)
Q3 (0.84 ± 0.01, n = 668)
0.82(0.58–1.15)
Q4 (0.88 ± 0.02, n = 733)
0.99(0.72–1.37)
Q5 (0.97 ± 0.05, n = 727)
0.87(0.65–1.17)
Further findings
Baseline serum magnesium
- Mean serum magnesium
- 0.83 ± 0.11 mmol/L
Association of magnesium with outcomes
- Lower magnesium modestly associated with higher risk of heart failure (HF) and kidney events; attenuated with full covariate adjustment
Effect of empagliflozin on serum magnesium
- Empagliflozin rapidly increased magnesium levels
- 0.05 mmol/L
- Relative odds of lower magnesium levels reduced with empagliflozin
Original publication
Serum Magnesium and the Effect of Empagliflozin in Heart Failure With Reduced Ejection Fraction: Findings From EMPEROR-Reduced. JACC Heart Fail. Published 31 October 2025. doi:10.
Summarised from the published abstract; every number is checked against it