Effects of dapagliflozin on urinary output, fluid balance, and biochemistry in critically ill patients: a post-hoc secondary analysis of the DEFENDER trial.

BACKGROUND

Sodium-glucose cotransport-2 inhibitors (SGLT2i) have established benefits in diabetes mellitus, heart failure, and chronic kidney disease, but their physiological effects during critical illness remain unclear. We explored whether dapagliflozin affected urinary output, fluid balance, and other physiological parameters in critically ill patients with acute organ dysfunction.

METHODS

This secondary analysis of the DEFENDER trial included 401 critically ill patients with acute organ dysfunction randomized to receive dapagliflozin 10 mg daily or standard care. We analyzed urinary output, fluid balance, electrolytes, acid-base status, glycemia, and vasopressor requirements over the first five days using Bayesian models.

RESULTS

Dapagliflozin progressively increased urinary output (day 5: + 157 mL/day, 95% CrI -90 to 386, probability 90%) and decreased fluid balance (day 5: -290 mL/day, 95% CrI -564 to -27, probability 98%). Furosemide use was lower in the dapagliflozin group (overall -3%, 95% CrI -7% to 1%, probability 90%). Dapagliflozin had minimal effects on creatinine and electrolytes but was associated with progressive small decreases in pH (day 5: -0.02, probability 96%). Maximum glucose levels were consistently lower with dapagliflozin (-9 mg/dL overall, probability 83%). Norepinephrine requirements showed a time-dependent increase in the dapagliflozin group, with the expected dose difference reaching 0.034 mcg/kg/min by day 5 (probability 94%), and heterogeneity analysis revealed larger effects in patients with sepsis or on mechanical ventilation.

CONCLUSION

This exploratory analysis suggests dapagliflozin may enhance diuresis and reduce loop diuretic requirements in critically ill patients, potentially at the cost of increased vasopressor needs. Glucose levels were likely slightly lower with dapagliflozin. Given the study's limitations and heterogeneous treatment effects, these findings should be considered hypothesis-generating pending confirmation in prospective trials.