Dapagliflozin does not impair microvascular hemorheology in type 2 diabetes mellitus: A multicenter randomized controlled trial (D-PATH study).

AIMS: Sodium-glucose cotransporter 2 inhibitors reduce cardiovascular and renal events beyond glucose lowering, but their hematocrit-raising effects raise concerns about increased blood viscosity and microvascular impairment. We investigated whether dapagliflozin adversely affects microvascular hemorheology in patients with type 2 diabetes.

MATERIALS AND

METHODS

In this multicenter, open-label, randomized controlled trial, 82 adults with type 2 diabetes received dapagliflozin (5 mg/day) or conventional therapy for 16 weeks. The primary endpoint was the change in whole blood passage time (WBPT), measured using a microchannel flow analyzer that simulates precapillary arterioles (7 × 7 μm), with a prespecified noninferiority margin of 6.0 s (15%). Secondary outcomes included apparent microvascular viscosity, adhesive leukocyte count, and oxidative stress markers. Serum erythropoietin (EPO) was evaluated in an ancillary analysis.

RESULTS

WBPT changed minimally in the dapagliflozin group (+1.4 s; 95% CI, 0.0-2.9) and slightly decreased in the control group (-0.6 s; 95% CI, -1.9 to 0.6), yielding a between-group difference of 2.0 s (95% CI, -0.2 to 3.9), with the upper bound below the prespecified noninferiority margin. Microvascular viscosity, hematocrit-standardized viscosity, leukocyte adhesion, and oxidative stress markers remained stable in both groups. Dapagliflozin increased hematocrit and EPO, particularly in participants with lower baseline hematocrit, whereas those with hematocrit >45% showed minimal change.

CONCLUSIONS

Dapagliflozin did not impair microvascular hemorheology despite modest increases in hematocrit and EPO. These findings support the microvascular safety of dapagliflozin and reinforce its role in cardio-renal risk management in type 2 diabetes.