Objective: We have reported that renal hyperfiltration is associated with endothelial dysfunction in early type 1 DM. However the relationship between renal hyperfiltration and arterial stiffness is unknown. Accordingly, we measured arterial stiffness in type 1 DM subjects with hyperfiltering (n=20) or normofiltering (n=18).

Methods: Augmentation index (AIx), aortic pulse wave velocity (PWV), renal hemodynamic function (inulin and paraaminohippurate clearances), urinary and circulating plasma cGMP were measured in normoalbuminuric subjects with type 1 DM during clamped euglycemia (glucose 4-6 mmol/L) and hyperglycemia (glucose 9-11 mmol/L).

Results: During clamped euglycemia, hyperfiltering subjects (glomerular filtration rate [GFR] ≥135 ml/min/1.73m²) exhibited lower AIx values (−6.1±2.9% vs. 13.9±2.7%, p=0.001) and higher cGMP levels in urine and plasma compared with normofiltering subjects. These differences were maintained during clamped hyperglycemia. As expected, renal hemodynamic responses to clamped hyperglycemia were exaggerated in normofilterers, but values for AIx remained unchanged.

Conclusions: Renal hyperfiltration is associated with reduced arterial stiffness in subjects with uncomplicated type 1 DM.