The association between arterial stiffness, visceral fat rating, and glycemic variability in non-obese adults with type 1 diabetes

Adults with type 1 diabetes mellitus (T1DM) exhibit premature arterial stiffening, but the relative roles of visceral adiposity and glycemic variability remain unclear. We investigated these associations in a group of 120 non-obese adults with T1DM. Carotid–femoral pulse wave velocity (PWV) was measured oscillometrically, and visceral fat rating (VFR) was quantified by multifrequency bioimpedance. Ninety-day continuous glucose monitoring data provided glycemic metrics including mean glucose, time in range (TIR), time above range (TAR), glycemic risk index (GRI), mean amplitude of glycemic excursions (MAGE), mean of daily differences (MODD), and coefficient of variation (CV). Participants (median age 33.8 years, mean BMI 24.3 kg·m⁻²) had a mean PWV of 7.47 ± 1.43 m·s⁻¹. Age was the strongest correlate of PWV (ρ = 0.59, p < 0.001) followed by VFR (ρ = 0.48, p < 0.001). In multivariable models, each standard deviation increase in VFR was associated with a 0.22 m·s⁻¹ higher PWV (p = 0.01), comparable to the effects of systolic blood pressure and diabetes complications. MODD, MAGE, TAR, GRI, and lower TIR modestly improved model fit (ΔR² ≤ 0.08), yet none showed univariate associations. VFR and age are dominant correlates of arterial stiffness in T1DM, while glycemic variability plays a limited role.