Association of low‐grade albuminuria and triple‐line pattern as markers of early peripheral vascular remodeling in adolescents with type 1 diabetes

ABSTRACT Background Adolescents with type 1 diabetes (T1D) face premature atherosclerosis, but standard carotid intima‐media thickness (IMT) may lack sensitivity for the earliest vascular injuries. Since urinary albumin‐to‐creatinine ratio (UACR) reflects systemic endothelial dysfunction, we investigated the triple‐line pattern (TLP) as a marker of peripheral remodeling and its dose–response relationship with low‐grade albuminuria. Methods The Subclinical Cardiovascular Disease in Type 1 Diabetes Mellitus (SCVD T1DM) cohort study prospectively recruited 283 adolescents with T1D and 106 age‐ and sex‐matched controls. IMT was measured at the common carotid artery and common femoral artery (CFA) using high‐resolution ultrasound. Logistic regression tested categorical UACR thresholds, and restricted cubic spline models evaluated the continuous dose–response association between UACR and TLP. Results TLP prevalence was higher in type 1 diabetes than in controls (63.9% vs 49.1%, P = 0.008). While type 1 diabetes was associated with carotid thickening, TLP was linked to structural changes in the lower extremities. TLP‐positive participants had greater mean CFA IMT (0.56 ± 0.06 vs 0.44 ± 0.06 mm, P < 0.001). UACR ≥15 mg/g independently predicted TLP (odds ratio 2.83, 95% confidence interval 1.01–7.92, P = 0.048), whereas UACR ≥30 mg/g was not significant. Spline analysis showed no significant nonlinearity (P for nonlinearity = 0.424), with risk increasing above approximately 15 mg/g. Conclusions TLP is a prevalent marker of incipient peripheral vascular remodeling in adolescents with type 1 diabetes without macroalbuminuria. A UACR ≥15 mg/g identifies subclinical vascular risk below conventional thresholds, supporting TLP as a potential tool for refined early risk stratification in this population.