Masked Hypertension and Its Associations with Glycemic Variability Metrics in Children and Adolescents with Type 1 Diabetes

Masked hypertension defined as having normal office blood pressure (BP) but hypertension detected by continuous BP monitoring has been observed in children and adolescents with type 1 diabetes (T1D). However, no study has evaluated whether masked hypertension is associated with glycemic variability (GV) in these patients. We hypothesized that masked hypertension might be associated with high GV in patients with T1D. This cross-sectional study performed continuous glucose monitoring (CGM) in parallel with ambulatory blood pressure monitoring (ABPM) in T1D patients aged 6–21 years. Patients who had known hypertension were excluded. CGM data from the same day as ABPM was calculated for GV including standard deviation (SD), coefficient of variation (CV) of glucose levels, and unstable glycemia which was defined as having a CV of glucose levels ≥ 36%. Thirty-three patients had complete ABPM and CGM data. Mean (SD) age was 13.8 (3.8) years and mean (SD) duration of T1D was 5.4 (3.6) years. All patients had normal office BP, but ABPM showed masked hypertension in 9 patients (27%). In comparison with normotensive patients, patients with masked hypertension had longer duration of T1D (7.4 vs. 4.6 years, p = 0.049), higher insulin requirement (1.2 vs. 0.9 units/kg/day, p = 0.049), and higher SD of glucose (70.3 vs. 47.9 mg/dl, p = 0.038). Masked hypertension group had a greater number of patients (71% vs. 19%, p = 0.02) with unstable glycemia. Multivariate analysis revealed that unstable glycemia was associated with masked hypertension. The presence of unstable glycemia in children and adolescents with T1D is associated with masked hypertension.