Reduced Venous Compliance in Young Women with Type 1 Diabetes – Further Aggravated by Prolonged Elevated Levels of HbA1c

BACKGROUND: Young patients with diabetes present with reduced compensatory responses to hypovolemic stress. Less compliant veins could be a contributing factor, since roughly two-thirds of the blood volume resides in the venous system as a blood reservoir, adjusting proper venous inflow to the heart. The aim of this study was to measure venous compliance and lower limb blood pooling during hypovolemic stress, and to correlate them to indices of diabetes severity and glucose control. METHODS: Fifteen young women with type 1 diabetes (DW) and 18 healthy age-matched women (C) were subjected to lower body negative pressure (LBNP) (11–44 mmHg), creating hypovolemic stress. Lower limb blood pooling was measured with strain gage technique and venous compliance calculated as the relationship between ∆V/∆P. RESULTS: DW presented with reduced blood pooling (e.g., blood pooling during LBNP of 44 mmHg, DW, 1.69 ± 0.10; C, 2.10 ± 0.08 (ml/100 ml), and P = 0.003). Calculated venous compliance was also reduced in DW (e.g., compliance at 20 mmHg, DW, 0.046 ± 0.003; C, 0.059 ± 0.002 (ml/100 ml/mmHg), and P = 0.002). A progressive reduction in both venous compliance (P < 0.007) and blood pooling (P < 0.005) was seen with increasing level of HbA(1c), and furthermore, less strongly associated with presence of microvascular disease (signs of retinopathy). CONCLUSION: Women with type 1 diabetes present with both reduced venous compliance and blood pooling. The reductions were particularly present in patients with long-standing poor glycemic control.