Blood lipids and endothelial function in glycogen storage disease type III

We have assessed early indicators of arterial disease in patients with glyc ogen storage disease type III (GSD III; McKusick 232400), investigating the plasma lipid and lipoprotein profile and endothelial function. Eleven pati ents, aged 10-39 years, were recruited together with age-, sex- and smoking status-matched controls. Brachial artery responses were assessed by high-r esolution ultrasonographic measurement of the diameter of the brachial arte ry at baseline, after reactive hyperaemia and in response to sublingual gly ceryl trinitrate (GTN). The means of plasma cholesterol (total and HDL and LDL subfractions), trigl ycerides, apo-A1, apo-B, Lp(a) and the atherogenic index were similar in bo th groups. Cardiac troponin I was below the lower limits of detection (< 0. 03g/L) in all subjects. The GSD III patients had similar body mass index (B MI) and brachial artery diameter to the control group (BMI 22.6 +/- 5.6 vs 22.3 +/- 5kg/m(2); brachial artery diameter 3.4 +/- 0.5 vs 3 +/- 0.7mm). Wh en compared to the baseline diameter, the maximal flow-mediated dilatation of the brachial artery after reactive hyperaemia was 9.3 +/- 2.1% (mean +/- SD) in the GSD III patients and 6.5 +/- 3.5% in the control group, a diffe rence of 1.8% (95% CI 0.07% to 5.5%). The maximal dilatation of the brachia l artery after GTN administration was 18.3 +/- 6.4% in the GSD III patients and 17.9 +/- 6.5% in the control group, a difference of 0.4% (95% CI -6.9% to 7.7%). In conclusion, we found no evidence of abnormal plasma lipid and lipoprotei n profile or endothelial dysfunction in patients with GSD III. They are unl ikely to be at increased risk of premature atherosclerosis.