HYPERLIPIDEMIA DOES NOT IMPAIR VASCULAR ENDOTHELIAL FUNCTION IN GLYCOGEN-STORAGE-DISEASE TYPE 1A

Patients with glycogen storage disease type 1 (GSD-1) often have marke d hyperlipidaemia with abnormal lipoprotein profiles. This metabolic a bnormality improves, but is not fully corrected, with dietary therapy and therefore these patients may be at high risk for the development o f atherosclerosis. Endothelial dysfunction is an early event in athero genesis and can be detected in children and young adults at high risk. We studied endothelial function, using a non-invasive ultrasonographi c method, in the brachial arteries of 6 adult GSD-1a patients (aged 23 -33 years) with mean cholesterol of 7.9 mmol/l (range 4.7 to 14.6) and mean triglycerides of 9.1 mmol/l (range 4.1 to 21.3), and 12 age- and sex-matched normolipidaemic controls. Flow-mediated (endothelium-depe ndent) dilation was similar in patients and controls (8.2% vs. 10.5%; P = 0.20). Although the patient numbers are small, these results are c onsistent with the surprising lack of clinically evident atheroscleros is in GSD-1. The reasons these patients appear less susceptible to the damaging arterial effects of hyperlipidaemia are unknown. These resul ts may have: implications for others with secondary hyperlipidaemias.