Effects of improved glycaemic control on endothelial function in patients with type 2 diabetes.
BACKGROUND
Patients with type 2 diabetes have abnormal endothelial function but it is not certain whether improvements in glycaemic control will improve endothelial function.


OBJECTIVE
To examine the effects of short-term improved glycaemic control on endothelial function in patients with inadequately regulated type 2 diabetes mellitus.


METHODS
Forty-three patients with type 2 diabetes and glycosylated haemoglobin (HbA1c) > 8.9% were randomized to either improved glycaemic control (IC) n = 21 or usual glycaemic control (UC) n = 22 for 20 weeks. Using high-resolution B-mode ultrasound, brachial artery flow-mediated dilatation (FMD) and glyceryl trinitrate-mediated dilatation (GTN-D) were measured at baseline and 20 weeks later.


RESULTS
After 20 weeks, HbA1c was significantly lower in IC versus UC (IC 8.02 +/- 0.25% versus UC 10.23 +/- 0.23%, P < 0.0001) but changes in FMD and GTN-D were not different between the groups (FMD at baseline and week 20 IC 5.1 +/- 0.56% versus 4.9 +/- 0.56% and UC 4.2 +/- 0.51% versus 3.1 +/- 0.51%; P = 0.23: GTN-D IC 12.8 +/- 1.34% versus 10.4 +/- 1.32% and UC 13.7 +/- 1.2% versus 12.7 +/- 1.23%; P = 0.39). In the IC group weight increased by 3.2 +/- 0.8 kg after 20 weeks compared to 0.02 +/- 0.70 kg in UC (P = 0.003). Blood pressure and serum lipid concentrations did not change in either group.


CONCLUSIONS
Short-term reduction of HbA1c levels did not appear to affect endothelial function in patients with type 2 diabetes and previously poorly regulated glycaemic control.
Bagg
W
W
Division of Medicine, Auckland Hospital, Grafton, New Zealand. w.bagg@auckland.ac.nz
Whalley
G A
GA
Gamble
G
G
Drury
P L
PL
Sharpe
N
N
Braatvedt
G D
GD
D001786:Blood Glucose / Q000378:metabolism*; D001916:Brachial Artery / Q000000981:diagnostic imaging; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy* / Q000503:physiopathology; D004730:Endothelium, Vascular / Q000187:drug effects / Q000503:physiopathology*; D005260:Female; D005913:Glipizide / Q000627:therapeutic use; D006442:Glycated Hemoglobin / Q000378:metabolism*; D006801:Humans; D007004:Hypoglycemic Agents / Q000494:pharmacology / Q000627:therapeutic use*; D007328:Insulin / Q000494:pharmacology / Q000627:therapeutic use*; D008297:Male; D008687:Metformin / Q000627:therapeutic use; D008875:Middle Aged; D005996:Nitroglycerin; D013997:Time Factors; D016896:Treatment Outcome; D014463:Ultrasonography
D001786:Blood Glucose; D005913:Glipizide; D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D007328:Insulin; D008687:Metformin; D005996:Nitroglycerin