Insulin therapy does not interfere with venous endothelial function evaluation in patients with type 2 diabetes mellitus.
BACKGROUND
Endothelium-dependent dilation is improved in insulin-treated diabetic patients, but this effect is probably due to improved glycemic control. The objective of the present study was to compare endothelium-dependent dilation in patients with well-controlled type 2 diabetes who are or are not using insulin as part of their therapy.


METHODS
We studied 27 patients with type 2 diabetes (11 women, 60.3 years ± 6 years, with HbA1c < 7% and no nephropathy), including 16 patients treated with anti-diabetic agents (No-Ins, 8 women) and 11 patients treated with insulin alone or in combination with anti-diabetic agents (Ins, 3 women). Endothelial function was evaluated by the dorsal hand vein technique, which measures changes in vein diameter in response to phenylephrine, acetylcholine (endothelium-dependent vasodilation) and sodium nitroprusside (endothelium-independent vasodilation).


RESULTS
Age, systolic blood pressure (No-Ins: 129.4 mmHg ± 11.8 mmHg, Ins: 134.8 mmHg ± 12.0 mmHg; P= 0.257), HbA1c, lipids and urinary albumin excretion rate [No-Ins: 9 mg/24 h (0-14.1 mg/24 h) vs. Ins: 10.6 mg/24 h (7.5-14.4 mg/24 h), P=0.398] were similar between groups. There was no difference between endothelium-dependent vasodilation of the No-Ins group (59.3% ± 26.5%) vs. the Ins group (54.0% ± 16.3%; P=0.526). Endothelium-independent vasodilation was also similar between the No-Ins (113.7% ± 35.3%) and Ins groups (111.9% ± 28.5%; P=0.888).


CONCLUSIONS
Subcutaneous insulin therapy does not interfere with venous endothelial function in type 2 diabetes when glycemic and blood pressure control are stable.
Departamento de Fisioterapia e Reabilitação, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil.
Antônio Marcos Vargas da
AM
Silva
Luciana de Moraes
Lde M
Penno
Marcello Casaccia
MC
Bertoluci
Maria Cláudia
MC
Irigoyen
Beatriz D'Agord
BD
Schaan
D000368:Aged; D001794:Blood Pressure / Q000187:drug effects; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy* / Q000503:physiopathology; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000502:physiology; D005260:Female; D006801:Humans; D007004:Hypoglycemic Agents / Q000494:pharmacology*; D007328:Insulin / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D018709:Statistics, Nonparametric; D014664:Vasodilation / Q000187:drug effects*
D007004:Hypoglycemic Agents; D007328:Insulin
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