Elevated plasma endothelin-1 levels in diabetes mellitus.
BACKGROUND
This study compares plasma endothelin-1 (ET-1) levels in patients with diabetes mellitus or hypertension with healthy controls, and investigates whether ET-1 levels are correlated with glycemic control, metabolic parameters, and vascular complications.


METHODS
The study population consisted of 103 patients with type 1 diabetes, 124 patients with type 2 diabetes, 35 hypertensive patients without diabetes mellitus, and 99 controls.


RESULTS
Plasma ET-1 concentrations were significantly higher in patients with type 1 diabetes (0.28 +/- 0.34 fmol/mL, P =.001), type 2 diabetes (0.31 +/- 0.32 fmol/mL, P <.0001), and hypertension (0.35 +/- 0.26 fmol/mL, P <.0001) compared to controls (0.08 +/- 0.13 fmol/mL). Diabetic patients taking angiotensin converting enzyme (ACE) inhibitors had significantly lower plasma ET-1 levels than patients without (0.22 +/- 0.20 fmol/mL v 0.38 +/- 0.39 fmol/mL, P =.029). There were significant associations between ET-1 levels and age (r = 0.38, P <.05) and systolic blood pressure (BP) (r = 0.27, P <.05) in healthy controls. In diabetes we found only nonsignificant associations between ET-1 levels and age or vascular complications and a weak association between plasma ET-1 levels and glycemic control.


CONCLUSIONS
Patients with diabetes or hypertension have elevated ET-1 levels, but do not exhibit positive correlations between ET-1 levels and BP, which was observed in healthy controls. Increased ET-1 levels do not induce hypertension in diabetes, but were lower in diabetic patients taking ACE inhibitors compared to those without ACE inhibitors. There is no significant association between ET-1 levels and vascular complications. These findings suggest that the plasma ET-1 level is not a marker of endothelial dysfunction but changes in plasma ET-1 levels may precede vascular complications associated with hypertension and diabetes.
Schneider
Jochen G
JG
Department of Internal Medicine I, Ruprecht-Karls-University of Heidelberg, Bergheimer Strasse 58, D-69115 Heidelberg, Germany.
Tilly
Nicole
N
Hierl
Thomas
T
Sommer
Ulrike
U
Hamann
Andreas
A
Dugi
Klaus
K
Leidig-Bruckner
Gudrun
G
Kasperk
Christian
C
D000328:Adult; D000368:Aged; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use; D015992:Body Mass Index; D016022:Case-Control Studies; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000188:drug therapy / Q000503:physiopathology; D019332:Endothelin-1 / Q000097:blood*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood* / Q000188:drug therapy / Q000503:physiopathology; D008297:Male; D008875:Middle Aged
D000806:Angiotensin-Converting Enzyme Inhibitors; D019332:Endothelin-1