Plasma levels of adrenomedullin, a vasoactive peptide, in type 2 diabetic patients with and without retinopathy.
OBJECTIVE
The aim of this study was to investigate whether adrenomedullin (AM) secretion is modified in type 2 diabetic patients with and without retinopathy.


METHODS
The study was performed on 92 patients with type 2 diabetes, 65 of whom had uncomplicated diabetes, 27 had retinopathy, and 40 had mild to moderate hypertension. Patients with serum creatinine levels >1.2 mg/dL, were excluded. Circulating AM was assayed using a specific radioimmunoassay.


RESULTS
AM concentrations were significantly higher in type 2 diabetic patients (25+/-2.1 pg/mL) than in the 31 normal subjects (11+/-0.8 pg/mL) (P<0.001). Type 2 diabetic patients with retinopathy had significantly greater AM levels (30.8+/-3.4 pg/mL) than both controls (P<0.001) and type 2 diabetic patients without retinopathy (25.2+/-2 pg/mL same as previous value) (P<0.001). No statistical difference was found between diabetic patients with pre-proliferative retinopathy (27.3+/-4.7 pg/mL) and proliferative retinopathy (24+/-3.1 pg/mL) (P=0.543). In type 2 diabetic patients, a significant correlation between plasma AM levels and HbA1c values (r=0.467; P<0.01) was found.


CONCLUSIONS
Our findings indicate that circulating AM is increased in type 2 diabetic patients and that increase correlates with poor glucose metabolic control and presence of retinopathy.
Caliumi
C
C
Department of Clinical Sciences, University of Rome La Sapienza, Rome, Italy.
Balducci
S
S
Petramala
L
L
Cotesta
D
D
Zinnamosca
L
L
Cianci
R
R
Di Donato
D
D
Vingolo
E M
EM
Fallucca
F
F
Letizia
C
C
D053607:Adrenomedullin / Q000097:blood*; D000368:Aged; D015415:Biomarkers / Q000097:blood; D016022:Case-Control Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood*; D003930:Diabetic Retinopathy / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011863:Radioimmunoassay / Q000379:methods; D014665:Vasodilator Agents / Q000097:blood*
D015415:Biomarkers; D014665:Vasodilator Agents; D053607:Adrenomedullin