Characterization of premature atherosclerosis of carotid arteries in acromegalic patients.
OBJECTIVE
Acromegalic patients have increased mortality from vascular diseases. Although atherosclerotic risk factors such as hypertension, diabetes mellitus and dyslipoproteinaemia are highly associated with acromegaly, the prevalence of premature atherosclerosis in acromegalic patients and its relationship to these risk factors have not been reported.


METHODS
We measured mean intima-media thickness (IMT) of the carotid arteries in 21 acromegalic patients without symptomatic atherosclerotic vascular disease, by ultrasound high-resolution B-mode imaging. In analysis 1, it was compared with the predicted mean IMT based on data from existing risk factors (age, male sex, dyslipoproteinaemia, hypertension, diabetes mellitus, smoking status) in 282 non-acromegalic subjects. In analysis 2, the mean IMT in the 21 acromegalic patients was compared with that in 42 non-acromegalic subjects matched for age, sex and the other atherosclerotic risk factors. We also analysed clinical characteristics between the acromegalic patients with and without the atherosclerosis.


RESULTS
Mean IMT in 21 acromegalic patients was 0.92 +/- 0.21 (mean +/- SD) mm. It was significantly (P < 0.05) lower than the mean IMT (1.03 +/- 0.12 mm) predicted from their existing risk factors (analysis 1). It was also less than that in 42 non-acromegalic subjects matched for atherosclerotic risk factors (1.07 +/- 0.37 mm; P < 0.05) (analysis 2). Among the acromegalic patients, 10 patients (48%) had increased mean IMT (> or = 1.1 mm) and/or plaque lesions whereas the other 11 had no such atherosclerotic changes. In the patients without the atherosclerotic changes, plasma insulin-like growth factor-I (IGF-I) concentration was significantly (P < 0.01) higher, and the prevalence of hypertension was significantly (P < 0.05) lower than in those with the atherosclerotic changes.


CONCLUSIONS
The extent of carotid atherosclerosis in the acromegalic patients was not higher than that in non-acromegalic subjects, considering their atherosclerotic risk factors. Increased concentration of IGF-I might be involved in the lack of susceptibility to atherosclerosis in some acromegalic patients.
Otsuki
M
M
Department of Molecular Medicine, Osaka University Medical School (C-4), Osaka, Japan.
Kasayama
S
S
Yamamoto
H
H
Saito
H
H
Sumitani
S
S
Kouhara
H
H
Saitoh
Y
Y
Ohnishi
T
T
Arita
N
N
D000172:Acromegaly / Q000097:blood / Q000150:complications* / Q000000981:diagnostic imaging*; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002339:Carotid Arteries / Q000000981:diagnostic imaging*; D002340:Carotid Artery Diseases / Q000097:blood / Q000150:complications* / Q000000981:diagnostic imaging*; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D048909:Diabetes Complications; D005260:Female; D006801:Humans; D006951:Hyperlipoproteinemias / Q000150:complications; D006973:Hypertension / Q000150:complications; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012307:Risk Factors; D012737:Sex Factors; D012907:Smoking / Q000009:adverse effects; D017539:Tunica Intima / Q000000981:diagnostic imaging; D014463:Ultrasonography
D007334:Insulin-Like Growth Factor I