Cross-sectional association of serum phosphate with carotid intima-medial thickness in hemodialysis patients.
BACKGROUND
Although an increased serum phosphate concentration is a significant risk factor for vascular calcification, it is unclear whether serum phosphate level is a risk factor for increased arterial wall thickness in hemodialysis patients.


METHODS
Using B-mode ultrasonography, we examined intima-medial thickness (IMT) of the carotid artery of hemodialysis patients and analyzed risk factors for increased IMT with regard to the effect of serum phosphate. Seven hundred sixteen hemodialysis patients were enrolled (547 patients without diabetes, 169 patients with diabetes; 441 men, 275 women; age, 60 +/- 8.5 years).


RESULTS
IMT of patients with diabetes was significantly greater than that of patients without diabetes (0.859 +/- 0.250 versus 0.783 +/- 0.178 mm; P < 0.0001). For the group of all patients, IMT correlated weakly, but significantly, with serum phosphate level (r = 0.093; P = 0.0127). In multiple regression analysis of the group of all patients, greater serum phosphate level (beta = 0.166; P < 0.0001) was shown to be a significant independent risk factor for increased carotid IMT, in addition to other significant independent risk factors, including advanced age, higher blood pressure, greater non-high-density lipoprotein cholesterol level, and the presence of diabetes (R2 = 0.1119; P < 0.00001). In multiple regression analyses performed separately for hemodialysis patients without and with diabetes, greater phosphate level and advanced age were significant independent risk factors for increased IMT, independent of other confounding risk factors.


CONCLUSIONS
These results show that in addition to advanced age, greater serum phosphate level is a significant and independent factor associated with advanced arteriosclerosis in hemodialysis patients with and without diabetes, suggesting that phosphate levels should be controlled appropriately to prevent an increase in arterial wall thickness in hemodialysis patients.
Ishimura
Eiji
E
Department of Nephrology, Osaka City University Graduate School of Medicine, Osaka, Japan. ish@med.osaka-cu.ac.jp
Taniwaki
Hiromichi
H
Tabata
Tsutomu
T
Tsujimoto
Yoshihiro
Y
Jono
Shuichi
S
Emoto
Masanori
M
Shoji
Tetsuo
T
Inaba
Masaaki
M
Inoue
Takashi
T
Nishizawa
Yoshiki
Y
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002339:Carotid Arteries / Q000000981:diagnostic imaging / Q000648:ultrastructure*; D002340:Carotid Artery Diseases / Q000453:epidemiology / Q000473:pathology*; D015897:Comorbidity; D003430:Cross-Sectional Studies; D048909:Diabetes Complications / Q000097:blood / Q000453:epidemiology / Q000473:pathology; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D007676:Kidney Failure, Chronic / Q000097:blood* / Q000453:epidemiology / Q000473:pathology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D010710:Phosphates / Q000097:blood*; D011446:Prospective Studies; D006435:Renal Dialysis; D012907:Smoking / Q000097:blood / Q000453:epidemiology; D017539:Tunica Intima / Q000000981:diagnostic imaging / Q000648:ultrastructure*; D017540:Tunica Media / Q000000981:diagnostic imaging / Q000648:ultrastructure*; D014463:Ultrasonography
D010710:Phosphates