Peripheral vascular disease and serum phosphorus in hemodialysis: a nested case-control study.
BACKGROUND
Serum phosphorus (P) and the product of serum calcium x serum P (Ca x P), are frequently elevated in end-stage renal disease patients on maintenance hemodialysis (HD). Elevated P and Ca x P have been associated with vascular calcification in dialysis patients.


OBJECTIVE
[corrected] To examine the role of P and Ca x P as risk factors for incident peripheral vascular disease (PVD) in HD patients with pre-existing CVD.


METHODS
This nested case-control study is drawn from the 11 incident PVD events reported in the cohort of the Secondary prevention with antioxidants of cardiovascular disease in end-stage renal disease (SPACE): a randomized placebo-controlled trial. PVD was defined clinically and confirmed ultrasonographically. Each individual with a PVD event was matched for SPACE treatment group (vitamin E or placebo), age (in 4-year categories) and gender with two individuals who had no CVD end point during the follow-up period.


RESULTS
Serum P and Ca x P levels were significantly higher in PVD patients than in controls. In univariate logistic regression analysis, only serum P predicted PVD in this population (OR 2.02, 95% CI 1.07 - 3.81, p = 0.03). In multivariate analysis, adjustment was made for variables dissimilar by PVD status including underlying renal disease, diabetes, smoking, history of angina pectoris, prescription for vitamin D3, erythropoietin, calcium channel blockers and aspirin. In this model, serum P remained the only significant predictor of incident PVD (OR 2.4, 95% CI 1.01 - 5.74, p = 0.04).


CONCLUSIONS
Findings of the present study are consistent with a role for serum P and Ca x P in the pathogenesis of PVD in HD patients.
Boaz
M
M
Epidemiology Unit and Brunner Institute of Medical Research, Holon, Israel. mboaz8@yahoo.com
Weinstein
T
T
Matas
Z
Z
Green
Smetana
S
S
D000328:Adult; D000368:Aged; D002118:Calcium / Q000097:blood*; D002318:Cardiovascular Diseases / Q000097:blood / Q000209:etiology; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D016491:Peripheral Vascular Diseases / Q000097:blood* / Q000209:etiology; D010758:Phosphorus / Q000097:blood*; D006435:Renal Dialysis; D012307:Risk Factors
D010281:Parathyroid Hormone; D010758:Phosphorus; D002118:Calcium