Atherosclerosis and folic acid supplementation trial in chronic renal failure: baseline results.
BACKGROUND
Atherosclerosis and Folic Acid Supplementation Trial (ASFAST) is a randomized placebo controlled trial assessing whether high-dose folic acid can reduce cardiovascular events and atherosclerosis progression in patients with chronic renal failure (CRF). Here we report the baseline results and compare indices of arterial structure (carotid intima-medial thickness (IMT)) and function (systemic arterial compliance (SAC)), pressure augmentation index (AI(x)) and pulse wave velocity (PWV a-f and PWV f-d)) to age- and sex-matched controls.


METHODS
Three hundred and fifteen subjects with CRF (serum creatinine > or = 0.40 mmol/L) aged 24-79 years (mean +/- SD: 56.6 +/- 13.6 years) and 213 healthy controls (58.2 +/- 10.2 years) were studied. Fasting blood samples were assayed for lipids (both groups), total homocysteine (tHcy), red cell folate, cobalamin and fibrinogen (CRF group). Ultrasound B mode measurements were used to determine mean carotid IMT and applanation tonometry techniques to determine SAC, AI(x), PWV (a-f), PWV (f-d) and central pressures.


RESULTS
Ninety-six per cent of the CRF group had at least one of: hypertension, hypercholesterolaemia, diabetes or smoking; 35% had established cardiovascular disease. The mean IMT was greater in CRF patients than in controls (0.86 +/- 0.19 vs 0.68 +/- 0.11 mm, P < 0.001). The SAC was significantly lower, and PWV (a-f) and AI(x) significantly higher. The tHcy was increased in 97% of the CRF group (27.3 +/- 2.9 micromol/L (normal < 13)). Total homocysteine did not correlate with IMT or any other measure of arterial function. However, those in the upper quantile of tHcy (> or =25 micromol/L) did have higher PWV (a-f) and lower SAC than those in the lower quantile.


CONCLUSIONS
Compared to normals, patients with CRF exhibited a 10-15-year shift to the right in age-related increases in carotid IMT and PWV (a-f), and significantly increased central pressure augmentation. This 5-year study is examining the impact of high-dose folic acid therapy on cardiovascular end-points, IMT progression and arterial function in CRF.
Zoungas
Sophia
S
Department of Vascular Sciences and Medicine, Monash University, Dandenong Hospital, Dandenong, Victoria, Australia. sophia.zoungas@med.monash.edu.au
Branley
Pauline
P
Kerr
Peter G
PG
Ristevski
Sonya
S
Muske
Christine
C
Demos
Lisa
L
Atkins
Robert C
RC
Becker
Gavin
G
Fraenkel
Margaret
M
Hutchison
Brian G
BG
Walker
Robert
R
McNeil
John J
JJ
McGrath
Barry P
BP
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001161:Arteriosclerosis / Q000097:blood / Q000209:etiology* / Q000517:prevention & control*; D005260:Female; D005492:Folic Acid / Q000627:therapeutic use*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood / Q000150:complications*; D008297:Male; D008875:Middle Aged
D005492:Folic Acid