TABLE 1
FROM:
Evidence for a protective (synergistic?) effect of B-vitamins and omega-3 fatty acids on cardiovascular diseases
A de Bree, L I Mennen, S Hercberg and P Galan
BACK TO ARTICLETable 1. Intervention trials evaluating the effect of B-vitamins on the risk of cardiovascular diseases
| Reference | Subjects | Intervention and duration | Results | Quality score a |
|---|---|---|---|---|
| de Jong et al (1999) | 273 M+W with peripheral arterial disease (onset<56 y) |
Intervention: 5000  g folic acid/day and 250 mg vitamin B6/day | After a median follow-up of 20 months, the adjusted RR for recurrent CVD in the treatment group was 0.76 (95% CI=0.33–1.74) compared to the control group | 2 |
| Intervention group: 70 subjects with postmethionine load HHCY | Duration: 1–63 months | |||
| Controls: 162 subjects with no postmethionine load HHCY | ||||
| Vermeulen et al (2000a) | 224 M+W with atherothrombotic cerebrovascular disease (onset<56 y) |
Intervention: 5000 g folic acid/day and 250 mg vitamin B6/day | After a median follow-up of 57 months, the adjusted RR for recurrent CVD in the treatment group was 0.96 (95% CI=0.48–1.92) compared to the control group | 2 |
| Intervention group: 52 subjects with postmethionine load HHCY | Duration: 3–101 months | |||
| Controls: 151 subjects with no postmethionine load HHCY | ||||
| Hackam et al (2000) | 101 M with atherosclerotic vascular disease |
Intervention: Groups A and B:Until 1996: 5000 g folic acid/dayAfter 1996: 2500 g folic acid/day, 25 mg vitamin B6/day and 250 g vitamin B12/day | Mean duration of treatment before vitamin therapy in group A was 2.6 y, vitamin therapy was 1.8 y. Mean duration of treatment before vitamin therapy in group B was 2.7 y, vitamin therapy 1.6 y. Rate of progression of carotid plague before and after vitamin therapy, as determined by ultrasound, was decreased in both groups | 0 |
| No risk estimates are given, no adjustments are mentioned | ||||
Group A: 51 subjects with tHcy >14 mol/lGroup B: 50 subjects with tHcy  14 mol/l | Duration: Not indicated when folic acid (only) treatment was started. | |||
| Vermeulen et al (2000b) | 158 M+W, healthy siblings of patients with premature atherothrombotic disease | Random double-blind allocation to intervention (n=68) or placebo (n=66) groupIntervention: 5000 g folic acid/day and 250 mg vitamin B6/day | The adjusted RR for a decreased rate of abnormal exercise electrography tests (which is a measure of coronary atherosclerosis) in the treatment group was 0.38 (95% CI=0.06–2.27) compared to the control group (unadjusted RR=0.40, 95% CI=0.17–0.93) | 5 |
| Duration: 2 y | ||||
| Schnyder et al (2002) | 553 M+W with a successful angioplasty | Random double-blind allocation to intervention (n=272) or placebo (n=281) groupIntervention: 1000 g folic acid/day, 400 g vitamin B12/day, 10 mg vitamin B6/day | After a mean follow-up of 11 months (including 6 months of supplementation), the adjusted RR for target lesion revascularization in the treatment group was 0.61 (95% CI=0.41–0.95) | 5 |
| Duration: 6 months |
a Score between 0 and 5, a score of 5 indicates that the trial complied with all our quality criteria's (see methods section). M=men; W=women; HHCY=hyperhomocysteinemia; CVD=cardiovascular diseases; RR=relative risk; CI=confidence interval; tHcy=total plasma homocysteine concentration.
