NO - Besoin d'assistance

Observational epidemiological surveys (WG 3) page 58
_________________________________________________________________________________________
2-3-2 Vitamin E
Vitamin E is not judged to be a suitable proxy nutrient for fruit and vegetables intake. Several
groups have measured serum vitamin E levels in patients with CVD but there was no
consistent relationship with the presence or absence of disease (Tangney, 1997; Law and
Morris, 1998). The cohort studies involving dietary consumption of vitamin E either by food
or supplements are summarized in Table 33. The Nurses Health Study (Stampfer et al., 1993)
showed a significant reduction of non-fatal and fatal myocardial infarction in nurses regularly
taking vitamin E from dietary sources and supplements. Similar risk reductions were observed
in the Health Professionals Follow-up Study (Rimm et al., 1993) as an inverse correlation
between vit E and β-carotene intake and relative risk of CHD was found. In the Finnish study
(Knekt et al., 1994), significant coronary protection was observed only for women consuming
high amounts of vitamin E, but not in the Rotterdam study (Klipstein-Grobusch et al., 1999).
In the Iowa Women's Health study (Kushi et al., 1996-b), the reduction in risk from coronary
disease was in the group not taking supplements.
Three large intervention trials of vitamin E have been published (The ATBC study prevention
group, 1994; Blot et al, 1993; Stephens et al., 1996) and summarized in Table 34. In the
ATBC follow-up study, supplements of vit E (50 mg/day, a relatively low dose) had no effect
on cardiovascular deaths after 5-8 years of follow-up. In the Cambridge Heart Antioxidant
Study (CHAOS) of patients with evidence of angiogenic heart disease, (Stephens et al.,
1996), a large and significant reduction of nonfatal myocardial infarction was reported in the
vitamin E group (400 or 800 IU/day) compared to the placebo. No effect was seen on CVD
death or total mortality. The recent GISSI studies (GISSI-Prevenzione Investigators, 1999 and
HOPES, 2000) did not show a significant benefit of a supplementation of 300mg and 400
IU/day on overall survival. The Chinese Cancer Prevention Study (Blot et al., 1993) tested
combinations of 9 different micronutrients including vitamins A, C, E, beta-carotene.
Although statistically significant reductions in total mortality of 9% to 13% were seen, it
could not be attributed to any single nutrient.