Introduction and objective. The incidence of myocardial infarction in
Spain is low in spite of the high prevalence of smoking and hypertensi
on. Natural antioxidants as vitamin E from a diet rich in fruit, oils
and vegetables may protect against the development of this disease. In
this study we have examine plasma levels of vitamin A and E as risk f
actors in the development of myocardial infarction. Study design. 62 c
ases were selected among patients 30-70 years old admitted to the hosp
ital with a first episode of myocardial infarction, or diagnosed by ar
teriography of coronary heart disease. 62 controls were selected among
patients with minor surgical conditions, and free of coronary heart d
isease according to the Rose questionnaire and ECG. Laboratory analysi
s. Plasma samples for vitamin assays were taken in the first 24 hours
after admission (62 cases) Plasma was separated by centrifugation and
stored at -80 degrees C until plasma vitamins were determined by HPLC.
Results. Lipid adjusted blood levels of vitamin E were lower in cases
, mean: 1092.0 +/- standard deviation 165.8 mu g/dl (mean +/- SD) than
in controls (1220.1 +/- 274.8 mu g/dl p = 0.002). The multivariate ad
justed odds ratio between extreme quintiles of blood vitamin E were 0.
06 (95% confidence intervals (CI): 0.01-0.5; p for trend 0.0027. Adjus
ted blood levels of vitamins A were also lower in cases 44.0 +/- 15.1
mu g/dl than in controls: (57.5 +/- 15.2 mu g/dl; p < 0.001). Adjusted
odds ratio between extreme quintiles of blood vitamin A adjusted for
confounding factors were 0.06 (95% CI: 0.01-0.36; p for trend < 0.0000
1). Conclusions. There is an association between acute of myocardial i
nfarction and reduce blood levels of vitamin A and E, that is not expl
ained by the decrement in blood lipids levels. Therefore low blood lev
els of fat soluble vitamins may be a risk factor for the development o
f this disease.