G. Ferns et al., Cholesterol standardized plasma vitamin E levels are reduced in patients with severe angina pectoris, INT J EXP P, 81(1), 2000, pp. 57-62
Vitamin E, the major lipid soluble plasma antioxidant, has been reported to
be reduced in patients with coronary atherosclerosis. We have measured the
levels of plasma ol-tocopherol (the predominant form of plasma vitamin E)
in 128 patients with different reported degrees of angina.
Patients with mild to moderate angina (grades I or II (CSS score)) (n = 64)
, and patients with severe angina (grades III and IV) (n = 64) were recruit
ed from Cardiology Clinics in the U.K. Healthy controls (n = 33) and patien
ts with hyperlipidaemia (n = 28) were also recruited.
The groups of patients with angina did not differ significantly for mean ag
e (58 +/- 1.0 years vs. 59 +/- 1.0 years, respectively); sex distribution (
the M:F ratio was 48:16 and 46:18 for the respective groups); or prevalence
of smoking (12% vs. 9%), or hypertension (19% vs. 33%). Total cholesterol
levels were higher in the group with severe angina (5.9 +/- 0.16 mmol/l vs.
5.3 +/- 0.13 mmol/l P < 0.05). Absolute levels of plasma vitamin E were no
t significantly different between the angina subgroups (12.9 +/- 0.40 mg/l
for the mild-moderate angina group vs. 12.5 +/- 0.51 mg/l for the severely
affected group), but were positively correlated with plasma cholesterol con
centrations in each case (P < 0.001). The ratio between plasma vitamin E: t
otal cholesterol was significantly lower in the patients with severe angina
(mean 2.20 +/- 0.09 mg/mmol) vs. a mean value of 2.46 +/- 0.08 mg/m mot in
the mildly affected group (P < 0.05). The plasma vitamin E: total choleste
rol ratio in patients with severe angina was also significantly lower (P <
0.05) compared to either healthy controls with comparable total cholesterol
levels (n = 33), or hypercholesterolaemic subjects (n = 28) without sympto
matic coronary disease (mean ratios were 2.69 +/- 0.40 mg/mmol and 2.74 +/-
0.68 mg/mmol, respectively).
Vitamin E has previously been demonstrated to protect endothelial function
in the presence of hypercholesterolaemia, possibly by preserving nitric oxi
de bio-activity. It also inhibits LDL oxidation. Hence, a high plasma vitam
in E: total cholesterol ratio may be associated with an amelioration of ang
ina.