Plasma-vitamin E and low plasma lipoprotein levels in sickle cell anemia patients.

Increasing evidence suggests that in vivo lipid peroxidation may be an important factor in sickle cell anemia (HbSS). Vitamin E is the major lipid-soluble antioxidant in plasma, and this vitamin, as well as cholesterol, is transported in plasma almost exclusively by lipoproteins. The purpose of this investigation was to determine if vitamin E and plasma lipoprotein-cholesterol levels in sickle cell anemia (SCA) patients are interrelated. We found that low plasma-vitamin E levels in SCA patients were accompanied by low levels of plasma-cholesterol. The mean plasma-vitamin E/plasma-cholesterol ratio was similar in 12 SCA patients (6.1 +/- 0.7 micrograms vitamin E per mg plasma-cholesterol) and 21 controls (6.5 +/- 0.7 micrograms/mg). Our results suggest that the low levels of plasma-vitamin E in SCA patients may be related to decreased levels of lipoprotein carriers. The low plasma-cholesterol levels in SCA patients (139.1 +/- 9.9 mg/dL) were due to low levels of both high density lipoprotein-cholesterol (HDL-cholesterol of 35.0 +/- 1.0 mg/dL) and low density lipoprotein-cholesterol (LDL-cholesterol of 97.8 +/- 9.2 mg/dL). The "atherogenic index," defined as LDL-cholesterol/HDL-cholesterol, was similar in the SCA patients (2.9 +/- 0.2) and the controls (3.0 +/- 0.4).