Relationship of plasma alpha tocopherol to index of clinical severity in individuals with sickle cell anemia.

Several parameters of micronutrition related to antioxidant activity are reduced in individuals with sickle cell anemia (SCA). The data presented here suggest that vitamin E, specifically alpha tocopherol, has a significant correlation (r = -0.38, P < 0.04) with a retrospective survey of clinical events and a significant correlation with a prospective survey of clinical events (r = -0.42, P < 0.03). The survey of clinical events score takes into account important vaso-occlusive manifestations in SCA. Differences in plasma vitamin E levels explained about 15% of the variability in the clinical manifestations of SCA in the population studied. Previously reported data from our lab suggests that the differences in alpha tocopherol levels are not related to dietary intake. Vitamin E may play an important role in modulating the ability of sickle hemoglobin containing erythrocytes to produce vaso-occlusion. Alternatively, it may simply be a marker of disease activity. Studies are ongoing at our center to determine if the relationship of alpha tocopherol to clinical events is causal.