THE SIZES OF THE EXCHANGEABLE POOLS OF SELENIUM IN ELDERLY WOMEN AND THEIR RELATION TO INSTITUTIONALIZATION

Exchangeable pools of Se after an intravenous injection of Se-74-enric hed isotope as sodium selenite were measured in two groups (n 9) of el derly women (free-living aged 64-82 years and institutionalized aged 6 8-82 years), and a comparison group (n 9) of young women aged 31-40 ye ars to evaluate the effect of age and institutionalization on Se reser ves. Dietary Se intake was not different among the three groups. Plasm a Se and glutathione peroxidase (EC 1.11.1.9) levels were significantl y lower in the institutionalized elderly women (P < 0.05). In each of the three groups, two pools were determined from our model. The size o f the first pool and the sum of the two pools were lower in the group of institutionalized elderly women than in the other two groups. The s ignificant correlation between plasma Se level and total Se pool size (r 0.66, P < 0.01) indicated that this last variable could serve as a new marker of Se status. Finally, these data suggest that the Se statu s of elderly women is more related to lifestyle, in terms of instituti onalization or not, than to age per se.