Hepatic Storage Iron Concentrations in Different Population Groups

Abstract

The feasibility of assessing the iron nutrition of a population by determining the storage iron concentration in necropsy specimens of liver was explored. A statistical approach was used to evaluate the possible effects of certain nonnutritional factors. Analysis of data from 3,983 specimens originating from 18 different countries provided evidence concerning the effects of the cause of death, the sex, and the age of the individual at death upon the hepatic storage iron concentration. The validity of the approach was strengthened by the finding that there was no difference between the values in individuals dying of cardiovascular disease and those killed by acute trauma. This suggested that the inevitable selection in any sample of necropsy specimens did not necessarily invalidate the assessment of iron nutrition by this method. In subjects dying from malignant neoplasms, however, the figures were higher. This was presumably due to "trapping" of iron in the reticuloendothelial cells. Whatever the cause, it is apparent that the storage iron concentration in the liver gives a falsely high reflection of iron nutrition under such circumstances. The effect of age on storage iron concentrations was found to depend on the amount of available iron in the diet and on the sex. In males there was no correlation between age and hepatic iron concentrations, with the exception of the Bantu of southern Africa. The high dietary intake of iron in these peoples was reflected both by the high median hepatic storage iron concentrations and by an increase in the iron stores with aging. Storage iron concentrations similar to those in males were found in women over 50 years, whereas the values were significantly lower in those under 40 years. These findings were asscribed to the reduction in iron needs that occur in females following the menopause. After excluding observations shown to be distorted by disease and female reproductive demands, it was possible to make a number of comparisons between different countries. The lowest storage iron concentrations were found in subjects from India and New Guinea. In addition, it was noted that there were significant differences between the storage iron status of groups from different Western countries.