SG SHERIDAN, Department of Anthropology, University of Notre Dame, Notre Dame, IN  46556

Numerous investigations of cribra orbitalia and iron-deficiency anemia have established a compelling case for chronic anemia among infants and children at the ancient Nubian site of Kulubnarti in northern Sudan.  The relationship among adults however, remains obscure.  An early elemental analysis of iron in hair showed no differences among adults with and without the lesion. This was interpreted as possibly indicating an amelioration of the anemia following childhood. However, it has also been argued that cribra orbitalia represents a skeletal response to nutritional anemia that is limited to childhood, even if the anemia is not.  Accordingly, a reduction in the lesion may reflect a shift in skeletal response to anemia rather than an abatement of the anemia itself.

To test whether iron deficiency anemia was present among the Kulubnarti adults, Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) was used to determine iron concentrations in femoral midshaft samples from 60 individuals aged 18 thru 51+ years.  Quality of bone preservation and degree of diagenesis were analyzed using multiple criteria.

Iron levels in those with and without the lesion were tested to determine if cribra orbitalia was a useful measure of nutritional anemia through the adult years. No significant differences were found, implying that either the anemia had abated, or that cribra orbitalia no longer serves as a monitor for anemia in adulthood.  Male/female differences in iron levels between those with and without the lesion also showed no significant differences (p=0.74).

However, when iron levels were regressed on age for each sex, striking differences appeared.  Male iron levels in young adults began at approximately 40 ppm and decreased insignificantly with age (p=0.45).  In contrast, young female (20-25 yrs) levels began at about 14 ppm, and significantly increased with age (p=0.038).  By age 50+ they reached the male levels of approximately 40 ppm.

This pattern becomes interpretable when the female regressions are compared to an archetypal fertility curve. Female iron values are lowest during the estimated peak fertility years (20-34), and increase as fertility diminishes.  By the postmenopausal years, female iron levels reach but never exceed male levels.

Low iron concentrations among reproductive-aged females is a likely result of iron-deficiency anemia exacerbated by the nutritional demands of menstruation, pregnancy, and lactation.  While no skeletal manifestations of this anemia are found in the Kulubnarti adults, elemental analysis provides the means for assessing this condition in adulthood.