Hemoglobin comparisons between AfricanAmerican and EuropeanAmerican males with hemoglobin values in

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Hemoglobin comparisons between African-American
and European-American males with hemoglobin
values in the normal range

• Ginette A. Hinds
• 03/22/2000

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Rationale

• To compare the Hb levels of healthy EA and AA
  males with Hb values in the normal range, and to
  determine whether the differences were
  significant enough to warrant the use of separate
  standards.

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The Study

• The sample chosen for this study included
• 2394 EA males and
• 303 AA males
• all 18 - 49 yrs old
• (since adult males tend to have a lower
• prevalence of iron deficiency- which is an
• important determinant in low Hb levels).

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Hematological Indicators Investigated

• Hemoglobin concentration
• Hematocrit
• Transferrin Saturation.
• Dietary information
• a 24-hour recall
• a 3-month food frequency questionnaire
• dietary supplement forms.

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Hemoglobin Concentration

• A measure of the volume of hemoglobin in a whole
  blood sample
• Avg. for men is 14-18 g/dL
• Lower limit for men is 13 g/dL (WHO) or 14g/dL
  (US)

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Hematocrit

• The volume of whole blood that is occupied by
  RBCs
• Avg. for men is 45-49
• Below Normal is lt39 (WHO) and lt42(US)

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Transferrin Saturation

• Transferrin is the transport protein for iron
• Saturation is a measure of the of transferrin
  that is bound to iron.
• Normal is gt33

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Table 1
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ResultsTable 1

• Shows Hb, Hct, TS, and Vit. C Fe intakes in AA
  and EA males
• There is a difference between mean Hb values of
  0.72 g
• There is differences in Hct of 0.77
• There is a difference in TS 0f 0.32.
• Note that EAs also had a higher iron intake
  (probably due to socioeconomic factors).

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Table 2
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ResultsTable 2

• Table 2 shows the cumulative distribution of Hb
  values in both races.
• There was a greater concentration of low Hb
  levels for AAs.
• almost 8 AA, but only O.8 EA below the WHO
  cutoff of 13g/dl.
• over 26 AA had Hb values below the US cutoff of
  14g/dl, compared to only 8.5 EA.
• 94 of EAs and 91 of AAs had Hb values in the
  normal range of 13 17g/dL
• Thus, 3 fewer AA had normal Hbs than EA.

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Table 3
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ResultsTable 3

• Shows the mean Hb values in AA and EA males at Hb
  levels above 13 g/dL
• The difference between the two means decreased as
  males with higher Hbs were compared.

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DiscussionProblems with the study

• a 24-hour recall questionnaire was used.
• not be a good representation of a typical
  day-to-day intake, and can lead to
  misclassification of individuals based on
  nutrient intake.
• Race classification.
• Individuals were classified according to
  external appearance (phenotype).

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Possible explanations for the lower prevalence of
normal Hb levels in AA

• Higher incidence of Hb lowering diseases
• Lower intake of hemopoietic nutrients.
• Lower ferritin saturation

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Conclusion

• Differences between AA and EA Hb values are
  almost exclusively at the lower values.
• It is highly likely that the following are
  responsible
• nutritional status
• a higher prevalence of alpha and beta
  thalassemias, hemoglobinopathies, and/or anemia
  of chronic disease in AAs

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Conclusion

• The researchers therefore conclude that a single
  Hb standard for both ethnic groups should be
  maintained until further research into the
  genetic facet of the argument against it is done.