Table 3:

Effects of iron supplementation at 12 weeks on biological markers, by initial concentration of hemoglobin

VariableTreatment effect* 12 weeks – baseline (95%CI)p value, interaction term
Initial hemoglobin level < 13.0 g/dL
n = 49
Initial hemoglobin level ≥ 13.0 g/dL
n = 149
Hemoglobin, g/dL0.97 (0.54 to 1.40)0.09 (−0.22 to 0.41)< 0.001
Ferritin, μg/L8.4 (2.0 to 14.8)12.7 (7.5 to 17.9)0.4
Mean corpuscular volume, fL1.0 (−1.8 to 3.9)2.2 (0.9 to 3.5)0.4
Hematocrit, %2.3 (0.2 to 4.4)0.5 (−0.7 to 1.7)0.1
Transferrin, g/L−0.1 (−0.4 to 0.2)−0.2 (−0.4 to 0.03)0.5
Soluble transferrin receptor, mg/L−0.89 (−1.6 to −0.2)−0.4 (−0.6 to −0.1)0.05
Transferrin saturation, %2.5 (−5.7 to 10.7)3.8 (−1.7 to 9.2)0.8
  • Note: CI = confidence interval.

  • * A hot-deck method with 10 imputations was used to account for data that were missing and lost to follow-up.