Table 3.
Anemia and Iron Biomarkers at First Antenatal Visit and at End Assessment in Nonpregnant Nulliparae
| Endpoint | No. | Iron | Controla | Effectb | P Value | Adjusted Effectc | Adjusted P Value |
|---|---|---|---|---|---|---|---|
| ANC1 | |||||||
| Mean hemoglobin, g/dL | 314 | 10.17 [9.96–10.38] (1 missing) |
10.22 [9.99–10.46] | –0.06 [–.36 to .25] | .722 | –0.01 [–.32 to .3] | .944 |
| Anemiad | 314 | 112/162 (69.1) [61.6–75.7] | 107/152 (70.4) [62.7–77.1] | 0.98 [.85–1.14] | .902 | 0.96 [.83–1.10] | .524 |
| Severe anemiae | 314 | 2/162 (1.2) [.3–4.4] | 4/152 (2.6) [1.0–6.6] | 0.469 [.087–2.524] | .435 | 0.443 [.082–2.401] | .343 |
| Iron deficiency (%) (adjusted ferritin)f | 310 | 11/160 (6.9) [3.9–11.9] | 19/150 (12.7) [8.3–18.9] | 0.54 (.27–1.10) | .123 | 0.53 (.26–1.09) | .083 |
| Iron deficiency (%) (sTfR/log ferritin ratio)g | 312 | 18/162 (11.1%) [7.1–16.9] | 19/150 (12.7%) [8.3–18.9] | 0.88 (.48–1.61) | .728 | 0.84 (.46–1.54) | .578 |
| Mean ferritin, µg/L | 313 | 91 [78–107] (1 missing) | 87 [74–103] (1 missing) | 1.05 [.84–1.31] | .694 | 1.07 [.86–1.33] | .563 |
| Mean sTfR, mg/L | 313 | 6.0 [5.6–6.4] (1 missing) | 5.9 [5.6–6.3] (1 missing) | 1 [.91–1.1] | .949 | 1 [.91–1.1] | .962 |
| Mean ZPP, µmol/mol heme | 285 | 105 [100–111] (14 missing) | 106 [101–112] (16 missing) | 0.99 [.92–1.07] | .841 | 0.99 [.92–1.07] | .857 |
| Mean hepcidin, nmol/L | 311 | 3.01 [2.5–3.7] (3 missing) | 2.86 [2.3–3.5] (1 missing) | 1.05 [.79–1.41] | .729 | 1.07 [.80–1.43] | .664 |
| Elevated hepcidin, >10.5 nM/Lh | 311 | 29/160 (18.1) [12.9–24.8] | 25/151 (16.6) [11.5–23.3] | 1.09 (.67–1.78) | .766 | 1.12 (.69–1.83) | .649 |
| Nonpregnant | |||||||
| Mean hemoglobin, g/dL | 913 | 12.02 [11.91–12.12] (1 missing) | 11.93 [11.82–12.04] (2 missing) |
0.09 [–.07 to .24] | .261 | 0.06 [–.09 to .22] | .420 |
| Anemiai | 913 | 179/440 (40.7) [36.2–45.3] | 217/473 (45.9) [41.4–50.4] | 0.89 [.76–1.03] | .124 | 0.90 [.78–1.05] | .168 |
| Severe anemiaj | 913 | 0/440 (0.0) [0.0–0.9] | 3/473 (0.6) [0.2–1.8] | NA | .250 | NA | .996 |
| Iron deficiency (%) (adjusted ferritin)f | 910 | 38/439 (8.7) [6.4–11.7] | 50/471 (10.6) [8.1–13.7] | 0.82 [.55–1.22] | .369 | 0.82 [.55–1.23] | .336 |
| Iron deficiency (sTfR/log ferritin ratio)g | 909 | 89/437 (20.4) [16.9–24.4] | 97/472 (20.6) [17.2–24.4] | 0.99 [.77–1.28] | 1.000 | 0.99 [.77–1.28] | .960 |
| Mean ferritin, µg/L | 912 | 49 [46–53] (2 missing) | 51 [47–55] (2 missing) | 0.97 [.87–1.09] | .632 | 0.97 [.86–1.08] | .564 |
| Mean sTfR, mg/L | 909 | 6.4 [6.1–6.6] (4 missing) | 6.5 [6.2–6.7] (3 missing) | 0.98 [.94–1.04] | .558 | 0.98 [.93–1.04] | .534 |
| Mean ZPP, µmol/mol heme | 914 | 101 [97–104] (1 missing) | 101 [98–105] (1 missing) | 0.99 [.94–1.04] | .783 | 0.99 [.94–1.04] | .784 |
| Mean hepcidin, nmol/L | 909 | 2.85 [2.5–3.2] (3 missing) | 2.83 [2.5–3.2] (4 missing) | 1.01 [.86–1.17] | .939 | 1.0 [.86–1.17] | .960 |
| Elevated hepcidin, >10.5 nM/Lh | 909 | 70/438 (16.0) [12.8–19.7] | 72/471 (15.3) [12.3–18.8] | 1.05 [.77–1.41] | .785 | 1.05 [.78–1.43] | .736 |
Values in square brackets indicate the 95% confidence interval (CI).
Abbreviations: ANC1, first antenatal visit; NA, not applicable; sTfR, serum transferrin receptor; ZPP, zinc protoporphyrin.
aData are presented as No. (%) for binary variables, mean [95% CI] for hemoglobin; geometric mean [95% CI] for iron biomarkers.
bRisk ratio for binary outcomes; difference between arms for hemoglobin; ratio between arms for iron biomarker levels.
cAnemia measures adjusted for baseline menarche, season at assessment, and use of antimalarials in the previous month. Iron measures adjusted for baseline menarche.
dHemoglobin <11 g/dL.
eHemoglobin <8 g/dL.
fFerritin <15 µg/L if C-reactive protein (CRP) <10 mg/L or ferritin <70 µg/L if CRP ≥10 mg/L.
gRatio: sTfR µg/L to log10 ferritin >5.6.
hHepcidin 95% reference range for women aged 18–24 years from reference Dutch population was median 2.6 nM; 2.5th percentile 0.7 nm; and 97.5th percentile 10.5 nM [15].
iHemoglobin <12 g/dL.
jHemoglobin <7 g/d.