Table 1.
Characteristics of the populations studied
| Characteristic | All women | Women without either inflammation, Plasmodium infection, or HIV infection | ||
|---|---|---|---|---|
| n | 470 | 175 | ||
| Age | ||||
| <20 years | 20.6% | (97) | 17.1% | (30) |
| ≥20 years | 79.4% | (373) | 82.9% | (145) |
| Gestational age | ||||
| 13–14 weeks | 9.1% | (43) | 6.3% | (11) |
| 15–16 weeks | 25.7% | (121) | 25.1% | (44) |
| 17–18 weeks | 29.6% | (139) | 26.3% | (46) |
| 19–21 weeks | 24.5% | (115) | 30.3% | (53) |
| 22–25 weeks | 11.1% | (52) | 12.0% | (21) |
| Gravidity | ||||
| Primigravida | 18.1% | (85) | 17.7% | (31) |
| Secundigravida | 19.6% | (92) | 16.0% | (28) |
| Multigravida | 62.3% | (293) | 66.3% | (116) |
| Plasma CRP concentration, mg/L | 4.3 | [2.1–10.4] | 0 | |
| Plasma AGP concentration, g/L | 0.72 | [0.60–0.93] | 0 | |
| Inflammation | ||||
| Plasma CRP concentration ≥10 mg/L | 26.8% | (126) | 0 | |
| Plasma AGP concentration ≥1 g/L | 18.1% | (85) | 0 | |
| Plasma concentrations of CRP ≥10 mg/L, or AGP ≥1.0 g/L | 32.3% | (152) | 0 | |
| HIV infection | 21.1% | (99)a | 0 | |
| Plasmodium infection | ||||
| Any Plasmodium infection,b by dipstick or PCR | 37.2% | (175) | 0 | |
| Current or recent P. falciparum infection, by either HRP2- or pLDH-based dipstick | 19.5% | (91) | 0 | |
| P. falciparum, by PCR | 34.7% | (163) | 0 | |
| Haemoglobin concentration, g/L | 113.2 | (11.4) | 115.7 | (10.8) |
| Anaemia (haemoglobin concentration <110 g/L) | 37.2% | (175) | 25.7% | (45) |
| Plasma ferritin concentration, μg/L | 13.9 | [8.2–29.2] | 10.6 | [7.0–18.5] |
| Iron status | ||||
| Iron deficient (plasma ferritin concentration <15 μg/L) | 52.8% | (248) | 64.6% | (113) |
| Iron replete (plasma ferritin concentration ≥15 μg/L, without inflammation) | 27.2% | (128) | 35.4% | (62) |
| Uncertain (plasma ferritin concentration ≥15 μg/L, with inflammation) | 20.0% | (94) | 0 | |
| Whole blood ZPP, μmol/mol haem | 90 | [68–121] | 87 | [63–121] |
| Whole blood ZPP >70 μmol/mol haem | 73.4% | (345) | 69.1% | (121) |
| Erythrocyte ZPP, μmol/mol haem | 36 | [20–66] | 42 | [20–74] |
| Erythrocyte ZPP >70 μmol/mol haem | 23.4% | (110) | 28.6% | (50) |
| Erythrocyte ZPP >40 μmol/mol haem | 46.4% | (218) | 52.6% | (92) |
| EP concentration, μg/L | 203 | [117–428]a | 224 | [130–476]c |
| Plasma sTfR concentration, mg/Ld | 1.94 | [1.48–2.63] | 1.87 | [1.36–2.62] |
| Plasma transferrin concentration, g/L | 3.12 | (0.56) | 3.21 | (0.54) |
| Plasma folate concentration, μg/Le | 6.91 | [5.45–9.39]f | 6.55 | [5.21–8.87]c |
| Plasma folate concentration <3 μg/L | 0.6% | (3/466)f | 0.6% | (1/174)c |
| Plasma vitamin B12 concentration, pmol/Lg | 425 | [311–651]f | 413 | [307–638]c |
| Plasma vitamin B12 concentration <150 pmol/L | 0.9% | (4/466)f | 0.6% | (1/174)c |
| Plasma bilirubin concentration, μmol/L | 6.9 | [4.9–9.4]f | 7.1 | [4.8–9.4]c |
| α +-thalassaemia genotype | ||||
| Normal | 51.2% | [109/213]h | 48.4% | [44]i |
| Heterozygote | 41.3% | [88/213]f | 42.9% | [39]i |
| Homozygote | 7.5% | [16/213]f | 8.8% | [8]i |
Values indicate mean (SD), median [25th and 75th percentile] or % (n).
AGP, α 1-acid glycoprotein protein; CRP, C-reactive protein; EP, Erythrocyte protoporphyrin; HRP2, P. falciparum-specific histidine-rich protein-2; pLDH, Plasmodium-specific lactate dehydrogenase; sTfR, Soluble transferrin receptor; ZPP:H, Zinc protoporphyrin:haem.
aMissing values resulted in n =468; bOnly one participant had infection by a Plasmodium species other than P. falciparum; cMissing values resulted in n =174; Reference values d0.8 1.9 mg/L and e2.6 15.4 μg/L; fMissing values resulted in n =466; Reference values g130 700 pmol/L; Missing values resulted in hn =213 and in =91.