Table 2.
Malaria at First Antenatal Visit and at End Assessment in Nonpregnant Nulliparae
| Endpoint | Iron | Control | Ratio | P Value | Adjusted Ratio | Adjusted P Valuea |
|---|---|---|---|---|---|---|
| Prevalence: ANC1 | ||||||
| No. | 163 | 152 | ||||
| RDT positive, No. (%) | 95/161 (59.0) [51.3–66.3] | 89/152 (58.6) [50.6–66.1] | 1.01 [.84–1.21] | 1.000 | 1.00 [.98–1.03] | .718 |
| RDT positive and fever, No. (%) | 15/163 (9.2) [5.7–14.6] | 6/152 (3.9) [1.8–8.3] | 2.33 [.93–5.85] | .072 | 2.30 [.91–5.79] | .075 |
| Microscopy positiveb, No. (%) | 86/161 (53.4) [45.7–61.0] | 84/152 (55.3) [47.3–62.9] | 0.97 [.79–1.18] | .820 | 1.00 [.97–1.03] | .975 |
| Clinical malariac, No. (%) | 9/161 (5.6) [3.0–10.3] | 4/152 (2.6) [1.0–6.6] | 2.12 [.67–6.75] | .259 | 2.14 [.68–6.76] | .194 |
| Parasite density, parasites/mm3, GM | 2000 [1483–2696] | 2244 [1674–3008] | 0.89 [.59–1.35] | 0.585 | 0.89 [.58–1.36] | .584 |
| Prevalence: end assessmenta | ||||||
| No. | 441 | 475 | ||||
| RDT positive & fever, No. (%) | 19/432 (4.4) [2.8–6.8] | 30/464 (6.5) [4.6–9.1] | 0.68 [.39–1.19] | .188 | 0.69 [.39–1.21] | .193 |
| Microscopy positiveb, No. (%) | 189/441 (42.9) [38.3–47.5] | 186/474 (39.2) [34.9–43.7] | 1.09 [.93–1.28] | .282 | 1.10 [.95–1.28] | .180 |
| Clinical malariac, No. (%) | 13/440 (3.0) [1.7–5.0] | 22/474 (4.6) [3.1–6.9] | 0.64 [.32–1.25] | .228 | 0.67 [.34–1.31] | .237 |
| Parasite density, parasites/mm3, GM | 302 [248–368] | 316 [259–386] | 0.96 [.72–1.27] | .754 | 0.96 [.73–1.27] | .793 |
| Incidence to end assessment in nonpregnantd | ||||||
| Person-years of follow-up (No.) | 1114.9 (936) | 1121.1 (942) | ||||
| RDT positive (no./No.) | 0.40 (445/1115) | 0.40 (444/1121) | 1.01 [.88–1.15] | .908 | 1.01 [.89–1.15] | .867 |
| RDT positive and fever (no./No.) | 0.16 (174/1115) | 0.17 (188/1121) | 0.93 [.76–1.14] | .494 | 0.94 [.76–1.15] | .525 |
| Microscopy positive (no./No.) | 0.25 (282/1115) | 0.26 (286/1121) | 0.99 [.84–1.17] | .919 | 1.00 [.85–1.18] | .971 |
| Clinical malariac (no./No.) | 0.07 (79/1115) | 0.08 (87/1121) | 0.91 [.67–1.24] | .558 | 0.92 [.68–1.25] | .582 |
| Proportion infected in first yeare | ||||||
| No. at risk | 978 | 976 | ||||
| No. censored at 1 y (%) | 294 (30.1) | 294 (30.1) | ||||
| RDT positive and fever, % | 13 [11–15] | 14 [12–16] | 0.89 [.72–1.11] | .295 | 0.91 [.73–1.13] | .386 |
| Clinical malariac, % | 6 [5–8] | 7 [5–8] | 0.92 [.67–1.25] | .588 | 0.92 [.68–1.26] | .617 |
Values in square brackets indicate the 95% confidence interval.
Abbreviations: ANC1, first antenatal visit; GM, geometric mean; RDT, rapid diagnostic test.
aPrevalence adjusted for season at visit date, bed net use up to visit date, antimalarial use in month prior to visit, and menarcheal status at baseline. Ratio is risk ratio for iron treatment.
bParasite positive on blood smear.
c Plasmodium falciparum blood smear positive and fever ≥37.5°C.
dIncidence per person-year adjusted for weekly bed net adherence and menarcheal status at baseline; ratio is incidence ratio.
eCox regression model of time to first malaria episode, adjusted for baseline iron deficiency (ferritin), bed net use over observation time, visit, and menarcheal status at baseline, and stratified by enrollment month; ratio is hazard ratio.