Sulfadoxine-pyrimethamine resistance and intermittent preventive treatment during pregnancy: a retrospective analysis of birth weight data in the Democratic Republic of Congo (DRC).
OBJECTIVE
To assess the effect of intermittent preventive treatment with sulfadoxine-pyrimethamine (IPTp-SP) on birth weight in sites with varying degrees of drug resistance.


METHODS
Birth weight data from three regions in Democratic Republic of Congo with varying degrees of sulfadoxine-pyrimethamine (SP) resistance (1.6% in Mikalayi, 21.7% in Kisangani and 60.6% in Rutshuru) were analysed retrospectively by means of a logistic model that included the number of SP doses taken by the mother and other potentials confounding factors.


RESULTS
The IPTp-SP reduced the risk of low birth weight (LBW) in Kisangani (adjusted OR, 0.15; IC95%, 0.05-0.46) and in Mikalayi (adjusted OR, 0.12; IC95%, 0.01-0.89). In both sites, the average birth weight was higher for mothers having received two rather than one or no SP doses (P < 0.001). In Rutshuru, IPTp-SP had an effect in primigravidae but not in multigravidae. However, after adjustment for other LBW risk factors, there was no difference in the proportion of LBW (adjusted OR 0.92; IC95%, 0.37-2.25) between women having taken at least 2 SP doses and those with only one dose or none.


CONCLUSIONS
IPT-SP remains an effective strategy in Kisangani and Mikalayi where the therapeutic failure to SP in children with clinical malaria was 21.7% and 1.6%, respectively, while IPTp-SP effect seems lower in Rutshuru where the therapeutic failure to SP was 60.6%. The threshold value of SP resistance at which IPTp-SP fails to have a significant impact on birth weight and LBW is unknown. Considering that no alternative is currently available, additional studies on the efficacy of IPTp-SP in the areas of high SP resistance such as Rutshuru are needed so that the threshold at which this intervention fails to provide any benefit is determined with some precision.
Université Libre de Bruxelles, Brussels, Belgium. losimba@ulb.ac.be
Joris L
JL
Likwela
Umberto
U
D'Alessandro
Bernard L
BL
Lokwa
Sylvain
S
Meuris
Michele W
MW
Dramaix
D000293:Adolescent; D000328:Adult; D000962:Antimalarials / Q000008:administration & dosage / Q000009:adverse effects*; D001724:Birth Weight / Q000187:drug effects*; D003223:Congo; D004338:Drug Combinations; D004351:Drug Resistance; D005260:Female; D047109:Fetal Development / Q000187:drug effects*; D020073:Gravidity; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D016015:Logistic Models; D008288:Malaria / Q000517:prevention & control*; D011247:Pregnancy; D011256:Pregnancy Outcome; D011739:Pyrimethamine / Q000008:administration & dosage / Q000009:adverse effects*; D012189:Retrospective Studies; D012307:Risk Factors; D013413:Sulfadoxine / Q000008:administration & dosage / Q000009:adverse effects*; D055815:Young Adult
D000962:Antimalarials; D004338:Drug Combinations; C001205:fanasil, pyrimethamine drug combination; D013413:Sulfadoxine; D011739:Pyrimethamine