Dataset Information

Malaria, malnutrition, and birthweight: A meta-analysis using individual participant data.

ABSTRACT:

Background

Four studies previously indicated that the effect of malaria infection during pregnancy on the risk of low birthweight (LBW; <2,500 g) may depend upon maternal nutritional status. We investigated this dependence further using a large, diverse study population.

Methods and findings

We evaluated the interaction between maternal malaria infection and maternal anthropometric status on the risk of LBW using pooled data from 14,633 pregnancies from 13 studies (6 cohort studies and 7 randomized controlled trials) conducted in Africa and the Western Pacific from 1996-2015. Studies were identified by the Maternal Malaria and Malnutrition (M3) initiative using a convenience sampling approach and were eligible for pooling given adequate ethical approval and availability of essential variables. Study-specific adjusted effect estimates were calculated using inverse probability of treatment-weighted linear and log-binomial regression models and pooled using a random-effects model. The adjusted risk of delivering a baby with LBW was 8.8% among women with malaria infection at antenatal enrollment compared to 7.7% among uninfected women (adjusted risk ratio [aRR] 1.14 [95% confidence interval (CI): 0.91, 1.42]; N = 13,613), 10.5% among women with malaria infection at delivery compared to 7.9% among uninfected women (aRR 1.32 [95% CI: 1.08, 1.62]; N = 11,826), and 15.3% among women with low mid-upper arm circumference (MUAC <23 cm) at enrollment compared to 9.5% among women with MUAC ? 23 cm (aRR 1.60 [95% CI: 1.36, 1.87]; N = 9,008). The risk of delivering a baby with LBW was 17.8% among women with both malaria infection and low MUAC at enrollment compared to 8.4% among uninfected women with MUAC ? 23 cm (joint aRR 2.13 [95% CI: 1.21, 3.73]; N = 8,152). There was no evidence of synergism (i.e., excess risk due to interaction) between malaria infection and MUAC on the multiplicative (p = 0.5) or additive scale (p = 0.9). Results were similar using body mass index (BMI) as an anthropometric indicator of nutritional status. Meta-regression results indicated that there may be multiplicative interaction between malaria infection at enrollment and low MUAC within studies conducted in Africa; however, this finding was not consistent on the additive scale, when accounting for multiple comparisons, or when using other definitions of malaria and malnutrition. The major limitations of the study included availability of only 2 cross-sectional measurements of malaria and the limited availability of ultrasound-based pregnancy dating to assess impacts on preterm birth and fetal growth in all studies.

Conclusions

Pregnant women with malnutrition and malaria infection are at increased risk of LBW compared to women with only 1 risk factor or none, but malaria and malnutrition do not act synergistically.

SUBMITTER: Cates JE

PROVIDER: S-EPMC5549702 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Publications

Malaria, malnutrition, and birthweight: A meta-analysis using individual participant data.

Cates Jordan E JE Unger Holger W HW Briand Valerie V Fievet Nadine N Valea Innocent I Tinto Halidou H Tinto Halidou H D'Alessandro Umberto U Landis Sarah H SH Adu-Afarwuah Seth S Dewey Kathryn G KG Ter Kuile Feiko O FO Desai Meghna M Dellicour Stephanie S Ouma Peter P Gutman Julie J Oneko Martina M Slutsker Laurence L Terlouw Dianne J DJ Kariuki Simon S Ayisi John J Madanitsa Mwayiwawo M Mwapasa Victor V Ashorn Per P Maleta Kenneth K Mueller Ivo I Stanisic Danielle D Schmiegelow Christentze C Lusingu John P A JPA van Eijk Anna Maria AM Bauserman Melissa M Adair Linda L Cole Stephen R SR Westreich Daniel D Meshnick Steven S Rogerson Stephen S

PLoS medicine 20170808 8

<h4>Background</h4>Four studies previously indicated that the effect of malaria infection during pregnancy on the risk of low birthweight (LBW; <2,500 g) may depend upon maternal nutritional status. We investigated this dependence further using a large, diverse study population.<h4>Methods and findings</h4>We evaluated the interaction between maternal malaria infection and maternal anthropometric status on the risk of LBW using pooled data from 14,633 pregnancies from 13 studies (6 cohort studie ...[more]

PMID: 28792500

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Dataset Information

Malaria, malnutrition, and birthweight: A meta-analysis using individual participant data.

Background

Methods and findings

Conclusions

Publications

Malaria, malnutrition, and birthweight: A meta-analysis using individual participant data.

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