title: Azithromycin-containing intermittent preventive treatment in pregnancy affects gestational weight gain, an important predictor of birthweight in Papua New Guinea - an exploratory analysis.
abstract: In Papua New Guinea, intermittent preventive treatment with sulphadoxine-pyrimethamine and azithromycin (SPAZ-IPTp) increased birthweight despite limited impact on malaria and sexually transmitted infections. To explore possible nutrition-related mechanisms, we evaluated associations between gestational weight gain (GWG), enrolment body mass index (BMI) and mid-upper arm circumference (MUAC), and birthweight. We investigated whether the increase in birthweight associated with SPAZ-IPTp may partly be driven by a treatment effect on GWG. The mean GWG rate was 393 g/week (SD 250; n = 948). A 100 g/week increase in GWG was associated with a 14 g (95% CI 2.6, 25.4) increase in birthweight (P = 0.016). Enrolment BMI and MUAC also positively correlated with birthweight. SPAZ-IPTp was associated with increased GWG [58 g/week (26, 900), P < 0.001, n = 948] and with increased birthweight [48 g, 95% CI (8, 880), P = 0.019] when all eligible women were considered (n = 1947). Inclusion of GWG reduced the birthweight coefficient associated with SPAZ-IPTp by 18% from 44 to 36 g (n = 948), although SPAZ-IPTp was not significantly associated with birthweight among women for whom GWG data were available (P = 0.13, n = 948). One month post-partum, fewer women who had received SPAZ-IPTp had a low post-partum BMI (<18.5 kg m(-2) ) [adjusted risk ratio: 0.55 (95% CI 0.36, 0.82), P = 0.004] and their babies had a reduced risk of wasting [risk ratio 0.39 (95% CI 0.21, 0.72), P = 0.003]. SPAZ-IPTp increased GWG, which could explain its impact on birthweight and maternal post-partum BMI. Future trials of SPAZ-IPTp must incorporate detailed anthropometric evaluations to investigate mechanisms of effects on maternal and child health.
authors.affiliation: Department of Medicine, The University of Melbourne, Melbourne, Victoria, Australia.|Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research (PNG IMR), Goroka, Papua New Guinea.
authors.forename: Holger W
authors.initials: HW
authors.lastname: Unger
authors.affiliation: Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research (PNG IMR), Goroka, Papua New Guinea.
authors.forename: Regina A
authors.initials: RA
authors.lastname: Wangnapi
authors.affiliation: Vector Borne Diseases Unit, Papua New Guinea Institute of Medical Research (PNG IMR), Goroka, Papua New Guinea.
authors.forename: Maria
authors.initials: M
authors.lastname: Ome-Kaius
authors.affiliation: Department of Medicine, The University of Melbourne, Melbourne, Victoria, Australia.|Victorian Infectious Diseases Service, Melbourne Health, Melbourne, Victoria, Australia.
authors.forename: Philippe
authors.initials: P
authors.lastname: Boeuf
authors.affiliation: Infection and Immunity Division, Walter and Eliza Hall Institute of Medical Research (WEHI), Melbourne, Victoria, Australia.|Department of Medical Biology, University of Melbourne, Melbourne, Victoria, Australia.
authors.forename: Stephan
authors.initials: S
authors.lastname: Karl
authors.affiliation: Infection and Immunity Division, Walter and Eliza Hall Institute of Medical Research (WEHI), Melbourne, Victoria, Australia.|Department of Medical Biology, University of Melbourne, Melbourne, Victoria, Australia.|Barcelona Centre for International Health Research (CRESIB), Barcelona, Spain.
authors.forename: Ivo
authors.initials: I
authors.lastname: Mueller
authors.affiliation: Department of Medicine, The University of Melbourne, Melbourne, Victoria, Australia. sroger@unimelb.edu.au.|Victorian Infectious Diseases Service, Melbourne Health, Melbourne, Victoria, Australia. sroger@unimelb.edu.au.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Rogerson
mesh_terms: D000293:Adolescent; D000962:Antimalarials / Q000008:administration & dosage*; D017963:Azithromycin / Q000008:administration & dosage*; D001724:Birth Weight / Q000187:drug effects*; D015992:Body Mass Index; D004338:Drug Combinations; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007230:Infant, Low Birth Weight; D016014:Linear Models; D044342:Malnutrition / Q000453:epidemiology* / Q000517:prevention & control; D018811:Maternal Exposure; D015999:Multivariate Analysis; D009752:Nutritional Status; D010219:Papua New Guinea / Q000453:epidemiology; D011247:Pregnancy; D011739:Pyrimethamine / Q000008:administration & dosage; D012307:Risk Factors; D012959:Socioeconomic Factors; D013413:Sulfadoxine / Q000008:administration & dosage; D015430:Weight Gain / Q000187:drug effects*
chemical_list: D000962:Antimalarials; D004338:Drug Combinations; C001205:fanasil, pyrimethamine drug combination; D017963:Azithromycin; D013413:Sulfadoxine; D011739:Pyrimethamine
keywords: antibiotics; antimalarials; body mass index, intermittent preventive treatment in pregnancy; low birthweight; mid-upper arm circumference