Karen M O'Callaghan, Huma Qamar, Alison D Gernand, AK Onoyovwi, Stanley Zlotkin, Abdullah A Mahmud, Tahmeed Ahmed, Farhana K Keya, Daniel E Roth
{"title":"一项随机对照试验的二次分析:孕妇产前、产后或不产后补充维生素D3并不能改善分娩时孕妇的铁状态或6个月大时婴儿的铁状态","authors":"Karen M O'Callaghan, Huma Qamar, Alison D Gernand, AK Onoyovwi, Stanley Zlotkin, Abdullah A Mahmud, Tahmeed Ahmed, Farhana K Keya, Daniel E Roth","doi":"10.1136/bmjnph-2023-000758","DOIUrl":null,"url":null,"abstract":"Background Vitamin D may modify iron status through regulation of hepcidin and inflammatory pathways. This study aimed to investigate effects of maternal vitamin D supplementation on iron status in pregnancy and early infancy. Methods In a trial in Dhaka, Bangladesh, women (n=1300) were randomised to one of five vitamin D 3 regimens from 17 to 24 weeks’ gestation until 26 weeks postpartum (prenatal; postpartum doses): 0;0, 4200;0, 16 800;0, 28 000;0 or 28 000;28 000 IU/week. All participants received standard iron-folic acid supplementation. In this secondary analysis (n=998), we examined effects of prenatal;postpartum vitamin D on serum ferritin and other biomarkers of maternal iron status (transferrin saturation, total iron binding capacity, soluble transferrin receptor and hepcidin) at delivery, and infant ferritin and haemoglobin at 6 months of age. Using linear regression, we estimated per cent mean differences between each intervention group and placebo with 95% CIs, with and without adjustment for baseline ferritin or inflammatory biomarkers (C reactive protein and α-1-acid glycoprotein (AGP)). Results At delivery, ferritin concentrations were similar between each intervention group and placebo in unadjusted (n=998) and baseline ferritin-adjusted analyses (n=992; p>0.05). Compared with placebo, AGP was lower in each intervention group (per cent difference (95% CI) = −11% (−21 to –1.0), −14% (−23 to –3.5) and −11% (−19 to –2.0) in the 4200 IU/week, 16 800 IU/week and 28 000 IU/week groups, respectively; n=779). In the subgroup of women with baseline 25-hydroxyvitamin D < 30 nmol/L, ferritin was lower in each intervention group versus placebo (−23% (−37 to –5.0), −20% (−35 to –1.9) and −20% (−33 to –4.1) in the 4200 IU/week, 16 800 IU/week and 28 000 IU/week groups, respectively; n=645); effects were slightly attenuated after adjustment for inflammation (n=510). There were no effects of vitamin D on other iron biomarkers among women at delivery or infants aged 6 months. Conclusion These findings do not support improvement of iron status by vitamin D. The effect of prenatal vitamin D supplementation on ferritin may reflect an anti-inflammatory mechanism.","PeriodicalId":36307,"journal":{"name":"BMJ Nutrition, Prevention and Health","volume":null,"pages":null},"PeriodicalIF":3.3000,"publicationDate":"2023-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Maternal prenatal, with or without postpartum, vitamin D3 supplementation does not improve maternal iron status at delivery or infant iron status at 6 months of age: secondary analysis of a randomised controlled trial\",\"authors\":\"Karen M O'Callaghan, Huma Qamar, Alison D Gernand, AK Onoyovwi, Stanley Zlotkin, Abdullah A Mahmud, Tahmeed Ahmed, Farhana K Keya, Daniel E Roth\",\"doi\":\"10.1136/bmjnph-2023-000758\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Background Vitamin D may modify iron status through regulation of hepcidin and inflammatory pathways. This study aimed to investigate effects of maternal vitamin D supplementation on iron status in pregnancy and early infancy. Methods In a trial in Dhaka, Bangladesh, women (n=1300) were randomised to one of five vitamin D 3 regimens from 17 to 24 weeks’ gestation until 26 weeks postpartum (prenatal; postpartum doses): 0;0, 4200;0, 16 800;0, 28 000;0 or 28 000;28 000 IU/week. All participants received standard iron-folic acid supplementation. In this secondary analysis (n=998), we examined effects of prenatal;postpartum vitamin D on serum ferritin and other biomarkers of maternal iron status (transferrin saturation, total iron binding capacity, soluble transferrin receptor and hepcidin) at delivery, and infant ferritin and haemoglobin at 6 months of age. Using linear regression, we estimated per cent mean differences between each intervention group and placebo with 95% CIs, with and without adjustment for baseline ferritin or inflammatory biomarkers (C reactive protein and α-1-acid glycoprotein (AGP)). Results At delivery, ferritin concentrations were similar between each intervention group and placebo in unadjusted (n=998) and baseline ferritin-adjusted analyses (n=992; p>0.05). Compared with placebo, AGP was lower in each intervention group (per cent difference (95% CI) = −11% (−21 to –1.0), −14% (−23 to –3.5) and −11% (−19 to –2.0) in the 4200 IU/week, 16 800 IU/week and 28 000 IU/week groups, respectively; n=779). In the subgroup of women with baseline 25-hydroxyvitamin D < 30 nmol/L, ferritin was lower in each intervention group versus placebo (−23% (−37 to –5.0), −20% (−35 to –1.9) and −20% (−33 to –4.1) in the 4200 IU/week, 16 800 IU/week and 28 000 IU/week groups, respectively; n=645); effects were slightly attenuated after adjustment for inflammation (n=510). There were no effects of vitamin D on other iron biomarkers among women at delivery or infants aged 6 months. Conclusion These findings do not support improvement of iron status by vitamin D. The effect of prenatal vitamin D supplementation on ferritin may reflect an anti-inflammatory mechanism.\",\"PeriodicalId\":36307,\"journal\":{\"name\":\"BMJ Nutrition, Prevention and Health\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":3.3000,\"publicationDate\":\"2023-11-14\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"BMJ Nutrition, Prevention and Health\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1136/bmjnph-2023-000758\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"NUTRITION & DIETETICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"BMJ Nutrition, Prevention and Health","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1136/bmjnph-2023-000758","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"NUTRITION & DIETETICS","Score":null,"Total":0}
Maternal prenatal, with or without postpartum, vitamin D3 supplementation does not improve maternal iron status at delivery or infant iron status at 6 months of age: secondary analysis of a randomised controlled trial
Background Vitamin D may modify iron status through regulation of hepcidin and inflammatory pathways. This study aimed to investigate effects of maternal vitamin D supplementation on iron status in pregnancy and early infancy. Methods In a trial in Dhaka, Bangladesh, women (n=1300) were randomised to one of five vitamin D 3 regimens from 17 to 24 weeks’ gestation until 26 weeks postpartum (prenatal; postpartum doses): 0;0, 4200;0, 16 800;0, 28 000;0 or 28 000;28 000 IU/week. All participants received standard iron-folic acid supplementation. In this secondary analysis (n=998), we examined effects of prenatal;postpartum vitamin D on serum ferritin and other biomarkers of maternal iron status (transferrin saturation, total iron binding capacity, soluble transferrin receptor and hepcidin) at delivery, and infant ferritin and haemoglobin at 6 months of age. Using linear regression, we estimated per cent mean differences between each intervention group and placebo with 95% CIs, with and without adjustment for baseline ferritin or inflammatory biomarkers (C reactive protein and α-1-acid glycoprotein (AGP)). Results At delivery, ferritin concentrations were similar between each intervention group and placebo in unadjusted (n=998) and baseline ferritin-adjusted analyses (n=992; p>0.05). Compared with placebo, AGP was lower in each intervention group (per cent difference (95% CI) = −11% (−21 to –1.0), −14% (−23 to –3.5) and −11% (−19 to –2.0) in the 4200 IU/week, 16 800 IU/week and 28 000 IU/week groups, respectively; n=779). In the subgroup of women with baseline 25-hydroxyvitamin D < 30 nmol/L, ferritin was lower in each intervention group versus placebo (−23% (−37 to –5.0), −20% (−35 to –1.9) and −20% (−33 to –4.1) in the 4200 IU/week, 16 800 IU/week and 28 000 IU/week groups, respectively; n=645); effects were slightly attenuated after adjustment for inflammation (n=510). There were no effects of vitamin D on other iron biomarkers among women at delivery or infants aged 6 months. Conclusion These findings do not support improvement of iron status by vitamin D. The effect of prenatal vitamin D supplementation on ferritin may reflect an anti-inflammatory mechanism.