Effect of Calcium Supplementation on Blood Lead Levels in Pregnancy: A Randomized Control Trial Export

@article{citeulike:3183113, abstract = {Background: Prenatal lead exposure is associated with deficits in fetal growth and neurodevelopment. Calcium supplementation may attenuate fetal exposure by inhibiting mobilization of maternal bone lead and/or intestinal absorption of ingested lead. Objective: To evaluate the effect of 1,200 milligrams dietary calcium supplementation on maternal blood lead levels during pregnancy. Methods: In a double-blind, randomized control trial conducted from 2001-2003 in Mexico City, we randomly assigned 670 women in their first trimester of pregnancy to ingest calcium (N=334) or placebo (N=336). Subjects were followed through pregnancy and the supplement effect on maternal blood lead evaluated using an ” intent-to treat” analysis by a mixed effects regression model with random-intercept in 557 participants (83\%) who completed follow-up. We then conducted ” as treated” analyses using similar models stratified by treatment compliance. Results: Adjusting for baseline lead, age, trimester of pregnancy, and dietary energy and calcium intake, calcium was associated with an average 11\% reduction (0.4 μg/dL) in blood lead relative to placebo (p=0.004). This reduction was more evident in the 2nd trimester (-14\%, p<0.001) than in the 3rd (-8\%, p=0.107) and was strongest in the most compliant women, including those who: consumed >75\% pills (-24\%, p<0.001); or had baseline blood lead greater 5 than 5 μg/dL (-17\%, p<0.01); or reported use of lead-glazed ceramics and high bone lead (-31\%, p<0.01). Conclusion: Calcium supplementation was associated with modest reductions in blood lead when administered during pregnancy and may constitute an important secondary prevention effort to reduce circulating maternal lead and, consequently, fetal exposure}, author = {Ettinger, Adrienne S. and Lamadrid-Figueroa, H\'{e}ctor and T\'{e}llez-Rojo, Martha M. and Mercado-Garc\'{\i}a, Adriana and Peterson, Karen E. and Schwartz, Joel and Hu, Howard and Hern\'{a}ndez-Avila, Mauricio}, citeulike-article-id = {3183113}, day = {2}, journal = {Environmental Health Perspectives}, keywords = {ca, calcium, heavy\_metals, lead, pregnancy}, month = {September}, posted-at = {2008-09-03 00:41:01}, priority = {3}, title = {Effect of Calcium Supplementation on Blood Lead Levels in Pregnancy: A Randomized Control Trial}, year = {2008} }

TY - JOUR ID - citeulike:3183113 L3 - citeulike-article-id:3183113 N2 - Background: Prenatal lead exposure is associated with deficits in fetal growth and neurodevelopment. Calcium supplementation may attenuate fetal exposure by inhibiting mobilization of maternal bone lead and/or intestinal absorption of ingested lead. Objective: To evaluate the effect of 1,200 milligrams dietary calcium supplementation on maternal blood lead levels during pregnancy. Methods: In a double-blind, randomized control trial conducted from 2001-2003 in Mexico City, we randomly assigned 670 women in their first trimester of pregnancy to ingest calcium (N=334) or placebo (N=336). Subjects were followed through pregnancy and the supplement effect on maternal blood lead evaluated using an “intent-to treat” analysis by a mixed effects regression model with random-intercept in 557 participants (83%) who completed follow-up. We then conducted “as treated” analyses using similar models stratified by treatment compliance. Results: Adjusting for baseline lead, age, trimester of pregnancy, and dietary energy and calcium intake, calcium was associated with an average 11% reduction (0.4 μg/dL) in blood lead relative to placebo (p=0.004). This reduction was more evident in the 2nd trimester (-14%, p<0.001) than in the 3rd (-8%, p=0.107) and was strongest in the most compliant women, including those who: consumed >75% pills (-24%, p<0.001); or had baseline blood lead greater 5 than 5 μg/dL (-17%, p<0.01); or reported use of lead-glazed ceramics and high bone lead (-31%, p<0.01). Conclusion: Calcium supplementation was associated with modest reductions in blood lead when administered during pregnancy and may constitute an important secondary prevention effort to reduce circulating maternal lead and, consequently, fetal exposure JF - Environmental Health Perspectives TI - Effect of Calcium Supplementation on Blood Lead Levels in Pregnancy: A Randomized Control Trial KW - ca KW - calcium KW - heavy_metals KW - lead KW - pregnancy AU - Ettinger, Adrienne AU - Lamadrid-Figueroa, Héctor AU - Téllez-Rojo, Martha AU - Mercado-García, Adriana AU - Peterson, Karen AU - Schwartz, Joel AU - Hu, Howard AU - Hernández-Avila, Mauricio PY - 2008/09/02/ ER -