Serum cotinine and whole blood folate concentrations in pregnancy.
OBJECTIVE
Prenatal tobacco smoke exposure may be associated with low maternal folate levels that increase the risk of adverse infant and child health outcomes by reducing folate availability during fetal development.


METHODS
Using data from the Health Outcomes and Measures of the Environment Study, we examined the relationship between secondhand or active tobacco smoke exposure and whole blood folate concentrations in pregnant women from Cincinnati, Ohio (n = 362) at approximately 16-week gestation. We used multivariable linear regression to examine the association between continuous or categorical serum cotinine levels and whole blood folate levels, adjusting for sociodemographic, dietary, and perinatal variables.


RESULTS
After adjustment for potential confounders, an interquartile range increases in serum cotinine concentration (0.012-0.224 ng/mL) was suggestively associated with decreased whole blood folate levels (β, -23 nmol/L; 95% confidence interval (CI), -49, 3; P value = .08). Compared with unexposed women, reductions in mean whole blood folate were observed among active smokers (β, -94, 95% CI, 195, 6 nmol/L; P value = .40); smaller reductions were observed among women with secondhand exposure (β, 26; CI, 84, 32 nmol/L; P value = .07).


CONCLUSIONS
Consistent with prior studies, active smoking was associated with reduced whole blood folate levels among these pregnant women. Secondhand tobacco smoke exposures were associated with small and imprecise reductions in whole blood folate levels.
Department of Epidemiology, Brown University School of Public Health, Providence, RI.
Adila
A
Prasodjo
Division of Laboratory Sciences, National Center for Environmental Health, Nutritional Biomarkers Branch, Centers for Disease Control and Prevention, Atlanta, GA.
Christine M
CM
Pfeiffer
Division of Laboratory Sciences, National Center for Environmental Health, Nutritional Biomarkers Branch, Centers for Disease Control and Prevention, Atlanta, GA.
Zia
Z
Fazili
Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH.
Yingying
Y
Xu
Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH.
Stacey
S
Liddy
Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH.
Kimberly
K
Yolton
Department of Epidemiology, Brown University School of Public Health, Providence, RI.
David A
DA
Savitz
Faculty of Health and Sciences, Simon Fraser University, Burnaby, Canada; Child and Family Research Institute, BC Children's and Women's Hospital, Vancouver, Canada.
Bruce P
BP
Lanphear
Department of Epidemiology, Brown University School of Public Health, Providence, RI. Electronic address: joseph_braun_1@brown.edu.
Joseph M
JM
Braun
D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000097:blood; D003367:Cotinine / Q000097:blood*; D003430:Cross-Sectional Studies; D004032:Diet; D005260:Female; D005492:Folic Acid / Q000097:blood*; D006801:Humans; D007629:Kentucky; D008019:Life Style; D009820:Ohio; D011247:Pregnancy / Q000097:blood*; D011295:Prenatal Care; D012907:Smoking / Q000009:adverse effects*; D012959:Socioeconomic Factors; D053719:Tandem Mass Spectrometry; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*; D014803:Vitamin B Complex / Q000097:blood*
D015415:Biomarkers; D014028:Tobacco Smoke Pollution; D014803:Vitamin B Complex; D005492:Folic Acid; D003367:Cotinine
Epidemiology; Folic acid; Pregnancy; Smoking; Tobacco smoke pollution